diff --git a/PKG-INFO b/PKG-INFO
index 28016243..666beb73 100644
--- a/PKG-INFO
+++ b/PKG-INFO
@@ -1,202 +1,202 @@
 Metadata-Version: 2.1
 Name: swh.storage
-Version: 0.0.152
+Version: 0.0.153
 Summary: Software Heritage storage manager
 Home-page: https://forge.softwareheritage.org/diffusion/DSTO/
 Author: Software Heritage developers
 Author-email: swh-devel@inria.fr
 License: UNKNOWN
+Project-URL: Bug Reports, https://forge.softwareheritage.org/maniphest
 Project-URL: Funding, https://www.softwareheritage.org/donate
 Project-URL: Source, https://forge.softwareheritage.org/source/swh-storage
-Project-URL: Bug Reports, https://forge.softwareheritage.org/maniphest
 Description: swh-storage
         ===========
         
         Abstraction layer over the archive, allowing to access all stored source code
         artifacts as well as their metadata.
         
         See the
         [documentation](https://docs.softwareheritage.org/devel/swh-storage/index.html)
         for more details.
         
         ## Quick start
         
         ### Dependencies
         
         Python tests for this module include tests that cannot be run without
         a local Postgresql database, so you need the Postgresql server executable on
         your machine (no need to have a running Postgresql server). On a Debian-like
         host:
         
         ```
         $ sudo apt install libpq-dev postgresql
         ```
         
         ### Installation
         
         It is strongly recommended to use a virtualenv. In the following, we
         consider you work in a virtualenv named `swh`. See the
         [developer setup guide](https://docs.softwareheritage.org/devel/developer-setup.html#developer-setup)
         for a more details on how to setup a working environment.
         
         
         You can install the package directly from
         [pypi](https://pypi.org/p/swh.storage):
         
         ```
         (swh) :~$ pip install swh.storage
         [...]
         ```
         
         Or from sources:
         
         ```
         (swh) :~$ git clone https://forge.softwareheritage.org/source/swh-storage.git
         [...]
         (swh) :~$ cd swh-storage
         (swh) :~/swh-storage$ pip install .
         [...]
         ```
         
         Then you can check it's properly installed:
         ```
         (swh) :~$ swh storage --help
         Usage: swh storage [OPTIONS] COMMAND [ARGS]...
         
           Software Heritage Storage tools.
         
         Options:
           -h, --help  Show this message and exit.
         
         Commands:
           rpc-serve  Software Heritage Storage RPC server.
         ```
         
         
         ## Tests
         
         The best way of running Python tests for this module is to use
         [tox](https://tox.readthedocs.io/).
         
         ```
         (swh) :~$ pip install tox
         ```
         
         ### tox
         
         From the sources directory, simply use tox:
         
         ```
         (swh) :~/swh-storage$ tox
         [...]
         ========= 315 passed, 6 skipped, 15 warnings in 40.86 seconds ==========
         _______________________________ summary ________________________________
           flake8: commands succeeded
           py3: commands succeeded
           congratulations :)
         ```
         
         ## Development
         
         The storage server can be locally started. It requires a configuration file and
         a running Postgresql database.
         
         ### Sample configuration
         
         A typical configuration `storage.yml` file is:
         
         ```
         storage:
           cls: local
           args:
             db: "dbname=softwareheritage-dev user=<user> password=<pwd>"
             objstorage:
               cls: pathslicing
               args:
                 root: /tmp/swh-storage/
                 slicing: 0:2/2:4/4:6
         ```
         
         which means, this uses:
         
         - a local storage instance whose db connection is to
           `softwareheritage-dev` local instance,
         
         - the objstorage uses a local objstorage instance whose:
         
           - `root` path is /tmp/swh-storage,
         
           - slicing scheme is `0:2/2:4/4:6`. This means that the identifier of
             the content (sha1) which will be stored on disk at first level
             with the first 2 hex characters, the second level with the next 2
             hex characters and the third level with the next 2 hex
             characters. And finally the complete hash file holding the raw
             content. For example: 00062f8bd330715c4f819373653d97b3cd34394c
             will be stored at 00/06/2f/00062f8bd330715c4f819373653d97b3cd34394c
         
         Note that the `root` path should exist on disk before starting the server.
         
         
         ### Starting the storage server
         
         If the python package has been properly installed (e.g. in a virtual env), you
         should be able to use the command:
         
         ```
         (swh) :~/swh-storage$ swh storage rpc-serve storage.yml
         ```
         
         This runs a local swh-storage api at 5002 port.
         
         ```
         (swh) :~/swh-storage$ curl http://127.0.0.1:5002
         <html>
         <head><title>Software Heritage storage server</title></head>
         <body>
         <p>You have reached the
         <a href="https://www.softwareheritage.org/">Software Heritage</a>
         storage server.<br />
         See its
         <a href="https://docs.softwareheritage.org/devel/swh-storage/">documentation
         and API</a> for more information</p>
         ```
         
         ### And then what?
         
         In your upper layer
         ([loader-git](https://forge.softwareheritage.org/source/swh-loader-git/),
         [loader-svn](https://forge.softwareheritage.org/source/swh-loader-svn/),
         etc...), you can define a remote storage with this snippet of yaml
         configuration.
         
         ```
         storage:
           cls: remote
           args:
             url: http://localhost:5002/
         ```
         
         You could directly define a local storage with the following snippet:
         
         ```
         storage:
           cls: local
           args:
             db: service=swh-dev
             objstorage:
               cls: pathslicing
               args:
                 root: /home/storage/swh-storage/
                 slicing: 0:2/2:4/4:6
         ```
         
 Platform: UNKNOWN
 Classifier: Programming Language :: Python :: 3
 Classifier: Intended Audience :: Developers
 Classifier: License :: OSI Approved :: GNU General Public License v3 (GPLv3)
 Classifier: Operating System :: OS Independent
 Classifier: Development Status :: 5 - Production/Stable
 Description-Content-Type: text/markdown
-Provides-Extra: schemata
 Provides-Extra: testing
 Provides-Extra: journal
+Provides-Extra: schemata
diff --git a/swh.storage.egg-info/PKG-INFO b/swh.storage.egg-info/PKG-INFO
index 28016243..666beb73 100644
--- a/swh.storage.egg-info/PKG-INFO
+++ b/swh.storage.egg-info/PKG-INFO
@@ -1,202 +1,202 @@
 Metadata-Version: 2.1
 Name: swh.storage
-Version: 0.0.152
+Version: 0.0.153
 Summary: Software Heritage storage manager
 Home-page: https://forge.softwareheritage.org/diffusion/DSTO/
 Author: Software Heritage developers
 Author-email: swh-devel@inria.fr
 License: UNKNOWN
+Project-URL: Bug Reports, https://forge.softwareheritage.org/maniphest
 Project-URL: Funding, https://www.softwareheritage.org/donate
 Project-URL: Source, https://forge.softwareheritage.org/source/swh-storage
-Project-URL: Bug Reports, https://forge.softwareheritage.org/maniphest
 Description: swh-storage
         ===========
         
         Abstraction layer over the archive, allowing to access all stored source code
         artifacts as well as their metadata.
         
         See the
         [documentation](https://docs.softwareheritage.org/devel/swh-storage/index.html)
         for more details.
         
         ## Quick start
         
         ### Dependencies
         
         Python tests for this module include tests that cannot be run without
         a local Postgresql database, so you need the Postgresql server executable on
         your machine (no need to have a running Postgresql server). On a Debian-like
         host:
         
         ```
         $ sudo apt install libpq-dev postgresql
         ```
         
         ### Installation
         
         It is strongly recommended to use a virtualenv. In the following, we
         consider you work in a virtualenv named `swh`. See the
         [developer setup guide](https://docs.softwareheritage.org/devel/developer-setup.html#developer-setup)
         for a more details on how to setup a working environment.
         
         
         You can install the package directly from
         [pypi](https://pypi.org/p/swh.storage):
         
         ```
         (swh) :~$ pip install swh.storage
         [...]
         ```
         
         Or from sources:
         
         ```
         (swh) :~$ git clone https://forge.softwareheritage.org/source/swh-storage.git
         [...]
         (swh) :~$ cd swh-storage
         (swh) :~/swh-storage$ pip install .
         [...]
         ```
         
         Then you can check it's properly installed:
         ```
         (swh) :~$ swh storage --help
         Usage: swh storage [OPTIONS] COMMAND [ARGS]...
         
           Software Heritage Storage tools.
         
         Options:
           -h, --help  Show this message and exit.
         
         Commands:
           rpc-serve  Software Heritage Storage RPC server.
         ```
         
         
         ## Tests
         
         The best way of running Python tests for this module is to use
         [tox](https://tox.readthedocs.io/).
         
         ```
         (swh) :~$ pip install tox
         ```
         
         ### tox
         
         From the sources directory, simply use tox:
         
         ```
         (swh) :~/swh-storage$ tox
         [...]
         ========= 315 passed, 6 skipped, 15 warnings in 40.86 seconds ==========
         _______________________________ summary ________________________________
           flake8: commands succeeded
           py3: commands succeeded
           congratulations :)
         ```
         
         ## Development
         
         The storage server can be locally started. It requires a configuration file and
         a running Postgresql database.
         
         ### Sample configuration
         
         A typical configuration `storage.yml` file is:
         
         ```
         storage:
           cls: local
           args:
             db: "dbname=softwareheritage-dev user=<user> password=<pwd>"
             objstorage:
               cls: pathslicing
               args:
                 root: /tmp/swh-storage/
                 slicing: 0:2/2:4/4:6
         ```
         
         which means, this uses:
         
         - a local storage instance whose db connection is to
           `softwareheritage-dev` local instance,
         
         - the objstorage uses a local objstorage instance whose:
         
           - `root` path is /tmp/swh-storage,
         
           - slicing scheme is `0:2/2:4/4:6`. This means that the identifier of
             the content (sha1) which will be stored on disk at first level
             with the first 2 hex characters, the second level with the next 2
             hex characters and the third level with the next 2 hex
             characters. And finally the complete hash file holding the raw
             content. For example: 00062f8bd330715c4f819373653d97b3cd34394c
             will be stored at 00/06/2f/00062f8bd330715c4f819373653d97b3cd34394c
         
         Note that the `root` path should exist on disk before starting the server.
         
         
         ### Starting the storage server
         
         If the python package has been properly installed (e.g. in a virtual env), you
         should be able to use the command:
         
         ```
         (swh) :~/swh-storage$ swh storage rpc-serve storage.yml
         ```
         
         This runs a local swh-storage api at 5002 port.
         
         ```
         (swh) :~/swh-storage$ curl http://127.0.0.1:5002
         <html>
         <head><title>Software Heritage storage server</title></head>
         <body>
         <p>You have reached the
         <a href="https://www.softwareheritage.org/">Software Heritage</a>
         storage server.<br />
         See its
         <a href="https://docs.softwareheritage.org/devel/swh-storage/">documentation
         and API</a> for more information</p>
         ```
         
         ### And then what?
         
         In your upper layer
         ([loader-git](https://forge.softwareheritage.org/source/swh-loader-git/),
         [loader-svn](https://forge.softwareheritage.org/source/swh-loader-svn/),
         etc...), you can define a remote storage with this snippet of yaml
         configuration.
         
         ```
         storage:
           cls: remote
           args:
             url: http://localhost:5002/
         ```
         
         You could directly define a local storage with the following snippet:
         
         ```
         storage:
           cls: local
           args:
             db: service=swh-dev
             objstorage:
               cls: pathslicing
               args:
                 root: /home/storage/swh-storage/
                 slicing: 0:2/2:4/4:6
         ```
         
 Platform: UNKNOWN
 Classifier: Programming Language :: Python :: 3
 Classifier: Intended Audience :: Developers
 Classifier: License :: OSI Approved :: GNU General Public License v3 (GPLv3)
 Classifier: Operating System :: OS Independent
 Classifier: Development Status :: 5 - Production/Stable
 Description-Content-Type: text/markdown
-Provides-Extra: schemata
 Provides-Extra: testing
 Provides-Extra: journal
+Provides-Extra: schemata
diff --git a/swh.storage.egg-info/SOURCES.txt b/swh.storage.egg-info/SOURCES.txt
index 8283e885..b52bc5ad 100644
--- a/swh.storage.egg-info/SOURCES.txt
+++ b/swh.storage.egg-info/SOURCES.txt
@@ -1,216 +1,217 @@
 MANIFEST.in
 Makefile
 Makefile.local
 README.md
 requirements-swh.txt
 requirements.txt
 setup.py
 version.txt
 bin/swh-storage-add-dir
 sql/.gitignore
 sql/Makefile
 sql/TODO
 sql/clusters.dot
 sql/bin/db-upgrade
 sql/bin/dot_add_content
 sql/doc/json/.gitignore
 sql/doc/json/Makefile
 sql/doc/json/entity.lister_metadata.schema.json
 sql/doc/json/entity.metadata.schema.json
 sql/doc/json/entity_history.lister_metadata.schema.json
 sql/doc/json/entity_history.metadata.schema.json
 sql/doc/json/fetch_history.result.schema.json
 sql/doc/json/list_history.result.schema.json
 sql/doc/json/listable_entity.list_params.schema.json
 sql/doc/json/origin_visit.metadata.json
 sql/doc/json/tool.tool_configuration.schema.json
 sql/json/.gitignore
 sql/json/Makefile
 sql/json/entity.lister_metadata.schema.json
 sql/json/entity.metadata.schema.json
 sql/json/entity_history.lister_metadata.schema.json
 sql/json/entity_history.metadata.schema.json
 sql/json/fetch_history.result.schema.json
 sql/json/list_history.result.schema.json
 sql/json/listable_entity.list_params.schema.json
 sql/json/origin_visit.metadata.json
 sql/json/tool.tool_configuration.schema.json
 sql/upgrades/015.sql
 sql/upgrades/016.sql
 sql/upgrades/017.sql
 sql/upgrades/018.sql
 sql/upgrades/019.sql
 sql/upgrades/020.sql
 sql/upgrades/021.sql
 sql/upgrades/022.sql
 sql/upgrades/023.sql
 sql/upgrades/024.sql
 sql/upgrades/025.sql
 sql/upgrades/026.sql
 sql/upgrades/027.sql
 sql/upgrades/028.sql
 sql/upgrades/029.sql
 sql/upgrades/030.sql
 sql/upgrades/032.sql
 sql/upgrades/033.sql
 sql/upgrades/034.sql
 sql/upgrades/035.sql
 sql/upgrades/036.sql
 sql/upgrades/037.sql
 sql/upgrades/038.sql
 sql/upgrades/039.sql
 sql/upgrades/040.sql
 sql/upgrades/041.sql
 sql/upgrades/042.sql
 sql/upgrades/043.sql
 sql/upgrades/044.sql
 sql/upgrades/045.sql
 sql/upgrades/046.sql
 sql/upgrades/047.sql
 sql/upgrades/048.sql
 sql/upgrades/049.sql
 sql/upgrades/050.sql
 sql/upgrades/051.sql
 sql/upgrades/052.sql
 sql/upgrades/053.sql
 sql/upgrades/054.sql
 sql/upgrades/055.sql
 sql/upgrades/056.sql
 sql/upgrades/057.sql
 sql/upgrades/058.sql
 sql/upgrades/059.sql
 sql/upgrades/060.sql
 sql/upgrades/061.sql
 sql/upgrades/062.sql
 sql/upgrades/063.sql
 sql/upgrades/064.sql
 sql/upgrades/065.sql
 sql/upgrades/066.sql
 sql/upgrades/067.sql
 sql/upgrades/068.sql
 sql/upgrades/069.sql
 sql/upgrades/070.sql
 sql/upgrades/071.sql
 sql/upgrades/072.sql
 sql/upgrades/073.sql
 sql/upgrades/074.sql
 sql/upgrades/075.sql
 sql/upgrades/076.sql
 sql/upgrades/077.sql
 sql/upgrades/078.sql
 sql/upgrades/079.sql
 sql/upgrades/080.sql
 sql/upgrades/081.sql
 sql/upgrades/082.sql
 sql/upgrades/083.sql
 sql/upgrades/084.sql
 sql/upgrades/085.sql
 sql/upgrades/086.sql
 sql/upgrades/087.sql
 sql/upgrades/088.sql
 sql/upgrades/089.sql
 sql/upgrades/090.sql
 sql/upgrades/091.sql
 sql/upgrades/092.sql
 sql/upgrades/093.sql
 sql/upgrades/094.sql
 sql/upgrades/095.sql
 sql/upgrades/096.sql
 sql/upgrades/097.sql
 sql/upgrades/098.sql
 sql/upgrades/099.sql
 sql/upgrades/100.sql
 sql/upgrades/101.sql
 sql/upgrades/102.sql
 sql/upgrades/103.sql
 sql/upgrades/104.sql
 sql/upgrades/105.sql
 sql/upgrades/106.sql
 sql/upgrades/107.sql
 sql/upgrades/108.sql
 sql/upgrades/109.sql
 sql/upgrades/110.sql
 sql/upgrades/111.sql
 sql/upgrades/112.sql
 sql/upgrades/113.sql
 sql/upgrades/114.sql
 sql/upgrades/115.sql
 sql/upgrades/116.sql
 sql/upgrades/117.sql
 sql/upgrades/118.sql
 sql/upgrades/119.sql
 sql/upgrades/120.sql
 sql/upgrades/121.sql
 sql/upgrades/122.sql
 sql/upgrades/123.sql
 sql/upgrades/124.sql
 sql/upgrades/125.sql
 sql/upgrades/126.sql
 sql/upgrades/127.sql
 sql/upgrades/128.sql
 sql/upgrades/129.sql
 sql/upgrades/130.sql
 sql/upgrades/131.sql
 sql/upgrades/132.sql
 sql/upgrades/133.sql
 sql/upgrades/134.sql
 sql/upgrades/135.sql
 sql/upgrades/136.sql
 sql/upgrades/137.sql
 sql/upgrades/138.sql
 sql/upgrades/139.sql
 sql/upgrades/140.sql
 swh/__init__.py
 swh.storage.egg-info/PKG-INFO
 swh.storage.egg-info/SOURCES.txt
 swh.storage.egg-info/dependency_links.txt
 swh.storage.egg-info/entry_points.txt
 swh.storage.egg-info/requires.txt
 swh.storage.egg-info/top_level.txt
 swh/storage/__init__.py
 swh/storage/buffer.py
 swh/storage/cli.py
 swh/storage/common.py
 swh/storage/converters.py
 swh/storage/db.py
 swh/storage/exc.py
 swh/storage/filter.py
 swh/storage/in_memory.py
 swh/storage/py.typed
 swh/storage/storage.py
 swh/storage/algos/__init__.py
 swh/storage/algos/diff.py
 swh/storage/algos/dir_iterators.py
 swh/storage/algos/origin.py
 swh/storage/algos/revisions_walker.py
 swh/storage/algos/snapshot.py
 swh/storage/api/__init__.py
 swh/storage/api/client.py
 swh/storage/api/server.py
-swh/storage/api/wsgi.py
 swh/storage/schemata/__init__.py
 swh/storage/schemata/distribution.py
 swh/storage/sql/10-swh-init.sql
 swh/storage/sql/20-swh-enums.sql
 swh/storage/sql/30-swh-schema.sql
 swh/storage/sql/40-swh-func.sql
 swh/storage/sql/60-swh-indexes.sql
 swh/storage/sql/70-swh-triggers.sql
 swh/storage/tests/__init__.py
+swh/storage/tests/conftest.py
 swh/storage/tests/generate_data_test.py
+swh/storage/tests/storage_data.py
 swh/storage/tests/storage_testing.py
 swh/storage/tests/test_api_client.py
 swh/storage/tests/test_buffer.py
 swh/storage/tests/test_converters.py
 swh/storage/tests/test_db.py
 swh/storage/tests/test_filter.py
 swh/storage/tests/test_in_memory.py
 swh/storage/tests/test_init.py
 swh/storage/tests/test_server.py
 swh/storage/tests/test_storage.py
 swh/storage/tests/algos/__init__.py
 swh/storage/tests/algos/test_diff.py
 swh/storage/tests/algos/test_dir_iterator.py
 swh/storage/tests/algos/test_origin.py
 swh/storage/tests/algos/test_revisions_walker.py
 swh/storage/tests/algos/test_snapshot.py
\ No newline at end of file
diff --git a/swh.storage.egg-info/requires.txt b/swh.storage.egg-info/requires.txt
index 3710f7f6..3648644d 100644
--- a/swh.storage.egg-info/requires.txt
+++ b/swh.storage.egg-info/requires.txt
@@ -1,21 +1,22 @@
 click
 flask
 psycopg2
 python-dateutil
 vcversioner
 aiohttp
 swh.core[db,http]>=0.0.65
 swh.model>=0.0.41
 swh.objstorage>=0.0.17
 
 [journal]
 swh.journal>=0.0.17
 
 [schemata]
 SQLAlchemy
 
 [testing]
 hypothesis>=3.11.0
 pytest
+pytest-postgresql
 sqlalchemy-stubs
 swh.journal>=0.0.17
diff --git a/swh/storage/api/client.py b/swh/storage/api/client.py
index be389a57..865b3663 100644
--- a/swh/storage/api/client.py
+++ b/swh/storage/api/client.py
@@ -1,265 +1,268 @@
 # Copyright (C) 2015-2017  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import warnings
 
 from swh.core.api import RPCClient
 
 from ..exc import StorageAPIError
 
 
 class RemoteStorage(RPCClient):
     """Proxy to a remote storage API"""
     api_exception = StorageAPIError
 
     def check_config(self, *, check_write):
         return self.post('check_config', {'check_write': check_write})
 
     def reset(self):
         return self.post('reset', {})
 
     def content_add(self, content):
         return self.post('content/add', {'content': content})
 
     def content_add_metadata(self, content):
         return self.post('content/add_metadata', {'content': content})
 
     def content_update(self, content, keys=[]):
         return self.post('content/update', {'content': content,
                                             'keys': keys})
 
     def content_missing(self, content, key_hash='sha1'):
         return self.post('content/missing', {'content': content,
                                              'key_hash': key_hash})
 
     def content_missing_per_sha1(self, contents):
         return self.post('content/missing/sha1', {'contents': contents})
 
     def skipped_content_missing(self, contents):
         return self.post('content/skipped/missing', {'contents': contents})
 
     def content_get(self, content):
         return self.post('content/data', {'content': content})
 
     def content_get_metadata(self, content):
         return self.post('content/metadata', {'content': content})
 
     def content_get_range(self, start, end, limit=1000):
         return self.post('content/range', {'start': start,
                                            'end': end,
                                            'limit': limit})
 
     def content_find(self, content):
         return self.post('content/present', {'content': content})
 
     def directory_add(self, directories):
         return self.post('directory/add', {'directories': directories})
 
     def directory_missing(self, directories):
         return self.post('directory/missing', {'directories': directories})
 
     def directory_ls(self, directory, recursive=False):
         return self.post('directory/ls', {'directory': directory,
                                           'recursive': recursive})
 
     def revision_get(self, revisions):
         return self.post('revision', {'revisions': revisions})
 
     def revision_log(self, revisions, limit=None):
         return self.post('revision/log', {'revisions': revisions,
                                           'limit': limit})
 
     def revision_shortlog(self, revisions, limit=None):
         return self.post('revision/shortlog', {'revisions': revisions,
                                                'limit': limit})
 
     def revision_add(self, revisions):
         return self.post('revision/add', {'revisions': revisions})
 
     def revision_missing(self, revisions):
         return self.post('revision/missing', {'revisions': revisions})
 
     def release_add(self, releases):
         return self.post('release/add', {'releases': releases})
 
     def release_get(self, releases):
         return self.post('release', {'releases': releases})
 
     def release_missing(self, releases):
         return self.post('release/missing', {'releases': releases})
 
     def object_find_by_sha1_git(self, ids):
         return self.post('object/find_by_sha1_git', {'ids': ids})
 
     def snapshot_add(self, snapshots):
         return self.post('snapshot/add', {'snapshots': snapshots})
 
     def snapshot_get(self, snapshot_id):
         return self.post('snapshot', {
             'snapshot_id': snapshot_id
         })
 
     def snapshot_get_by_origin_visit(self, origin, visit):
         return self.post('snapshot/by_origin_visit', {
             'origin': origin,
             'visit': visit
         })
 
     def snapshot_get_latest(self, origin, allowed_statuses=None):
         return self.post('snapshot/latest', {
             'origin': origin,
             'allowed_statuses': allowed_statuses
         })
 
     def snapshot_count_branches(self, snapshot_id):
         return self.post('snapshot/count_branches', {
             'snapshot_id': snapshot_id
         })
 
     def snapshot_get_branches(self, snapshot_id, branches_from=b'',
                               branches_count=1000, target_types=None):
         return self.post('snapshot/get_branches', {
             'snapshot_id': snapshot_id,
             'branches_from': branches_from,
             'branches_count': branches_count,
             'target_types': target_types
         })
 
     def origin_get(self, origins=None, *, origin=None):
         if origin is None:
             if origins is None:
                 raise TypeError('origin_get expected 1 argument')
         else:
             assert origins is None
             origins = origin
             warnings.warn("argument 'origin' of origin_get was renamed "
                           "to 'origins' in v0.0.123.",
                           DeprecationWarning)
         return self.post('origin/get', {'origins': origins})
 
     def origin_search(self, url_pattern, offset=0, limit=50, regexp=False,
                       with_visit=False):
         return self.post('origin/search', {'url_pattern': url_pattern,
                                            'offset': offset,
                                            'limit': limit,
                                            'regexp': regexp,
                                            'with_visit': with_visit})
 
     def origin_count(self, url_pattern, regexp=False, with_visit=False):
         return self.post('origin/count', {'url_pattern': url_pattern,
                                           'regexp': regexp,
                                           'with_visit': with_visit})
 
     def origin_get_range(self, origin_from=1, origin_count=100):
         return self.post('origin/get_range', {'origin_from': origin_from,
                                               'origin_count': origin_count})
 
     def origin_add(self, origins):
         return self.post('origin/add_multi', {'origins': origins})
 
     def origin_add_one(self, origin):
         return self.post('origin/add', {'origin': origin})
 
     def origin_visit_add(self, origin, date, type=None):
         return self.post(
             'origin/visit/add',
             {'origin': origin, 'date': date, 'type': type})
 
     def origin_visit_update(self, origin, visit_id, status=None,
                             metadata=None, snapshot=None):
         return self.post('origin/visit/update', {'origin': origin,
                                                  'visit_id': visit_id,
                                                  'status': status,
                                                  'metadata': metadata,
                                                  'snapshot': snapshot})
 
     def origin_visit_upsert(self, visits):
         return self.post('origin/visit/upsert', {'visits': visits})
 
     def origin_visit_get(self, origin, last_visit=None, limit=None):
         return self.post('origin/visit/get', {
             'origin': origin, 'last_visit': last_visit, 'limit': limit})
 
     def origin_visit_find_by_date(self, origin, visit_date, limit=None):
         return self.post('origin/visit/find_by_date', {
             'origin': origin, 'visit_date': visit_date})
 
     def origin_visit_get_by(self, origin, visit):
         return self.post('origin/visit/getby', {'origin': origin,
                                                 'visit': visit})
 
     def origin_visit_get_latest(self, origin, allowed_statuses=None,
                                 require_snapshot=False):
         return self.post(
             'origin/visit/get_latest',
             {'origin': origin, 'allowed_statuses': allowed_statuses,
              'require_snapshot': require_snapshot})
 
     def fetch_history_start(self, origin_id):
         return self.post('fetch_history/start', {'origin_id': origin_id})
 
     def fetch_history_end(self, fetch_history_id, data):
         return self.post('fetch_history/end',
                          {'fetch_history_id': fetch_history_id,
                           'data': data})
 
     def fetch_history_get(self, fetch_history_id):
         return self.get('fetch_history', {'id': fetch_history_id})
 
     def stat_counters(self):
         return self.get('stat/counters')
 
+    def refresh_stat_counters(self):
+        return self.get('stat/refresh')
+
     def directory_entry_get_by_path(self, directory, paths):
         return self.post('directory/path', dict(directory=directory,
                                                 paths=paths))
 
     def tool_add(self, tools):
         return self.post('tool/add', {'tools': tools})
 
     def tool_get(self, tool):
         return self.post('tool/data', {'tool': tool})
 
     def origin_metadata_add(self, origin_id, ts, provider, tool, metadata):
         return self.post('origin/metadata/add', {'origin_id': origin_id,
                                                  'ts': ts,
                                                  'provider': provider,
                                                  'tool': tool,
                                                  'metadata': metadata})
 
     def origin_metadata_get_by(self, origin_id, provider_type=None):
         return self.post('origin/metadata/get', {
             'origin_id': origin_id,
             'provider_type': provider_type
         })
 
     def metadata_provider_add(self, provider_name, provider_type, provider_url,
                               metadata):
         return self.post('provider/add', {'provider_name': provider_name,
                                           'provider_type': provider_type,
                                           'provider_url': provider_url,
                                           'metadata': metadata})
 
     def metadata_provider_get(self, provider_id):
         return self.post('provider/get', {'provider_id': provider_id})
 
     def metadata_provider_get_by(self, provider):
         return self.post('provider/getby', {'provider': provider})
 
     def diff_directories(self, from_dir, to_dir, track_renaming=False):
         return self.post('algos/diff_directories',
                          {'from_dir': from_dir,
                           'to_dir': to_dir,
                           'track_renaming': track_renaming})
 
     def diff_revisions(self, from_rev, to_rev, track_renaming=False):
         return self.post('algos/diff_revisions',
                          {'from_rev': from_rev,
                           'to_rev': to_rev,
                           'track_renaming': track_renaming})
 
     def diff_revision(self, revision, track_renaming=False):
         return self.post('algos/diff_revision',
                          {'revision': revision,
                           'track_renaming': track_renaming})
diff --git a/swh/storage/api/server.py b/swh/storage/api/server.py
index 9c52c4bb..797c5452 100644
--- a/swh/storage/api/server.py
+++ b/swh/storage/api/server.py
@@ -1,613 +1,619 @@
 # Copyright (C) 2015-2019  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import os
 import logging
 
 from flask import request
 from functools import wraps
 
 from swh.core import config
 from swh.storage import get_storage as get_swhstorage
 from swh.core.api import (RPCServerApp, decode_request,
                           error_handler,
                           encode_data_server as encode_data)
 from swh.core.statsd import statsd
 
 
 app = RPCServerApp(__name__)
 storage = None
 
 
 OPERATIONS_METRIC = 'swh_storage_operations_total'
 OPERATIONS_UNIT_METRIC = "swh_storage_operations_{unit}_total"
 DURATION_METRIC = "swh_storage_request_duration_seconds"
 
 
 def timed(f):
     """Time that function!
 
     """
     @wraps(f)
     def d(*a, **kw):
         with statsd.timed(DURATION_METRIC, tags={'endpoint': f.__name__}):
             return f(*a, **kw)
 
     return d
 
 
 def encode(f):
     @wraps(f)
     def d(*a, **kw):
         r = f(*a, **kw)
         return encode_data(r)
 
     return d
 
 
 def send_metric(metric, count, method_name):
     """Send statsd metric with count for method `method_name`
 
     If count is 0, the metric is discarded.  If the metric is not
     parseable, the metric is discarded with a log message.
 
     Args:
         metric (str): Metric's name (e.g content:add, content:add:bytes)
         count (int): Associated value for the metric
         method_name (str): Method's name
 
     Returns:
         Bool to explicit if metric has been set or not
     """
     if count == 0:
         return False
 
     metric_type = metric.split(':')
     _length = len(metric_type)
     if _length == 2:
         object_type, operation = metric_type
         metric_name = OPERATIONS_METRIC
     elif _length == 3:
         object_type, operation, unit = metric_type
         metric_name = OPERATIONS_UNIT_METRIC.format(unit=unit)
     else:
         logging.warning('Skipping unknown metric {%s: %s}' % (
             metric, count))
         return False
 
     statsd.increment(
         metric_name, count, tags={
             'endpoint': method_name,
             'object_type': object_type,
             'operation': operation,
         })
     return True
 
 
 def process_metrics(f):
     """Increment object counters for the decorated function.
 
     """
     @wraps(f)
     def d(*a, **kw):
         r = f(*a, **kw)
         for metric, count in r.items():
             send_metric(metric=metric, count=count, method_name=f.__name__)
 
         return r
 
     return d
 
 
 @app.errorhandler(Exception)
 def my_error_handler(exception):
     return error_handler(exception, encode_data)
 
 
 def get_storage():
     global storage
     if not storage:
         storage = get_swhstorage(**app.config['storage'])
 
     return storage
 
 
 @app.route('/')
 @timed
 def index():
     return '''<html>
 <head><title>Software Heritage storage server</title></head>
 <body>
 <p>You have reached the
 <a href="https://www.softwareheritage.org/">Software Heritage</a>
 storage server.<br />
 See its
 <a href="https://docs.softwareheritage.org/devel/swh-storage/">documentation
 and API</a> for more information</p>
 </body>
 </html>'''
 
 
 @app.route('/check_config', methods=['POST'])
 @timed
 def check_config():
     return encode_data(get_storage().check_config(**decode_request(request)))
 
 
 @app.route('/reset', methods=['POST'])
 @timed
 def reset():
     return encode_data(get_storage().reset(**decode_request(request)))
 
 
 @app.route('/content/missing', methods=['POST'])
 @timed
 def content_missing():
     return encode_data(get_storage().content_missing(
         **decode_request(request)))
 
 
 @app.route('/content/missing/sha1', methods=['POST'])
 @timed
 def content_missing_per_sha1():
     return encode_data(get_storage().content_missing_per_sha1(
         **decode_request(request)))
 
 
 @app.route('/content/skipped/missing', methods=['POST'])
 @timed
 def skipped_content_missing():
     return encode_data(get_storage().skipped_content_missing(
         **decode_request(request)))
 
 
 @app.route('/content/present', methods=['POST'])
 @timed
 def content_find():
     return encode_data(get_storage().content_find(**decode_request(request)))
 
 
 @app.route('/content/add', methods=['POST'])
 @timed
 @encode
 @process_metrics
 def content_add():
     return get_storage().content_add(**decode_request(request))
 
 
 @app.route('/content/add_metadata', methods=['POST'])
 @timed
 @encode
 @process_metrics
 def content_add_metadata():
     return get_storage().content_add_metadata(**decode_request(request))
 
 
 @app.route('/content/update', methods=['POST'])
 @timed
 def content_update():
     return encode_data(get_storage().content_update(**decode_request(request)))
 
 
 @app.route('/content/data', methods=['POST'])
 @timed
 def content_get():
     return encode_data(get_storage().content_get(**decode_request(request)))
 
 
 @app.route('/content/metadata', methods=['POST'])
 @timed
 def content_get_metadata():
     return encode_data(get_storage().content_get_metadata(
         **decode_request(request)))
 
 
 @app.route('/content/range', methods=['POST'])
 @timed
 def content_get_range():
     return encode_data(get_storage().content_get_range(
         **decode_request(request)))
 
 
 @app.route('/directory/missing', methods=['POST'])
 @timed
 def directory_missing():
     return encode_data(get_storage().directory_missing(
         **decode_request(request)))
 
 
 @app.route('/directory/add', methods=['POST'])
 @timed
 @encode
 @process_metrics
 def directory_add():
     return get_storage().directory_add(**decode_request(request))
 
 
 @app.route('/directory/path', methods=['POST'])
 @timed
 def directory_entry_get_by_path():
     return encode_data(get_storage().directory_entry_get_by_path(
         **decode_request(request)))
 
 
 @app.route('/directory/ls', methods=['POST'])
 @timed
 def directory_ls():
     return encode_data(get_storage().directory_ls(
         **decode_request(request)))
 
 
 @app.route('/revision/add', methods=['POST'])
 @timed
 @encode
 @process_metrics
 def revision_add():
     return get_storage().revision_add(**decode_request(request))
 
 
 @app.route('/revision', methods=['POST'])
 @timed
 def revision_get():
     return encode_data(get_storage().revision_get(**decode_request(request)))
 
 
 @app.route('/revision/log', methods=['POST'])
 @timed
 def revision_log():
     return encode_data(get_storage().revision_log(**decode_request(request)))
 
 
 @app.route('/revision/shortlog', methods=['POST'])
 @timed
 def revision_shortlog():
     return encode_data(get_storage().revision_shortlog(
         **decode_request(request)))
 
 
 @app.route('/revision/missing', methods=['POST'])
 @timed
 def revision_missing():
     return encode_data(get_storage().revision_missing(
         **decode_request(request)))
 
 
 @app.route('/release/add', methods=['POST'])
 @timed
 @encode
 @process_metrics
 def release_add():
     return get_storage().release_add(**decode_request(request))
 
 
 @app.route('/release', methods=['POST'])
 @timed
 def release_get():
     return encode_data(get_storage().release_get(**decode_request(request)))
 
 
 @app.route('/release/missing', methods=['POST'])
 @timed
 def release_missing():
     return encode_data(get_storage().release_missing(
         **decode_request(request)))
 
 
 @app.route('/object/find_by_sha1_git', methods=['POST'])
 @timed
 def object_find_by_sha1_git():
     return encode_data(get_storage().object_find_by_sha1_git(
         **decode_request(request)))
 
 
 @app.route('/snapshot/add', methods=['POST'])
 @timed
 @encode
 @process_metrics
 def snapshot_add():
     req_data = decode_request(request)
     return get_storage().snapshot_add(**req_data)
 
 
 @app.route('/snapshot', methods=['POST'])
 @timed
 def snapshot_get():
     return encode_data(get_storage().snapshot_get(**decode_request(request)))
 
 
 @app.route('/snapshot/by_origin_visit', methods=['POST'])
 @timed
 def snapshot_get_by_origin_visit():
     return encode_data(get_storage().snapshot_get_by_origin_visit(
         **decode_request(request)))
 
 
 @app.route('/snapshot/latest', methods=['POST'])
 @timed
 def snapshot_get_latest():
     return encode_data(get_storage().snapshot_get_latest(
         **decode_request(request)))
 
 
 @app.route('/snapshot/count_branches', methods=['POST'])
 @timed
 def snapshot_count_branches():
     return encode_data(get_storage().snapshot_count_branches(
         **decode_request(request)))
 
 
 @app.route('/snapshot/get_branches', methods=['POST'])
 @timed
 def snapshot_get_branches():
     return encode_data(get_storage().snapshot_get_branches(
         **decode_request(request)))
 
 
 @app.route('/origin/get', methods=['POST'])
 @timed
 def origin_get():
     return encode_data(get_storage().origin_get(**decode_request(request)))
 
 
 @app.route('/origin/get_range', methods=['POST'])
 @timed
 def origin_get_range():
     return encode_data(get_storage().origin_get_range(
         **decode_request(request)))
 
 
 @app.route('/origin/search', methods=['POST'])
 @timed
 def origin_search():
     return encode_data(get_storage().origin_search(**decode_request(request)))
 
 
 @app.route('/origin/count', methods=['POST'])
 @timed
 def origin_count():
     return encode_data(get_storage().origin_count(**decode_request(request)))
 
 
 @app.route('/origin/add_multi', methods=['POST'])
 @timed
 @encode
 def origin_add():
     origins = get_storage().origin_add(**decode_request(request))
     send_metric('origin:add', count=len(origins), method_name='origin_add')
     return origins
 
 
 @app.route('/origin/add', methods=['POST'])
 @timed
 @encode
 def origin_add_one():
     origin = get_storage().origin_add_one(**decode_request(request))
     send_metric('origin:add', count=1, method_name='origin_add_one')
     return origin
 
 
 @app.route('/origin/visit/get', methods=['POST'])
 @timed
 def origin_visit_get():
     return encode_data(get_storage().origin_visit_get(
         **decode_request(request)))
 
 
 @app.route('/origin/visit/find_by_date', methods=['POST'])
 @timed
 def origin_visit_find_by_date():
     return encode_data(get_storage().origin_visit_find_by_date(
         **decode_request(request)))
 
 
 @app.route('/origin/visit/getby', methods=['POST'])
 @timed
 def origin_visit_get_by():
     return encode_data(
         get_storage().origin_visit_get_by(**decode_request(request)))
 
 
 @app.route('/origin/visit/get_latest', methods=['POST'])
 @timed
 def origin_visit_get_latest():
     return encode_data(
         get_storage().origin_visit_get_latest(**decode_request(request)))
 
 
 @app.route('/origin/visit/add', methods=['POST'])
 @timed
 @encode
 def origin_visit_add():
     origin_visit = get_storage().origin_visit_add(
         **decode_request(request))
     send_metric('origin_visit:add', count=1, method_name='origin_visit')
     return origin_visit
 
 
 @app.route('/origin/visit/update', methods=['POST'])
 @timed
 def origin_visit_update():
     return encode_data(get_storage().origin_visit_update(
         **decode_request(request)))
 
 
 @app.route('/origin/visit/upsert', methods=['POST'])
 @timed
 def origin_visit_upsert():
     return encode_data(get_storage().origin_visit_upsert(
         **decode_request(request)))
 
 
 @app.route('/fetch_history', methods=['GET'])
 @timed
 def fetch_history_get():
     return encode_data(get_storage().fetch_history_get(request.args['id']))
 
 
 @app.route('/fetch_history/start', methods=['POST'])
 @timed
 def fetch_history_start():
     return encode_data(
         get_storage().fetch_history_start(**decode_request(request)))
 
 
 @app.route('/fetch_history/end', methods=['POST'])
 @timed
 def fetch_history_end():
     return encode_data(
         get_storage().fetch_history_end(**decode_request(request)))
 
 
 @app.route('/tool/data', methods=['POST'])
 @timed
 def tool_get():
     return encode_data(get_storage().tool_get(
         **decode_request(request)))
 
 
 @app.route('/tool/add', methods=['POST'])
 @timed
 @encode
 def tool_add():
     tools = get_storage().tool_add(**decode_request(request))
     send_metric('tool:add', count=len(tools), method_name='tool_add')
     return tools
 
 
 @app.route('/origin/metadata/add', methods=['POST'])
 @timed
 @encode
 def origin_metadata_add():
     origin_metadata = get_storage().origin_metadata_add(
         **decode_request(request))
     send_metric(
         'origin_metadata:add', count=1, method_name='origin_metadata_add')
     return origin_metadata
 
 
 @app.route('/origin/metadata/get', methods=['POST'])
 @timed
 def origin_metadata_get_by():
     return encode_data(get_storage().origin_metadata_get_by(**decode_request(
                                                        request)))
 
 
 @app.route('/provider/add', methods=['POST'])
 @timed
 @encode
 def metadata_provider_add():
     metadata_provider = get_storage().metadata_provider_add(**decode_request(
         request))
     send_metric(
         'metadata_provider:add', count=1, method_name='metadata_provider')
     return metadata_provider
 
 
 @app.route('/provider/get', methods=['POST'])
 @timed
 def metadata_provider_get():
     return encode_data(get_storage().metadata_provider_get(**decode_request(
                                                        request)))
 
 
 @app.route('/provider/getby', methods=['POST'])
 @timed
 def metadata_provider_get_by():
     return encode_data(get_storage().metadata_provider_get_by(**decode_request(
                                                        request)))
 
 
 @app.route('/stat/counters', methods=['GET'])
 @timed
 def stat_counters():
     return encode_data(get_storage().stat_counters())
 
 
+@app.route('/stat/refresh', methods=['GET'])
+@timed
+def refresh_stat_counters():
+    return encode_data(get_storage().refresh_stat_counters())
+
+
 @app.route('/algos/diff_directories', methods=['POST'])
 @timed
 def diff_directories():
     return encode_data(get_storage().diff_directories(
         **decode_request(request)))
 
 
 @app.route('/algos/diff_revisions', methods=['POST'])
 @timed
 def diff_revisions():
     return encode_data(get_storage().diff_revisions(**decode_request(request)))
 
 
 @app.route('/algos/diff_revision', methods=['POST'])
 @timed
 def diff_revision():
     return encode_data(get_storage().diff_revision(**decode_request(request)))
 
 
 api_cfg = None
 
 
 def load_and_check_config(config_file, type='local'):
     """Check the minimal configuration is set to run the api or raise an
        error explanation.
 
     Args:
         config_file (str): Path to the configuration file to load
         type (str): configuration type. For 'local' type, more
                     checks are done.
 
     Raises:
         Error if the setup is not as expected
 
     Returns:
         configuration as a dict
 
     """
     if not config_file:
         raise EnvironmentError('Configuration file must be defined')
 
     if not os.path.exists(config_file):
         raise FileNotFoundError('Configuration file %s does not exist' % (
             config_file, ))
 
     cfg = config.read(config_file)
     if 'storage' not in cfg:
         raise KeyError("Missing '%storage' configuration")
 
     if type == 'local':
         vcfg = cfg['storage']
         cls = vcfg.get('cls')
         if cls != 'local':
             raise ValueError(
                 "The storage backend can only be started with a 'local' "
                 "configuration")
 
         args = vcfg['args']
         for key in ('db', 'objstorage'):
             if not args.get(key):
                 raise ValueError(
                     "Invalid configuration; missing '%s' config entry" % key)
 
     return cfg
 
 
 def make_app_from_configfile():
     """Run the WSGI app from the webserver, loading the configuration from
        a configuration file.
 
        SWH_CONFIG_FILENAME environment variable defines the
        configuration path to load.
 
     """
     global api_cfg
     if not api_cfg:
         config_file = os.environ.get('SWH_CONFIG_FILENAME')
         api_cfg = load_and_check_config(config_file)
         app.config.update(api_cfg)
     handler = logging.StreamHandler()
     app.logger.addHandler(handler)
     return app
 
 
 if __name__ == '__main__':
     print('Deprecated. Use swh-storage')
diff --git a/swh/storage/api/wsgi.py b/swh/storage/api/wsgi.py
deleted file mode 100644
index 02c4901f..00000000
--- a/swh/storage/api/wsgi.py
+++ /dev/null
@@ -1,8 +0,0 @@
-# Copyright (C) 2019  The Software Heritage developers
-# See the AUTHORS file at the top-level directory of this distribution
-# License: GNU General Public License version 3, or any later version
-# See top-level LICENSE file for more information
-
-from .server import make_app_from_configfile
-
-application = make_app_from_configfile()
diff --git a/swh/storage/in_memory.py b/swh/storage/in_memory.py
index 067fd882..74b10ac0 100644
--- a/swh/storage/in_memory.py
+++ b/swh/storage/in_memory.py
@@ -1,1748 +1,1748 @@
 # Copyright (C) 2015-2019  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import os
 import re
 import bisect
 import dateutil
 import collections
 from collections import defaultdict
 import copy
 import datetime
 import itertools
 import random
 
 import attr
 
 from swh.model.model import \
     Content, Directory, Revision, Release, Snapshot, OriginVisit, Origin
 from swh.model.hashutil import DEFAULT_ALGORITHMS
 from swh.objstorage import get_objstorage
 from swh.objstorage.exc import ObjNotFoundError
 
 from .storage import get_journal_writer
 
 # Max block size of contents to return
 BULK_BLOCK_CONTENT_LEN_MAX = 10000
 
 
 def now():
     return datetime.datetime.now(tz=datetime.timezone.utc)
 
 
 ENABLE_ORIGIN_IDS = \
     os.environ.get('SWH_STORAGE_IN_MEMORY_ENABLE_ORIGIN_IDS', 'true') == 'true'
 
 
 class Storage:
     def __init__(self, journal_writer=None):
         self._contents = {}
         self._content_indexes = defaultdict(lambda: defaultdict(set))
         self._skipped_contents = {}
         self._skipped_content_indexes = defaultdict(lambda: defaultdict(set))
 
         self.reset()
 
         if journal_writer:
             self.journal_writer = get_journal_writer(**journal_writer)
         else:
             self.journal_writer = None
 
     def reset(self):
         self._directories = {}
         self._revisions = {}
         self._releases = {}
         self._snapshots = {}
         self._origins = {}
         self._origins_by_id = []
         self._origin_visits = {}
         self._persons = []
         self._origin_metadata = defaultdict(list)
         self._tools = {}
         self._metadata_providers = {}
         self._objects = defaultdict(list)
 
         # ideally we would want a skip list for both fast inserts and searches
         self._sorted_sha1s = []
 
         self.objstorage = get_objstorage('memory', {})
 
     def check_config(self, *, check_write):
         """Check that the storage is configured and ready to go."""
         return True
 
     def _content_add(self, contents, with_data):
         content_with_data = []
         content_without_data = []
         for content in contents:
             if content.status is None:
                 content.status = 'visible'
             if content.length is None:
                 content.length = -1
-            if content.status == 'visible':
+            if content.status != 'absent':
                 if self._content_key(content) not in self._contents:
                     content_with_data.append(content)
-            elif content.status == 'absent':
+            else:
                 if self._content_key(content) not in self._skipped_contents:
                     content_without_data.append(content)
 
         if self.journal_writer:
             for content in content_with_data:
                 content = attr.evolve(content, data=None)
                 self.journal_writer.write_addition('content', content)
             for content in content_without_data:
                 self.journal_writer.write_addition('content', content)
 
         count_content_added, count_content_bytes_added = \
             self._content_add_present(content_with_data, with_data)
 
         count_skipped_content_added = self._content_add_absent(
             content_without_data
         )
 
         summary = {
             'content:add': count_content_added,
             'skipped_content:add': count_skipped_content_added,
         }
 
         if with_data:
             summary['content:add:bytes'] = count_content_bytes_added
 
         return summary
 
     def _content_add_present(self, contents, with_data):
         count_content_added = 0
         count_content_bytes_added = 0
         for content in contents:
             key = self._content_key(content)
             if key in self._contents:
                 continue
             for algorithm in DEFAULT_ALGORITHMS:
                 hash_ = content.get_hash(algorithm)
                 if hash_ in self._content_indexes[algorithm]\
                    and (algorithm not in {'blake2s256', 'sha256'}):
                     from . import HashCollision
                     raise HashCollision(algorithm, hash_, key)
             for algorithm in DEFAULT_ALGORITHMS:
                 hash_ = content.get_hash(algorithm)
                 self._content_indexes[algorithm][hash_].add(key)
             self._objects[content.sha1_git].append(
                 ('content', content.sha1))
             self._contents[key] = content
             bisect.insort(self._sorted_sha1s, content.sha1)
             count_content_added += 1
             if with_data:
                 content_data = self._contents[key].data
                 self._contents[key].data = None
                 count_content_bytes_added += len(content_data)
                 self.objstorage.add(content_data, content.sha1)
 
         return (count_content_added, count_content_bytes_added)
 
     def _content_add_absent(self, contents):
         count = 0
         skipped_content_missing = self.skipped_content_missing(contents)
         for content in skipped_content_missing:
             key = self._content_key(content)
             for algo in DEFAULT_ALGORITHMS:
                 self._skipped_content_indexes[algo][content.get_hash(algo)] \
                     .add(key)
             self._skipped_contents[key] = content
             count += 1
 
         return count
 
     def _content_to_model(self, contents):
         """Takes a list of content dicts, optionally with an extra 'origin'
         key, and yields tuples (model.Content, origin)."""
         for content in contents:
             content = content.copy()
             content.pop('origin', None)
             yield Content.from_dict(content)
 
     def content_add(self, content):
         """Add content blobs to the storage
 
         Args:
             content (iterable): iterable of dictionaries representing
                 individual pieces of content to add. Each dictionary has the
                 following keys:
 
                 - data (bytes): the actual content
                 - length (int): content length (default: -1)
                 - one key for each checksum algorithm in
                   :data:`swh.model.hashutil.DEFAULT_ALGORITHMS`, mapped to the
                   corresponding checksum
                 - status (str): one of visible, hidden, absent
                 - reason (str): if status = absent, the reason why
                 - origin (int): if status = absent, the origin we saw the
                   content in
 
         Raises:
             HashCollision in case of collision
 
         Returns:
             Summary dict with the following key and associated values:
 
                 content:add: New contents added
                 content_bytes:add: Sum of the contents' length data
                 skipped_content:add: New skipped contents (no data) added
 
         """
         content = list(self._content_to_model(content))
         now = datetime.datetime.now(tz=datetime.timezone.utc)
         for item in content:
             item.ctime = now
         return self._content_add(content, with_data=True)
 
     def content_add_metadata(self, content):
         """Add content metadata to the storage (like `content_add`, but
         without inserting to the objstorage).
 
         Args:
             content (iterable): iterable of dictionaries representing
                 individual pieces of content to add. Each dictionary has the
                 following keys:
 
                 - length (int): content length (default: -1)
                 - one key for each checksum algorithm in
                   :data:`swh.model.hashutil.DEFAULT_ALGORITHMS`, mapped to the
                   corresponding checksum
                 - status (str): one of visible, hidden, absent
                 - reason (str): if status = absent, the reason why
                 - origin (int): if status = absent, the origin we saw the
                   content in
                 - ctime (datetime): time of insertion in the archive
 
         Raises:
             HashCollision in case of collision
 
         Returns:
             Summary dict with the following key and associated values:
 
                 content:add: New contents added
                 skipped_content:add: New skipped contents (no data) added
 
         """
         content = list(self._content_to_model(content))
         return self._content_add(content, with_data=False)
 
     def content_get(self, content):
         """Retrieve in bulk contents and their data.
 
         This function may yield more blobs than provided sha1 identifiers,
         in case they collide.
 
         Args:
             content: iterables of sha1
 
         Yields:
             Dict[str, bytes]: Generates streams of contents as dict with their
                 raw data:
 
                 - sha1 (bytes): content id
                 - data (bytes): content's raw data
 
         Raises:
             ValueError in case of too much contents are required.
             cf. BULK_BLOCK_CONTENT_LEN_MAX
 
         """
         # FIXME: Make this method support slicing the `data`.
         if len(content) > BULK_BLOCK_CONTENT_LEN_MAX:
             raise ValueError(
                 "Sending at most %s contents." % BULK_BLOCK_CONTENT_LEN_MAX)
         for obj_id in content:
             try:
                 data = self.objstorage.get(obj_id)
             except ObjNotFoundError:
                 yield None
                 continue
 
             yield {'sha1': obj_id, 'data': data}
 
     def content_get_range(self, start, end, limit=1000, db=None, cur=None):
         """Retrieve contents within range [start, end] bound by limit.
 
         Note that this function may return more than one blob per hash. The
         limit is enforced with multiplicity (ie. two blobs with the same hash
         will count twice toward the limit).
 
         Args:
             **start** (bytes): Starting identifier range (expected smaller
                            than end)
             **end** (bytes): Ending identifier range (expected larger
                              than start)
             **limit** (int): Limit result (default to 1000)
 
         Returns:
             a dict with keys:
             - contents [dict]: iterable of contents in between the range.
             - next (bytes): There remains content in the range
               starting from this next sha1
 
         """
         if limit is None:
             raise ValueError('Development error: limit should not be None')
         from_index = bisect.bisect_left(self._sorted_sha1s, start)
         sha1s = itertools.islice(self._sorted_sha1s, from_index, None)
         sha1s = ((sha1, content_key)
                  for sha1 in sha1s
                  for content_key in self._content_indexes['sha1'][sha1])
         matched = []
         next_content = None
         for sha1, key in sha1s:
             if sha1 > end:
                 break
             if len(matched) >= limit:
                 next_content = sha1
                 break
             matched.append(self._contents[key].to_dict())
         return {
             'contents': matched,
             'next': next_content,
         }
 
     def content_get_metadata(self, content):
         """Retrieve content metadata in bulk
 
         Args:
             content: iterable of content identifiers (sha1)
 
         Returns:
             an iterable with content metadata corresponding to the given ids
         """
         # FIXME: the return value should be a mapping from search key to found
         # content*s*
         for sha1 in content:
             if sha1 in self._content_indexes['sha1']:
                 objs = self._content_indexes['sha1'][sha1]
                 # FIXME: rather than selecting one of the objects with that
                 # hash, we should return all of them. See:
                 # https://forge.softwareheritage.org/D645?id=1994#inline-3389
                 key = random.sample(objs, 1)[0]
                 d = self._contents[key].to_dict()
                 del d['ctime']
                 yield d
             else:
                 # FIXME: should really be None
                 yield {
                     'sha1': sha1,
                     'sha1_git': None,
                     'sha256': None,
                     'blake2s256': None,
                     'length': None,
                     'status': None,
                 }
 
     def content_find(self, content):
         if not set(content).intersection(DEFAULT_ALGORITHMS):
             raise ValueError('content keys must contain at least one of: '
                              '%s' % ', '.join(sorted(DEFAULT_ALGORITHMS)))
         found = []
         for algo in DEFAULT_ALGORITHMS:
             hash = content.get(algo)
             if hash and hash in self._content_indexes[algo]:
                 found.append(self._content_indexes[algo][hash])
 
         if not found:
             return []
 
         keys = list(set.intersection(*found))
         return [self._contents[key].to_dict() for key in keys]
 
     def content_missing(self, content, key_hash='sha1'):
         """List content missing from storage
 
         Args:
             contents ([dict]): iterable of dictionaries whose keys are
                                either 'length' or an item of
                                :data:`swh.model.hashutil.ALGORITHMS`;
                                mapped to the corresponding checksum
                                (or length).
 
             key_hash (str): name of the column to use as hash id
                             result (default: 'sha1')
 
         Returns:
             iterable ([bytes]): missing content ids (as per the
             key_hash column)
         """
         for cont in content:
             for (algo, hash_) in cont.items():
                 if algo not in DEFAULT_ALGORITHMS:
                     continue
                 if hash_ not in self._content_indexes.get(algo, []):
                     yield cont[key_hash]
                     break
             else:
                 for result in self.content_find(cont):
                     if result['status'] == 'missing':
                         yield cont[key_hash]
 
     def content_missing_per_sha1(self, contents):
         """List content missing from storage based only on sha1.
 
         Args:
             contents: Iterable of sha1 to check for absence.
 
         Returns:
             iterable: missing ids
 
         Raises:
             TODO: an exception when we get a hash collision.
 
         """
         for content in contents:
             if content not in self._content_indexes['sha1']:
                 yield content
 
     def skipped_content_missing(self, contents):
         """List all skipped_content missing from storage
 
         Args:
             contents: Iterable of sha1 to check for skipped content entry
 
         Returns:
             iterable: dict of skipped content entry
         """
 
         for content in contents:
             for (key, algorithm) in self._content_key_algorithm(content):
                 if algorithm == 'blake2s256':
                     continue
                 if key not in self._skipped_content_indexes[algorithm]:
                     # index must contain hashes of algos except blake2s256
                     # else the content is considered skipped
                     yield content
                     break
 
     def directory_add(self, directories):
         """Add directories to the storage
 
         Args:
             directories (iterable): iterable of dictionaries representing the
                 individual directories to add. Each dict has the following
                 keys:
 
                 - id (sha1_git): the id of the directory to add
                 - entries (list): list of dicts for each entry in the
                       directory.  Each dict has the following keys:
 
                       - name (bytes)
                       - type (one of 'file', 'dir', 'rev'): type of the
                         directory entry (file, directory, revision)
                       - target (sha1_git): id of the object pointed at by the
                         directory entry
                       - perms (int): entry permissions
         Returns:
             Summary dict of keys with associated count as values:
 
                 directory:add: Number of directories actually added
 
         """
         if self.journal_writer:
             self.journal_writer.write_additions(
                 'directory',
                 (dir_ for dir_ in directories
                  if dir_['id'] not in self._directories))
 
         directories = [Directory.from_dict(d) for d in directories]
 
         count = 0
         for directory in directories:
             if directory.id not in self._directories:
                 count += 1
                 self._directories[directory.id] = directory
                 self._objects[directory.id].append(
                     ('directory', directory.id))
 
         return {'directory:add': count}
 
     def directory_missing(self, directories):
         """List directories missing from storage
 
         Args:
             directories (iterable): an iterable of directory ids
 
         Yields:
             missing directory ids
 
         """
         for id in directories:
             if id not in self._directories:
                 yield id
 
     def _join_dentry_to_content(self, dentry):
         keys = (
             'status',
             'sha1',
             'sha1_git',
             'sha256',
             'length',
         )
         ret = dict.fromkeys(keys)
         ret.update(dentry)
         if ret['type'] == 'file':
             # TODO: Make it able to handle more than one content
             content = self.content_find({'sha1_git': ret['target']})
             if content:
                 content = content[0]
                 for key in keys:
                     ret[key] = content[key]
         return ret
 
     def _directory_ls(self, directory_id, recursive, prefix=b''):
         if directory_id in self._directories:
             for entry in self._directories[directory_id].entries:
                 ret = self._join_dentry_to_content(entry.to_dict())
                 ret['name'] = prefix + ret['name']
                 ret['dir_id'] = directory_id
                 yield ret
                 if recursive and ret['type'] == 'dir':
                     yield from self._directory_ls(
                         ret['target'], True, prefix + ret['name'] + b'/')
 
     def directory_ls(self, directory, recursive=False):
         """Get entries for one directory.
 
         Args:
             - directory: the directory to list entries from.
             - recursive: if flag on, this list recursively from this directory.
 
         Returns:
             List of entries for such directory.
 
         If `recursive=True`, names in the path of a dir/file not at the
         root are concatenated with a slash (`/`).
         """
         yield from self._directory_ls(directory, recursive)
 
     def directory_entry_get_by_path(self, directory, paths):
         """Get the directory entry (either file or dir) from directory with path.
 
         Args:
             - directory: sha1 of the top level directory
             - paths: path to lookup from the top level directory. From left
               (top) to right (bottom).
 
         Returns:
             The corresponding directory entry if found, None otherwise.
 
         """
         return self._directory_entry_get_by_path(directory, paths, b'')
 
     def _directory_entry_get_by_path(self, directory, paths, prefix):
         if not paths:
             return
 
         contents = list(self.directory_ls(directory))
 
         if not contents:
             return
 
         def _get_entry(entries, name):
             for entry in entries:
                 if entry['name'] == name:
                     entry = entry.copy()
                     entry['name'] = prefix + entry['name']
                     return entry
 
         first_item = _get_entry(contents, paths[0])
 
         if len(paths) == 1:
             return first_item
 
         if not first_item or first_item['type'] != 'dir':
             return
 
         return self._directory_entry_get_by_path(
                 first_item['target'], paths[1:], prefix + paths[0] + b'/')
 
     def revision_add(self, revisions):
         """Add revisions to the storage
 
         Args:
             revisions (Iterable[dict]): iterable of dictionaries representing
                 the individual revisions to add. Each dict has the following
                 keys:
 
                 - **id** (:class:`sha1_git`): id of the revision to add
                 - **date** (:class:`dict`): date the revision was written
                 - **committer_date** (:class:`dict`): date the revision got
                   added to the origin
                 - **type** (one of 'git', 'tar'): type of the
                   revision added
                 - **directory** (:class:`sha1_git`): the directory the
                   revision points at
                 - **message** (:class:`bytes`): the message associated with
                   the revision
                 - **author** (:class:`Dict[str, bytes]`): dictionary with
                   keys: name, fullname, email
                 - **committer** (:class:`Dict[str, bytes]`): dictionary with
                   keys: name, fullname, email
                 - **metadata** (:class:`jsonb`): extra information as
                   dictionary
                 - **synthetic** (:class:`bool`): revision's nature (tarball,
                   directory creates synthetic revision`)
                 - **parents** (:class:`list[sha1_git]`): the parents of
                   this revision
 
         date dictionaries have the form defined in :mod:`swh.model`.
 
         Returns:
             Summary dict of keys with associated count as values
 
                 revision_added: New objects actually stored in db
 
         """
         if self.journal_writer:
             self.journal_writer.write_additions(
                 'revision',
                 (rev for rev in revisions
                  if rev['id'] not in self._revisions))
 
         revisions = [Revision.from_dict(rev) for rev in revisions]
 
         count = 0
         for revision in revisions:
             if revision.id not in self._revisions:
                 revision.committer = self._person_add(revision.committer)
                 revision.author = self._person_add(revision.author)
                 self._revisions[revision.id] = revision
                 self._objects[revision.id].append(
                     ('revision', revision.id))
                 count += 1
 
         return {'revision:add': count}
 
     def revision_missing(self, revisions):
         """List revisions missing from storage
 
         Args:
             revisions (iterable): revision ids
 
         Yields:
             missing revision ids
 
         """
         for id in revisions:
             if id not in self._revisions:
                 yield id
 
     def revision_get(self, revisions):
         for id in revisions:
             if id in self._revisions:
                 yield self._revisions.get(id).to_dict()
             else:
                 yield None
 
     def _get_parent_revs(self, rev_id, seen, limit):
         if limit and len(seen) >= limit:
             return
         if rev_id in seen or rev_id not in self._revisions:
             return
         seen.add(rev_id)
         yield self._revisions[rev_id].to_dict()
         for parent in self._revisions[rev_id].parents:
             yield from self._get_parent_revs(parent, seen, limit)
 
     def revision_log(self, revisions, limit=None):
         """Fetch revision entry from the given root revisions.
 
         Args:
             revisions: array of root revision to lookup
             limit: limitation on the output result. Default to None.
 
         Yields:
             List of revision log from such revisions root.
 
         """
         seen = set()
         for rev_id in revisions:
             yield from self._get_parent_revs(rev_id, seen, limit)
 
     def revision_shortlog(self, revisions, limit=None):
         """Fetch the shortlog for the given revisions
 
         Args:
             revisions: list of root revisions to lookup
             limit: depth limitation for the output
 
         Yields:
             a list of (id, parents) tuples.
 
         """
         yield from ((rev['id'], rev['parents'])
                     for rev in self.revision_log(revisions, limit))
 
     def release_add(self, releases):
         """Add releases to the storage
 
         Args:
             releases (Iterable[dict]): iterable of dictionaries representing
                 the individual releases to add. Each dict has the following
                 keys:
 
                 - **id** (:class:`sha1_git`): id of the release to add
                 - **revision** (:class:`sha1_git`): id of the revision the
                   release points to
                 - **date** (:class:`dict`): the date the release was made
                 - **name** (:class:`bytes`): the name of the release
                 - **comment** (:class:`bytes`): the comment associated with
                   the release
                 - **author** (:class:`Dict[str, bytes]`): dictionary with
                   keys: name, fullname, email
 
         the date dictionary has the form defined in :mod:`swh.model`.
 
         Returns:
             Summary dict of keys with associated count as values
 
                 release:add: New objects contents actually stored in db
 
         """
         if self.journal_writer:
             self.journal_writer.write_additions(
                 'release',
                 (rel for rel in releases
                  if rel['id'] not in self._releases))
 
         releases = [Release.from_dict(rel) for rel in releases]
 
         count = 0
         for rel in releases:
             if rel.id not in self._releases:
                 if rel.author:
                     self._person_add(rel.author)
                 self._objects[rel.id].append(
                     ('release', rel.id))
                 self._releases[rel.id] = rel
                 count += 1
 
         return {'release:add': count}
 
     def release_missing(self, releases):
         """List releases missing from storage
 
         Args:
             releases: an iterable of release ids
 
         Returns:
             a list of missing release ids
 
         """
         yield from (rel for rel in releases if rel not in self._releases)
 
     def release_get(self, releases):
         """Given a list of sha1, return the releases's information
 
         Args:
             releases: list of sha1s
 
         Yields:
             dicts with the same keys as those given to `release_add`
             (or ``None`` if a release does not exist)
 
         """
         for rel_id in releases:
             if rel_id in self._releases:
                 yield self._releases[rel_id].to_dict()
             else:
                 yield None
 
     def snapshot_add(self, snapshots):
         """Add a snapshot to the storage
 
         Args:
             snapshot ([dict]): the snapshots to add, containing the
               following keys:
 
               - **id** (:class:`bytes`): id of the snapshot
               - **branches** (:class:`dict`): branches the snapshot contains,
                 mapping the branch name (:class:`bytes`) to the branch target,
                 itself a :class:`dict` (or ``None`` if the branch points to an
                 unknown object)
 
                 - **target_type** (:class:`str`): one of ``content``,
                   ``directory``, ``revision``, ``release``,
                   ``snapshot``, ``alias``
                 - **target** (:class:`bytes`): identifier of the target
                   (currently a ``sha1_git`` for all object kinds, or the name
                   of the target branch for aliases)
 
         Raises:
             ValueError: if the origin's or visit's identifier does not exist.
 
         Returns:
             Summary dict of keys with associated count as values
 
                 snapshot_added: Count of object actually stored in db
 
         """
         count = 0
         snapshots = (Snapshot.from_dict(d) for d in snapshots)
         snapshots = (snap for snap in snapshots
                      if snap.id not in self._snapshots)
         for snapshot in snapshots:
             if self.journal_writer:
                 self.journal_writer.write_addition('snapshot', snapshot)
 
             sorted_branch_names = sorted(snapshot.branches)
             self._snapshots[snapshot.id] = (snapshot, sorted_branch_names)
             self._objects[snapshot.id].append(('snapshot', snapshot.id))
             count += 1
 
         return {'snapshot:add': count}
 
     def snapshot_get(self, snapshot_id):
         """Get the content, possibly partial, of a snapshot with the given id
 
         The branches of the snapshot are iterated in the lexicographical
         order of their names.
 
         .. warning:: At most 1000 branches contained in the snapshot will be
             returned for performance reasons. In order to browse the whole
             set of branches, the method :meth:`snapshot_get_branches`
             should be used instead.
 
         Args:
             snapshot_id (bytes): identifier of the snapshot
         Returns:
             dict: a dict with three keys:
                 * **id**: identifier of the snapshot
                 * **branches**: a dict of branches contained in the snapshot
                   whose keys are the branches' names.
                 * **next_branch**: the name of the first branch not returned
                   or :const:`None` if the snapshot has less than 1000
                   branches.
         """
         return self.snapshot_get_branches(snapshot_id)
 
     def snapshot_get_by_origin_visit(self, origin, visit):
         """Get the content, possibly partial, of a snapshot for the given origin visit
 
         The branches of the snapshot are iterated in the lexicographical
         order of their names.
 
         .. warning:: At most 1000 branches contained in the snapshot will be
             returned for performance reasons. In order to browse the whole
             set of branches, the method :meth:`snapshot_get_branches`
             should be used instead.
 
         Args:
             origin (int): the origin's identifier
             visit (int): the visit's identifier
         Returns:
             dict: None if the snapshot does not exist;
               a dict with three keys otherwise:
                 * **id**: identifier of the snapshot
                 * **branches**: a dict of branches contained in the snapshot
                   whose keys are the branches' names.
                 * **next_branch**: the name of the first branch not returned
                   or :const:`None` if the snapshot has less than 1000
                   branches.
 
         """
         origin_url = self._get_origin_url(origin)
         if not origin_url:
             return
 
         if origin_url not in self._origins or \
            visit > len(self._origin_visits[origin_url]):
             return None
         snapshot_id = self._origin_visits[origin_url][visit-1].snapshot
         if snapshot_id:
             return self.snapshot_get(snapshot_id)
         else:
             return None
 
     def snapshot_get_latest(self, origin, allowed_statuses=None):
         """Get the content, possibly partial, of the latest snapshot for the
         given origin, optionally only from visits that have one of the given
         allowed_statuses
 
         The branches of the snapshot are iterated in the lexicographical
         order of their names.
 
         .. warning:: At most 1000 branches contained in the snapshot will be
             returned for performance reasons. In order to browse the whole
             set of branches, the methods :meth:`origin_visit_get_latest`
             and :meth:`snapshot_get_branches` should be used instead.
 
         Args:
             origin (Union[str,int]): the origin's URL or identifier
             allowed_statuses (list of str): list of visit statuses considered
                 to find the latest snapshot for the origin. For instance,
                 ``allowed_statuses=['full']`` will only consider visits that
                 have successfully run to completion.
         Returns:
             dict: a dict with three keys:
                 * **id**: identifier of the snapshot
                 * **branches**: a dict of branches contained in the snapshot
                   whose keys are the branches' names.
                 * **next_branch**: the name of the first branch not returned
                   or :const:`None` if the snapshot has less than 1000
                   branches.
         """
         origin_url = self._get_origin_url(origin)
         if not origin_url:
             return
 
         visit = self.origin_visit_get_latest(
             origin_url,
             allowed_statuses=allowed_statuses,
             require_snapshot=True)
         if visit and visit['snapshot']:
             snapshot = self.snapshot_get(visit['snapshot'])
             if not snapshot:
                 raise ValueError(
                     'last origin visit references an unknown snapshot')
             return snapshot
 
     def snapshot_count_branches(self, snapshot_id, db=None, cur=None):
         """Count the number of branches in the snapshot with the given id
 
         Args:
             snapshot_id (bytes): identifier of the snapshot
 
         Returns:
             dict: A dict whose keys are the target types of branches and
             values their corresponding amount
         """
         (snapshot, _) = self._snapshots[snapshot_id]
         return collections.Counter(branch.target_type.value if branch else None
                                    for branch in snapshot.branches.values())
 
     def snapshot_get_branches(self, snapshot_id, branches_from=b'',
                               branches_count=1000, target_types=None):
         """Get the content, possibly partial, of a snapshot with the given id
 
         The branches of the snapshot are iterated in the lexicographical
         order of their names.
 
         Args:
             snapshot_id (bytes): identifier of the snapshot
             branches_from (bytes): optional parameter used to skip branches
                 whose name is lesser than it before returning them
             branches_count (int): optional parameter used to restrain
                 the amount of returned branches
             target_types (list): optional parameter used to filter the
                 target types of branch to return (possible values that can be
                 contained in that list are `'content', 'directory',
                 'revision', 'release', 'snapshot', 'alias'`)
         Returns:
             dict: None if the snapshot does not exist;
               a dict with three keys otherwise:
                 * **id**: identifier of the snapshot
                 * **branches**: a dict of branches contained in the snapshot
                   whose keys are the branches' names.
                 * **next_branch**: the name of the first branch not returned
                   or :const:`None` if the snapshot has less than
                   `branches_count` branches after `branches_from` included.
         """
         res = self._snapshots.get(snapshot_id)
         if res is None:
             return None
         (snapshot, sorted_branch_names) = res
         from_index = bisect.bisect_left(
                 sorted_branch_names, branches_from)
         if target_types:
             next_branch = None
             branches = {}
             for branch_name in sorted_branch_names[from_index:]:
                 branch = snapshot.branches[branch_name]
                 if branch and branch.target_type.value in target_types:
                     if len(branches) < branches_count:
                         branches[branch_name] = branch
                     else:
                         next_branch = branch_name
                         break
         else:
             # As there is no 'target_types', we can do that much faster
             to_index = from_index + branches_count
             returned_branch_names = sorted_branch_names[from_index:to_index]
             branches = {branch_name: snapshot.branches[branch_name]
                         for branch_name in returned_branch_names}
             if to_index >= len(sorted_branch_names):
                 next_branch = None
             else:
                 next_branch = sorted_branch_names[to_index]
 
         branches = {name: branch.to_dict() if branch else None
                     for (name, branch) in branches.items()}
 
         return {
                 'id': snapshot_id,
                 'branches': branches,
                 'next_branch': next_branch,
                 }
 
     def object_find_by_sha1_git(self, ids, db=None, cur=None):
         """Return the objects found with the given ids.
 
         Args:
             ids: a generator of sha1_gits
 
         Returns:
             dict: a mapping from id to the list of objects found. Each object
             found is itself a dict with keys:
 
             - sha1_git: the input id
             - type: the type of object found
             - id: the id of the object found
             - object_id: the numeric id of the object found.
 
         """
         ret = {}
         for id_ in ids:
             objs = self._objects.get(id_, [])
             ret[id_] = [{
                     'sha1_git': id_,
                     'type': obj[0],
                     'id': obj[1],
                     'object_id': id_,
                     } for obj in objs]
         return ret
 
     def _convert_origin(self, t):
         if t is None:
             return None
         (origin_id, origin) = t
         origin = origin.to_dict()
         if ENABLE_ORIGIN_IDS:
             origin['id'] = origin_id
         return origin
 
     def origin_get(self, origins):
         """Return origins, either all identified by their ids or all
         identified by tuples (type, url).
 
         If the url is given and the type is omitted, one of the origins with
         that url is returned.
 
         Args:
             origin: a list of dictionaries representing the individual
                 origins to find.
                 These dicts have either the key url (and optionally type):
 
                 - type (FIXME: enum TBD): the origin type ('git', 'wget', ...)
                 - url (bytes): the url the origin points to
 
                 or the id:
 
                 - id (int): the origin's identifier
 
         Returns:
             dict: the origin dictionary with the keys:
 
             - id: origin's id
             - type: origin's type
             - url: origin's url
 
         Raises:
             ValueError: if the keys does not match (url and type) nor id.
 
         """
         if isinstance(origins, dict):
             # Old API
             return_single = True
             origins = [origins]
         else:
             return_single = False
 
         # Sanity check to be error-compatible with the pgsql backend
         if any('id' in origin for origin in origins) \
                 and not all('id' in origin for origin in origins):
             raise ValueError(
                 'Either all origins or none at all should have an "id".')
         if any('url' in origin for origin in origins) \
                 and not all('url' in origin for origin in origins):
             raise ValueError(
                 'Either all origins or none at all should have '
                 'an "url" key.')
 
         results = []
         for origin in origins:
             result = None
             if 'id' in origin:
                 assert ENABLE_ORIGIN_IDS, 'origin ids are disabled'
                 if origin['id'] <= len(self._origins_by_id):
                     result = self._origins[self._origins_by_id[origin['id']-1]]
             elif 'url' in origin:
                 if origin['url'] in self._origins:
                     result = self._origins[origin['url']]
             else:
                 raise ValueError(
                     'Origin must have either id or url.')
             results.append(self._convert_origin(result))
 
         if return_single:
             assert len(results) == 1
             return results[0]
         else:
             return results
 
     def origin_get_range(self, origin_from=1, origin_count=100):
         """Retrieve ``origin_count`` origins whose ids are greater
         or equal than ``origin_from``.
 
         Origins are sorted by id before retrieving them.
 
         Args:
             origin_from (int): the minimum id of origins to retrieve
             origin_count (int): the maximum number of origins to retrieve
 
         Yields:
             dicts containing origin information as returned
             by :meth:`swh.storage.in_memory.Storage.origin_get`.
         """
         origin_from = max(origin_from, 1)
         if origin_from <= len(self._origins_by_id):
             max_idx = origin_from + origin_count - 1
             if max_idx > len(self._origins_by_id):
                 max_idx = len(self._origins_by_id)
             for idx in range(origin_from-1, max_idx):
                 yield self._convert_origin(
                     self._origins[self._origins_by_id[idx]])
 
     def origin_search(self, url_pattern, offset=0, limit=50,
                       regexp=False, with_visit=False, db=None, cur=None):
         """Search for origins whose urls contain a provided string pattern
         or match a provided regular expression.
         The search is performed in a case insensitive way.
 
         Args:
             url_pattern (str): the string pattern to search for in origin urls
             offset (int): number of found origins to skip before returning
                 results
             limit (int): the maximum number of found origins to return
             regexp (bool): if True, consider the provided pattern as a regular
                 expression and return origins whose urls match it
             with_visit (bool): if True, filter out origins with no visit
 
         Returns:
             An iterable of dict containing origin information as returned
             by :meth:`swh.storage.storage.Storage.origin_get`.
         """
         origins = map(self._convert_origin, self._origins.values())
         if regexp:
             pat = re.compile(url_pattern)
             origins = [orig for orig in origins if pat.search(orig['url'])]
         else:
             origins = [orig for orig in origins if url_pattern in orig['url']]
         if with_visit:
             origins = [orig for orig in origins
                        if len(self._origin_visits[orig['url']]) > 0]
 
         if ENABLE_ORIGIN_IDS:
             origins.sort(key=lambda origin: origin['id'])
 
         return origins[offset:offset+limit]
 
     def origin_count(self, url_pattern, regexp=False, with_visit=False,
                      db=None, cur=None):
         """Count origins whose urls contain a provided string pattern
         or match a provided regular expression.
         The pattern search in origin urls is performed in a case insensitive
         way.
 
         Args:
             url_pattern (str): the string pattern to search for in origin urls
             regexp (bool): if True, consider the provided pattern as a regular
                 expression and return origins whose urls match it
             with_visit (bool): if True, filter out origins with no visit
 
         Returns:
             int: The number of origins matching the search criterion.
         """
         return len(self.origin_search(url_pattern, regexp=regexp,
                                       with_visit=with_visit,
                                       limit=len(self._origins)))
 
     def origin_add(self, origins):
         """Add origins to the storage
 
         Args:
             origins: list of dictionaries representing the individual origins,
                 with the following keys:
 
                 - type: the origin type ('git', 'svn', 'deb', ...)
                 - url (bytes): the url the origin points to
 
         Returns:
             list: given origins as dict updated with their id
 
         """
         origins = copy.deepcopy(origins)
         for origin in origins:
             if ENABLE_ORIGIN_IDS:
                 origin['id'] = self.origin_add_one(origin)
             else:
                 self.origin_add_one(origin)
         return origins
 
     def origin_add_one(self, origin):
         """Add origin to the storage
 
         Args:
             origin: dictionary representing the individual origin to add. This
                 dict has the following keys:
 
                 - type (FIXME: enum TBD): the origin type ('git', 'wget', ...)
                 - url (bytes): the url the origin points to
 
         Returns:
             the id of the added origin, or of the identical one that already
             exists.
 
         """
         origin = Origin.from_dict(origin)
         if origin.url in self._origins:
             if ENABLE_ORIGIN_IDS:
                 (origin_id, _) = self._origins[origin.url]
         else:
             if self.journal_writer:
                 self.journal_writer.write_addition('origin', origin)
             if ENABLE_ORIGIN_IDS:
                 # origin ids are in the range [1, +inf[
                 origin_id = len(self._origins) + 1
                 self._origins_by_id.append(origin.url)
                 assert len(self._origins_by_id) == origin_id
             else:
                 origin_id = None
             self._origins[origin.url] = (origin_id, origin)
             self._origin_visits[origin.url] = []
             self._objects[origin.url].append(('origin', origin.url))
 
         if ENABLE_ORIGIN_IDS:
             return origin_id
         else:
             return origin.url
 
     def fetch_history_start(self, origin_id):
         """Add an entry for origin origin_id in fetch_history. Returns the id
         of the added fetch_history entry
         """
         assert not ENABLE_ORIGIN_IDS, 'origin ids are disabled'
         pass
 
     def fetch_history_end(self, fetch_history_id, data):
         """Close the fetch_history entry with id `fetch_history_id`, replacing
            its data with `data`.
         """
         pass
 
     def fetch_history_get(self, fetch_history_id):
         """Get the fetch_history entry with id `fetch_history_id`.
         """
         raise NotImplementedError('fetch_history_get is deprecated, use '
                                   'origin_visit_get instead.')
 
     def origin_visit_add(self, origin, date, type=None):
         """Add an origin_visit for the origin at date with status 'ongoing'.
 
         For backward compatibility, `type` is optional and defaults to
         the origin's type.
 
         Args:
             origin (Union[int,str]): visited origin's identifier or URL
             date (Union[str,datetime]): timestamp of such visit
             type (str): the type of loader used for the visit (hg, git, ...)
 
         Returns:
             dict: dictionary with keys origin and visit where:
 
             - origin: origin's identifier
             - visit: the visit's identifier for the new visit occurrence
 
         """
         origin_url = self._get_origin_url(origin)
         if origin_url is None:
             raise ValueError('Unknown origin.')
 
         if isinstance(date, str):
             # FIXME: Converge on iso8601 at some point
             date = dateutil.parser.parse(date)
         elif not isinstance(date, datetime.datetime):
             raise TypeError('date must be a datetime or a string.')
 
         visit_ret = None
         if origin_url in self._origins:
             (origin_id, origin) = self._origins[origin_url]
             # visit ids are in the range [1, +inf[
             visit_id = len(self._origin_visits[origin_url]) + 1
             status = 'ongoing'
             visit = OriginVisit(
                 origin=origin,
                 date=date,
                 type=type or origin.type,
                 status=status,
                 snapshot=None,
                 metadata=None,
                 visit=visit_id,
             )
             self._origin_visits[origin_url].append(visit)
             visit_ret = {
                 'origin': origin_id if ENABLE_ORIGIN_IDS else origin.url,
                 'visit': visit_id,
             }
 
             self._objects[(origin_url, visit_id)].append(
                 ('origin_visit', None))
 
             if self.journal_writer:
                 self.journal_writer.write_addition('origin_visit', visit)
 
         return visit_ret
 
     def origin_visit_update(self, origin, visit_id, status=None,
                             metadata=None, snapshot=None):
         """Update an origin_visit's status.
 
         Args:
             origin (Union[int,str]): visited origin's identifier or URL
             visit_id (int): visit's identifier
             status: visit's new status
             metadata: data associated to the visit
             snapshot (sha1_git): identifier of the snapshot to add to
                 the visit
 
         Returns:
             None
 
         """
         origin_url = self._get_origin_url(origin)
         if origin_url is None:
             raise ValueError('Unknown origin.')
 
         try:
             visit = self._origin_visits[origin_url][visit_id-1]
         except IndexError:
             raise ValueError('Unknown visit_id for this origin') \
                 from None
 
         updates = {}
         if status:
             updates['status'] = status
         if metadata:
             updates['metadata'] = metadata
         if snapshot:
             updates['snapshot'] = snapshot
 
         visit = attr.evolve(visit, **updates)
 
         if self.journal_writer:
             (_, origin) = self._origins[origin_url]
             self.journal_writer.write_update('origin_visit', visit)
 
         self._origin_visits[origin_url][visit_id-1] = visit
 
         if origin_url not in self._origin_visits or \
                 visit_id > len(self._origin_visits[origin_url]):
             return
 
     def origin_visit_upsert(self, visits):
         """Add a origin_visits with a specific id and with all its data.
         If there is already an origin_visit with the same
         `(origin_url, visit_id)`, updates it instead of inserting a new one.
 
         Args:
             visits: iterable of dicts with keys:
 
                 origin: dict with keys either `id` or `url`
                 visit: origin visit id
                 type: type of loader used for the visit
                 date: timestamp of such visit
                 status: Visit's new status
                 metadata: Data associated to the visit
                 snapshot (sha1_git): identifier of the snapshot to add to
                     the visit
         """
         visits = [OriginVisit.from_dict(d) for d in visits]
 
         if self.journal_writer:
             for visit in visits:
                 (_, visit.origin) = self._origins[visit.origin.url]
                 self.journal_writer.write_addition('origin_visit', visit)
 
         for visit in visits:
             visit_id = visit.visit
             origin_url = visit.origin.url
 
             self._objects[(origin_url, visit_id)].append(
                 ('origin_visit', None))
 
             while len(self._origin_visits[origin_url]) <= visit_id:
                 self._origin_visits[origin_url].append(None)
 
             self._origin_visits[origin_url][visit_id-1] = visit
 
     def _convert_visit(self, visit):
         if visit is None:
             return
 
         (origin_id, origin) = self._origins[visit.origin.url]
         visit = visit.to_dict()
         if ENABLE_ORIGIN_IDS:
             visit['origin'] = origin_id
         else:
             visit['origin'] = origin.url
 
         return visit
 
     def origin_visit_get(self, origin, last_visit=None, limit=None):
         """Retrieve all the origin's visit's information.
 
         Args:
             origin (int): the origin's identifier
             last_visit (int): visit's id from which listing the next ones,
                 default to None
             limit (int): maximum number of results to return,
                 default to None
 
         Yields:
             List of visits.
 
         """
         origin_url = self._get_origin_url(origin)
         if origin_url in self._origin_visits:
             visits = self._origin_visits[origin_url]
             if last_visit is not None:
                 visits = visits[last_visit:]
             if limit is not None:
                 visits = visits[:limit]
             for visit in visits:
                 if not visit:
                     continue
                 visit_id = visit.visit
 
                 yield self._convert_visit(
                     self._origin_visits[origin_url][visit_id-1])
 
     def origin_visit_find_by_date(self, origin, visit_date):
         """Retrieves the origin visit whose date is closest to the provided
         timestamp.
         In case of a tie, the visit with largest id is selected.
 
         Args:
             origin (str): The occurrence's origin (URL).
             target (datetime): target timestamp
 
         Returns:
             A visit.
 
         """
         origin_url = self._get_origin_url(origin)
         if origin_url in self._origin_visits:
             visits = self._origin_visits[origin_url]
             visit = min(
                 visits,
                 key=lambda v: (abs(v.date - visit_date), -v.visit))
             return self._convert_visit(visit)
 
     def origin_visit_get_by(self, origin, visit):
         """Retrieve origin visit's information.
 
         Args:
             origin (int): the origin's identifier
 
         Returns:
             The information on that particular (origin, visit) or None if
             it does not exist
 
         """
         origin_url = self._get_origin_url(origin)
         if origin_url in self._origin_visits and \
            visit <= len(self._origin_visits[origin_url]):
             return self._convert_visit(
                 self._origin_visits[origin_url][visit-1])
 
     def origin_visit_get_latest(
             self, origin, allowed_statuses=None, require_snapshot=False):
         """Get the latest origin visit for the given origin, optionally
         looking only for those with one of the given allowed_statuses
         or for those with a known snapshot.
 
         Args:
             origin (str): the origin's URL
             allowed_statuses (list of str): list of visit statuses considered
                 to find the latest visit. For instance,
                 ``allowed_statuses=['full']`` will only consider visits that
                 have successfully run to completion.
             require_snapshot (bool): If True, only a visit with a snapshot
                 will be returned.
         Returns:
             dict: a dict with the following keys:
 
                 origin: the URL of the origin
                 visit: origin visit id
                 type: type of loader used for the visit
                 date: timestamp of such visit
                 status: Visit's new status
                 metadata: Data associated to the visit
                 snapshot (Optional[sha1_git]): identifier of the snapshot
                     associated to the visit
         """
         res = self._origins.get(origin)
         if not res:
             return
         (_, origin) = res
         visits = self._origin_visits[origin.url]
         if allowed_statuses is not None:
             visits = [visit for visit in visits
                       if visit.status in allowed_statuses]
         if require_snapshot:
             visits = [visit for visit in visits
                       if visit.snapshot]
 
         visit = max(
             visits, key=lambda v: (v.date, v.visit), default=None)
         return self._convert_visit(visit)
 
     def stat_counters(self):
         """compute statistics about the number of tuples in various tables
 
         Returns:
             dict: a dictionary mapping textual labels (e.g., content) to
             integer values (e.g., the number of tuples in table content)
 
         """
         keys = (
             'content',
             'directory',
             'origin',
             'origin_visit',
             'person',
             'release',
             'revision',
             'skipped_content',
             'snapshot'
             )
         stats = {key: 0 for key in keys}
         stats.update(collections.Counter(
             obj_type
             for (obj_type, obj_id)
             in itertools.chain(*self._objects.values())))
         return stats
 
     def refresh_stat_counters(self):
         """Recomputes the statistics for `stat_counters`."""
         pass
 
     def origin_metadata_add(self, origin_id, ts, provider, tool, metadata,
                             db=None, cur=None):
         """ Add an origin_metadata for the origin at ts with provenance and
         metadata.
 
         Args:
             origin_id (int): the origin's id for which the metadata is added
             ts (datetime): timestamp of the found metadata
             provider: id of the provider of metadata (ex:'hal')
             tool: id of the tool used to extract metadata
             metadata (jsonb): the metadata retrieved at the time and location
         """
         if isinstance(origin_id, str):
             origin = self.origin_get({'url': origin_id})
             if not origin:
                 return
             origin_id = origin['id']
 
         if isinstance(ts, str):
             ts = dateutil.parser.parse(ts)
 
         origin_metadata = {
                 'origin_id': origin_id,
                 'discovery_date': ts,
                 'tool_id': tool,
                 'metadata': metadata,
                 'provider_id': provider,
                 }
         self._origin_metadata[origin_id].append(origin_metadata)
         return None
 
     def origin_metadata_get_by(self, origin_id, provider_type=None, db=None,
                                cur=None):
         """Retrieve list of all origin_metadata entries for the origin_id
 
         Args:
             origin_id (int): the unique origin's identifier
             provider_type (str): (optional) type of provider
 
         Returns:
             list of dicts: the origin_metadata dictionary with the keys:
 
             - origin_id (int): origin's identifier
             - discovery_date (datetime): timestamp of discovery
             - tool_id (int): metadata's extracting tool
             - metadata (jsonb)
             - provider_id (int): metadata's provider
             - provider_name (str)
             - provider_type (str)
             - provider_url (str)
 
         """
         if isinstance(origin_id, str):
             origin = self.origin_get({'url': origin_id})
             if not origin:
                 return
             origin_id = origin['id']
 
         metadata = []
         for item in self._origin_metadata[origin_id]:
             item = copy.deepcopy(item)
             provider = self.metadata_provider_get(item['provider_id'])
             for attr_name in ('name', 'type', 'url'):
                 item['provider_' + attr_name] = \
                     provider['provider_' + attr_name]
             metadata.append(item)
         return metadata
 
     def tool_add(self, tools):
         """Add new tools to the storage.
 
         Args:
             tools (iterable of :class:`dict`): Tool information to add to
               storage. Each tool is a :class:`dict` with the following keys:
 
               - name (:class:`str`): name of the tool
               - version (:class:`str`): version of the tool
               - configuration (:class:`dict`): configuration of the tool,
                 must be json-encodable
 
         Returns:
             :class:`dict`: All the tools inserted in storage
             (including the internal ``id``). The order of the list is not
             guaranteed to match the order of the initial list.
 
         """
         inserted = []
         for tool in tools:
             key = self._tool_key(tool)
             assert 'id' not in tool
             record = copy.deepcopy(tool)
             record['id'] = key  # TODO: remove this
             if key not in self._tools:
                 self._tools[key] = record
             inserted.append(copy.deepcopy(self._tools[key]))
 
         return inserted
 
     def tool_get(self, tool):
         """Retrieve tool information.
 
         Args:
             tool (dict): Tool information we want to retrieve from storage.
               The dicts have the same keys as those used in :func:`tool_add`.
 
         Returns:
             dict: The full tool information if it exists (``id`` included),
             None otherwise.
 
         """
         return self._tools.get(self._tool_key(tool))
 
     def metadata_provider_add(self, provider_name, provider_type, provider_url,
                               metadata):
         """Add a metadata provider.
 
         Args:
             provider_name (str): Its name
             provider_type (str): Its type
             provider_url (str): Its URL
             metadata: JSON-encodable object
 
         Returns:
             an identifier of the provider
         """
         provider = {
                 'provider_name': provider_name,
                 'provider_type': provider_type,
                 'provider_url': provider_url,
                 'metadata': metadata,
                 }
         key = self._metadata_provider_key(provider)
         provider['id'] = key
         self._metadata_providers[key] = provider
         return key
 
     def metadata_provider_get(self, provider_id, db=None, cur=None):
         """Get a metadata provider
 
         Args:
             provider_id: Its identifier, as given by `metadata_provider_add`.
 
         Returns:
             dict: same as `metadata_provider_add`;
                   or None if it does not exist.
         """
         return self._metadata_providers.get(provider_id)
 
     def metadata_provider_get_by(self, provider, db=None, cur=None):
         """Get a metadata provider
 
         Args:
             provider_name: Its name
             provider_url: Its URL
 
         Returns:
             dict: same as `metadata_provider_add`;
                   or None if it does not exist.
         """
         key = self._metadata_provider_key(provider)
         return self._metadata_providers.get(key)
 
     def _get_origin_url(self, origin):
         if isinstance(origin, str):
             return origin
         elif isinstance(origin, int):
             if origin <= len(self._origins_by_id):
                 return self._origins_by_id[origin-1]
             else:
                 return None
         else:
             raise TypeError('origin must be a string or an integer.')
 
     def _person_add(self, person):
         """Add a person in storage.
 
         Note: Private method, do not use outside of this class.
 
         Args:
             person: dictionary with keys fullname, name and email.
 
         """
         key = ('person', person.fullname)
         if key not in self._objects:
             person_id = len(self._persons) + 1
             self._persons.append(person)
             self._objects[key].append(('person', person_id))
         else:
             person_id = self._objects[key][0][1]
             person = self._persons[person_id-1]
         return person
 
     @staticmethod
     def _content_key(content):
         """A stable key for a content"""
         return tuple(getattr(content, key)
                      for key in sorted(DEFAULT_ALGORITHMS))
 
     @staticmethod
     def _content_key_algorithm(content):
         """ A stable key and the algorithm for a content"""
         if isinstance(content, Content):
             content = content.to_dict()
         return tuple((content.get(key), key)
                      for key in sorted(DEFAULT_ALGORITHMS))
 
     @staticmethod
     def _tool_key(tool):
         return '%r %r %r' % (tool['name'], tool['version'],
                              tuple(sorted(tool['configuration'].items())))
 
     @staticmethod
     def _metadata_provider_key(provider):
         return '%r %r' % (provider['provider_name'], provider['provider_url'])
diff --git a/swh/storage/tests/algos/test_snapshot.py b/swh/storage/tests/algos/test_snapshot.py
index 2741c58d..d1b0fd63 100644
--- a/swh/storage/tests/algos/test_snapshot.py
+++ b/swh/storage/tests/algos/test_snapshot.py
@@ -1,53 +1,43 @@
 # Copyright (C) 2018  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
-import unittest
-
-import pytest
-
 from hypothesis import given
-from hypothesis.strategies import datetimes
 
 from swh.model.identifiers import snapshot_identifier, identifier_to_bytes
 from swh.model.hypothesis_strategies import \
-    origins, snapshots, branch_names, branch_targets
-from swh.storage.tests.storage_testing import StorageTestFixture
+    snapshots, branch_names, branch_targets
 
 from swh.storage.algos.snapshot import snapshot_get_all_branches
+from swh.storage.tests.test_in_memory import swh_storage  # noqa
+
+
+@given(snapshot=snapshots(min_size=0, max_size=10, only_objects=False))
+def test_snapshot_small(swh_storage, snapshot):  # noqa
+    snapshot = snapshot.to_dict()
+    swh_storage.snapshot_add([snapshot])
+
+    returned_snapshot = snapshot_get_all_branches(
+        swh_storage, snapshot['id'])
+    assert snapshot == returned_snapshot
+
 
+@given(branch_name=branch_names(),
+       branch_target=branch_targets(only_objects=True))
+def test_snapshot_large(swh_storage, branch_name, branch_target):  # noqa
+    branch_target = branch_target.to_dict()
 
-@pytest.mark.db
-@pytest.mark.property_based
-class TestSnapshotAllBranches(StorageTestFixture, unittest.TestCase):
-    @given(origins().map(lambda x: x.to_dict()),
-           datetimes(),
-           snapshots(min_size=0, max_size=10, only_objects=False))
-    def test_snapshot_small(self, origin, ts, snapshot):
-        snapshot = snapshot.to_dict()
-        self.storage.snapshot_add([snapshot])
-
-        returned_snapshot = snapshot_get_all_branches(self.storage,
-                                                      snapshot['id'])
-        self.assertEqual(snapshot, returned_snapshot)
-
-    @given(origins().map(lambda x: x.to_dict()),
-           datetimes(),
-           branch_names(), branch_targets(only_objects=True))
-    def test_snapshot_large(self, origin, ts, branch_name, branch_target):
-        branch_target = branch_target.to_dict()
-
-        snapshot = {
-            'branches': {
-                b'%s%05d' % (branch_name, i): branch_target
-                for i in range(10000)
-            }
+    snapshot = {
+        'branches': {
+            b'%s%05d' % (branch_name, i): branch_target
+            for i in range(10000)
         }
-        snapshot['id'] = identifier_to_bytes(snapshot_identifier(snapshot))
+    }
+    snapshot['id'] = identifier_to_bytes(snapshot_identifier(snapshot))
 
-        self.storage.snapshot_add([snapshot])
+    swh_storage.snapshot_add([snapshot])
 
-        returned_snapshot = snapshot_get_all_branches(self.storage,
-                                                      snapshot['id'])
-        self.assertEqual(snapshot, returned_snapshot)
+    returned_snapshot = snapshot_get_all_branches(
+        swh_storage, snapshot['id'])
+    assert snapshot == returned_snapshot
diff --git a/swh/storage/tests/conftest.py b/swh/storage/tests/conftest.py
new file mode 100644
index 00000000..dff3a79f
--- /dev/null
+++ b/swh/storage/tests/conftest.py
@@ -0,0 +1,191 @@
+from os import path, environ
+import glob
+import pytest
+
+from pytest_postgresql import factories
+from pytest_postgresql.janitor import DatabaseJanitor, psycopg2
+from hypothesis import strategies
+from swh.model.hypothesis_strategies import origins, contents
+
+from swh.core.utils import numfile_sortkey as sortkey
+import swh.storage
+
+SQL_DIR = path.join(path.dirname(swh.storage.__file__), 'sql')
+
+environ['LC_ALL'] = 'C.UTF-8'
+
+DUMP_FILES = path.join(SQL_DIR, '*.sql')
+
+
+@pytest.fixture
+def swh_storage(postgresql_proc, swh_storage_postgresql):
+    storage_config = {
+        'cls': 'local',
+        'args': {
+            'db': 'postgresql://{user}@{host}:{port}/{dbname}'.format(
+                host=postgresql_proc.host,
+                port=postgresql_proc.port,
+                user='postgres',
+                dbname='tests'),
+            'objstorage': {
+                'cls': 'memory',
+                'args': {}
+            },
+            'journal_writer': {
+                'cls': 'memory',
+            },
+        },
+    }
+    storage = swh.storage.get_storage(**storage_config)
+    return storage
+
+
+def gen_origins(n=20):
+    return strategies.lists(
+        origins().map(lambda x: x.to_dict()),
+        unique_by=lambda x: x['url'],
+        min_size=n, max_size=n).example()
+
+
+def gen_contents(n=20):
+    return strategies.lists(
+        contents().map(lambda x: x.to_dict()),
+        unique_by=lambda x: (x['sha1'], x['sha1_git']),
+        min_size=n, max_size=n).example()
+
+
+@pytest.fixture
+def swh_contents(swh_storage):
+    contents = gen_contents()
+    swh_storage.content_add(contents)
+    return contents
+
+
+@pytest.fixture
+def swh_origins(swh_storage):
+    origins = gen_origins()
+    swh_storage.origin_add(origins)
+    return origins
+
+
+# the postgres_fact factory fixture below is mostly a copy of the code
+# from pytest-postgresql. We need a custom version here to be able to
+# specify our version of the DBJanitor we use.
+def postgresql_fact(process_fixture_name, db_name=None):
+    @pytest.fixture
+    def postgresql_factory(request):
+        """
+        Fixture factory for PostgreSQL.
+
+        :param FixtureRequest request: fixture request object
+        :rtype: psycopg2.connection
+        :returns: postgresql client
+        """
+        config = factories.get_config(request)
+        if not psycopg2:
+            raise ImportError(
+                'No module named psycopg2. Please install it.'
+            )
+        proc_fixture = request.getfixturevalue(process_fixture_name)
+
+        # _, config = try_import('psycopg2', request)
+        pg_host = proc_fixture.host
+        pg_port = proc_fixture.port
+        pg_user = proc_fixture.user
+        pg_options = proc_fixture.options
+        pg_db = db_name or config['dbname']
+
+        with SwhDatabaseJanitor(
+                pg_user, pg_host, pg_port, pg_db, proc_fixture.version
+        ):
+            connection = psycopg2.connect(
+                dbname=pg_db,
+                user=pg_user,
+                host=pg_host,
+                port=pg_port,
+                options=pg_options
+            )
+            yield connection
+            connection.close()
+
+    return postgresql_factory
+
+
+swh_storage_postgresql = postgresql_fact('postgresql_proc')
+
+
+# This version of the DatabaseJanitor implement a different setup/teardown
+# behavior than than the stock one: instead of droping, creating and
+# initializing the database for each test, it create and initialize the db only
+# once, then it truncate the tables. This is needed to have acceptable test
+# performances.
+class SwhDatabaseJanitor(DatabaseJanitor):
+    def db_setup(self):
+        with psycopg2.connect(
+            dbname=self.db_name,
+            user=self.user,
+            host=self.host,
+            port=self.port,
+        ) as cnx:
+            with cnx.cursor() as cur:
+                all_dump_files = sorted(
+                    glob.glob(DUMP_FILES), key=sortkey)
+                for fname in all_dump_files:
+                    with open(fname) as fobj:
+                        sql = fobj.read().replace('concurrently', '')
+                        cur.execute(sql)
+            cnx.commit()
+
+    def db_reset(self):
+        with psycopg2.connect(
+            dbname=self.db_name,
+            user=self.user,
+            host=self.host,
+            port=self.port,
+        ) as cnx:
+            with cnx.cursor() as cur:
+                cur.execute(
+                    "SELECT table_name FROM information_schema.tables "
+                    "WHERE table_schema = %s", ('public',))
+                tables = set(table for (table,) in cur.fetchall())
+                for table in tables:
+                    cur.execute('truncate table %s cascade' % table)
+
+                cur.execute(
+                    "SELECT sequence_name FROM information_schema.sequences "
+                    "WHERE sequence_schema = %s", ('public',))
+                seqs = set(seq for (seq,) in cur.fetchall())
+                for seq in seqs:
+                    cur.execute('ALTER SEQUENCE %s RESTART;' % seq)
+            cnx.commit()
+
+    def init(self):
+        with self.cursor() as cur:
+            cur.execute(
+                "SELECT COUNT(1) FROM pg_database WHERE datname=%s;",
+                (self.db_name,))
+            db_exists = cur.fetchone()[0] == 1
+            if db_exists:
+                cur.execute(
+                    'UPDATE pg_database SET datallowconn=true '
+                    'WHERE datname = %s;',
+                    (self.db_name,))
+
+        if db_exists:
+            self.db_reset()
+        else:
+            with self.cursor() as cur:
+                cur.execute('CREATE DATABASE "{}";'.format(self.db_name))
+            self.db_setup()
+
+    def drop(self):
+        pid_column = 'pid'
+        with self.cursor() as cur:
+            cur.execute(
+                'UPDATE pg_database SET datallowconn=false '
+                'WHERE datname = %s;', (self.db_name,))
+            cur.execute(
+                'SELECT pg_terminate_backend(pg_stat_activity.{})'
+                'FROM pg_stat_activity '
+                'WHERE pg_stat_activity.datname = %s;'.format(pid_column),
+                (self.db_name,))
diff --git a/swh/storage/tests/storage_data.py b/swh/storage/tests/storage_data.py
new file mode 100644
index 00000000..56836330
--- /dev/null
+++ b/swh/storage/tests/storage_data.py
@@ -0,0 +1,532 @@
+# Copyright (C) 2015-2019  The Software Heritage developers
+# See the AUTHORS file at the top-level directory of this distribution
+# License: GNU General Public License version 3, or any later version
+# See top-level LICENSE file for more information
+
+import datetime
+from swh.model.hashutil import hash_to_bytes
+from swh.model import from_disk
+
+
+class StorageData:
+    def __getattr__(self, key):
+        v = globals()[key]
+        if hasattr(v, 'copy'):
+            return v.copy()
+        return v
+
+
+data = StorageData()
+
+
+cont = {
+    'data': b'42\n',
+    'length': 3,
+    'sha1': hash_to_bytes(
+        '34973274ccef6ab4dfaaf86599792fa9c3fe4689'),
+    'sha1_git': hash_to_bytes(
+        'd81cc0710eb6cf9efd5b920a8453e1e07157b6cd'),
+    'sha256': hash_to_bytes(
+        '673650f936cb3b0a2f93ce09d81be10748b1b203c19e8176b4eefc1964a0cf3a'),
+    'blake2s256': hash_to_bytes(
+        'd5fe1939576527e42cfd76a9455a2432fe7f56669564577dd93c4280e76d661d'),
+    'status': 'visible',
+}
+
+cont2 = {
+    'data': b'4242\n',
+    'length': 5,
+    'sha1': hash_to_bytes(
+        '61c2b3a30496d329e21af70dd2d7e097046d07b7'),
+    'sha1_git': hash_to_bytes(
+        '36fade77193cb6d2bd826161a0979d64c28ab4fa'),
+    'sha256': hash_to_bytes(
+        '859f0b154fdb2d630f45e1ecae4a862915435e663248bb8461d914696fc047cd'),
+    'blake2s256': hash_to_bytes(
+        '849c20fad132b7c2d62c15de310adfe87be94a379941bed295e8141c6219810d'),
+    'status': 'visible',
+}
+
+cont3 = {
+    'data': b'424242\n',
+    'length': 7,
+    'sha1': hash_to_bytes(
+        '3e21cc4942a4234c9e5edd8a9cacd1670fe59f13'),
+    'sha1_git': hash_to_bytes(
+        'c932c7649c6dfa4b82327d121215116909eb3bea'),
+    'sha256': hash_to_bytes(
+        '92fb72daf8c6818288a35137b72155f507e5de8d892712ab96277aaed8cf8a36'),
+    'blake2s256': hash_to_bytes(
+        '76d0346f44e5a27f6bafdd9c2befd304aff83780f93121d801ab6a1d4769db11'),
+    'status': 'visible',
+}
+
+contents = (cont, cont2, cont3)
+
+
+missing_cont = {
+    'data': b'missing\n',
+    'length': 8,
+    'sha1': hash_to_bytes(
+        'f9c24e2abb82063a3ba2c44efd2d3c797f28ac90'),
+    'sha1_git': hash_to_bytes(
+        '33e45d56f88993aae6a0198013efa80716fd8919'),
+    'sha256': hash_to_bytes(
+        '6bbd052ab054ef222c1c87be60cd191addedd24cc882d1f5f7f7be61dc61bb3a'),
+    'blake2s256': hash_to_bytes(
+        '306856b8fd879edb7b6f1aeaaf8db9bbecc993cd7f776c333ac3a782fa5c6eba'),
+    'status': 'absent',
+}
+
+skipped_cont = {
+    'length': 1024 * 1024 * 200,
+    'sha1_git': hash_to_bytes(
+        '33e45d56f88993aae6a0198013efa80716fd8920'),
+    'sha1': hash_to_bytes(
+        '43e45d56f88993aae6a0198013efa80716fd8920'),
+    'sha256': hash_to_bytes(
+        '7bbd052ab054ef222c1c87be60cd191addedd24cc882d1f5f7f7be61dc61bb3a'),
+    'blake2s256': hash_to_bytes(
+        'ade18b1adecb33f891ca36664da676e12c772cc193778aac9a137b8dc5834b9b'),
+    'reason': 'Content too long',
+    'status': 'absent',
+    'origin': 'file:///dev/zero',
+}
+
+skipped_cont2 = {
+    'length': 1024 * 1024 * 300,
+    'sha1_git': hash_to_bytes(
+        '44e45d56f88993aae6a0198013efa80716fd8921'),
+    'sha1': hash_to_bytes(
+        '54e45d56f88993aae6a0198013efa80716fd8920'),
+    'sha256': hash_to_bytes(
+        '8cbd052ab054ef222c1c87be60cd191addedd24cc882d1f5f7f7be61dc61bb3a'),
+    'blake2s256': hash_to_bytes(
+        '9ce18b1adecb33f891ca36664da676e12c772cc193778aac9a137b8dc5834b9b'),
+    'reason': 'Content too long',
+    'status': 'absent',
+}
+
+dir = {
+    'id': hash_to_bytes(
+        '340133423253310030f531e632a733ff37c3a930'),
+    'entries': [
+        {
+            'name': b'foo',
+            'type': 'file',
+            'target': hash_to_bytes(  # cont
+                'd81cc0710eb6cf9efd5b920a8453e1e07157b6cd'),
+            'perms': from_disk.DentryPerms.content,
+        },
+        {
+            'name': b'bar\xc3',
+            'type': 'dir',
+            'target': b'12345678901234567890',
+            'perms': from_disk.DentryPerms.directory,
+        },
+    ],
+}
+
+dir2 = {
+    'id': hash_to_bytes(
+        '340133423253310030f531e632a733ff37c3a935'),
+    'entries': [
+        {
+            'name': b'oof',
+            'type': 'file',
+            'target': hash_to_bytes(  # cont2
+                '36fade77193cb6d2bd826161a0979d64c28ab4fa'),
+            'perms': from_disk.DentryPerms.content,
+        }
+    ],
+}
+
+dir3 = {
+    'id': hash_to_bytes('33e45d56f88993aae6a0198013efa80716fd8921'),
+    'entries': [
+        {
+            'name': b'foo',
+            'type': 'file',
+            'target': hash_to_bytes(  # cont
+                'd81cc0710eb6cf9efd5b920a8453e1e07157b6cd'),
+            'perms': from_disk.DentryPerms.content,
+        },
+        {
+            'name': b'subdir',
+            'type': 'dir',
+            'target': hash_to_bytes(  # dir
+                '340133423253310030f531e632a733ff37c3a930'),
+            'perms': from_disk.DentryPerms.directory,
+        },
+        {
+            'name': b'hello',
+            'type': 'file',
+            'target': b'12345678901234567890',
+            'perms': from_disk.DentryPerms.content,
+        },
+    ],
+}
+
+dir4 = {
+    'id': hash_to_bytes('33e45d56f88993aae6a0198013efa80716fd8922'),
+    'entries': [
+        {
+            'name': b'subdir1',
+            'type': 'dir',
+            'target': hash_to_bytes(
+                '33e45d56f88993aae6a0198013efa80716fd8921'),  # dir3
+            'perms': from_disk.DentryPerms.directory,
+        },
+    ]
+}
+
+dierctories = (dir, dir2, dir3, dir4)
+
+
+minus_offset = datetime.timezone(datetime.timedelta(minutes=-120))
+plus_offset = datetime.timezone(datetime.timedelta(minutes=120))
+
+revision = {
+    'id': b'56789012345678901234',
+    'message': b'hello',
+    'author': {
+        'name': b'Nicolas Dandrimont',
+        'email': b'nicolas@example.com',
+        'fullname': b'Nicolas Dandrimont <nicolas@example.com> ',
+    },
+    'date': {
+        'timestamp': 1234567890,
+        'offset': 120,
+        'negative_utc': None,
+    },
+    'committer': {
+        'name': b'St\xc3fano Zacchiroli',
+        'email': b'stefano@example.com',
+        'fullname': b'St\xc3fano Zacchiroli <stefano@example.com>'
+    },
+    'committer_date': {
+        'timestamp': 1123456789,
+        'offset': 0,
+        'negative_utc': True,
+    },
+    'parents': [b'01234567890123456789', b'23434512345123456789'],
+    'type': 'git',
+    'directory': hash_to_bytes(  # dir
+        '340133423253310030f531e632a733ff37c3a930'),
+    'metadata': {
+        'checksums': {
+            'sha1': 'tarball-sha1',
+            'sha256': 'tarball-sha256',
+        },
+        'signed-off-by': 'some-dude',
+        'extra_headers': [
+            ['gpgsig', b'test123'],
+            ['mergetags', [b'foo\\bar', b'\x22\xaf\x89\x80\x01\x00']],
+        ],
+    },
+    'synthetic': True
+}
+
+revision2 = {
+    'id': b'87659012345678904321',
+    'message': b'hello again',
+    'author': {
+        'name': b'Roberto Dicosmo',
+        'email': b'roberto@example.com',
+        'fullname': b'Roberto Dicosmo <roberto@example.com>',
+    },
+    'date': {
+        'timestamp': {
+            'seconds': 1234567843,
+            'microseconds': 220000,
+        },
+        'offset': -720,
+        'negative_utc': None,
+    },
+    'committer': {
+        'name': b'tony',
+        'email': b'ar@dumont.fr',
+        'fullname': b'tony <ar@dumont.fr>',
+    },
+    'committer_date': {
+        'timestamp': 1123456789,
+        'offset': 0,
+        'negative_utc': False,
+    },
+    'parents': [b'01234567890123456789'],
+    'type': 'git',
+    'directory': hash_to_bytes(  # dir2
+        '340133423253310030f531e632a733ff37c3a935'),
+    'metadata': None,
+    'synthetic': False
+}
+
+revision3 = {
+    'id': hash_to_bytes('7026b7c1a2af56521e951c01ed20f255fa054238'),
+    'message': b'a simple revision with no parents this time',
+    'author': {
+        'name': b'Roberto Dicosmo',
+        'email': b'roberto@example.com',
+        'fullname': b'Roberto Dicosmo <roberto@example.com>',
+    },
+    'date': {
+        'timestamp': {
+            'seconds': 1234567843,
+            'microseconds': 220000,
+        },
+        'offset': -720,
+        'negative_utc': None,
+    },
+    'committer': {
+        'name': b'tony',
+        'email': b'ar@dumont.fr',
+        'fullname': b'tony <ar@dumont.fr>',
+    },
+    'committer_date': {
+        'timestamp': 1127351742,
+        'offset': 0,
+        'negative_utc': False,
+    },
+    'parents': [],
+    'type': 'git',
+    'directory': hash_to_bytes(  # dir2
+        '340133423253310030f531e632a733ff37c3a935'),
+    'metadata': None,
+    'synthetic': True
+}
+
+revision4 = {
+    'id': hash_to_bytes('368a48fe15b7db2383775f97c6b247011b3f14f4'),
+    'message': b'parent of self.revision2',
+    'author': {
+        'name': b'me',
+        'email': b'me@soft.heri',
+        'fullname': b'me <me@soft.heri>',
+    },
+    'date': {
+        'timestamp': {
+            'seconds': 1244567843,
+            'microseconds': 220000,
+        },
+        'offset': -720,
+        'negative_utc': None,
+    },
+    'committer': {
+        'name': b'committer-dude',
+        'email': b'committer@dude.com',
+        'fullname': b'committer-dude <committer@dude.com>',
+    },
+    'committer_date': {
+        'timestamp': {
+            'seconds': 1244567843,
+            'microseconds': 220000,
+        },
+        'offset': -720,
+        'negative_utc': None,
+    },
+    'parents': [hash_to_bytes(  # revision3
+        '7026b7c1a2af56521e951c01ed20f255fa054238')],
+    'type': 'git',
+    'directory': hash_to_bytes(  # dir
+        '340133423253310030f531e632a733ff37c3a930'),
+    'metadata': None,
+    'synthetic': False
+}
+
+revisions = (revision, revision2, revision3, revision4)
+
+
+origin = {
+    'url': 'file:///dev/null',
+    'type': 'git',
+}
+
+origin2 = {
+    'url': 'file:///dev/zero',
+    'type': 'hg',
+}
+
+origins = (origin, origin2)
+
+
+provider = {
+    'name': 'hal',
+    'type': 'deposit-client',
+    'url': 'http:///hal/inria',
+    'metadata': {
+        'location': 'France'
+    }
+}
+
+metadata_tool = {
+    'name': 'swh-deposit',
+    'version': '0.0.1',
+    'configuration': {
+        'sword_version': '2'
+    }
+}
+
+date_visit1 = datetime.datetime(2015, 1, 1, 23, 0, 0,
+                                tzinfo=datetime.timezone.utc)
+
+date_visit2 = datetime.datetime(2017, 1, 1, 23, 0, 0,
+                                tzinfo=datetime.timezone.utc)
+
+date_visit3 = datetime.datetime(2018, 1, 1, 23, 0, 0,
+                                tzinfo=datetime.timezone.utc)
+
+release = {
+    'id': b'87659012345678901234',
+    'name': b'v0.0.1',
+    'author': {
+        'name': b'olasd',
+        'email': b'nic@olasd.fr',
+        'fullname': b'olasd <nic@olasd.fr>',
+    },
+    'date': {
+        'timestamp': 1234567890,
+        'offset': 42,
+        'negative_utc': None,
+    },
+    'target': b'43210987654321098765',
+    'target_type': 'revision',
+    'message': b'synthetic release',
+    'synthetic': True,
+}
+
+release2 = {
+    'id': b'56789012348765901234',
+    'name': b'v0.0.2',
+    'author': {
+        'name': b'tony',
+        'email': b'ar@dumont.fr',
+        'fullname': b'tony <ar@dumont.fr>',
+    },
+    'date': {
+        'timestamp': 1634366813,
+        'offset': -120,
+        'negative_utc': None,
+    },
+    'target': b'432109\xa9765432\xc309\x00765',
+    'target_type': 'revision',
+    'message': b'v0.0.2\nMisc performance improvements + bug fixes',
+    'synthetic': False
+}
+
+release3 = {
+    'id': b'87659012345678904321',
+    'name': b'v0.0.2',
+    'author': {
+        'name': b'tony',
+        'email': b'tony@ardumont.fr',
+        'fullname': b'tony <tony@ardumont.fr>',
+    },
+    'date': {
+        'timestamp': 1634336813,
+        'offset': 0,
+        'negative_utc': False,
+    },
+    'target': b'87659012345678904321',  # revision2
+    'target_type': 'revision',
+    'message': b'yet another synthetic release',
+    'synthetic': True,
+}
+
+releases = (release, release2, release3)
+
+
+fetch_history_date = datetime.datetime(
+    2015, 1, 2, 21, 0, 0,
+    tzinfo=datetime.timezone.utc)
+
+fetch_history_end = datetime.datetime(
+    2015, 1, 2, 23, 0, 0,
+    tzinfo=datetime.timezone.utc)
+
+fetch_history_data = {
+    'status': True,
+    'result': {'foo': 'bar'},
+    'stdout': 'blabla',
+    'stderr': 'blablabla',
+}
+
+snapshot = {
+    'id': hash_to_bytes('2498dbf535f882bc7f9a18fb16c9ad27fda7bab7'),
+    'branches': {
+        b'master': {
+            'target': b'56789012345678901234',  # revision
+            'target_type': 'revision',
+        },
+    },
+}
+
+empty_snapshot = {
+    'id': hash_to_bytes('1a8893e6a86f444e8be8e7bda6cb34fb1735a00e'),
+    'branches': {},
+}
+
+complete_snapshot = {
+    'id': hash_to_bytes('6e65b86363953b780d92b0a928f3e8fcdd10db36'),
+    'branches': {
+        b'directory': {
+            'target': hash_to_bytes(
+                '1bd0e65f7d2ff14ae994de17a1e7fe65111dcad8'),
+            'target_type': 'directory',
+        },
+        b'directory2': {
+            'target': hash_to_bytes(
+                '1bd0e65f7d2ff14ae994de17a1e7fe65111dcad8'),
+            'target_type': 'directory',
+        },
+        b'content': {
+            'target': hash_to_bytes(
+                'fe95a46679d128ff167b7c55df5d02356c5a1ae1'),
+            'target_type': 'content',
+        },
+        b'alias': {
+            'target': b'revision',
+            'target_type': 'alias',
+        },
+        b'revision': {
+            'target': hash_to_bytes(
+                'aafb16d69fd30ff58afdd69036a26047f3aebdc6'),
+            'target_type': 'revision',
+        },
+        b'release': {
+            'target': hash_to_bytes(
+                '7045404f3d1c54e6473c71bbb716529fbad4be24'),
+            'target_type': 'release',
+        },
+        b'snapshot': {
+            'target': hash_to_bytes(
+                '1a8893e6a86f444e8be8e7bda6cb34fb1735a00e'),
+            'target_type': 'snapshot',
+        },
+        b'dangling': None,
+    }
+}
+
+origin_metadata = {
+        'origin': origin,
+        'discovery_date': datetime.datetime(2015, 1, 1, 23, 0, 0,
+                                            tzinfo=datetime.timezone.utc),
+        'provider': provider,
+        'tool': 'swh-deposit',
+        'metadata': {
+            'name': 'test_origin_metadata',
+            'version': '0.0.1'
+        }
+    }
+origin_metadata2 = {
+        'origin': origin,
+        'discovery_date': datetime.datetime(2017, 1, 1, 23, 0, 0,
+                                            tzinfo=datetime.timezone.utc),
+        'provider': provider,
+        'tool': 'swh-deposit',
+        'metadata': {
+            'name': 'test_origin_metadata',
+            'version': '0.0.1'
+        }
+    }
+
+fetch_history_duration = (fetch_history_end - fetch_history_date)
diff --git a/swh/storage/tests/test_api_client.py b/swh/storage/tests/test_api_client.py
index cc029076..5b2d6648 100644
--- a/swh/storage/tests/test_api_client.py
+++ b/swh/storage/tests/test_api_client.py
@@ -1,152 +1,58 @@
 # Copyright (C) 2015-2018  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
-from contextlib import contextmanager
-import shutil
-import tempfile
-import unittest
-
 import pytest
 
-from swh.core.api.tests.server_testing import ServerTestFixture
-from swh.journal.writer import get_journal_writer
 from swh.storage.api.client import RemoteStorage
 import swh.storage.api.server as server
-from swh.storage.api.server import app
-from swh.storage.in_memory import Storage as InMemoryStorage
 import swh.storage.storage
-from swh.storage.db import Db
-from swh.storage.tests.test_storage import \
-    CommonTestStorage, CommonPropTestStorage, StorageTestDbFixture
-
-
-class RemotePgStorageFixture(StorageTestDbFixture, ServerTestFixture,
-                             unittest.TestCase):
-    def setUp(self):
-        journal_writer = get_journal_writer(cls='memory')
-
-        def mock_get_journal_writer(cls, args=None):
-            assert cls == 'memory'
-            return journal_writer
-
-        self.journal_writer = journal_writer
-        server.storage = None
-        self.get_journal_writer = get_journal_writer
-        swh.storage.storage.get_journal_writer = mock_get_journal_writer
-
-        # ServerTestFixture needs to have self.objroot for
-        # setUp() method, but this field is defined in
-        # AbstractTestStorage's setUp()
-        # To avoid confusion, override the self.objroot to a
-        # one chosen in this class.
-        self.storage_base = tempfile.mkdtemp()
-        self.objroot = self.storage_base
-        self.config = {
-            'storage': {
-                'cls': 'local',
-                'args': {
-                    'db': 'dbname=%s' % self.TEST_DB_NAME,
-                    'objstorage': {
-                        'cls': 'pathslicing',
-                        'args': {
-                            'root': self.storage_base,
-                            'slicing': '0:2',
-                        },
-                    },
-                    'journal_writer': {
-                        'cls': 'memory',
-                    }
-                }
-            }
-        }
-        self.app = app
-        super().setUp()
-        self.storage = RemoteStorage(self.url())
+from swh.storage.tests.test_storage import (  # noqa
+    TestStorage, TestStorageGeneratedData)
 
-    def tearDown(self):
-        super().tearDown()
-        shutil.rmtree(self.storage_base)
-        swh.storage.storage.get_journal_writer = self.get_journal_writer
+# tests are executed using imported classes (TestStorage and
+# TestStorageGeneratedData) using overloaded swh_storage fixture
+# below
 
-    def reset_storage(self):
-        excluded = {'dbversion', 'tool'}
-        self.reset_db_tables(self.TEST_DB_NAME, excluded=excluded)
-        self.journal_writer.objects[:] = []
 
-    @contextmanager
-    def get_db(self):
-        yield Db(self.conn)
-
-
-class RemoteMemStorageFixture(ServerTestFixture, unittest.TestCase):
-    def setUp(self):
-        self.config = {
-            'storage': {
+@pytest.fixture
+def app():
+    storage_config = {
+        'cls': 'memory',
+        'args': {
+            'journal_writer': {
                 'cls': 'memory',
-                'args': {
-                    'journal_writer': {
-                        'cls': 'memory',
-                    }
-                }
-            }
-        }
-        self.__storage = InMemoryStorage(
-            journal_writer={'cls': 'memory'})
-
-        self._get_storage_patcher = unittest.mock.patch(
-            'swh.storage.api.server.get_storage', return_value=self.__storage)
-        self._get_storage_patcher.start()
-        self.app = app
-        super().setUp()
-        self.storage = RemoteStorage(self.url())
-        self.journal_writer = self.__storage.journal_writer
-
-    def tearDown(self):
-        super().tearDown()
-        self._get_storage_patcher.stop()
-
-    def reset_storage(self):
-        self.storage.reset()
-        self.journal_writer.objects[:] = []
-
-
-@pytest.mark.network
-class TestRemoteMemStorage(CommonTestStorage, RemoteMemStorageFixture):
-    @pytest.mark.skip('refresh_stat_counters not available in the remote api.')
-    def test_stat_counters(self):
-        pass
-
-    @pytest.mark.skip('postgresql-specific test')
-    def test_content_add_db(self):
-        pass
-
-    @pytest.mark.skip('postgresql-specific test')
-    def test_skipped_content_add_db(self):
-        pass
-
-    @pytest.mark.skip('postgresql-specific test')
-    def test_content_add_metadata_db(self):
-        pass
-
-    @pytest.mark.skip(
-        'not implemented, see https://forge.softwareheritage.org/T1633')
-    def test_skipped_content_add(self):
-        pass
-
-
-@pytest.mark.db
-@pytest.mark.network
-class TestRemotePgStorage(CommonTestStorage, RemotePgStorageFixture):
-    @pytest.mark.skip('refresh_stat_counters not available in the remote api.')
-    def test_stat_counters(self):
-        pass
-
-
-@pytest.mark.db
-@pytest.mark.property_based
-class PropTestRemotePgStorage(CommonPropTestStorage, RemotePgStorageFixture):
-    @pytest.mark.skip('too slow')
-    def test_add_arbitrary(self):
-        pass
+            },
+        },
+    }
+    server.storage = swh.storage.get_storage(**storage_config)
+    # hack hack hack!
+    # We attach the journal storage to the app here to make it accessible to
+    # the test (as swh_storage.journal_writer); see swh_storage below.
+    server.app.journal_writer = server.storage.journal_writer
+    yield server.app
+    del server.app.journal_writer
+
+
+@pytest.fixture
+def swh_rpc_client_class():
+    return RemoteStorage
+
+
+@pytest.fixture
+def swh_storage(swh_rpc_client, app):
+    # This version of the swh_storage fixture uses the swh_rpc_client fixture
+    # to instantiate a RemoteStorage (see swh_rpc_client_class above) that
+    # proxies, via the swh.core RPC mechanism, the local (in memory) storage
+    # configured in the app fixture above.
+    #
+    # Also note that, for the sake of
+    # making it easier to write tests, the in-memory journal writer of the
+    # in-memory backend storage is attached to the RemoteStorage as its
+    # journal_writer attribute.
+    storage = swh_rpc_client
+    journal_writer = getattr(storage, 'journal_writer', None)
+    storage.journal_writer = app.journal_writer
+    yield storage
+    storage.journal_writer = journal_writer
diff --git a/swh/storage/tests/test_db.py b/swh/storage/tests/test_db.py
index cb0de06f..5b6205a7 100644
--- a/swh/storage/tests/test_db.py
+++ b/swh/storage/tests/test_db.py
@@ -1,50 +1,31 @@
 # Copyright (C) 2015-2017  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
-import os
-import unittest
 
-import pytest
-
-from swh.core.db.tests.db_testing import SingleDbTestFixture
 from swh.model.hashutil import hash_to_bytes
-from swh.storage.db import Db
-from . import SQL_DIR
-
-
-@pytest.mark.db
-class TestDb(SingleDbTestFixture, unittest.TestCase):
-    TEST_DB_NAME = 'softwareheritage-test-storage'
-    TEST_DB_DUMP = os.path.join(SQL_DIR, '*.sql')
-
-    def setUp(self):
-        super().setUp()
-        self.db = Db(self.conn)
 
-    def tearDown(self):
-        self.db.conn.close()
-        super().tearDown()
 
-    def test_add_content(self):
-        cur = self.cursor
+def test_add_content(swh_storage):
+    with swh_storage.db() as db:
+        cur = db.cursor()
         sha1 = hash_to_bytes('34973274ccef6ab4dfaaf86599792fa9c3fe4689')
-        self.db.mktemp('content', cur)
-        self.db.copy_to([{
+        db.mktemp('content', cur)
+        db.copy_to([{
             'sha1': sha1,
             'sha1_git': hash_to_bytes(
                 'd81cc0710eb6cf9efd5b920a8453e1e07157b6cd'),
             'sha256': hash_to_bytes(
                 '673650f936cb3b0a2f93ce09d81be107'
                 '48b1b203c19e8176b4eefc1964a0cf3a'),
             'blake2s256': hash_to_bytes('69217a3079908094e11121d042354a7c'
                                         '1f55b6482ca1a51e1b250dfd1ed0eef9'),
             'length': 3}],
                         'tmp_content',
                         ['sha1', 'sha1_git', 'sha256', 'blake2s256', 'length'],
                         cur)
-        self.db.content_add_from_temp(cur)
-        self.cursor.execute('SELECT sha1 FROM content WHERE sha1 = %s',
-                            (sha1,))
-        self.assertEqual(self.cursor.fetchone()[0], sha1)
+        db.content_add_from_temp(cur)
+        cur.execute('SELECT sha1 FROM content WHERE sha1 = %s',
+                    (sha1,))
+        assert cur.fetchone()[0] == sha1
diff --git a/swh/storage/tests/test_in_memory.py b/swh/storage/tests/test_in_memory.py
index 67cdb845..37f98427 100644
--- a/swh/storage/tests/test_in_memory.py
+++ b/swh/storage/tests/test_in_memory.py
@@ -1,78 +1,33 @@
 # Copyright (C) 2018  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
-import unittest
 
 import pytest
 
-from swh.storage.in_memory import Storage, ENABLE_ORIGIN_IDS
+from swh.storage import get_storage
+from swh.storage.tests.test_storage import (  # noqa
+    TestStorage, TestStorageGeneratedData)
+from swh.storage.in_memory import ENABLE_ORIGIN_IDS
 
-from swh.storage.tests.test_storage import \
-    CommonTestStorage, CommonPropTestStorage
 
+TestStorage._test_origin_ids = ENABLE_ORIGIN_IDS
+TestStorageGeneratedData._test_origin_ids = ENABLE_ORIGIN_IDS
 
-class TestInMemoryStorage(CommonTestStorage, unittest.TestCase):
-    """Test the in-memory storage API
 
-    This class doesn't define any tests as we want identical
-    functionality between local and remote storage. All the tests are
-    therefore defined in CommonTestStorage.
-    """
-    _test_origin_ids = ENABLE_ORIGIN_IDS
+# tests are executed using imported classes (TestStorage and
+# TestStorageGeneratedData) using overloaded swh_storage fixture
+# below
 
-    def setUp(self):
-        super().setUp()
-        self.reset_storage()
-
-    @pytest.mark.skip('postgresql-specific test')
-    def test_content_add_db(self):
-        pass
-
-    @pytest.mark.skip('postgresql-specific test')
-    def test_skipped_content_add_db(self):
-        pass
-
-    @pytest.mark.skip('postgresql-specific test')
-    def test_content_add_metadata_db(self):
-        pass
-
-    if not _test_origin_ids:
-        @pytest.mark.skip('requires origin ids')
-        def test_origin_metadata_add(self):
-            pass
-
-        @pytest.mark.skip('requires origin ids')
-        def test_origin_metadata_get(self):
-            pass
-
-        @pytest.mark.skip('requires origin ids')
-        def test_origin_metadata_get_by_provider_type(self):
-            pass
-
-    def reset_storage(self):
-        self.storage = Storage(journal_writer={'cls': 'memory'})
-        self.journal_writer = self.storage.journal_writer
-
-
-@pytest.mark.property_based
-class PropTestInMemoryStorage(CommonPropTestStorage, unittest.TestCase):
-    """Test the in-memory storage API
-
-    This class doesn't define any tests as we want identical
-    functionality between local and remote storage. All the tests are
-    therefore defined in CommonPropTestStorage.
-    """
-    _test_origin_ids = ENABLE_ORIGIN_IDS
-
-    def setUp(self):
-        super().setUp()
-        self.storage = Storage()
-
-    def reset_storage(self):
-        self.storage = Storage()
-
-    if not _test_origin_ids:
-        @pytest.mark.skip('requires origin ids')
-        def test_origin_get_range(self, new_origins):
-            pass
+@pytest.fixture
+def swh_storage():
+    storage_config = {
+        'cls': 'memory',
+        'args': {
+            'journal_writer': {
+                'cls': 'memory',
+            },
+        },
+    }
+    storage = get_storage(**storage_config)
+    return storage
diff --git a/swh/storage/tests/test_storage.py b/swh/storage/tests/test_storage.py
index c1243d8d..b059f08e 100644
--- a/swh/storage/tests/test_storage.py
+++ b/swh/storage/tests/test_storage.py
@@ -1,4153 +1,3499 @@
 # Copyright (C) 2015-2019  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import copy
 from contextlib import contextmanager
 import datetime
 import itertools
 import queue
-import random
 import threading
-import unittest
 from collections import defaultdict
 from unittest.mock import Mock, patch
 
 import psycopg2
 import pytest
 
 from hypothesis import given, strategies, settings, HealthCheck
 
 from typing import ClassVar, Optional
 
 from swh.model import from_disk, identifiers
 from swh.model.hashutil import hash_to_bytes
-from swh.model.hypothesis_strategies import origins, objects
-from swh.storage.tests.storage_testing import StorageTestFixture
+from swh.model.hypothesis_strategies import objects
 from swh.storage import HashCollision
 
-from .generate_data_test import gen_contents
+from .storage_data import data
 
 
-@pytest.mark.db
-class StorageTestDbFixture(StorageTestFixture):
-    def setUp(self):
-        super().setUp()
-        self.maxDiff = None
-
-    def tearDown(self):
-        self.reset_storage()
-        if hasattr(self.storage, '_pool') and self.storage._pool:
-            self.storage._pool.closeall()
-        super().tearDown()
-
-    def get_db(self):
-        return self.storage.db()
-
-    @contextmanager
-    def db_transaction(self):
-        with self.get_db() as db:
-            with db.transaction() as cur:
-                yield db, cur
-
-
-class TestStorageData:
-    def setUp(self, *args, **kwargs):
-        super().setUp(*args, **kwargs)
-
-        self.cont = {
-            'data': b'42\n',
-            'length': 3,
-            'sha1': hash_to_bytes(
-                '34973274ccef6ab4dfaaf86599792fa9c3fe4689'),
-            'sha1_git': hash_to_bytes(
-                'd81cc0710eb6cf9efd5b920a8453e1e07157b6cd'),
-            'sha256': hash_to_bytes(
-                '673650f936cb3b0a2f93ce09d81be107'
-                '48b1b203c19e8176b4eefc1964a0cf3a'),
-            'blake2s256': hash_to_bytes('d5fe1939576527e42cfd76a9455a2'
-                                        '432fe7f56669564577dd93c4280e76d661d'),
-            'status': 'visible',
-        }
-
-        self.cont2 = {
-            'data': b'4242\n',
-            'length': 5,
-            'sha1': hash_to_bytes(
-                '61c2b3a30496d329e21af70dd2d7e097046d07b7'),
-            'sha1_git': hash_to_bytes(
-                '36fade77193cb6d2bd826161a0979d64c28ab4fa'),
-            'sha256': hash_to_bytes(
-                '859f0b154fdb2d630f45e1ecae4a8629'
-                '15435e663248bb8461d914696fc047cd'),
-            'blake2s256': hash_to_bytes('849c20fad132b7c2d62c15de310adfe87be'
-                                        '94a379941bed295e8141c6219810d'),
-            'status': 'visible',
-        }
+@contextmanager
+def db_transaction(storage):
+    with storage.db() as db:
+        with db.transaction() as cur:
+            yield db, cur
 
-        self.cont3 = {
-            'data': b'424242\n',
-            'length': 7,
-            'sha1': hash_to_bytes(
-                '3e21cc4942a4234c9e5edd8a9cacd1670fe59f13'),
-            'sha1_git': hash_to_bytes(
-                'c932c7649c6dfa4b82327d121215116909eb3bea'),
-            'sha256': hash_to_bytes(
-                '92fb72daf8c6818288a35137b72155f5'
-                '07e5de8d892712ab96277aaed8cf8a36'),
-            'blake2s256': hash_to_bytes('76d0346f44e5a27f6bafdd9c2befd304af'
-                                        'f83780f93121d801ab6a1d4769db11'),
-            'status': 'visible',
-        }
-
-        self.missing_cont = {
-            'data': b'missing\n',
-            'length': 8,
-            'sha1': hash_to_bytes(
-                'f9c24e2abb82063a3ba2c44efd2d3c797f28ac90'),
-            'sha1_git': hash_to_bytes(
-                '33e45d56f88993aae6a0198013efa80716fd8919'),
-            'sha256': hash_to_bytes(
-                '6bbd052ab054ef222c1c87be60cd191a'
-                'ddedd24cc882d1f5f7f7be61dc61bb3a'),
-            'blake2s256': hash_to_bytes('306856b8fd879edb7b6f1aeaaf8db9bbecc9'
-                                        '93cd7f776c333ac3a782fa5c6eba'),
-            'status': 'absent',
-        }
 
-        self.skipped_cont = {
-            'length': 1024 * 1024 * 200,
-            'sha1_git': hash_to_bytes(
-                '33e45d56f88993aae6a0198013efa80716fd8920'),
-            'sha1': hash_to_bytes(
-                '43e45d56f88993aae6a0198013efa80716fd8920'),
-            'sha256': hash_to_bytes(
-                '7bbd052ab054ef222c1c87be60cd191a'
-                'ddedd24cc882d1f5f7f7be61dc61bb3a'),
-            'blake2s256': hash_to_bytes(
-                'ade18b1adecb33f891ca36664da676e1'
-                '2c772cc193778aac9a137b8dc5834b9b'),
-            'reason': 'Content too long',
-            'status': 'absent',
-            'origin': 'file:///dev/zero',
-        }
+def normalize_entity(entity):
+    entity = copy.deepcopy(entity)
+    for key in ('date', 'committer_date'):
+        if key in entity:
+            entity[key] = identifiers.normalize_timestamp(entity[key])
+    return entity
 
-        self.skipped_cont2 = {
-            'length': 1024 * 1024 * 300,
-            'sha1_git': hash_to_bytes(
-                '44e45d56f88993aae6a0198013efa80716fd8921'),
-            'sha1': hash_to_bytes(
-                '54e45d56f88993aae6a0198013efa80716fd8920'),
-            'sha256': hash_to_bytes(
-                '8cbd052ab054ef222c1c87be60cd191a'
-                'ddedd24cc882d1f5f7f7be61dc61bb3a'),
-            'blake2s256': hash_to_bytes(
-                '9ce18b1adecb33f891ca36664da676e1'
-                '2c772cc193778aac9a137b8dc5834b9b'),
-            'reason': 'Content too long',
-            'status': 'absent',
-        }
 
-        self.dir = {
-            'id': b'4\x013\x422\x531\x000\xf51\xe62\xa73\xff7\xc3\xa90',
-            'entries': [
-                {
-                    'name': b'foo',
-                    'type': 'file',
-                    'target': self.cont['sha1_git'],
-                    'perms': from_disk.DentryPerms.content,
-                },
-                {
-                    'name': b'bar\xc3',
-                    'type': 'dir',
-                    'target': b'12345678901234567890',
-                    'perms': from_disk.DentryPerms.directory,
-                },
-            ],
+def transform_entries(dir_, *, prefix=b''):
+    for ent in dir_['entries']:
+        yield {
+            'dir_id': dir_['id'],
+            'type': ent['type'],
+            'target': ent['target'],
+            'name': prefix + ent['name'],
+            'perms': ent['perms'],
+            'status': None,
+            'sha1': None,
+            'sha1_git': None,
+            'sha256': None,
+            'length': None,
         }
 
-        self.dir2 = {
-            'id': b'4\x013\x422\x531\x000\xf51\xe62\xa73\xff7\xc3\xa95',
-            'entries': [
-                {
-                    'name': b'oof',
-                    'type': 'file',
-                    'target': self.cont2['sha1_git'],
-                    'perms': from_disk.DentryPerms.content,
-                }
-            ],
-        }
 
-        self.dir3 = {
-            'id': hash_to_bytes('33e45d56f88993aae6a0198013efa80716fd8921'),
-            'entries': [
-                {
-                    'name': b'foo',
-                    'type': 'file',
-                    'target': self.cont['sha1_git'],
-                    'perms': from_disk.DentryPerms.content,
-                },
-                {
-                    'name': b'subdir',
-                    'type': 'dir',
-                    'target': self.dir['id'],
-                    'perms': from_disk.DentryPerms.directory,
-                },
-                {
-                    'name': b'hello',
-                    'type': 'file',
-                    'target': b'12345678901234567890',
-                    'perms': from_disk.DentryPerms.content,
-                },
+def cmpdir(directory):
+    return (directory['type'], directory['dir_id'])
 
-            ],
-        }
 
-        self.dir4 = {
-            'id': hash_to_bytes('33e45d56f88993aae6a0198013efa80716fd8922'),
-            'entries': [
-                {
-                    'name': b'subdir1',
-                    'type': 'dir',
-                    'target': self.dir3['id'],
-                    'perms': from_disk.DentryPerms.directory,
-                },
-            ]
-        }
+def short_revision(revision):
+    return [revision['id'], revision['parents']]
 
-        self.minus_offset = datetime.timezone(datetime.timedelta(minutes=-120))
-        self.plus_offset = datetime.timezone(datetime.timedelta(minutes=120))
 
-        self.revision = {
-            'id': b'56789012345678901234',
-            'message': b'hello',
-            'author': {
-                'name': b'Nicolas Dandrimont',
-                'email': b'nicolas@example.com',
-                'fullname': b'Nicolas Dandrimont <nicolas@example.com> ',
-            },
-            'date': {
-                'timestamp': 1234567890,
-                'offset': 120,
-                'negative_utc': None,
-            },
-            'committer': {
-                'name': b'St\xc3fano Zacchiroli',
-                'email': b'stefano@example.com',
-                'fullname': b'St\xc3fano Zacchiroli <stefano@example.com>'
-            },
-            'committer_date': {
-                'timestamp': 1123456789,
-                'offset': 0,
-                'negative_utc': True,
-            },
-            'parents': [b'01234567890123456789', b'23434512345123456789'],
-            'type': 'git',
-            'directory': self.dir['id'],
-            'metadata': {
-                'checksums': {
-                    'sha1': 'tarball-sha1',
-                    'sha256': 'tarball-sha256',
-                },
-                'signed-off-by': 'some-dude',
-                'extra_headers': [
-                    ['gpgsig', b'test123'],
-                    ['mergetags', [b'foo\\bar', b'\x22\xaf\x89\x80\x01\x00']],
-                ],
-            },
-            'synthetic': True
-        }
-
-        self.revision2 = {
-            'id': b'87659012345678904321',
-            'message': b'hello again',
-            'author': {
-                'name': b'Roberto Dicosmo',
-                'email': b'roberto@example.com',
-                'fullname': b'Roberto Dicosmo <roberto@example.com>',
-            },
-            'date': {
-                'timestamp': {
-                    'seconds': 1234567843,
-                    'microseconds': 220000,
-                },
-                'offset': -720,
-                'negative_utc': None,
-            },
-            'committer': {
-                'name': b'tony',
-                'email': b'ar@dumont.fr',
-                'fullname': b'tony <ar@dumont.fr>',
-            },
-            'committer_date': {
-                'timestamp': 1123456789,
-                'offset': 0,
-                'negative_utc': False,
-            },
-            'parents': [b'01234567890123456789'],
-            'type': 'git',
-            'directory': self.dir2['id'],
-            'metadata': None,
-            'synthetic': False
-        }
-
-        self.revision3 = {
-            'id': hash_to_bytes('7026b7c1a2af56521e951c01ed20f255fa054238'),
-            'message': b'a simple revision with no parents this time',
-            'author': {
-                'name': b'Roberto Dicosmo',
-                'email': b'roberto@example.com',
-                'fullname': b'Roberto Dicosmo <roberto@example.com>',
-            },
-            'date': {
-                'timestamp': {
-                    'seconds': 1234567843,
-                    'microseconds': 220000,
-                },
-                'offset': -720,
-                'negative_utc': None,
-            },
-            'committer': {
-                'name': b'tony',
-                'email': b'ar@dumont.fr',
-                'fullname': b'tony <ar@dumont.fr>',
-            },
-            'committer_date': {
-                'timestamp': 1127351742,
-                'offset': 0,
-                'negative_utc': False,
-            },
-            'parents': [],
-            'type': 'git',
-            'directory': self.dir2['id'],
-            'metadata': None,
-            'synthetic': True
-        }
-
-        self.revision4 = {
-            'id': hash_to_bytes('368a48fe15b7db2383775f97c6b247011b3f14f4'),
-            'message': b'parent of self.revision2',
-            'author': {
-                'name': b'me',
-                'email': b'me@soft.heri',
-                'fullname': b'me <me@soft.heri>',
-            },
-            'date': {
-                'timestamp': {
-                    'seconds': 1244567843,
-                    'microseconds': 220000,
-                },
-                'offset': -720,
-                'negative_utc': None,
-            },
-            'committer': {
-                'name': b'committer-dude',
-                'email': b'committer@dude.com',
-                'fullname': b'committer-dude <committer@dude.com>',
-            },
-            'committer_date': {
-                'timestamp': {
-                    'seconds': 1244567843,
-                    'microseconds': 220000,
-                },
-                'offset': -720,
-                'negative_utc': None,
-            },
-            'parents': [self.revision3['id']],
-            'type': 'git',
-            'directory': self.dir['id'],
-            'metadata': None,
-            'synthetic': False
-        }
-
-        self.origin = {
-            'url': 'file:///dev/null',
-            'type': 'git',
-        }
-
-        self.origin2 = {
-            'url': 'file:///dev/zero',
-            'type': 'hg',
-        }
-
-        self.provider = {
-            'name': 'hal',
-            'type': 'deposit-client',
-            'url': 'http:///hal/inria',
-            'metadata': {
-                'location': 'France'
-            }
-        }
-
-        self.metadata_tool = {
-            'name': 'swh-deposit',
-            'version': '0.0.1',
-            'configuration': {
-                'sword_version': '2'
-            }
-        }
-
-        self.origin_metadata = {
-            'origin': self.origin,
-            'discovery_date': datetime.datetime(2015, 1, 1, 23, 0, 0,
-                                                tzinfo=datetime.timezone.utc),
-            'provider': self.provider,
-            'tool': 'swh-deposit',
-            'metadata': {
-                'name': 'test_origin_metadata',
-                'version': '0.0.1'
-             }
-        }
-
-        self.origin_metadata2 = {
-            'origin': self.origin,
-            'discovery_date': datetime.datetime(2017, 1, 1, 23, 0, 0,
-                                                tzinfo=datetime.timezone.utc),
-            'provider': self.provider,
-            'tool': 'swh-deposit',
-            'metadata': {
-                'name': 'test_origin_metadata',
-                'version': '0.0.1'
-             }
-        }
-
-        self.date_visit1 = datetime.datetime(2015, 1, 1, 23, 0, 0,
-                                             tzinfo=datetime.timezone.utc)
-
-        self.date_visit2 = datetime.datetime(2017, 1, 1, 23, 0, 0,
-                                             tzinfo=datetime.timezone.utc)
-
-        self.date_visit3 = datetime.datetime(2018, 1, 1, 23, 0, 0,
-                                             tzinfo=datetime.timezone.utc)
-
-        self.release = {
-            'id': b'87659012345678901234',
-            'name': b'v0.0.1',
-            'author': {
-                'name': b'olasd',
-                'email': b'nic@olasd.fr',
-                'fullname': b'olasd <nic@olasd.fr>',
-            },
-            'date': {
-                'timestamp': 1234567890,
-                'offset': 42,
-                'negative_utc': None,
-            },
-            'target': b'43210987654321098765',
-            'target_type': 'revision',
-            'message': b'synthetic release',
-            'synthetic': True,
-        }
-
-        self.release2 = {
-            'id': b'56789012348765901234',
-            'name': b'v0.0.2',
-            'author': {
-                'name': b'tony',
-                'email': b'ar@dumont.fr',
-                'fullname': b'tony <ar@dumont.fr>',
-            },
-            'date': {
-                'timestamp': 1634366813,
-                'offset': -120,
-                'negative_utc': None,
-            },
-            'target': b'432109\xa9765432\xc309\x00765',
-            'target_type': 'revision',
-            'message': b'v0.0.2\nMisc performance improvements + bug fixes',
-            'synthetic': False
-        }
-
-        self.release3 = {
-            'id': b'87659012345678904321',
-            'name': b'v0.0.2',
-            'author': {
-                'name': b'tony',
-                'email': b'tony@ardumont.fr',
-                'fullname': b'tony <tony@ardumont.fr>',
-            },
-            'date': {
-                'timestamp': 1634336813,
-                'offset': 0,
-                'negative_utc': False,
-            },
-            'target': self.revision2['id'],
-            'target_type': 'revision',
-            'message': b'yet another synthetic release',
-            'synthetic': True,
-        }
-
-        self.fetch_history_date = datetime.datetime(
-            2015, 1, 2, 21, 0, 0,
-            tzinfo=datetime.timezone.utc)
-        self.fetch_history_end = datetime.datetime(
-            2015, 1, 2, 23, 0, 0,
-            tzinfo=datetime.timezone.utc)
-
-        self.fetch_history_duration = (self.fetch_history_end -
-                                       self.fetch_history_date)
-
-        self.fetch_history_data = {
-            'status': True,
-            'result': {'foo': 'bar'},
-            'stdout': 'blabla',
-            'stderr': 'blablabla',
-        }
-
-        self.snapshot = {
-            'id': hash_to_bytes('2498dbf535f882bc7f9a18fb16c9ad27fda7bab7'),
-            'branches': {
-                b'master': {
-                    'target': self.revision['id'],
-                    'target_type': 'revision',
-                },
-            },
-        }
-
-        self.empty_snapshot = {
-            'id': hash_to_bytes('1a8893e6a86f444e8be8e7bda6cb34fb1735a00e'),
-            'branches': {},
-        }
-
-        self.complete_snapshot = {
-            'id': hash_to_bytes('6e65b86363953b780d92b0a928f3e8fcdd10db36'),
-            'branches': {
-                b'directory': {
-                    'target': hash_to_bytes(
-                        '1bd0e65f7d2ff14ae994de17a1e7fe65111dcad8'),
-                    'target_type': 'directory',
-                },
-                b'directory2': {
-                    'target': hash_to_bytes(
-                        '1bd0e65f7d2ff14ae994de17a1e7fe65111dcad8'),
-                    'target_type': 'directory',
-                },
-                b'content': {
-                    'target': hash_to_bytes(
-                        'fe95a46679d128ff167b7c55df5d02356c5a1ae1'),
-                    'target_type': 'content',
-                },
-                b'alias': {
-                    'target': b'revision',
-                    'target_type': 'alias',
-                },
-                b'revision': {
-                    'target': hash_to_bytes(
-                        'aafb16d69fd30ff58afdd69036a26047f3aebdc6'),
-                    'target_type': 'revision',
-                },
-                b'release': {
-                    'target': hash_to_bytes(
-                        '7045404f3d1c54e6473c71bbb716529fbad4be24'),
-                    'target_type': 'release',
-                },
-                b'snapshot': {
-                    'target': hash_to_bytes(
-                        '1a8893e6a86f444e8be8e7bda6cb34fb1735a00e'),
-                    'target_type': 'snapshot',
-                },
-                b'dangling': None,
-            },
-        }
-
-
-class CommonTestStorage(TestStorageData):
-    """Base class for Storage testing.
+class TestStorage:
+    """Main class for Storage testing.
 
     This class is used as-is to test local storage (see TestLocalStorage
     below) and remote storage (see TestRemoteStorage in
     test_remote_storage.py.
 
     We need to have the two classes inherit from this base class
     separately to avoid nosetests running the tests from the base
     class twice.
-
     """
     maxDiff = None  # type: ClassVar[Optional[int]]
     _test_origin_ids = True
 
-    @staticmethod
-    def normalize_entity(entity):
-        entity = copy.deepcopy(entity)
-        for key in ('date', 'committer_date'):
-            if key in entity:
-                entity[key] = identifiers.normalize_timestamp(entity[key])
-
-        return entity
+    def test_check_config(self, swh_storage):
+        assert swh_storage.check_config(check_write=True)
+        assert swh_storage.check_config(check_write=False)
 
-    def test_check_config(self):
-        self.assertTrue(self.storage.check_config(check_write=True))
-        self.assertTrue(self.storage.check_config(check_write=False))
-
-    def test_content_add(self):
-        cont = self.cont
+    def test_content_add(self, swh_storage):
+        cont = data.cont
 
         insertion_start_time = datetime.datetime.now(tz=datetime.timezone.utc)
-        actual_result = self.storage.content_add([cont])
+        actual_result = swh_storage.content_add([cont])
         insertion_end_time = datetime.datetime.now(tz=datetime.timezone.utc)
 
-        self.assertEqual(actual_result, {
+        assert actual_result == {
             'content:add': 1,
             'content:add:bytes': cont['length'],
             'skipped_content:add': 0
-        })
+        }
 
-        self.assertEqual(list(self.storage.content_get([cont['sha1']])),
-                         [{'sha1': cont['sha1'], 'data': cont['data']}])
+        assert list(swh_storage.content_get([cont['sha1']])) == \
+            [{'sha1': cont['sha1'], 'data': cont['data']}]
 
-        expected_cont = cont.copy()
+        expected_cont = data.cont
         del expected_cont['data']
-        journal_objects = list(self.journal_writer.objects)
+        journal_objects = list(swh_storage.journal_writer.objects)
         for (obj_type, obj) in journal_objects:
-            self.assertLessEqual(insertion_start_time, obj['ctime'])
-            self.assertLessEqual(obj['ctime'], insertion_end_time)
+            assert insertion_start_time <= obj['ctime']
+            assert obj['ctime'] <= insertion_end_time
             del obj['ctime']
-        self.assertEqual(journal_objects,
-                         [('content', expected_cont)])
+        assert journal_objects == [('content', expected_cont)]
 
-    def test_content_add_validation(self):
-        cont = self.cont
+    def test_content_add_validation(self, swh_storage):
+        cont = data.cont
 
-        with self.assertRaisesRegex(ValueError, 'status'):
-            self.storage.content_add([{**cont, 'status': 'foobar'}])
+        with pytest.raises(ValueError, match='status'):
+            swh_storage.content_add([{**cont, 'status': 'foobar'}])
 
-        with self.assertRaisesRegex(ValueError, "(?i)length"):
-            self.storage.content_add([{**cont, 'length': -2}])
+        with pytest.raises(ValueError, match="(?i)length"):
+            swh_storage.content_add([{**cont, 'length': -2}])
 
-        with self.assertRaisesRegex(
-                (ValueError, psycopg2.IntegrityError), 'reason') as cm:
-            self.storage.content_add([{**cont, 'status': 'absent'}])
+        with pytest.raises((ValueError, psycopg2.IntegrityError),
+                           match='reason') as cm:
+            swh_storage.content_add([{**cont, 'status': 'absent'}])
 
-        if type(cm.exception) == psycopg2.IntegrityError:
-            self.assertEqual(cm.exception.pgcode,
-                             psycopg2.errorcodes.NOT_NULL_VIOLATION)
+        if type(cm.value) == psycopg2.IntegrityError:
+            assert cm.exception.pgcode == \
+                psycopg2.errorcodes.NOT_NULL_VIOLATION
 
-        with self.assertRaisesRegex(
+        with pytest.raises(
                 ValueError,
-                "^Must not provide a reason if content is not absent.$"):
-            self.storage.content_add([{**cont, 'reason': 'foobar'}])
+                match="^Must not provide a reason if content is not absent.$"):
+            swh_storage.content_add([{**cont, 'reason': 'foobar'}])
 
-    def test_content_get_missing(self):
-        cont = self.cont
+    def test_content_get_missing(self, swh_storage):
+        cont = data.cont
 
-        self.storage.content_add([cont])
+        swh_storage.content_add([cont])
 
         # Query a single missing content
-        results = list(self.storage.content_get(
-            [self.cont2['sha1']]))
-        self.assertEqual(results,
-                         [None])
+        results = list(swh_storage.content_get(
+            [data.cont2['sha1']]))
+        assert results == [None]
 
         # Check content_get does not abort after finding a missing content
-        results = list(self.storage.content_get(
-            [self.cont['sha1'], self.cont2['sha1']]))
-        self.assertEqual(results,
-                         [{'sha1': cont['sha1'], 'data': cont['data']}, None])
+        results = list(swh_storage.content_get(
+            [data.cont['sha1'], data.cont2['sha1']]))
+        assert results == [{'sha1': cont['sha1'], 'data': cont['data']}, None]
 
         # Check content_get does not discard found countent when it finds
         # a missing content.
-        results = list(self.storage.content_get(
-            [self.cont2['sha1'], self.cont['sha1']]))
-        self.assertEqual(results,
-                         [None, {'sha1': cont['sha1'], 'data': cont['data']}])
+        results = list(swh_storage.content_get(
+            [data.cont2['sha1'], data.cont['sha1']]))
+        assert results == [None, {'sha1': cont['sha1'], 'data': cont['data']}]
 
-    def test_content_add_same_input(self):
-        cont = self.cont
+    def test_content_add_same_input(self, swh_storage):
+        cont = data.cont
 
-        actual_result = self.storage.content_add([cont, cont])
-        self.assertEqual(actual_result, {
+        actual_result = swh_storage.content_add([cont, cont])
+        assert actual_result == {
             'content:add': 1,
             'content:add:bytes': cont['length'],
             'skipped_content:add': 0
-        })
+            }
 
-    def test_content_add_different_input(self):
-        cont = self.cont
-        cont2 = self.cont2
+    def test_content_add_different_input(self, swh_storage):
+        cont = data.cont
+        cont2 = data.cont2
 
-        actual_result = self.storage.content_add([cont, cont2])
-        self.assertEqual(actual_result, {
+        actual_result = swh_storage.content_add([cont, cont2])
+        assert actual_result == {
             'content:add': 2,
             'content:add:bytes': cont['length'] + cont2['length'],
             'skipped_content:add': 0
-        })
-
-    def test_content_add_twice(self):
-        actual_result = self.storage.content_add([self.cont])
-        self.assertEqual(actual_result, {
-            'content:add': 1,
-            'content:add:bytes': self.cont['length'],
-            'skipped_content:add': 0
-        })
-        self.assertEqual(len(self.journal_writer.objects), 1)
+            }
 
-        actual_result = self.storage.content_add([self.cont, self.cont2])
-        self.assertEqual(actual_result, {
+    def test_content_add_twice(self, swh_storage):
+        actual_result = swh_storage.content_add([data.cont])
+        assert actual_result == {
             'content:add': 1,
-            'content:add:bytes': self.cont2['length'],
+            'content:add:bytes': data.cont['length'],
             'skipped_content:add': 0
-        })
-        self.assertEqual(len(self.journal_writer.objects), 2)
-
-        self.assertEqual(len(self.storage.content_find(self.cont)), 1)
-        self.assertEqual(len(self.storage.content_find(self.cont2)), 1)
-
-    def test_content_add_db(self):
-        cont = self.cont
-
-        actual_result = self.storage.content_add([cont])
+            }
+        assert len(swh_storage.journal_writer.objects) == 1
 
-        self.assertEqual(actual_result, {
+        actual_result = swh_storage.content_add([data.cont, data.cont2])
+        assert actual_result == {
             'content:add': 1,
-            'content:add:bytes': cont['length'],
+            'content:add:bytes': data.cont2['length'],
             'skipped_content:add': 0
-        })
-
-        if hasattr(self.storage, 'objstorage'):
-            self.assertIn(cont['sha1'], self.storage.objstorage)
-
-        with self.db_transaction() as (_, cur):
-            cur.execute('SELECT sha1, sha1_git, sha256, length, status'
-                        ' FROM content WHERE sha1 = %s',
-                        (cont['sha1'],))
-            datum = cur.fetchone()
-
-        self.assertEqual(
-            datum,
-            (cont['sha1'], cont['sha1_git'], cont['sha256'],
-             cont['length'], 'visible'))
+            }
+        assert len(swh_storage.journal_writer.objects) == 2
 
-        expected_cont = cont.copy()
-        del expected_cont['data']
-        journal_objects = list(self.journal_writer.objects)
-        for (obj_type, obj) in journal_objects:
-            del obj['ctime']
-        self.assertEqual(journal_objects,
-                         [('content', expected_cont)])
+        assert len(swh_storage.content_find(data.cont)) == 1
+        assert len(swh_storage.content_find(data.cont2)) == 1
 
-    def test_content_add_collision(self):
-        cont1 = self.cont
+    def test_content_add_collision(self, swh_storage):
+        cont1 = data.cont
 
         # create (corrupted) content with same sha1{,_git} but != sha256
         cont1b = cont1.copy()
         sha256_array = bytearray(cont1b['sha256'])
         sha256_array[0] += 1
         cont1b['sha256'] = bytes(sha256_array)
 
-        with self.assertRaises(HashCollision) as cm:
-            self.storage.content_add([cont1, cont1b])
+        with pytest.raises(HashCollision) as cm:
+            swh_storage.content_add([cont1, cont1b])
 
-        self.assertIn(cm.exception.args[0], ['sha1', 'sha1_git', 'blake2s256'])
+        assert cm.value.args[0] in ['sha1', 'sha1_git', 'blake2s256']
 
-    def test_content_add_metadata(self):
-        cont = self.cont.copy()
+    def test_content_add_metadata(self, swh_storage):
+        cont = data.cont
         del cont['data']
         cont['ctime'] = datetime.datetime.now()
 
-        actual_result = self.storage.content_add_metadata([cont])
-        self.assertEqual(actual_result, {
+        actual_result = swh_storage.content_add_metadata([cont])
+        assert actual_result == {
             'content:add': 1,
             'skipped_content:add': 0
-        })
+            }
 
         expected_cont = cont.copy()
         del expected_cont['ctime']
-        self.assertEqual(
-            list(self.storage.content_get_metadata([cont['sha1']])),
-            [expected_cont])
+        assert list(swh_storage.content_get_metadata([cont['sha1']])) == \
+            [expected_cont]
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('content', cont)])
+        assert list(swh_storage.journal_writer.objects) == [('content', cont)]
 
-    def test_content_add_metadata_same_input(self):
-        cont = self.cont.copy()
+    def test_content_add_metadata_same_input(self, swh_storage):
+        cont = data.cont
         del cont['data']
         cont['ctime'] = datetime.datetime.now()
 
-        actual_result = self.storage.content_add_metadata([cont, cont])
-        self.assertEqual(actual_result, {
+        actual_result = swh_storage.content_add_metadata([cont, cont])
+        assert actual_result == {
             'content:add': 1,
             'skipped_content:add': 0
-        })
+            }
 
-    def test_content_add_metadata_different_input(self):
-        cont = self.cont.copy()
+    def test_content_add_metadata_different_input(self, swh_storage):
+        cont = data.cont
         del cont['data']
         cont['ctime'] = datetime.datetime.now()
-        cont2 = self.cont2.copy()
+        cont2 = data.cont2
         del cont2['data']
         cont2['ctime'] = datetime.datetime.now()
 
-        actual_result = self.storage.content_add_metadata([cont, cont2])
-        self.assertEqual(actual_result, {
+        actual_result = swh_storage.content_add_metadata([cont, cont2])
+        assert actual_result == {
             'content:add': 2,
             'skipped_content:add': 0
-        })
-
-    def test_content_add_metadata_db(self):
-        cont = self.cont.copy()
-        del cont['data']
-        cont['ctime'] = datetime.datetime.now()
-
-        actual_result = self.storage.content_add_metadata([cont])
-
-        self.assertEqual(actual_result, {
-            'content:add': 1,
-            'skipped_content:add': 0
-        })
-
-        if hasattr(self.storage, 'objstorage'):
-            self.assertNotIn(cont['sha1'], self.storage.objstorage)
-
-        with self.db_transaction() as (_, cur):
-            cur.execute('SELECT sha1, sha1_git, sha256, length, status'
-                        ' FROM content WHERE sha1 = %s',
-                        (cont['sha1'],))
-            datum = cur.fetchone()
-
-        self.assertEqual(
-            datum,
-            (cont['sha1'], cont['sha1_git'], cont['sha256'],
-             cont['length'], 'visible'))
-
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('content', cont)])
+            }
 
-    def test_content_add_metadata_collision(self):
-        cont1 = self.cont.copy()
+    def test_content_add_metadata_collision(self, swh_storage):
+        cont1 = data.cont
         del cont1['data']
         cont1['ctime'] = datetime.datetime.now()
 
         # create (corrupted) content with same sha1{,_git} but != sha256
         cont1b = cont1.copy()
         sha256_array = bytearray(cont1b['sha256'])
         sha256_array[0] += 1
         cont1b['sha256'] = bytes(sha256_array)
 
-        with self.assertRaises(HashCollision) as cm:
-            self.storage.content_add_metadata([cont1, cont1b])
-
-        self.assertIn(cm.exception.args[0], ['sha1', 'sha1_git', 'blake2s256'])
-
-    def test_skipped_content_add_db(self):
-        cont = self.skipped_cont.copy()
-        cont2 = self.skipped_cont2.copy()
-        cont2['blake2s256'] = None
-
-        actual_result = self.storage.content_add([cont, cont, cont2])
-
-        self.assertEqual(actual_result, {
-            'content:add': 0,
-            'content:add:bytes': 0,
-            'skipped_content:add': 2,
-        })
-
-        with self.db_transaction() as (_, cur):
-            cur.execute('SELECT sha1, sha1_git, sha256, blake2s256, '
-                        'length, status, reason '
-                        'FROM skipped_content ORDER BY sha1_git')
-
-            data = cur.fetchall()
-
-        self.assertEqual(2, len(data))
-        self.assertEqual(
-            data[0],
-            (cont['sha1'], cont['sha1_git'], cont['sha256'],
-             cont['blake2s256'], cont['length'], 'absent',
-             'Content too long')
-        )
+        with pytest.raises(HashCollision) as cm:
+            swh_storage.content_add_metadata([cont1, cont1b])
 
-        self.assertEqual(
-            data[1],
-            (cont2['sha1'], cont2['sha1_git'], cont2['sha256'],
-             cont2['blake2s256'], cont2['length'], 'absent',
-             'Content too long')
-        )
+        assert cm.value.args[0] in ['sha1', 'sha1_git', 'blake2s256']
 
-    def test_skipped_content_add(self):
-        cont = self.skipped_cont.copy()
-        cont2 = self.skipped_cont2.copy()
+    def test_skipped_content_add(self, swh_storage):
+        cont = data.skipped_cont
+        cont2 = data.skipped_cont2
         cont2['blake2s256'] = None
 
-        missing = list(self.storage.skipped_content_missing([cont, cont2]))
+        missing = list(swh_storage.skipped_content_missing([cont, cont2]))
 
-        self.assertEqual(len(missing), 2, missing)
+        assert len(missing) == 2
 
-        actual_result = self.storage.content_add([cont, cont, cont2])
+        actual_result = swh_storage.content_add([cont, cont, cont2])
 
-        self.assertEqual(actual_result, {
+        assert actual_result == {
             'content:add': 0,
             'content:add:bytes': 0,
             'skipped_content:add': 2,
-        })
+            }
 
-        missing = list(self.storage.skipped_content_missing([cont, cont2]))
+        missing = list(swh_storage.skipped_content_missing([cont, cont2]))
 
-        self.assertEqual(missing, [])
+        assert missing == []
 
     @pytest.mark.property_based
     @settings(deadline=None)  # this test is very slow
     @given(strategies.sets(
         elements=strategies.sampled_from(
             ['sha256', 'sha1_git', 'blake2s256']),
         min_size=0))
-    def test_content_missing(self, algos):
+    def test_content_missing(self, swh_storage, algos):
         algos |= {'sha1'}
-        cont2 = self.cont2
-        missing_cont = self.missing_cont
-        self.storage.content_add([cont2])
+        cont2 = data.cont2
+        missing_cont = data.missing_cont
+        swh_storage.content_add([cont2])
         test_contents = [cont2]
         missing_per_hash = defaultdict(list)
         for i in range(256):
             test_content = missing_cont.copy()
             for hash in algos:
                 test_content[hash] = bytes([i]) + test_content[hash][1:]
                 missing_per_hash[hash].append(test_content[hash])
             test_contents.append(test_content)
 
-        self.assertCountEqual(
-            self.storage.content_missing(test_contents),
-            missing_per_hash['sha1']
-        )
+        assert set(swh_storage.content_missing(test_contents)) == \
+            set(missing_per_hash['sha1'])
 
         for hash in algos:
-            self.assertCountEqual(
-                self.storage.content_missing(test_contents, key_hash=hash),
-                missing_per_hash[hash]
-            )
+            assert set(swh_storage.content_missing(
+                test_contents, key_hash=hash)) == set(missing_per_hash[hash])
 
     @pytest.mark.property_based
     @given(strategies.sets(
         elements=strategies.sampled_from(
             ['sha256', 'sha1_git', 'blake2s256']),
         min_size=0))
-    def test_content_missing_unknown_algo(self, algos):
+    def test_content_missing_unknown_algo(self, swh_storage, algos):
         algos |= {'sha1'}
-        cont2 = self.cont2
-        missing_cont = self.missing_cont
-        self.storage.content_add([cont2])
+        cont2 = data.cont2
+        missing_cont = data.missing_cont
+        swh_storage.content_add([cont2])
         test_contents = [cont2]
         missing_per_hash = defaultdict(list)
         for i in range(16):
             test_content = missing_cont.copy()
             for hash in algos:
                 test_content[hash] = bytes([i]) + test_content[hash][1:]
                 missing_per_hash[hash].append(test_content[hash])
             test_content['nonexisting_algo'] = b'\x00'
             test_contents.append(test_content)
 
-        self.assertCountEqual(
-            self.storage.content_missing(test_contents),
-            missing_per_hash['sha1']
-        )
+        assert set(
+            swh_storage.content_missing(test_contents)) == set(
+            missing_per_hash['sha1'])
 
         for hash in algos:
-            self.assertCountEqual(
-                self.storage.content_missing(test_contents, key_hash=hash),
-                missing_per_hash[hash]
-            )
+            assert set(swh_storage.content_missing(
+                test_contents, key_hash=hash)) == set(
+                missing_per_hash[hash])
 
-    def test_content_missing_per_sha1(self):
+    def test_content_missing_per_sha1(self, swh_storage):
         # given
-        cont2 = self.cont2
-        missing_cont = self.missing_cont
-        self.storage.content_add([cont2])
+        cont2 = data.cont2
+        missing_cont = data.missing_cont
+        swh_storage.content_add([cont2])
         # when
-        gen = self.storage.content_missing_per_sha1([cont2['sha1'],
-                                                     missing_cont['sha1']])
-
+        gen = swh_storage.content_missing_per_sha1([cont2['sha1'],
+                                                    missing_cont['sha1']])
         # then
-        self.assertEqual(list(gen), [missing_cont['sha1']])
+        assert list(gen) == [missing_cont['sha1']]
 
-    def test_content_get_metadata(self):
-        cont1 = self.cont.copy()
-        cont2 = self.cont2.copy()
+    def test_content_get_metadata(self, swh_storage):
+        cont1 = data.cont
+        cont2 = data.cont2
 
-        self.storage.content_add([cont1, cont2])
+        swh_storage.content_add([cont1, cont2])
 
-        gen = self.storage.content_get_metadata([cont1['sha1'], cont2['sha1']])
+        actual_md = list(swh_storage.content_get_metadata(
+            [cont1['sha1'], cont2['sha1']]))
 
         # we only retrieve the metadata
         cont1.pop('data')
         cont2.pop('data')
 
-        self.assertCountEqual(list(gen), [cont1, cont2])
-
-    def test_content_get_metadata_missing_sha1(self):
-        cont1 = self.cont.copy()
-        cont2 = self.cont2.copy()
+        assert actual_md in ([cont1, cont2], [cont2, cont1])
 
-        missing_cont = self.missing_cont.copy()
+    def test_content_get_metadata_missing_sha1(self, swh_storage):
+        cont1 = data.cont
+        cont2 = data.cont2
+        missing_cont = data.missing_cont
 
-        self.storage.content_add([cont1, cont2])
+        swh_storage.content_add([cont1, cont2])
 
-        gen = self.storage.content_get_metadata([missing_cont['sha1']])
+        gen = swh_storage.content_get_metadata([missing_cont['sha1']])
 
         # All the metadata keys are None
         missing_cont.pop('data')
-        for key in list(missing_cont):
+        for key in missing_cont:
             if key != 'sha1':
                 missing_cont[key] = None
 
-        self.assertEqual(list(gen), [missing_cont])
-
-    @staticmethod
-    def _transform_entries(dir_, *, prefix=b''):
-        for ent in dir_['entries']:
-            yield {
-                'dir_id': dir_['id'],
-                'type': ent['type'],
-                'target': ent['target'],
-                'name': prefix + ent['name'],
-                'perms': ent['perms'],
-                'status': None,
-                'sha1': None,
-                'sha1_git': None,
-                'sha256': None,
-                'length': None,
-            }
+        assert list(gen) == [missing_cont]
 
-    def test_directory_add(self):
-        init_missing = list(self.storage.directory_missing([self.dir['id']]))
-        self.assertEqual([self.dir['id']], init_missing)
+    def test_directory_add(self, swh_storage):
+        init_missing = list(swh_storage.directory_missing([data.dir['id']]))
+        assert [data.dir['id']] == init_missing
 
-        actual_result = self.storage.directory_add([self.dir])
-        self.assertEqual(actual_result, {'directory:add': 1})
+        actual_result = swh_storage.directory_add([data.dir])
+        assert actual_result == {'directory:add': 1}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('directory', self.dir)])
+        assert list(swh_storage.journal_writer.objects) == \
+            [('directory', data.dir)]
 
-        actual_data = list(self.storage.directory_ls(self.dir['id']))
-        expected_data = list(self._transform_entries(self.dir))
-        self.assertCountEqual(expected_data, actual_data)
+        actual_data = list(swh_storage.directory_ls(data.dir['id']))
+        expected_data = list(transform_entries(data.dir))
 
-        after_missing = list(self.storage.directory_missing([self.dir['id']]))
-        self.assertEqual([], after_missing)
+        assert sorted(expected_data, key=cmpdir) \
+            == sorted(actual_data, key=cmpdir)
 
-    def test_directory_add_validation(self):
-        dir_ = copy.deepcopy(self.dir)
+        after_missing = list(swh_storage.directory_missing([data.dir['id']]))
+        assert after_missing == []
+
+    def test_directory_add_validation(self, swh_storage):
+        dir_ = copy.deepcopy(data.dir)
         dir_['entries'][0]['type'] = 'foobar'
 
-        with self.assertRaisesRegex(ValueError, 'type.*foobar'):
-            self.storage.directory_add([dir_])
+        with pytest.raises(ValueError, match='type.*foobar'):
+            swh_storage.directory_add([dir_])
 
-        dir_ = copy.deepcopy(self.dir)
+        dir_ = copy.deepcopy(data.dir)
         del dir_['entries'][0]['target']
 
-        with self.assertRaisesRegex(
-                (TypeError, psycopg2.IntegrityError), 'target') as cm:
-            self.storage.directory_add([dir_])
+        with pytest.raises((TypeError, psycopg2.IntegrityError),
+                           match='target') as cm:
+            swh_storage.directory_add([dir_])
 
-        if type(cm.exception) == psycopg2.IntegrityError:
-            self.assertEqual(cm.exception.pgcode,
-                             psycopg2.errorcodes.NOT_NULL_VIOLATION)
+        if type(cm.value) == psycopg2.IntegrityError:
+            assert cm.value.pgcode == psycopg2.errorcodes.NOT_NULL_VIOLATION
 
-    def test_directory_add_twice(self):
-        actual_result = self.storage.directory_add([self.dir])
-        self.assertEqual(actual_result, {'directory:add': 1})
+    def test_directory_add_twice(self, swh_storage):
+        actual_result = swh_storage.directory_add([data.dir])
+        assert actual_result == {'directory:add': 1}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('directory', self.dir)])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('directory', data.dir)]
 
-        actual_result = self.storage.directory_add([self.dir])
-        self.assertEqual(actual_result, {'directory:add': 0})
+        actual_result = swh_storage.directory_add([data.dir])
+        assert actual_result == {'directory:add': 0}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('directory', self.dir)])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('directory', data.dir)]
 
-    def test_directory_get_recursive(self):
-        init_missing = list(self.storage.directory_missing([self.dir['id']]))
-        self.assertEqual([self.dir['id']], init_missing)
+    def test_directory_get_recursive(self, swh_storage):
+        init_missing = list(swh_storage.directory_missing([data.dir['id']]))
+        assert init_missing == [data.dir['id']]
 
-        actual_result = self.storage.directory_add(
-            [self.dir, self.dir2, self.dir3])
-        self.assertEqual(actual_result, {'directory:add': 3})
+        actual_result = swh_storage.directory_add(
+            [data.dir, data.dir2, data.dir3])
+        assert actual_result == {'directory:add': 3}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('directory', self.dir),
-                          ('directory', self.dir2),
-                          ('directory', self.dir3)])
+        assert list(swh_storage.journal_writer.objects) == [
+            ('directory', data.dir),
+            ('directory', data.dir2),
+            ('directory', data.dir3)]
 
         # List directory containing a file and an unknown subdirectory
-        actual_data = list(self.storage.directory_ls(
-            self.dir['id'], recursive=True))
-        expected_data = list(self._transform_entries(self.dir))
-        self.assertCountEqual(expected_data, actual_data)
+        actual_data = list(swh_storage.directory_ls(
+            data.dir['id'], recursive=True))
+        expected_data = list(transform_entries(data.dir))
+        assert sorted(expected_data, key=cmpdir) \
+            == sorted(actual_data, key=cmpdir)
 
         # List directory containing a file and an unknown subdirectory
-        actual_data = list(self.storage.directory_ls(
-            self.dir2['id'], recursive=True))
-        expected_data = list(self._transform_entries(self.dir2))
-        self.assertCountEqual(expected_data, actual_data)
+        actual_data = list(swh_storage.directory_ls(
+            data.dir2['id'], recursive=True))
+        expected_data = list(transform_entries(data.dir2))
+        assert sorted(expected_data, key=cmpdir) \
+            == sorted(actual_data, key=cmpdir)
 
         # List directory containing a known subdirectory, entries should
         # be both those of the directory and of the subdir
-        actual_data = list(self.storage.directory_ls(
-            self.dir3['id'], recursive=True))
+        actual_data = list(swh_storage.directory_ls(
+            data.dir3['id'], recursive=True))
         expected_data = list(itertools.chain(
-            self._transform_entries(self.dir3),
-            self._transform_entries(self.dir, prefix=b'subdir/')))
-        self.assertCountEqual(expected_data, actual_data)
+            transform_entries(data.dir3),
+            transform_entries(data.dir, prefix=b'subdir/')))
+        assert sorted(expected_data, key=cmpdir) \
+            == sorted(actual_data, key=cmpdir)
 
-    def test_directory_get_non_recursive(self):
-        init_missing = list(self.storage.directory_missing([self.dir['id']]))
-        self.assertEqual([self.dir['id']], init_missing)
+    def test_directory_get_non_recursive(self, swh_storage):
+        init_missing = list(swh_storage.directory_missing([data.dir['id']]))
+        assert init_missing == [data.dir['id']]
 
-        actual_result = self.storage.directory_add(
-            [self.dir, self.dir2, self.dir3])
-        self.assertEqual(actual_result, {'directory:add': 3})
+        actual_result = swh_storage.directory_add(
+            [data.dir, data.dir2, data.dir3])
+        assert actual_result == {'directory:add': 3}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('directory', self.dir),
-                          ('directory', self.dir2),
-                          ('directory', self.dir3)])
+        assert list(swh_storage.journal_writer.objects) == [
+            ('directory', data.dir),
+            ('directory', data.dir2),
+            ('directory', data.dir3)]
 
         # List directory containing a file and an unknown subdirectory
-        actual_data = list(self.storage.directory_ls(self.dir['id']))
-        expected_data = list(self._transform_entries(self.dir))
-        self.assertCountEqual(expected_data, actual_data)
+        actual_data = list(swh_storage.directory_ls(data.dir['id']))
+        expected_data = list(transform_entries(data.dir))
+        assert sorted(expected_data, key=cmpdir) \
+            == sorted(actual_data, key=cmpdir)
 
         # List directory contaiining a single file
-        actual_data = list(self.storage.directory_ls(self.dir2['id']))
-        expected_data = list(self._transform_entries(self.dir2))
-        self.assertCountEqual(expected_data, actual_data)
+        actual_data = list(swh_storage.directory_ls(data.dir2['id']))
+        expected_data = list(transform_entries(data.dir2))
+        assert sorted(expected_data, key=cmpdir) \
+            == sorted(actual_data, key=cmpdir)
 
         # List directory containing a known subdirectory, entries should
         # only be those of the parent directory, not of the subdir
-        actual_data = list(self.storage.directory_ls(self.dir3['id']))
-        expected_data = list(self._transform_entries(self.dir3))
-        self.assertCountEqual(expected_data, actual_data)
+        actual_data = list(swh_storage.directory_ls(data.dir3['id']))
+        expected_data = list(transform_entries(data.dir3))
+        assert sorted(expected_data, key=cmpdir) \
+            == sorted(actual_data, key=cmpdir)
 
-    def test_directory_entry_get_by_path(self):
+    def test_directory_entry_get_by_path(self, swh_storage):
         # given
-        init_missing = list(self.storage.directory_missing([self.dir3['id']]))
-        self.assertEqual([self.dir3['id']], init_missing)
+        init_missing = list(swh_storage.directory_missing([data.dir3['id']]))
+        assert [data.dir3['id']] == init_missing
 
-        actual_result = self.storage.directory_add([self.dir3, self.dir4])
-        self.assertEqual(actual_result, {'directory:add': 2})
+        actual_result = swh_storage.directory_add([data.dir3, data.dir4])
+        assert actual_result == {'directory:add': 2}
 
         expected_entries = [
             {
-                'dir_id': self.dir3['id'],
+                'dir_id': data.dir3['id'],
                 'name': b'foo',
                 'type': 'file',
-                'target': self.cont['sha1_git'],
+                'target': data.cont['sha1_git'],
                 'sha1': None,
                 'sha1_git': None,
                 'sha256': None,
                 'status': None,
                 'perms': from_disk.DentryPerms.content,
                 'length': None,
             },
             {
-                'dir_id': self.dir3['id'],
+                'dir_id': data.dir3['id'],
                 'name': b'subdir',
                 'type': 'dir',
-                'target': self.dir['id'],
+                'target': data.dir['id'],
                 'sha1': None,
                 'sha1_git': None,
                 'sha256': None,
                 'status': None,
                 'perms': from_disk.DentryPerms.directory,
                 'length': None,
             },
             {
-                'dir_id': self.dir3['id'],
+                'dir_id': data.dir3['id'],
                 'name': b'hello',
                 'type': 'file',
                 'target': b'12345678901234567890',
                 'sha1': None,
                 'sha1_git': None,
                 'sha256': None,
                 'status': None,
                 'perms': from_disk.DentryPerms.content,
                 'length': None,
             },
         ]
 
         # when (all must be found here)
-        for entry, expected_entry in zip(self.dir3['entries'],
-                                         expected_entries):
-            actual_entry = self.storage.directory_entry_get_by_path(
-                self.dir3['id'],
+        for entry, expected_entry in zip(
+                data.dir3['entries'], expected_entries):
+            actual_entry = swh_storage.directory_entry_get_by_path(
+                data.dir3['id'],
                 [entry['name']])
-            self.assertEqual(actual_entry, expected_entry)
+            assert actual_entry == expected_entry
 
         # same, but deeper
-        for entry, expected_entry in zip(self.dir3['entries'],
-                                         expected_entries):
-            actual_entry = self.storage.directory_entry_get_by_path(
-                self.dir4['id'],
+        for entry, expected_entry in zip(
+                data.dir3['entries'], expected_entries):
+            actual_entry = swh_storage.directory_entry_get_by_path(
+                data.dir4['id'],
                 [b'subdir1', entry['name']])
             expected_entry = expected_entry.copy()
             expected_entry['name'] = b'subdir1/' + expected_entry['name']
-            self.assertEqual(actual_entry, expected_entry)
+            assert actual_entry == expected_entry
 
-        # when (nothing should be found here since self.dir is not persisted.)
-        for entry in self.dir['entries']:
-            actual_entry = self.storage.directory_entry_get_by_path(
-                self.dir['id'],
+        # when (nothing should be found here since data.dir is not persisted.)
+        for entry in data.dir['entries']:
+            actual_entry = swh_storage.directory_entry_get_by_path(
+                data.dir['id'],
                 [entry['name']])
-            self.assertIsNone(actual_entry)
+            assert actual_entry is None
+
+    def test_revision_add(self, swh_storage):
+        init_missing = swh_storage.revision_missing([data.revision['id']])
+        assert list(init_missing) == [data.revision['id']]
 
-    def test_revision_add(self):
-        init_missing = self.storage.revision_missing([self.revision['id']])
-        self.assertEqual([self.revision['id']], list(init_missing))
+        actual_result = swh_storage.revision_add([data.revision])
+        assert actual_result == {'revision:add': 1}
 
-        actual_result = self.storage.revision_add([self.revision])
-        self.assertEqual(actual_result, {'revision:add': 1})
+        end_missing = swh_storage.revision_missing([data.revision['id']])
+        assert list(end_missing) == []
 
-        end_missing = self.storage.revision_missing([self.revision['id']])
-        self.assertEqual([], list(end_missing))
+        assert list(swh_storage.journal_writer.objects) \
+            == [('revision', data.revision)]
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('revision', self.revision)])
+        # already there so nothing added
+        actual_result = swh_storage.revision_add([data.revision])
+        assert actual_result == {'revision:add': 0}
 
-    def test_revision_add_validation(self):
-        rev = copy.deepcopy(self.revision)
+    def test_revision_add_validation(self, swh_storage):
+        rev = copy.deepcopy(data.revision)
         rev['date']['offset'] = 2**16
 
-        with self.assertRaisesRegex(
-                (ValueError, psycopg2.DataError), 'offset') as cm:
-            self.storage.revision_add([rev])
+        with pytest.raises((ValueError, psycopg2.DataError),
+                           match='offset') as cm:
+            swh_storage.revision_add([rev])
 
-        if type(cm.exception) == psycopg2.DataError:
-            self.assertEqual(cm.exception.pgcode,
-                             psycopg2.errorcodes.NUMERIC_VALUE_OUT_OF_RANGE)
+        if type(cm.value) == psycopg2.DataError:
+            assert cm.value.pgcode \
+                == psycopg2.errorcodes.NUMERIC_VALUE_OUT_OF_RANGE
 
-        rev = copy.deepcopy(self.revision)
+        rev = copy.deepcopy(data.revision)
         rev['committer_date']['offset'] = 2**16
 
-        with self.assertRaisesRegex(
-                (ValueError, psycopg2.DataError), 'offset') as cm:
-            self.storage.revision_add([rev])
+        with pytest.raises((ValueError, psycopg2.DataError),
+                           match='offset') as cm:
+            swh_storage.revision_add([rev])
 
-        if type(cm.exception) == psycopg2.DataError:
-            self.assertEqual(cm.exception.pgcode,
-                             psycopg2.errorcodes.NUMERIC_VALUE_OUT_OF_RANGE)
+        if type(cm.value) == psycopg2.DataError:
+            assert cm.value.pgcode \
+                == psycopg2.errorcodes.NUMERIC_VALUE_OUT_OF_RANGE
 
-        rev = copy.deepcopy(self.revision)
+        rev = copy.deepcopy(data.revision)
         rev['type'] = 'foobar'
 
-        with self.assertRaisesRegex(
-                (ValueError, psycopg2.DataError), '(?i)type') as cm:
-            self.storage.revision_add([rev])
+        with pytest.raises((ValueError, psycopg2.DataError),
+                           match='(?i)type') as cm:
+            swh_storage.revision_add([rev])
 
-        if type(cm.exception) == psycopg2.DataError:
-            self.assertEqual(cm.exception.pgcode,
-                             psycopg2.errorcodes.INVALID_TEXT_REPRESENTATION)
+        if type(cm.value) == psycopg2.DataError:
+            assert cm.value.pgcode == \
+                psycopg2.errorcodes.INVALID_TEXT_REPRESENTATION
 
-    def test_revision_add_twice(self):
-        actual_result = self.storage.revision_add([self.revision])
-        self.assertEqual(actual_result, {'revision:add': 1})
+    def test_revision_add_twice(self, swh_storage):
+        actual_result = swh_storage.revision_add([data.revision])
+        assert actual_result == {'revision:add': 1}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('revision', self.revision)])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('revision', data.revision)]
 
-        actual_result = self.storage.revision_add(
-            [self.revision, self.revision2])
-        self.assertEqual(actual_result, {'revision:add': 1})
+        actual_result = swh_storage.revision_add(
+            [data.revision, data.revision2])
+        assert actual_result == {'revision:add': 1}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('revision', self.revision),
-                          ('revision', self.revision2)])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('revision', data.revision),
+                ('revision', data.revision2)]
+
+    def test_revision_add_name_clash(self, swh_storage):
+        revision1 = data.revision
+        revision2 = data.revision2
 
-    def test_revision_add_name_clash(self):
-        revision1 = self.revision.copy()
-        revision2 = self.revision2.copy()
         revision1['author'] = {
             'fullname': b'John Doe <john.doe@example.com>',
             'name': b'John Doe',
             'email': b'john.doe@example.com'
         }
         revision2['author'] = {
             'fullname': b'John Doe <john.doe@example.com>',
             'name': b'John Doe ',
             'email': b'john.doe@example.com '
         }
-        actual_result = self.storage.revision_add([revision1, revision2])
-        self.assertEqual(actual_result, {'revision:add': 2})
+        actual_result = swh_storage.revision_add([revision1, revision2])
+        assert actual_result == {'revision:add': 2}
 
-    def test_revision_log(self):
+    def test_revision_log(self, swh_storage):
         # given
-        # self.revision4 -is-child-of-> self.revision3
-        self.storage.revision_add([self.revision3,
-                                   self.revision4])
+        # data.revision4 -is-child-of-> data.revision3
+        swh_storage.revision_add([data.revision3,
+                                  data.revision4])
 
         # when
-        actual_results = list(self.storage.revision_log(
-            [self.revision4['id']]))
+        actual_results = list(swh_storage.revision_log(
+            [data.revision4['id']]))
 
         # hack: ids generated
         for actual_result in actual_results:
             if 'id' in actual_result['author']:
                 del actual_result['author']['id']
             if 'id' in actual_result['committer']:
                 del actual_result['committer']['id']
 
-        self.assertEqual(len(actual_results), 2)  # rev4 -child-> rev3
-        self.assertEqual(actual_results[0],
-                         self.normalize_entity(self.revision4))
-        self.assertEqual(actual_results[1],
-                         self.normalize_entity(self.revision3))
+        assert len(actual_results) == 2  # rev4 -child-> rev3
+        assert actual_results[0] == normalize_entity(data.revision4)
+        assert actual_results[1] == normalize_entity(data.revision3)
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('revision', self.revision3),
-                          ('revision', self.revision4)])
+        assert list(swh_storage.journal_writer.objects) == [
+            ('revision', data.revision3),
+            ('revision', data.revision4)]
 
-    def test_revision_log_with_limit(self):
+    def test_revision_log_with_limit(self, swh_storage):
         # given
-        # self.revision4 -is-child-of-> self.revision3
-        self.storage.revision_add([self.revision3,
-                                   self.revision4])
-        actual_results = list(self.storage.revision_log(
-            [self.revision4['id']], 1))
+        # data.revision4 -is-child-of-> data.revision3
+        swh_storage.revision_add([data.revision3,
+                                  data.revision4])
+        actual_results = list(swh_storage.revision_log(
+            [data.revision4['id']], 1))
 
         # hack: ids generated
         for actual_result in actual_results:
             if 'id' in actual_result['author']:
                 del actual_result['author']['id']
             if 'id' in actual_result['committer']:
                 del actual_result['committer']['id']
 
-        self.assertEqual(len(actual_results), 1)
-        self.assertEqual(actual_results[0], self.revision4)
-
-    def test_revision_log_unknown_revision(self):
-        rev_log = list(self.storage.revision_log([self.revision['id']]))
-        self.assertEqual(rev_log, [])
+        assert len(actual_results) == 1
+        assert actual_results[0] == data.revision4
 
-    @staticmethod
-    def _short_revision(revision):
-        return [revision['id'], revision['parents']]
+    def test_revision_log_unknown_revision(self, swh_storage):
+        rev_log = list(swh_storage.revision_log([data.revision['id']]))
+        assert rev_log == []
 
-    def test_revision_shortlog(self):
+    def test_revision_shortlog(self, swh_storage):
         # given
-        # self.revision4 -is-child-of-> self.revision3
-        self.storage.revision_add([self.revision3,
-                                   self.revision4])
+        # data.revision4 -is-child-of-> data.revision3
+        swh_storage.revision_add([data.revision3,
+                                  data.revision4])
 
         # when
-        actual_results = list(self.storage.revision_shortlog(
-            [self.revision4['id']]))
+        actual_results = list(swh_storage.revision_shortlog(
+            [data.revision4['id']]))
 
-        self.assertEqual(len(actual_results), 2)  # rev4 -child-> rev3
-        self.assertEqual(list(actual_results[0]),
-                         self._short_revision(self.revision4))
-        self.assertEqual(list(actual_results[1]),
-                         self._short_revision(self.revision3))
+        assert len(actual_results) == 2  # rev4 -child-> rev3
+        assert list(actual_results[0]) == short_revision(data.revision4)
+        assert list(actual_results[1]) == short_revision(data.revision3)
 
-    def test_revision_shortlog_with_limit(self):
+    def test_revision_shortlog_with_limit(self, swh_storage):
         # given
-        # self.revision4 -is-child-of-> self.revision3
-        self.storage.revision_add([self.revision3,
-                                   self.revision4])
-        actual_results = list(self.storage.revision_shortlog(
-            [self.revision4['id']], 1))
+        # data.revision4 -is-child-of-> data.revision3
+        swh_storage.revision_add([data.revision3,
+                                  data.revision4])
+        actual_results = list(swh_storage.revision_shortlog(
+            [data.revision4['id']], 1))
 
-        self.assertEqual(len(actual_results), 1)
-        self.assertEqual(list(actual_results[0]),
-                         self._short_revision(self.revision4))
+        assert len(actual_results) == 1
+        assert list(actual_results[0]) == short_revision(data.revision4)
 
-    def test_revision_get(self):
-        self.storage.revision_add([self.revision])
+    def test_revision_get(self, swh_storage):
+        swh_storage.revision_add([data.revision])
 
-        actual_revisions = list(self.storage.revision_get(
-            [self.revision['id'], self.revision2['id']]))
+        actual_revisions = list(swh_storage.revision_get(
+            [data.revision['id'], data.revision2['id']]))
 
         # when
         if 'id' in actual_revisions[0]['author']:
             del actual_revisions[0]['author']['id']  # hack: ids are generated
         if 'id' in actual_revisions[0]['committer']:
             del actual_revisions[0]['committer']['id']
 
-        self.assertEqual(len(actual_revisions), 2)
-        self.assertEqual(actual_revisions[0],
-                         self.normalize_entity(self.revision))
-        self.assertIsNone(actual_revisions[1])
+        assert len(actual_revisions) == 2
+        assert actual_revisions[0] == normalize_entity(data.revision)
+        assert actual_revisions[1] is None
+
+    def test_revision_get_no_parents(self, swh_storage):
+        swh_storage.revision_add([data.revision3])
+
+        get = list(swh_storage.revision_get([data.revision3['id']]))
 
-    def test_revision_get_no_parents(self):
-        self.storage.revision_add([self.revision3])
+        assert len(get) == 1
+        assert get[0]['parents'] == []  # no parents on this one
 
-        get = list(self.storage.revision_get([self.revision3['id']]))
+    def test_release_add(self, swh_storage):
+        init_missing = swh_storage.release_missing([data.release['id'],
+                                                    data.release2['id']])
+        assert [data.release['id'], data.release2['id']] == list(init_missing)
 
-        self.assertEqual(len(get), 1)
-        self.assertEqual(get[0]['parents'], [])  # no parents on this one
+        actual_result = swh_storage.release_add([data.release, data.release2])
+        assert actual_result == {'release:add': 2}
 
-    def test_release_add(self):
-        init_missing = self.storage.release_missing([self.release['id'],
-                                                     self.release2['id']])
-        self.assertEqual([self.release['id'], self.release2['id']],
-                         list(init_missing))
+        end_missing = swh_storage.release_missing([data.release['id'],
+                                                   data.release2['id']])
+        assert list(end_missing) == []
 
-        actual_result = self.storage.release_add([self.release, self.release2])
-        self.assertEqual(actual_result, {'release:add': 2})
+        assert list(swh_storage.journal_writer.objects) == [
+            ('release', data.release),
+            ('release', data.release2)]
 
-        end_missing = self.storage.release_missing([self.release['id'],
-                                                    self.release2['id']])
-        self.assertEqual([], list(end_missing))
+        # already present so nothing added
+        actual_result = swh_storage.release_add([data.release, data.release2])
+        assert actual_result == {'release:add': 0}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('release', self.release),
-                          ('release', self.release2)])
+    def test_release_add_no_author_date(self, swh_storage):
+        release = data.release
 
-    def test_release_add_no_author_date(self):
-        release = self.release.copy()
         release['author'] = None
         release['date'] = None
 
-        actual_result = self.storage.release_add([release])
-        self.assertEqual(actual_result, {'release:add': 1})
+        actual_result = swh_storage.release_add([release])
+        assert actual_result == {'release:add': 1}
 
-        end_missing = self.storage.release_missing([self.release['id']])
-        self.assertEqual([], list(end_missing))
+        end_missing = swh_storage.release_missing([data.release['id']])
+        assert list(end_missing) == []
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('release', release)])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('release', release)]
 
-    def test_release_add_validation(self):
-        rel = copy.deepcopy(self.release)
+    def test_release_add_validation(self, swh_storage):
+        rel = copy.deepcopy(data.release)
         rel['date']['offset'] = 2**16
 
-        with self.assertRaisesRegex(
-                (ValueError, psycopg2.DataError), 'offset') as cm:
-            self.storage.release_add([rel])
+        with pytest.raises((ValueError, psycopg2.DataError),
+                           match='offset') as cm:
+            swh_storage.release_add([rel])
 
-        if type(cm.exception) == psycopg2.DataError:
-            self.assertEqual(cm.exception.pgcode,
-                             psycopg2.errorcodes.NUMERIC_VALUE_OUT_OF_RANGE)
+        if type(cm.value) == psycopg2.DataError:
+            assert cm.value.pgcode \
+                == psycopg2.errorcodes.NUMERIC_VALUE_OUT_OF_RANGE
 
-        rel = copy.deepcopy(self.release)
+        rel = copy.deepcopy(data.release)
         rel['author'] = None
 
-        with self.assertRaisesRegex(
-                (ValueError, psycopg2.IntegrityError), 'date') as cm:
-            self.storage.release_add([rel])
+        with pytest.raises((ValueError, psycopg2.IntegrityError),
+                           match='date') as cm:
+            swh_storage.release_add([rel])
 
-        if type(cm.exception) == psycopg2.IntegrityError:
-            self.assertEqual(cm.exception.pgcode,
-                             psycopg2.errorcodes.CHECK_VIOLATION)
+        if type(cm.value) == psycopg2.IntegrityError:
+            assert cm.value.pgcode == psycopg2.errorcodes.CHECK_VIOLATION
 
-    def test_release_add_twice(self):
-        actual_result = self.storage.release_add([self.release])
-        self.assertEqual(actual_result, {'release:add': 1})
+    def test_release_add_twice(self, swh_storage):
+        actual_result = swh_storage.release_add([data.release])
+        assert actual_result == {'release:add': 1}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('release', self.release)])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('release', data.release)]
 
-        actual_result = self.storage.release_add([self.release, self.release2])
-        self.assertEqual(actual_result, {'release:add': 1})
+        actual_result = swh_storage.release_add([data.release, data.release2])
+        assert actual_result == {'release:add': 1}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('release', self.release),
-                          ('release', self.release2)])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('release', data.release),
+                ('release', data.release2)]
+
+    def test_release_add_name_clash(self, swh_storage):
+        release1 = data.release.copy()
+        release2 = data.release2.copy()
 
-    def test_release_add_name_clash(self):
-        release1 = self.release.copy()
-        release2 = self.release2.copy()
         release1['author'] = {
             'fullname': b'John Doe <john.doe@example.com>',
             'name': b'John Doe',
             'email': b'john.doe@example.com'
         }
         release2['author'] = {
             'fullname': b'John Doe <john.doe@example.com>',
             'name': b'John Doe ',
             'email': b'john.doe@example.com '
         }
-        actual_result = self.storage.release_add([release1, release2])
-        self.assertEqual(actual_result, {'release:add': 2})
+        actual_result = swh_storage.release_add([release1, release2])
+        assert actual_result == {'release:add': 2}
 
-    def test_release_get(self):
+    def test_release_get(self, swh_storage):
         # given
-        self.storage.release_add([self.release, self.release2])
+        swh_storage.release_add([data.release, data.release2])
 
         # when
-        actual_releases = list(self.storage.release_get([self.release['id'],
-                                                         self.release2['id']]))
+        actual_releases = list(swh_storage.release_get([data.release['id'],
+                                                        data.release2['id']]))
 
         # then
         for actual_release in actual_releases:
             if 'id' in actual_release['author']:
                 del actual_release['author']['id']  # hack: ids are generated
 
-        self.assertEqual([self.normalize_entity(self.release),
-                          self.normalize_entity(self.release2)],
-                         [actual_releases[0], actual_releases[1]])
+        assert [
+            normalize_entity(data.release), normalize_entity(data.release2)] \
+            == [actual_releases[0], actual_releases[1]]
 
         unknown_releases = \
-            list(self.storage.release_get([self.release3['id']]))
+            list(swh_storage.release_get([data.release3['id']]))
 
-        self.assertIsNone(unknown_releases[0])
+        assert unknown_releases[0] is None
 
-    def test_origin_add_one(self):
-        origin0 = self.storage.origin_get(self.origin)
-        self.assertIsNone(origin0)
+    def test_origin_add_one(self, swh_storage):
+        origin0 = swh_storage.origin_get(data.origin)
+        assert origin0 is None
 
-        id = self.storage.origin_add_one(self.origin)
+        id = swh_storage.origin_add_one(data.origin)
 
-        actual_origin = self.storage.origin_get({'url': self.origin['url']})
+        actual_origin = swh_storage.origin_get({'url': data.origin['url']})
         if self._test_origin_ids:
-            self.assertEqual(actual_origin['id'], id)
-        self.assertEqual(actual_origin['url'], self.origin['url'])
+            assert actual_origin['id'] == id
+        assert actual_origin['url'] == data.origin['url']
 
-        id2 = self.storage.origin_add_one(self.origin)
+        id2 = swh_storage.origin_add_one(data.origin)
 
-        self.assertEqual(id, id2)
+        assert id == id2
 
-    def test_origin_add(self):
-        origin0 = self.storage.origin_get([self.origin])[0]
-        self.assertIsNone(origin0)
+    def test_origin_add(self, swh_storage):
+        origin0 = swh_storage.origin_get([data.origin])[0]
+        assert origin0 is None
 
-        origin1, origin2 = self.storage.origin_add([self.origin, self.origin2])
+        origin1, origin2 = swh_storage.origin_add([data.origin, data.origin2])
 
-        actual_origin = self.storage.origin_get([{
-            'url': self.origin['url'],
+        actual_origin = swh_storage.origin_get([{
+            'url': data.origin['url'],
         }])[0]
         if self._test_origin_ids:
-            self.assertEqual(actual_origin['id'], origin1['id'])
-        self.assertEqual(actual_origin['url'], origin1['url'])
+            assert actual_origin['id'] == origin1['id']
+        assert actual_origin['url'] == origin1['url']
 
-        actual_origin2 = self.storage.origin_get([{
-            'url': self.origin2['url'],
+        actual_origin2 = swh_storage.origin_get([{
+            'url': data.origin2['url'],
         }])[0]
         if self._test_origin_ids:
-            self.assertEqual(actual_origin2['id'], origin2['id'])
-        self.assertEqual(actual_origin2['url'], origin2['url'])
+            assert actual_origin2['id'] == origin2['id']
+        assert actual_origin2['url'] == origin2['url']
 
         if 'id' in actual_origin:
             del actual_origin['id']
             del actual_origin2['id']
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('origin', actual_origin),
-                          ('origin', actual_origin2)])
-
-    def test_origin_add_twice(self):
-        add1 = self.storage.origin_add([self.origin, self.origin2])
-
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('origin', self.origin),
-                          ('origin', self.origin2)])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('origin', actual_origin),
+                ('origin', actual_origin2)]
 
-        add2 = self.storage.origin_add([self.origin, self.origin2])
+    def test_origin_add_twice(self, swh_storage):
+        add1 = swh_storage.origin_add([data.origin, data.origin2])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('origin', data.origin),
+                ('origin', data.origin2)]
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('origin', self.origin),
-                          ('origin', self.origin2)])
+        add2 = swh_storage.origin_add([data.origin, data.origin2])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('origin', data.origin),
+                ('origin', data.origin2)]
 
-        self.assertEqual(add1, add2)
+        assert add1 == add2
 
-    def test_origin_add_validation(self):
-        with self.assertRaisesRegex((TypeError, KeyError), 'url'):
-            self.storage.origin_add([{'type': 'git'}])
+    def test_origin_add_validation(self, swh_storage):
+        with pytest.raises((TypeError, KeyError), match='url'):
+            swh_storage.origin_add([{'type': 'git'}])
 
-    def test_origin_get_legacy(self):
-        self.assertIsNone(self.storage.origin_get(self.origin))
-        id = self.storage.origin_add_one(self.origin)
+    def test_origin_get_legacy(self, swh_storage):
+        assert swh_storage.origin_get(data.origin) is None
+        id = swh_storage.origin_add_one(data.origin)
 
         # lookup per url (returns id)
-        actual_origin0 = self.storage.origin_get(
-            {'url': self.origin['url']})
+        actual_origin0 = swh_storage.origin_get(
+            {'url': data.origin['url']})
         if self._test_origin_ids:
-            self.assertEqual(actual_origin0['id'], id)
-        self.assertEqual(actual_origin0['url'], self.origin['url'])
+            assert actual_origin0['id'] == id
+        assert actual_origin0['url'] == data.origin['url']
 
         # lookup per id (returns dict)
         if self._test_origin_ids:
-            actual_origin1 = self.storage.origin_get({'id': id})
+            actual_origin1 = swh_storage.origin_get({'id': id})
 
-            self.assertEqual(actual_origin1, {'id': id,
-                                              'type': self.origin['type'],
-                                              'url': self.origin['url']})
+            assert actual_origin1 == {'id': id,
+                                      'type': data.origin['type'],
+                                      'url': data.origin['url']}
 
-    def test_origin_get(self):
-        self.assertIsNone(self.storage.origin_get(self.origin))
-        origin_id = self.storage.origin_add_one(self.origin)
+    def test_origin_get(self, swh_storage):
+        assert swh_storage.origin_get(data.origin) is None
+        origin_id = swh_storage.origin_add_one(data.origin)
 
         # lookup per url (returns id)
-        actual_origin0 = self.storage.origin_get(
-            [{'url': self.origin['url']}])
-        self.assertEqual(len(actual_origin0), 1, actual_origin0)
-        if self._test_origin_ids:
-            self.assertEqual(actual_origin0[0]['id'], origin_id)
-        self.assertEqual(actual_origin0[0]['url'], self.origin['url'])
+        actual_origin0 = swh_storage.origin_get(
+            [{'url': data.origin['url']}])
+        assert len(actual_origin0) == 1
+        assert actual_origin0[0]['url'] == data.origin['url']
 
         if self._test_origin_ids:
             # lookup per id (returns dict)
-            actual_origin1 = self.storage.origin_get([{'id': origin_id}])
+            actual_origin1 = swh_storage.origin_get([{'id': origin_id}])
 
-            self.assertEqual(len(actual_origin1), 1, actual_origin1)
-            self.assertEqual(actual_origin1[0], {'id': origin_id,
-                                                 'type': self.origin['type'],
-                                                 'url': self.origin['url']})
+            assert len(actual_origin1) == 1
+            assert actual_origin1[0] == {'id': origin_id,
+                                         'type': data.origin['type'],
+                                         'url': data.origin['url']}
 
-    def test_origin_get_consistency(self):
-        self.assertIsNone(self.storage.origin_get(self.origin))
-        id = self.storage.origin_add_one(self.origin)
+    def test_origin_get_consistency(self, swh_storage):
+        assert swh_storage.origin_get(data.origin) is None
+        id = swh_storage.origin_add_one(data.origin)
 
-        with self.assertRaises(ValueError):
-            self.storage.origin_get([
-                {'url': self.origin['url']},
+        with pytest.raises(ValueError):
+            swh_storage.origin_get([
+                {'url': data.origin['url']},
                 {'id': id}])
 
-    def test_origin_search_single_result(self):
-        found_origins = list(self.storage.origin_search(self.origin['url']))
-        self.assertEqual(len(found_origins), 0)
+    def test_origin_search_single_result(self, swh_storage):
+        found_origins = list(swh_storage.origin_search(data.origin['url']))
+        assert len(found_origins) == 0
 
-        found_origins = list(self.storage.origin_search(self.origin['url'],
-                                                        regexp=True))
-        self.assertEqual(len(found_origins), 0)
+        found_origins = list(swh_storage.origin_search(data.origin['url'],
+                                                       regexp=True))
+        assert len(found_origins) == 0
 
-        self.storage.origin_add_one(self.origin)
+        swh_storage.origin_add_one(data.origin)
         origin_data = {
-            'type': self.origin['type'],
-            'url': self.origin['url']}
-        found_origins = list(self.storage.origin_search(self.origin['url']))
-        self.assertEqual(len(found_origins), 1)
+            'type': data.origin['type'],
+            'url': data.origin['url']}
+        found_origins = list(swh_storage.origin_search(data.origin['url']))
+        assert len(found_origins) == 1
         if 'id' in found_origins[0]:
             del found_origins[0]['id']
-        self.assertEqual(found_origins[0], origin_data)
+        assert found_origins[0] == origin_data
 
-        found_origins = list(self.storage.origin_search(
-            '.' + self.origin['url'][1:-1] + '.', regexp=True))
-        self.assertEqual(len(found_origins), 1)
+        found_origins = list(swh_storage.origin_search(
+            '.' + data.origin['url'][1:-1] + '.', regexp=True))
+        assert len(found_origins) == 1
         if 'id' in found_origins[0]:
             del found_origins[0]['id']
-        self.assertEqual(found_origins[0], origin_data)
+        assert found_origins[0] == origin_data
 
-        self.storage.origin_add_one(self.origin2)
+        swh_storage.origin_add_one(data.origin2)
         origin2_data = {
-            'type': self.origin2['type'],
-            'url': self.origin2['url']}
-        found_origins = list(self.storage.origin_search(self.origin2['url']))
-        self.assertEqual(len(found_origins), 1)
+            'type': data.origin2['type'],
+            'url': data.origin2['url']}
+        found_origins = list(swh_storage.origin_search(data.origin2['url']))
+        assert len(found_origins) == 1
         if 'id' in found_origins[0]:
             del found_origins[0]['id']
-        self.assertEqual(found_origins[0], origin2_data)
+        assert found_origins[0] == origin2_data
 
-        found_origins = list(self.storage.origin_search(
-            '.' + self.origin2['url'][1:-1] + '.', regexp=True))
-        self.assertEqual(len(found_origins), 1)
+        found_origins = list(swh_storage.origin_search(
+            '.' + data.origin2['url'][1:-1] + '.', regexp=True))
+        assert len(found_origins) == 1
         if 'id' in found_origins[0]:
             del found_origins[0]['id']
-        self.assertEqual(found_origins[0], origin2_data)
+        assert found_origins[0] == origin2_data
 
-    def test_origin_search_no_regexp(self):
-        self.storage.origin_add_one(self.origin)
-        self.storage.origin_add_one(self.origin2)
+    def test_origin_search_no_regexp(self, swh_storage):
+        swh_storage.origin_add_one(data.origin)
+        swh_storage.origin_add_one(data.origin2)
 
-        origin = self.storage.origin_get({'url': self.origin['url']})
-        origin2 = self.storage.origin_get({'url': self.origin2['url']})
+        origin = swh_storage.origin_get({'url': data.origin['url']})
+        origin2 = swh_storage.origin_get({'url': data.origin2['url']})
 
         # no pagination
-
-        found_origins = list(self.storage.origin_search('/'))
-        self.assertEqual(len(found_origins), 2)
+        found_origins = list(swh_storage.origin_search('/'))
+        assert len(found_origins) == 2
 
         # offset=0
-
-        found_origins0 = list(self.storage.origin_search('/', offset=0, limit=1)) # noqa
-        self.assertEqual(len(found_origins0), 1)
-        self.assertIn(found_origins0[0], [origin, origin2])
+        found_origins0 = list(swh_storage.origin_search('/', offset=0, limit=1)) # noqa
+        assert len(found_origins0) == 1
+        assert found_origins0[0] in [origin, origin2]
 
         # offset=1
-
-        found_origins1 = list(self.storage.origin_search('/', offset=1, limit=1)) # noqa
-        self.assertEqual(len(found_origins1), 1)
-        self.assertIn(found_origins1[0], [origin, origin2])
+        found_origins1 = list(swh_storage.origin_search('/', offset=1, limit=1)) # noqa
+        assert len(found_origins1) == 1
+        assert found_origins1[0] in [origin, origin2]
 
         # check both origins were returned
+        assert found_origins0 != found_origins1
 
-        self.assertCountEqual(found_origins0 + found_origins1,
-                              [origin, origin2])
+    def test_origin_search_regexp_substring(self, swh_storage):
+        swh_storage.origin_add_one(data.origin)
+        swh_storage.origin_add_one(data.origin2)
 
-    def test_origin_search_regexp_substring(self):
-        self.storage.origin_add_one(self.origin)
-        self.storage.origin_add_one(self.origin2)
-
-        origin = self.storage.origin_get({'url': self.origin['url']})
-        origin2 = self.storage.origin_get({'url': self.origin2['url']})
+        origin = swh_storage.origin_get({'url': data.origin['url']})
+        origin2 = swh_storage.origin_get({'url': data.origin2['url']})
 
         # no pagination
-
-        found_origins = list(self.storage.origin_search('/', regexp=True))
-        self.assertEqual(len(found_origins), 2)
+        found_origins = list(swh_storage.origin_search('/', regexp=True))
+        assert len(found_origins) == 2
 
         # offset=0
-
-        found_origins0 = list(self.storage.origin_search('/', offset=0, limit=1, regexp=True)) # noqa
-        self.assertEqual(len(found_origins0), 1)
-        self.assertIn(found_origins0[0], [origin, origin2])
+        found_origins0 = list(swh_storage.origin_search('/', offset=0, limit=1, regexp=True)) # noqa
+        assert len(found_origins0) == 1
+        assert found_origins0[0] in [origin, origin2]
 
         # offset=1
-
-        found_origins1 = list(self.storage.origin_search('/', offset=1, limit=1, regexp=True)) # noqa
-        self.assertEqual(len(found_origins1), 1)
-        self.assertIn(found_origins1[0], [origin, origin2])
+        found_origins1 = list(swh_storage.origin_search('/', offset=1, limit=1, regexp=True)) # noqa
+        assert len(found_origins1) == 1
+        assert found_origins1[0] in [origin, origin2]
 
         # check both origins were returned
+        assert found_origins0 != found_origins1
 
-        self.assertCountEqual(found_origins0 + found_origins1,
-                              [origin, origin2])
+    def test_origin_search_regexp_fullstring(self, swh_storage):
+        swh_storage.origin_add_one(data.origin)
+        swh_storage.origin_add_one(data.origin2)
 
-    def test_origin_search_regexp_fullstring(self):
-        self.storage.origin_add_one(self.origin)
-        self.storage.origin_add_one(self.origin2)
-
-        origin = self.storage.origin_get({'url': self.origin['url']})
-        origin2 = self.storage.origin_get({'url': self.origin2['url']})
+        origin = swh_storage.origin_get({'url': data.origin['url']})
+        origin2 = swh_storage.origin_get({'url': data.origin2['url']})
 
         # no pagination
-
-        found_origins = list(self.storage.origin_search('.*/.*', regexp=True))
-        self.assertEqual(len(found_origins), 2)
+        found_origins = list(swh_storage.origin_search('.*/.*', regexp=True))
+        assert len(found_origins) == 2
 
         # offset=0
-
-        found_origins0 = list(self.storage.origin_search('.*/.*', offset=0, limit=1, regexp=True)) # noqa
-        self.assertEqual(len(found_origins0), 1)
-        self.assertIn(found_origins0[0], [origin, origin2])
+        found_origins0 = list(swh_storage.origin_search('.*/.*', offset=0, limit=1, regexp=True)) # noqa
+        assert len(found_origins0) == 1
+        assert found_origins0[0] in [origin, origin2]
 
         # offset=1
-
-        found_origins1 = list(self.storage.origin_search('.*/.*', offset=1, limit=1, regexp=True)) # noqa
-        self.assertEqual(len(found_origins1), 1)
-        self.assertIn(found_origins1[0], [origin, origin2])
+        found_origins1 = list(swh_storage.origin_search('.*/.*', offset=1, limit=1, regexp=True)) # noqa
+        assert len(found_origins1) == 1
+        assert found_origins1[0] in [origin, origin2]
 
         # check both origins were returned
+        assert found_origins0 != found_origins1
 
-        self.assertCountEqual(
-            found_origins0 + found_origins1,
-            [origin, origin2])
-
-    @given(strategies.booleans())
-    def test_origin_visit_add(self, use_url):
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_origin_visit_add(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
-
         # given
-        self.assertIsNone(self.storage.origin_get([self.origin2])[0])
+        origin_id = swh_storage.origin_add_one(data.origin2)
+        assert origin_id is not None
 
-        origin_id = self.storage.origin_add_one(self.origin2)
-        self.assertIsNotNone(origin_id)
-
-        origin_id_or_url = self.origin2['url'] if use_url else origin_id
+        origin_id_or_url = data.origin2['url'] if use_url else origin_id
 
         # when
-        origin_visit1 = self.storage.origin_visit_add(
+        date_visit = datetime.datetime.now(datetime.timezone.utc)
+        origin_visit1 = swh_storage.origin_visit_add(
             origin_id_or_url,
             type='git',
-            date=self.date_visit2)
+            date=date_visit)
 
-        actual_origin_visits = list(self.storage.origin_visit_get(
+        actual_origin_visits = list(swh_storage.origin_visit_get(
             origin_id_or_url))
-        self.assertEqual(actual_origin_visits,
-                         [{
-                             'origin': origin_id,
-                             'date': self.date_visit2,
-                             'visit': origin_visit1['visit'],
-                             'type': 'git',
-                             'status': 'ongoing',
-                             'metadata': None,
-                             'snapshot': None,
-                         }])
-
-        expected_origin = self.origin2.copy()
-        data = {
+        assert {
+                'origin': origin_id,
+                'date': date_visit,
+                'visit': origin_visit1['visit'],
+                'type': 'git',
+                'status': 'ongoing',
+                'metadata': None,
+                'snapshot': None,
+            } in actual_origin_visits
+
+        expected_origin = data.origin2
+        origin_visit = {
             'origin': expected_origin,
-            'date': self.date_visit2,
+            'date': date_visit,
             'visit': origin_visit1['visit'],
             'type': 'git',
             'status': 'ongoing',
             'metadata': None,
             'snapshot': None,
         }
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('origin', expected_origin),
-                          ('origin_visit', data)])
+        objects = list(swh_storage.journal_writer.objects)
+        assert ('origin', expected_origin) in objects
+        assert ('origin_visit', origin_visit) in objects
 
-    def test_origin_visit_get__unknown_origin(self):
-        self.assertEqual([], list(self.storage.origin_visit_get('foo')))
+    def test_origin_visit_get__unknown_origin(self, swh_storage):
+        assert [] == list(swh_storage.origin_visit_get('foo'))
         if self._test_origin_ids:
-            self.assertEqual([], list(self.storage.origin_visit_get(10)))
+            assert list(swh_storage.origin_visit_get(10)) == []
 
-    @given(strategies.booleans())
-    def test_origin_visit_add_default_type(self, use_url):
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_origin_visit_add_default_type(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
-
         # given
-        self.assertIsNone(self.storage.origin_get([self.origin2])[0])
-
-        origin_id = self.storage.origin_add_one(self.origin2)
-        origin_id_or_url = self.origin2['url'] if use_url else origin_id
-        self.assertIsNotNone(origin_id)
+        origin_id = swh_storage.origin_add_one(data.origin2)
+        origin_id_or_url = data.origin2['url'] if use_url else origin_id
+        assert origin_id is not None
 
         # when
-        origin_visit1 = self.storage.origin_visit_add(
+        date_visit = datetime.datetime.now(datetime.timezone.utc)
+        date_visit2 = date_visit + datetime.timedelta(minutes=1)
+        origin_visit1 = swh_storage.origin_visit_add(
             origin_id_or_url,
-            date=self.date_visit2)
-        origin_visit2 = self.storage.origin_visit_add(
+            date=date_visit)
+        origin_visit2 = swh_storage.origin_visit_add(
             origin_id_or_url,
-            date='2018-01-01 23:00:00+00')
+            date=date_visit2)
 
         # then
-        self.assertEqual(origin_visit1['origin'], origin_id)
-        self.assertIsNotNone(origin_visit1['visit'])
+        assert origin_visit1['origin'] == origin_id
+        assert origin_visit1['visit'] is not None
 
-        actual_origin_visits = list(self.storage.origin_visit_get(
+        actual_origin_visits = list(swh_storage.origin_visit_get(
             origin_id_or_url))
-        self.assertEqual(actual_origin_visits, [
-            {
-                'origin': origin_id,
-                'date': self.date_visit2,
-                'visit': origin_visit1['visit'],
-                'type': 'hg',
-                'status': 'ongoing',
-                'metadata': None,
-                'snapshot': None,
-            },
-            {
-                'origin': origin_id,
-                'date': self.date_visit3,
-                'visit': origin_visit2['visit'],
-                'type': 'hg',
-                'status': 'ongoing',
-                'metadata': None,
-                'snapshot': None,
-            },
-        ])
+        expected_visits = [
+                {
+                    'origin': origin_id,
+                    'date': date_visit,
+                    'visit': origin_visit1['visit'],
+                    'type': 'hg',
+                    'status': 'ongoing',
+                    'metadata': None,
+                    'snapshot': None,
+                },
+                {
+                    'origin': origin_id,
+                    'date': date_visit2,
+                    'visit': origin_visit2['visit'],
+                    'type': 'hg',
+                    'status': 'ongoing',
+                    'metadata': None,
+                    'snapshot': None,
+                },
+            ]
+        for visit in expected_visits:
+            assert visit in actual_origin_visits
 
-        expected_origin = self.origin2.copy()
-        data1 = {
-            'origin': expected_origin,
-            'date': self.date_visit2,
-            'visit': origin_visit1['visit'],
-            'type': 'hg',
-            'status': 'ongoing',
-            'metadata': None,
-            'snapshot': None,
-        }
-        data2 = {
-            'origin': expected_origin,
-            'date': self.date_visit3,
-            'visit': origin_visit2['visit'],
-            'type': 'hg',
-            'status': 'ongoing',
-            'metadata': None,
-            'snapshot': None,
-        }
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('origin', expected_origin),
-                          ('origin_visit', data1),
-                          ('origin_visit', data2)])
+        objects = list(swh_storage.journal_writer.objects)
+        assert ('origin', data.origin2) in objects
+
+        for visit in expected_visits:
+            visit['origin'] = data.origin2
+            assert ('origin_visit', visit) in objects
 
-    def test_origin_visit_add_validation(self):
-        origin_id_or_url = self.storage.origin_add_one(self.origin2)
+    def test_origin_visit_add_validation(self, swh_storage):
+        origin_id_or_url = swh_storage.origin_add_one(data.origin2)
 
-        with self.assertRaises((TypeError, psycopg2.ProgrammingError)) as cm:
-            self.storage.origin_visit_add(origin_id_or_url, date=[b'foo'])
+        with pytest.raises((TypeError, psycopg2.ProgrammingError)) as cm:
+            swh_storage.origin_visit_add(origin_id_or_url, date=[b'foo'])
 
-        if type(cm.exception) == psycopg2.ProgrammingError:
-            self.assertEqual(cm.exception.pgcode,
-                             psycopg2.errorcodes.UNDEFINED_FUNCTION)
+        if type(cm.value) == psycopg2.ProgrammingError:
+            assert cm.value.pgcode \
+                == psycopg2.errorcodes.UNDEFINED_FUNCTION
 
-    @given(strategies.booleans())
-    def test_origin_visit_update(self, use_url):
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_origin_visit_update(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
-
         # given
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_id2 = self.storage.origin_add_one(self.origin2)
-        origin2_id_or_url = self.origin2['url'] if use_url else origin_id2
+        swh_storage.origin_add_one(data.origin)
+        origin_url = data.origin['url']
 
-        origin_id_or_url = self.origin['url'] if use_url else origin_id
+        date_visit = datetime.datetime.now(datetime.timezone.utc)
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_url,
+            date=date_visit)
 
-        origin_visit1 = self.storage.origin_visit_add(
-            origin_id_or_url,
-            date=self.date_visit2)
+        date_visit2 = date_visit + datetime.timedelta(minutes=1)
+        origin_visit2 = swh_storage.origin_visit_add(
+            origin_url,
+            date=date_visit2)
 
-        origin_visit2 = self.storage.origin_visit_add(
-            origin_id_or_url,
-            date=self.date_visit3)
-
-        origin_visit3 = self.storage.origin_visit_add(
-            origin2_id_or_url,
-            date=self.date_visit3)
+        swh_storage.origin_add_one(data.origin2)
+        origin_url2 = data.origin2['url']
+        origin_visit3 = swh_storage.origin_visit_add(
+            origin_url2,
+            date=date_visit2)
 
         # when
         visit1_metadata = {
             'contents': 42,
             'directories': 22,
         }
-        self.storage.origin_visit_update(
-            origin_id_or_url,
+        swh_storage.origin_visit_update(
+            origin_url,
             origin_visit1['visit'], status='full',
             metadata=visit1_metadata)
-        self.storage.origin_visit_update(
-            origin2_id_or_url,
+        swh_storage.origin_visit_update(
+            origin_url2,
             origin_visit3['visit'], status='partial')
 
         # then
-        actual_origin_visits = list(self.storage.origin_visit_get(
-            origin_id_or_url))
-        self.assertEqual(actual_origin_visits, [{
+        actual_origin_visits = list(swh_storage.origin_visit_get(
+            origin_url))
+        expected_visits = [{
             'origin': origin_visit2['origin'],
-            'date': self.date_visit2,
+            'date': date_visit,
             'visit': origin_visit1['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'status': 'full',
             'metadata': visit1_metadata,
             'snapshot': None,
         }, {
             'origin': origin_visit2['origin'],
-            'date': self.date_visit3,
+            'date': date_visit2,
             'visit': origin_visit2['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'status': 'ongoing',
             'metadata': None,
             'snapshot': None,
-        }])
+        }]
+        for visit in expected_visits:
+            assert visit in actual_origin_visits
 
-        actual_origin_visits_bis = list(self.storage.origin_visit_get(
-            origin_id_or_url,
+        actual_origin_visits_bis = list(swh_storage.origin_visit_get(
+            origin_url,
             limit=1))
-        self.assertEqual(actual_origin_visits_bis,
-                         [{
-                             'origin': origin_visit2['origin'],
-                             'date': self.date_visit2,
-                             'visit': origin_visit1['visit'],
-                             'type': self.origin['type'],
-                             'status': 'full',
-                             'metadata': visit1_metadata,
-                             'snapshot': None,
-                         }])
-
-        actual_origin_visits_ter = list(self.storage.origin_visit_get(
-            origin_id_or_url,
+        assert actual_origin_visits_bis == [
+            {
+                'origin': origin_visit2['origin'],
+                'date': date_visit,
+                'visit': origin_visit1['visit'],
+                'type': data.origin['type'],
+                'status': 'full',
+                'metadata': visit1_metadata,
+                'snapshot': None,
+            }]
+
+        actual_origin_visits_ter = list(swh_storage.origin_visit_get(
+            origin_url,
             last_visit=origin_visit1['visit']))
-        self.assertEqual(actual_origin_visits_ter,
-                         [{
-                             'origin': origin_visit2['origin'],
-                             'date': self.date_visit3,
-                             'visit': origin_visit2['visit'],
-                             'type': self.origin['type'],
-                             'status': 'ongoing',
-                             'metadata': None,
-                             'snapshot': None,
-                         }])
-
-        actual_origin_visits2 = list(self.storage.origin_visit_get(
-            origin2_id_or_url))
-        self.assertEqual(actual_origin_visits2,
-                         [{
-                             'origin': origin_visit3['origin'],
-                             'date': self.date_visit3,
-                             'visit': origin_visit3['visit'],
-                             'type': self.origin2['type'],
-                             'status': 'partial',
-                             'metadata': None,
-                             'snapshot': None,
-                         }])
-
-        expected_origin = self.origin.copy()
-        expected_origin2 = self.origin2.copy()
+        assert actual_origin_visits_ter == [
+            {
+                'origin': origin_visit2['origin'],
+                'date': date_visit2,
+                'visit': origin_visit2['visit'],
+                'type': data.origin['type'],
+                'status': 'ongoing',
+                'metadata': None,
+                'snapshot': None,
+            }]
+
+        actual_origin_visits2 = list(swh_storage.origin_visit_get(
+            origin_url2))
+        assert actual_origin_visits2 == [
+            {
+                'origin': origin_visit3['origin'],
+                'date': date_visit2,
+                'visit': origin_visit3['visit'],
+                'type': data.origin2['type'],
+                'status': 'partial',
+                'metadata': None,
+                'snapshot': None,
+            }]
+
+        expected_origin = data.origin.copy()
+        expected_origin2 = data.origin2.copy()
         data1 = {
             'origin': expected_origin,
-            'date': self.date_visit2,
+            'date': date_visit,
             'visit': origin_visit1['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'status': 'ongoing',
             'metadata': None,
             'snapshot': None,
         }
         data2 = {
             'origin': expected_origin,
-            'date': self.date_visit3,
+            'date': date_visit2,
             'visit': origin_visit2['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'status': 'ongoing',
             'metadata': None,
             'snapshot': None,
         }
         data3 = {
             'origin': expected_origin2,
-            'date': self.date_visit3,
+            'date': date_visit2,
             'visit': origin_visit3['visit'],
-            'type': self.origin2['type'],
+            'type': data.origin2['type'],
             'status': 'ongoing',
             'metadata': None,
             'snapshot': None,
         }
         data4 = {
             'origin': expected_origin,
-            'date': self.date_visit2,
+            'date': date_visit,
             'visit': origin_visit1['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'metadata': visit1_metadata,
             'status': 'full',
             'snapshot': None,
         }
         data5 = {
             'origin': expected_origin2,
-            'date': self.date_visit3,
+            'date': date_visit2,
             'visit': origin_visit3['visit'],
-            'type': self.origin2['type'],
+            'type': data.origin2['type'],
             'status': 'partial',
             'metadata': None,
             'snapshot': None,
         }
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('origin', expected_origin),
-                          ('origin', expected_origin2),
-                          ('origin_visit', data1),
-                          ('origin_visit', data2),
-                          ('origin_visit', data3),
-                          ('origin_visit', data4),
-                          ('origin_visit', data5)])
-
-    def test_origin_visit_update_validation(self):
-        origin_id = self.storage.origin_add_one(self.origin)
-        visit = self.storage.origin_visit_add(
+        objects = list(swh_storage.journal_writer.objects)
+        assert ('origin', expected_origin) in objects
+        assert ('origin', expected_origin2) in objects
+        assert ('origin_visit', data1) in objects
+        assert ('origin_visit', data2) in objects
+        assert ('origin_visit', data3) in objects
+        assert ('origin_visit', data4) in objects
+        assert ('origin_visit', data5) in objects
+
+    def test_origin_visit_update_validation(self, swh_storage):
+        origin_id = swh_storage.origin_add_one(data.origin)
+        visit = swh_storage.origin_visit_add(
             origin_id,
-            date=self.date_visit2)
+            date=data.date_visit2)
 
-        with self.assertRaisesRegex(
-                (ValueError, psycopg2.DataError), 'status') as cm:
-            self.storage.origin_visit_update(
+        with pytest.raises((ValueError, psycopg2.DataError),
+                           match='status') as cm:
+            swh_storage.origin_visit_update(
                 origin_id, visit['visit'], status='foobar')
 
-        if type(cm.exception) == psycopg2.DataError:
-            self.assertEqual(cm.exception.pgcode,
-                             psycopg2.errorcodes.INVALID_TEXT_REPRESENTATION)
+        if type(cm.value) == psycopg2.DataError:
+            assert cm.value.pgcode == \
+                psycopg2.errorcodes.INVALID_TEXT_REPRESENTATION
 
-    def test_origin_visit_find_by_date(self):
+    def test_origin_visit_find_by_date(self, swh_storage):
         # given
-        self.storage.origin_add_one(self.origin)
+        swh_storage.origin_add_one(data.origin)
 
-        self.storage.origin_visit_add(
-            self.origin['url'],
-            date=self.date_visit2)
+        swh_storage.origin_visit_add(
+            data.origin['url'],
+            date=data.date_visit2)
 
-        origin_visit2 = self.storage.origin_visit_add(
-            self.origin['url'],
-            date=self.date_visit3)
+        origin_visit2 = swh_storage.origin_visit_add(
+            data.origin['url'],
+            date=data.date_visit3)
 
-        origin_visit3 = self.storage.origin_visit_add(
-            self.origin['url'],
-            date=self.date_visit2)
+        origin_visit3 = swh_storage.origin_visit_add(
+            data.origin['url'],
+            date=data.date_visit2)
 
         # Simple case
-        visit = self.storage.origin_visit_find_by_date(
-            self.origin['url'], self.date_visit3)
-        self.assertEqual(visit['visit'], origin_visit2['visit'])
+        visit = swh_storage.origin_visit_find_by_date(
+            data.origin['url'], data.date_visit3)
+        assert visit['visit'] == origin_visit2['visit']
 
         # There are two visits at the same date, the latest must be returned
-        visit = self.storage.origin_visit_find_by_date(
-            self.origin['url'], self.date_visit2)
-        self.assertEqual(visit['visit'], origin_visit3['visit'])
+        visit = swh_storage.origin_visit_find_by_date(
+            data.origin['url'], data.date_visit2)
+        assert visit['visit'] == origin_visit3['visit']
 
-    def test_origin_visit_find_by_date__unknown_origin(self):
-        self.storage.origin_visit_find_by_date('foo', self.date_visit2)
+    def test_origin_visit_find_by_date__unknown_origin(self, swh_storage):
+        swh_storage.origin_visit_find_by_date('foo', data.date_visit2)
 
-    @settings(deadline=None)
-    @given(strategies.booleans())
-    def test_origin_visit_update_missing_snapshot(self, use_url):
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_origin_visit_update_missing_snapshot(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
-
         # given
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_id_or_url = self.origin['url'] if use_url else origin_id
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_id_or_url = data.origin['url'] if use_url else origin_id
 
-        origin_visit = self.storage.origin_visit_add(
+        origin_visit = swh_storage.origin_visit_add(
             origin_id_or_url,
-            date=self.date_visit1)
+            date=data.date_visit1)
 
         # when
-        self.storage.origin_visit_update(
+        swh_storage.origin_visit_update(
             origin_id_or_url,
             origin_visit['visit'],
-            snapshot=self.snapshot['id'])
+            snapshot=data.snapshot['id'])
 
         # then
-        actual_origin_visit = self.storage.origin_visit_get_by(
+        actual_origin_visit = swh_storage.origin_visit_get_by(
             origin_id_or_url,
             origin_visit['visit'])
-        self.assertEqual(actual_origin_visit['snapshot'], self.snapshot['id'])
+        assert actual_origin_visit['snapshot'] == data.snapshot['id']
 
         # when
-        self.storage.snapshot_add([self.snapshot])
-        self.assertEqual(actual_origin_visit['snapshot'], self.snapshot['id'])
+        swh_storage.snapshot_add([data.snapshot])
+        assert actual_origin_visit['snapshot'] == data.snapshot['id']
 
-    @settings(deadline=None)
-    @given(strategies.booleans())
-    def test_origin_visit_get_by(self, use_url):
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_origin_visit_get_by(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
-
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_id2 = self.storage.origin_add_one(self.origin2)
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_id2 = swh_storage.origin_add_one(data.origin2)
 
-        origin_id_or_url = self.origin['url'] if use_url else origin_id
-        origin2_id_or_url = self.origin2['url'] if use_url else origin_id2
+        origin_id_or_url = data.origin['url'] if use_url else origin_id
+        origin2_id_or_url = data.origin2['url'] if use_url else origin_id2
 
-        origin_visit1 = self.storage.origin_visit_add(
+        origin_visit1 = swh_storage.origin_visit_add(
             origin_id_or_url,
-            date=self.date_visit2)
+            date=data.date_visit2)
 
-        self.storage.snapshot_add([self.snapshot])
-        self.storage.origin_visit_update(
+        swh_storage.snapshot_add([data.snapshot])
+        swh_storage.origin_visit_update(
             origin_id_or_url,
             origin_visit1['visit'],
-            snapshot=self.snapshot['id'])
+            snapshot=data.snapshot['id'])
 
         # Add some other {origin, visit} entries
-        self.storage.origin_visit_add(
+        swh_storage.origin_visit_add(
             origin_id_or_url,
-            date=self.date_visit3)
-        self.storage.origin_visit_add(
+            date=data.date_visit3)
+        swh_storage.origin_visit_add(
             origin2_id_or_url,
-            date=self.date_visit3)
+            date=data.date_visit3)
 
         # when
         visit1_metadata = {
             'contents': 42,
             'directories': 22,
         }
 
-        self.storage.origin_visit_update(
+        swh_storage.origin_visit_update(
             origin_id_or_url,
             origin_visit1['visit'], status='full',
             metadata=visit1_metadata)
 
         expected_origin_visit = origin_visit1.copy()
         expected_origin_visit.update({
             'origin': origin_id,
             'visit': origin_visit1['visit'],
-            'date': self.date_visit2,
-            'type': self.origin['type'],
+            'date': data.date_visit2,
+            'type': data.origin['type'],
             'metadata': visit1_metadata,
             'status': 'full',
-            'snapshot': self.snapshot['id'],
+            'snapshot': data.snapshot['id'],
         })
 
         # when
-        actual_origin_visit1 = self.storage.origin_visit_get_by(
+        actual_origin_visit1 = swh_storage.origin_visit_get_by(
             origin_id_or_url,
             origin_visit1['visit'])
 
         # then
-        self.assertEqual(actual_origin_visit1, expected_origin_visit)
+        assert actual_origin_visit1 == expected_origin_visit
 
-    def test_origin_visit_get_by__unknown_origin(self):
+    def test_origin_visit_get_by__unknown_origin(self, swh_storage):
         if self._test_origin_ids:
-            self.assertIsNone(self.storage.origin_visit_get_by(2, 10))
-        self.assertIsNone(self.storage.origin_visit_get_by('foo', 10))
+            assert swh_storage.origin_visit_get_by(2, 10) is None
+        assert swh_storage.origin_visit_get_by('foo', 10) is None
 
-    @given(strategies.booleans())
-    def test_origin_visit_upsert_new(self, use_url):
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_origin_visit_upsert_new(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
-
         # given
-        self.assertIsNone(self.storage.origin_get([self.origin2])[0])
-
-        origin_id = self.storage.origin_add_one(self.origin2)
-        origin_id_or_url = self.origin2['url'] if use_url else origin_id
-        self.assertIsNotNone(origin_id)
+        origin_id = swh_storage.origin_add_one(data.origin2)
+        origin_url = data.origin2['url']
+        assert origin_id is not None
 
         # when
-        self.storage.origin_visit_upsert([
+        swh_storage.origin_visit_upsert([
             {
-                 'origin': self.origin2,
-                 'date': self.date_visit2,
+                 'origin': data.origin2,
+                 'date': data.date_visit2,
                  'visit': 123,
-                 'type': self.origin2['type'],
+                 'type': data.origin2['type'],
                  'status': 'full',
                  'metadata': None,
                  'snapshot': None,
              },
             {
-                 'origin': self.origin2,
+                 'origin': data.origin2,
                  'date': '2018-01-01 23:00:00+00',
                  'visit': 1234,
-                 'type': self.origin2['type'],
+                 'type': data.origin2['type'],
                  'status': 'full',
                  'metadata': None,
                  'snapshot': None,
              },
         ])
 
         # then
-        actual_origin_visits = list(self.storage.origin_visit_get(
-            origin_id_or_url))
-        self.assertEqual(actual_origin_visits, [
+        actual_origin_visits = list(swh_storage.origin_visit_get(
+            origin_url))
+        assert actual_origin_visits == [
             {
                 'origin': origin_id,
-                'date': self.date_visit2,
+                'date': data.date_visit2,
                 'visit': 123,
-                'type': self.origin2['type'],
+                'type': data.origin2['type'],
                 'status': 'full',
                 'metadata': None,
                 'snapshot': None,
             },
             {
                 'origin': origin_id,
-                'date': self.date_visit3,
+                'date': data.date_visit3,
                 'visit': 1234,
-                'type': self.origin2['type'],
+                'type': data.origin2['type'],
                 'status': 'full',
                 'metadata': None,
                 'snapshot': None,
             },
-        ])
+        ]
 
-        expected_origin = self.origin2.copy()
+        expected_origin = data.origin2
         data1 = {
             'origin': expected_origin,
-            'date': self.date_visit2,
+            'date': data.date_visit2,
             'visit': 123,
-            'type': self.origin2['type'],
+            'type': data.origin2['type'],
             'status': 'full',
             'metadata': None,
             'snapshot': None,
         }
         data2 = {
             'origin': expected_origin,
-            'date': self.date_visit3,
+            'date': data.date_visit3,
             'visit': 1234,
-            'type': self.origin2['type'],
+            'type': data.origin2['type'],
             'status': 'full',
             'metadata': None,
             'snapshot': None,
         }
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('origin', expected_origin),
-                          ('origin_visit', data1),
-                          ('origin_visit', data2)])
-
-    @settings(deadline=None)
-    @given(strategies.booleans())
-    def test_origin_visit_upsert_existing(self, use_url):
+        assert list(swh_storage.journal_writer.objects) == [
+            ('origin', expected_origin),
+            ('origin_visit', data1),
+            ('origin_visit', data2)]
+
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_origin_visit_upsert_existing(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
-
         # given
-        self.assertIsNone(self.storage.origin_get([self.origin2])[0])
-
-        origin_id = self.storage.origin_add_one(self.origin2)
-        origin_id_or_url = self.origin2['url'] if use_url else origin_id
-        self.assertIsNotNone(origin_id)
+        origin_id = swh_storage.origin_add_one(data.origin2)
+        origin_url = data.origin2['url']
+        assert origin_id is not None
 
         # when
-        origin_visit1 = self.storage.origin_visit_add(
-            origin_id_or_url,
-            date=self.date_visit2)
-        self.storage.origin_visit_upsert([{
-             'origin': self.origin2,
-             'date': self.date_visit2,
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_url,
+            date=data.date_visit2)
+        swh_storage.origin_visit_upsert([{
+             'origin': data.origin2,
+             'date': data.date_visit2,
              'visit': origin_visit1['visit'],
-             'type': self.origin2['type'],
+             'type': data.origin2['type'],
              'status': 'full',
              'metadata': None,
              'snapshot': None,
          }])
 
         # then
-        self.assertEqual(origin_visit1['origin'], origin_id)
-        self.assertIsNotNone(origin_visit1['visit'])
+        assert origin_visit1['origin'] == origin_id
+        assert origin_visit1['visit'] is not None
 
-        actual_origin_visits = list(self.storage.origin_visit_get(
-            origin_id_or_url))
-        self.assertEqual(actual_origin_visits,
-                         [{
-                             'origin': origin_id,
-                             'date': self.date_visit2,
-                             'visit': origin_visit1['visit'],
-                             'type': self.origin2['type'],
-                             'status': 'full',
-                             'metadata': None,
-                             'snapshot': None,
-                         }])
-
-        expected_origin = self.origin2.copy()
+        actual_origin_visits = list(swh_storage.origin_visit_get(
+            origin_url))
+        assert actual_origin_visits == [
+            {
+                'origin': origin_id,
+                'date': data.date_visit2,
+                'visit': origin_visit1['visit'],
+                'type': data.origin2['type'],
+                'status': 'full',
+                'metadata': None,
+                'snapshot': None,
+            }]
+
+        expected_origin = data.origin2
         data1 = {
             'origin': expected_origin,
-            'date': self.date_visit2,
+            'date': data.date_visit2,
             'visit': origin_visit1['visit'],
-            'type': self.origin2['type'],
+            'type': data.origin2['type'],
             'status': 'ongoing',
             'metadata': None,
             'snapshot': None,
         }
         data2 = {
             'origin': expected_origin,
-            'date': self.date_visit2,
+            'date': data.date_visit2,
             'visit': origin_visit1['visit'],
-            'type': self.origin2['type'],
+            'type': data.origin2['type'],
             'status': 'full',
             'metadata': None,
             'snapshot': None,
         }
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('origin', expected_origin),
-                          ('origin_visit', data1),
-                          ('origin_visit', data2)])
+        assert list(swh_storage.journal_writer.objects) == [
+            ('origin', expected_origin),
+            ('origin_visit', data1),
+            ('origin_visit', data2)]
 
-    def test_origin_visit_get_by_no_result(self):
+    def test_origin_visit_get_by_no_result(self, swh_storage):
         if self._test_origin_ids:
-            actual_origin_visit = self.storage.origin_visit_get_by(
+            actual_origin_visit = swh_storage.origin_visit_get_by(
                 10, 999)
-            self.assertIsNone(actual_origin_visit)
+            assert actual_origin_visit is None
 
-        self.storage.origin_add([self.origin])
-        actual_origin_visit = self.storage.origin_visit_get_by(
-            self.origin['url'], 999)
-        self.assertIsNone(actual_origin_visit)
+        swh_storage.origin_add([data.origin])
+        actual_origin_visit = swh_storage.origin_visit_get_by(
+            data.origin['url'], 999)
+        assert actual_origin_visit is None
 
-    @settings(deadline=None)  # this test is very slow
-    @given(strategies.booleans())
-    def test_origin_visit_get_latest(self, use_url):
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_origin_visit_get_latest(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
-
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_id_or_url = self.origin['url'] if use_url else origin_id
-        origin_url = self.origin['url']
-        origin_visit1 = self.storage.origin_visit_add(
-            origin_id_or_url,
-            self.date_visit1)
+        swh_storage.origin_add_one(data.origin)
+        origin_url = data.origin['url']
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_url,
+            data.date_visit1)
         visit1_id = origin_visit1['visit']
-        origin_visit2 = self.storage.origin_visit_add(
-            origin_id_or_url,
-            self.date_visit2)
+        origin_visit2 = swh_storage.origin_visit_add(
+            origin_url,
+            data.date_visit2)
         visit2_id = origin_visit2['visit']
 
         # Add a visit with the same date as the previous one
-        origin_visit3 = self.storage.origin_visit_add(
-            origin_id_or_url,
-            self.date_visit2)
+        origin_visit3 = swh_storage.origin_visit_add(
+            origin_url,
+            data.date_visit2)
         visit3_id = origin_visit3['visit']
 
-        origin_visit1 = self.storage.origin_visit_get_by(origin_url, visit1_id)
-        origin_visit2 = self.storage.origin_visit_get_by(origin_url, visit2_id)
-        origin_visit3 = self.storage.origin_visit_get_by(origin_url, visit3_id)
+        origin_visit1 = swh_storage.origin_visit_get_by(origin_url, visit1_id)
+        origin_visit2 = swh_storage.origin_visit_get_by(origin_url, visit2_id)
+        origin_visit3 = swh_storage.origin_visit_get_by(origin_url, visit3_id)
 
         # Two visits, both with no snapshot
-        self.assertEqual(
-            origin_visit3,
-            self.storage.origin_visit_get_latest(origin_url))
-        self.assertIsNone(
-            self.storage.origin_visit_get_latest(origin_url,
-                                                 require_snapshot=True))
+        assert origin_visit3 == swh_storage.origin_visit_get_latest(origin_url)
+        assert swh_storage.origin_visit_get_latest(
+            origin_url, require_snapshot=True) is None
 
         # Add snapshot to visit1; require_snapshot=True makes it return
         # visit1 and require_snapshot=False still returns visit2
-        self.storage.snapshot_add([self.complete_snapshot])
-        self.storage.origin_visit_update(
-            origin_id_or_url, visit1_id,
-            snapshot=self.complete_snapshot['id'])
-        self.assertEqual(
-            {**origin_visit1, 'snapshot': self.complete_snapshot['id']},
-            self.storage.origin_visit_get_latest(
+        swh_storage.snapshot_add([data.complete_snapshot])
+        swh_storage.origin_visit_update(
+            origin_url, visit1_id,
+            snapshot=data.complete_snapshot['id'])
+        assert {**origin_visit1, 'snapshot': data.complete_snapshot['id']} \
+            == swh_storage.origin_visit_get_latest(
                 origin_url, require_snapshot=True)
-        )
-        self.assertEqual(
-            origin_visit3,
-            self.storage.origin_visit_get_latest(origin_url)
-        )
+
+        assert origin_visit3 == swh_storage.origin_visit_get_latest(origin_url)
 
         # Status filter: all three visits are status=ongoing, so no visit
         # returned
-        self.assertIsNone(
-            self.storage.origin_visit_get_latest(
-                origin_url, allowed_statuses=['full'])
-        )
+        assert swh_storage.origin_visit_get_latest(
+                origin_url, allowed_statuses=['full']) is None
 
         # Mark the first visit as completed and check status filter again
-        self.storage.origin_visit_update(
-            origin_id_or_url,
+        swh_storage.origin_visit_update(
+            origin_url,
             visit1_id, status='full')
-        self.assertEqual(
-            {
-                **origin_visit1,
-                'snapshot': self.complete_snapshot['id'],
-                'status': 'full'},
-            self.storage.origin_visit_get_latest(
-                origin_url, allowed_statuses=['full']),
-        )
-        self.assertEqual(
-            origin_visit3,
-            self.storage.origin_visit_get_latest(origin_url),
-        )
+        assert {
+            **origin_visit1,
+            'snapshot': data.complete_snapshot['id'],
+            'status': 'full'} == swh_storage.origin_visit_get_latest(
+                origin_url, allowed_statuses=['full'])
+
+        assert origin_visit3 == swh_storage.origin_visit_get_latest(origin_url)
 
         # Add snapshot to visit2 and check that the new snapshot is returned
-        self.storage.snapshot_add([self.empty_snapshot])
-        self.storage.origin_visit_update(
-            origin_id_or_url, visit2_id,
-            snapshot=self.empty_snapshot['id'])
-        self.assertEqual(
-            {**origin_visit2, 'snapshot': self.empty_snapshot['id']},
-            self.storage.origin_visit_get_latest(
-                origin_url, require_snapshot=True),
-        )
-        self.assertEqual(
-            origin_visit3,
-            self.storage.origin_visit_get_latest(origin_url),
-        )
+        swh_storage.snapshot_add([data.empty_snapshot])
+        swh_storage.origin_visit_update(
+            origin_url, visit2_id,
+            snapshot=data.empty_snapshot['id'])
+        assert {**origin_visit2, 'snapshot': data.empty_snapshot['id']} == \
+            swh_storage.origin_visit_get_latest(
+                origin_url, require_snapshot=True)
+
+        assert origin_visit3 == swh_storage.origin_visit_get_latest(origin_url)
 
         # Check that the status filter is still working
-        self.assertEqual(
-            {
-                **origin_visit1,
-                'snapshot': self.complete_snapshot['id'],
-                'status': 'full'},
-            self.storage.origin_visit_get_latest(
-                origin_url, allowed_statuses=['full']),
-        )
+        assert {
+            **origin_visit1,
+            'snapshot': data.complete_snapshot['id'],
+            'status': 'full'} == swh_storage.origin_visit_get_latest(
+                origin_url, allowed_statuses=['full'])
 
         # Add snapshot to visit3 (same date as visit2)
-        self.storage.snapshot_add([self.complete_snapshot])
-        self.storage.origin_visit_update(
-            origin_id_or_url, visit3_id, snapshot=self.complete_snapshot['id'])
-        self.assertEqual(
-            {
-                **origin_visit1,
-                'snapshot': self.complete_snapshot['id'],
-                'status': 'full'},
-            self.storage.origin_visit_get_latest(
-                origin_url, allowed_statuses=['full']),
-        )
-        self.assertEqual(
-            {
-                **origin_visit1,
-                'snapshot': self.complete_snapshot['id'],
-                'status': 'full'},
-            self.storage.origin_visit_get_latest(
-                origin_url, allowed_statuses=['full'], require_snapshot=True),
-        )
-        self.assertEqual(
-            {**origin_visit3, 'snapshot': self.complete_snapshot['id']},
-            self.storage.origin_visit_get_latest(
-                origin_url),
-        )
-        self.assertEqual(
-            {**origin_visit3, 'snapshot': self.complete_snapshot['id']},
-            self.storage.origin_visit_get_latest(
-                origin_url, require_snapshot=True),
-        )
+        swh_storage.snapshot_add([data.complete_snapshot])
+        swh_storage.origin_visit_update(
+            origin_url, visit3_id, snapshot=data.complete_snapshot['id'])
+        assert {
+            **origin_visit1,
+            'snapshot': data.complete_snapshot['id'],
+            'status': 'full'} == swh_storage.origin_visit_get_latest(
+                origin_url, allowed_statuses=['full'])
+        assert {
+            **origin_visit1,
+            'snapshot': data.complete_snapshot['id'],
+            'status': 'full'} == swh_storage.origin_visit_get_latest(
+                origin_url, allowed_statuses=['full'], require_snapshot=True)
+        assert {
+            **origin_visit3,
+            'snapshot': data.complete_snapshot['id']
+            } == swh_storage.origin_visit_get_latest(origin_url)
+
+        assert {
+            **origin_visit3,
+            'snapshot': data.complete_snapshot['id']
+            } == swh_storage.origin_visit_get_latest(
+                origin_url, require_snapshot=True)
 
-    def test_person_fullname_unicity(self):
+    def test_person_fullname_unicity(self, swh_storage):
         # given (person injection through revisions for example)
-        revision = self.revision
+        revision = data.revision
 
         # create a revision with same committer fullname but wo name and email
-        revision2 = copy.deepcopy(self.revision2)
+        revision2 = copy.deepcopy(data.revision2)
         revision2['committer'] = dict(revision['committer'])
         revision2['committer']['email'] = None
         revision2['committer']['name'] = None
 
-        self.storage.revision_add([revision])
-        self.storage.revision_add([revision2])
+        swh_storage.revision_add([revision])
+        swh_storage.revision_add([revision2])
 
         # when getting added revisions
         revisions = list(
-            self.storage.revision_get([revision['id'], revision2['id']]))
+            swh_storage.revision_get([revision['id'], revision2['id']]))
 
         # then
         # check committers are the same
-        self.assertEqual(revisions[0]['committer'],
-                         revisions[1]['committer'])
+        assert revisions[0]['committer'] == revisions[1]['committer']
 
-    def test_snapshot_add_get_empty(self):
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_visit1 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit1)
+    def test_snapshot_add_get_empty(self, swh_storage):
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit1)
         visit_id = origin_visit1['visit']
 
-        actual_result = self.storage.snapshot_add([self.empty_snapshot])
-        self.assertEqual(actual_result, {'snapshot:add': 1})
+        actual_result = swh_storage.snapshot_add([data.empty_snapshot])
+        assert actual_result == {'snapshot:add': 1}
 
-        self.storage.origin_visit_update(
-            origin_id, visit_id, snapshot=self.empty_snapshot['id'])
+        swh_storage.origin_visit_update(
+            origin_id, visit_id, snapshot=data.empty_snapshot['id'])
 
-        by_id = self.storage.snapshot_get(self.empty_snapshot['id'])
-        self.assertEqual(by_id, {**self.empty_snapshot, 'next_branch': None})
+        by_id = swh_storage.snapshot_get(data.empty_snapshot['id'])
+        assert by_id == {**data.empty_snapshot, 'next_branch': None}
 
-        by_ov = self.storage.snapshot_get_by_origin_visit(origin_id, visit_id)
-        self.assertEqual(by_ov, {**self.empty_snapshot, 'next_branch': None})
+        by_ov = swh_storage.snapshot_get_by_origin_visit(origin_id, visit_id)
+        assert by_ov == {**data.empty_snapshot, 'next_branch': None}
 
-        expected_origin = self.origin.copy()
+        expected_origin = data.origin.copy()
         data1 = {
             'origin': expected_origin,
-            'date': self.date_visit1,
+            'date': data.date_visit1,
             'visit': origin_visit1['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'status': 'ongoing',
             'metadata': None,
             'snapshot': None,
         }
         data2 = {
             'origin': expected_origin,
-            'date': self.date_visit1,
+            'date': data.date_visit1,
             'visit': origin_visit1['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'status': 'ongoing',
             'metadata': None,
-            'snapshot': self.empty_snapshot['id'],
-        }
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('origin', expected_origin),
-                          ('origin_visit', data1),
-                          ('snapshot', self.empty_snapshot),
-                          ('origin_visit', data2)])
-
-    def test_snapshot_add_get_complete(self):
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_visit1 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit1)
+            'snapshot': data.empty_snapshot['id'],
+        }
+        assert list(swh_storage.journal_writer.objects) == \
+            [('origin', expected_origin),
+             ('origin_visit', data1),
+             ('snapshot', data.empty_snapshot),
+             ('origin_visit', data2)]
+
+    def test_snapshot_add_get_complete(self, swh_storage):
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit1)
         visit_id = origin_visit1['visit']
 
-        actual_result = self.storage.snapshot_add([self.complete_snapshot])
-        self.storage.origin_visit_update(
-            origin_id, visit_id, snapshot=self.complete_snapshot['id'])
-        self.assertEqual(actual_result, {'snapshot:add': 1})
+        actual_result = swh_storage.snapshot_add([data.complete_snapshot])
+        swh_storage.origin_visit_update(
+            origin_id, visit_id, snapshot=data.complete_snapshot['id'])
+        assert actual_result == {'snapshot:add': 1}
 
-        by_id = self.storage.snapshot_get(self.complete_snapshot['id'])
-        self.assertEqual(by_id,
-                         {**self.complete_snapshot, 'next_branch': None})
+        by_id = swh_storage.snapshot_get(data.complete_snapshot['id'])
+        assert by_id == {**data.complete_snapshot, 'next_branch': None}
 
-        by_ov = self.storage.snapshot_get_by_origin_visit(origin_id, visit_id)
-        self.assertEqual(by_ov,
-                         {**self.complete_snapshot, 'next_branch': None})
+        by_ov = swh_storage.snapshot_get_by_origin_visit(origin_id, visit_id)
+        assert by_ov == {**data.complete_snapshot, 'next_branch': None}
 
-    def test_snapshot_add_many(self):
-        actual_result = self.storage.snapshot_add(
-            [self.snapshot, self.complete_snapshot])
-        self.assertEqual(actual_result, {'snapshot:add': 2})
+    def test_snapshot_add_many(self, swh_storage):
+        actual_result = swh_storage.snapshot_add(
+            [data.snapshot, data.complete_snapshot])
+        assert actual_result == {'snapshot:add': 2}
 
-        self.assertEqual(
-            {**self.complete_snapshot, 'next_branch': None},
-            self.storage.snapshot_get(self.complete_snapshot['id']))
+        assert {**data.complete_snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get(data.complete_snapshot['id'])
 
-        self.assertEqual(
-            {**self.snapshot, 'next_branch': None},
-            self.storage.snapshot_get(self.snapshot['id']))
+        assert {**data.snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get(data.snapshot['id'])
 
-    def test_snapshot_add_many_incremental(self):
-        actual_result = self.storage.snapshot_add([self.complete_snapshot])
-        self.assertEqual(actual_result, {'snapshot:add': 1})
+    def test_snapshot_add_many_incremental(self, swh_storage):
+        actual_result = swh_storage.snapshot_add([data.complete_snapshot])
+        assert actual_result == {'snapshot:add': 1}
 
-        actual_result2 = self.storage.snapshot_add(
-            [self.snapshot, self.complete_snapshot])
-        self.assertEqual(actual_result2, {'snapshot:add': 1})
+        actual_result2 = swh_storage.snapshot_add(
+            [data.snapshot, data.complete_snapshot])
+        assert actual_result2 == {'snapshot:add': 1}
 
-        self.assertEqual(
-            {**self.complete_snapshot, 'next_branch': None},
-            self.storage.snapshot_get(self.complete_snapshot['id']))
+        assert {**data.complete_snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get(data.complete_snapshot['id'])
 
-        self.assertEqual(
-            {**self.snapshot, 'next_branch': None},
-            self.storage.snapshot_get(self.snapshot['id']))
+        assert {**data.snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get(data.snapshot['id'])
 
-    def test_snapshot_add_twice(self):
-        actual_result = self.storage.snapshot_add([self.empty_snapshot])
-        self.assertEqual(actual_result, {'snapshot:add': 1})
+    def test_snapshot_add_twice(self, swh_storage):
+        actual_result = swh_storage.snapshot_add([data.empty_snapshot])
+        assert actual_result == {'snapshot:add': 1}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('snapshot', self.empty_snapshot)])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('snapshot', data.empty_snapshot)]
 
-        actual_result = self.storage.snapshot_add([self.snapshot])
-        self.assertEqual(actual_result, {'snapshot:add': 1})
+        actual_result = swh_storage.snapshot_add([data.snapshot])
+        assert actual_result == {'snapshot:add': 1}
 
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('snapshot', self.empty_snapshot),
-                          ('snapshot', self.snapshot)])
+        assert list(swh_storage.journal_writer.objects) \
+            == [('snapshot', data.empty_snapshot),
+                ('snapshot', data.snapshot)]
 
-    def test_snapshot_add_validation(self):
-        snap = copy.deepcopy(self.snapshot)
+    def test_snapshot_add_validation(self, swh_storage):
+        snap = copy.deepcopy(data.snapshot)
         snap['branches'][b'foo'] = {'target_type': 'revision'}
 
-        with self.assertRaisesRegex(KeyError, 'target'):
-            self.storage.snapshot_add([snap])
+        with pytest.raises(KeyError, match='target'):
+            swh_storage.snapshot_add([snap])
 
-        snap = copy.deepcopy(self.snapshot)
+        snap = copy.deepcopy(data.snapshot)
         snap['branches'][b'foo'] = {'target': b'\x42'*20}
 
-        with self.assertRaisesRegex(KeyError, 'target_type'):
-            self.storage.snapshot_add([snap])
+        with pytest.raises(KeyError, match='target_type'):
+            swh_storage.snapshot_add([snap])
 
-    def test_snapshot_add_count_branches(self):
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_visit1 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit1)
+    def test_snapshot_add_count_branches(self, swh_storage):
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit1)
         visit_id = origin_visit1['visit']
 
-        actual_result = self.storage.snapshot_add([self.complete_snapshot])
-        self.storage.origin_visit_update(
-            origin_id, visit_id, snapshot=self.complete_snapshot['id'])
-        self.assertEqual(actual_result, {'snapshot:add': 1})
+        actual_result = swh_storage.snapshot_add([data.complete_snapshot])
+        swh_storage.origin_visit_update(
+            origin_id, visit_id, snapshot=data.complete_snapshot['id'])
+        assert actual_result == {'snapshot:add': 1}
 
-        snp_id = self.complete_snapshot['id']
-        snp_size = self.storage.snapshot_count_branches(snp_id)
+        snp_id = data.complete_snapshot['id']
+        snp_size = swh_storage.snapshot_count_branches(snp_id)
 
         expected_snp_size = {
             'alias': 1,
             'content': 1,
             'directory': 2,
             'release': 1,
             'revision': 1,
             'snapshot': 1,
             None: 1
         }
+        assert snp_size == expected_snp_size
 
-        self.assertEqual(snp_size, expected_snp_size)
-
-    def test_snapshot_add_get_paginated(self):
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_visit1 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit1)
+    def test_snapshot_add_get_paginated(self, swh_storage):
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit1)
         visit_id = origin_visit1['visit']
 
-        self.storage.snapshot_add([self.complete_snapshot])
-        self.storage.origin_visit_update(
+        swh_storage.snapshot_add([data.complete_snapshot])
+        swh_storage.origin_visit_update(
             origin_id, visit_id,
-            snapshot=self.complete_snapshot['id'])
+            snapshot=data.complete_snapshot['id'])
 
-        snp_id = self.complete_snapshot['id']
-        branches = self.complete_snapshot['branches']
+        snp_id = data.complete_snapshot['id']
+        branches = data.complete_snapshot['branches']
         branch_names = list(sorted(branches))
 
         # Test branch_from
-
-        snapshot = self.storage.snapshot_get_branches(snp_id,
-                                                      branches_from=b'release')
+        snapshot = swh_storage.snapshot_get_branches(
+            snp_id, branches_from=b'release')
 
         rel_idx = branch_names.index(b'release')
         expected_snapshot = {
             'id': snp_id,
             'branches': {
                 name: branches[name]
                 for name in branch_names[rel_idx:]
             },
             'next_branch': None,
         }
 
-        self.assertEqual(snapshot, expected_snapshot)
+        assert snapshot == expected_snapshot
 
         # Test branches_count
-
-        snapshot = self.storage.snapshot_get_branches(snp_id,
-                                                      branches_count=1)
+        snapshot = swh_storage.snapshot_get_branches(
+            snp_id, branches_count=1)
 
         expected_snapshot = {
             'id': snp_id,
             'branches': {
                 branch_names[0]: branches[branch_names[0]],
             },
             'next_branch': b'content',
         }
-        self.assertEqual(snapshot, expected_snapshot)
+        assert snapshot == expected_snapshot
 
         # test branch_from + branches_count
 
-        snapshot = self.storage.snapshot_get_branches(
+        snapshot = swh_storage.snapshot_get_branches(
             snp_id, branches_from=b'directory', branches_count=3)
 
         dir_idx = branch_names.index(b'directory')
         expected_snapshot = {
             'id': snp_id,
             'branches': {
                 name: branches[name]
                 for name in branch_names[dir_idx:dir_idx + 3]
             },
             'next_branch': branch_names[dir_idx + 3],
         }
 
-        self.assertEqual(snapshot, expected_snapshot)
+        assert snapshot == expected_snapshot
 
-    def test_snapshot_add_get_filtered(self):
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_visit1 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit1)
+    def test_snapshot_add_get_filtered(self, swh_storage):
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit1)
         visit_id = origin_visit1['visit']
 
-        self.storage.snapshot_add([self.complete_snapshot])
-        self.storage.origin_visit_update(
-            origin_id, visit_id, snapshot=self.complete_snapshot['id'])
+        swh_storage.snapshot_add([data.complete_snapshot])
+        swh_storage.origin_visit_update(
+            origin_id, visit_id, snapshot=data.complete_snapshot['id'])
 
-        snp_id = self.complete_snapshot['id']
-        branches = self.complete_snapshot['branches']
+        snp_id = data.complete_snapshot['id']
+        branches = data.complete_snapshot['branches']
 
-        snapshot = self.storage.snapshot_get_branches(
+        snapshot = swh_storage.snapshot_get_branches(
             snp_id, target_types=['release', 'revision'])
 
         expected_snapshot = {
             'id': snp_id,
             'branches': {
                 name: tgt
                 for name, tgt in branches.items()
                 if tgt and tgt['target_type'] in ['release', 'revision']
             },
             'next_branch': None,
         }
 
-        self.assertEqual(snapshot, expected_snapshot)
+        assert snapshot == expected_snapshot
 
-        snapshot = self.storage.snapshot_get_branches(snp_id,
-                                                      target_types=['alias'])
+        snapshot = swh_storage.snapshot_get_branches(
+            snp_id, target_types=['alias'])
 
         expected_snapshot = {
             'id': snp_id,
             'branches': {
                 name: tgt
                 for name, tgt in branches.items()
                 if tgt and tgt['target_type'] == 'alias'
             },
             'next_branch': None,
         }
 
-        self.assertEqual(snapshot, expected_snapshot)
+        assert snapshot == expected_snapshot
 
-    def test_snapshot_add_get_filtered_and_paginated(self):
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_visit1 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit1)
+    def test_snapshot_add_get_filtered_and_paginated(self, swh_storage):
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit1)
         visit_id = origin_visit1['visit']
 
-        self.storage.snapshot_add([self.complete_snapshot])
-        self.storage.origin_visit_update(
-            origin_id, visit_id, snapshot=self.complete_snapshot['id'])
+        swh_storage.snapshot_add([data.complete_snapshot])
+        swh_storage.origin_visit_update(
+            origin_id, visit_id, snapshot=data.complete_snapshot['id'])
 
-        snp_id = self.complete_snapshot['id']
-        branches = self.complete_snapshot['branches']
+        snp_id = data.complete_snapshot['id']
+        branches = data.complete_snapshot['branches']
         branch_names = list(sorted(branches))
 
         # Test branch_from
 
-        snapshot = self.storage.snapshot_get_branches(
+        snapshot = swh_storage.snapshot_get_branches(
             snp_id, target_types=['directory', 'release'],
             branches_from=b'directory2')
 
         expected_snapshot = {
             'id': snp_id,
             'branches': {
                 name: branches[name]
                 for name in (b'directory2', b'release')
             },
             'next_branch': None,
         }
 
-        self.assertEqual(snapshot, expected_snapshot)
+        assert snapshot == expected_snapshot
 
         # Test branches_count
 
-        snapshot = self.storage.snapshot_get_branches(
+        snapshot = swh_storage.snapshot_get_branches(
             snp_id, target_types=['directory', 'release'],
             branches_count=1)
 
         expected_snapshot = {
             'id': snp_id,
             'branches': {
                 b'directory': branches[b'directory']
             },
             'next_branch': b'directory2',
         }
-        self.assertEqual(snapshot, expected_snapshot)
+        assert snapshot == expected_snapshot
 
         # Test branches_count
 
-        snapshot = self.storage.snapshot_get_branches(
+        snapshot = swh_storage.snapshot_get_branches(
             snp_id, target_types=['directory', 'release'],
             branches_count=2)
 
         expected_snapshot = {
             'id': snp_id,
             'branches': {
                 name: branches[name]
                 for name in (b'directory', b'directory2')
             },
             'next_branch': b'release',
         }
-        self.assertEqual(snapshot, expected_snapshot)
+        assert snapshot == expected_snapshot
 
         # test branch_from + branches_count
 
-        snapshot = self.storage.snapshot_get_branches(
+        snapshot = swh_storage.snapshot_get_branches(
             snp_id, target_types=['directory', 'release'],
             branches_from=b'directory2', branches_count=1)
 
         dir_idx = branch_names.index(b'directory2')
         expected_snapshot = {
             'id': snp_id,
             'branches': {
                 branch_names[dir_idx]: branches[branch_names[dir_idx]],
             },
             'next_branch': b'release',
         }
 
-        self.assertEqual(snapshot, expected_snapshot)
+        assert snapshot == expected_snapshot
 
-    def test_snapshot_add_get(self):
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_visit1 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit1)
+    def test_snapshot_add_get(self, swh_storage):
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit1)
         visit_id = origin_visit1['visit']
 
-        self.storage.snapshot_add([self.snapshot])
-        self.storage.origin_visit_update(
-            origin_id, visit_id, snapshot=self.snapshot['id'])
+        swh_storage.snapshot_add([data.snapshot])
+        swh_storage.origin_visit_update(
+            origin_id, visit_id, snapshot=data.snapshot['id'])
 
-        by_id = self.storage.snapshot_get(self.snapshot['id'])
-        self.assertEqual(by_id, {**self.snapshot, 'next_branch': None})
+        by_id = swh_storage.snapshot_get(data.snapshot['id'])
+        assert by_id == {**data.snapshot, 'next_branch': None}
 
-        by_ov = self.storage.snapshot_get_by_origin_visit(origin_id, visit_id)
-        self.assertEqual(by_ov, {**self.snapshot, 'next_branch': None})
+        by_ov = swh_storage.snapshot_get_by_origin_visit(origin_id, visit_id)
+        assert by_ov == {**data.snapshot, 'next_branch': None}
 
-        origin_visit_info = self.storage.origin_visit_get_by(origin_id,
-                                                             visit_id)
-        self.assertEqual(origin_visit_info['snapshot'], self.snapshot['id'])
+        origin_visit_info = swh_storage.origin_visit_get_by(
+            origin_id, visit_id)
+        assert origin_visit_info['snapshot'] == data.snapshot['id']
 
-    def test_snapshot_add_nonexistent_visit(self):
-        origin_id = self.storage.origin_add_one(self.origin)
+    def test_snapshot_add_nonexistent_visit(self, swh_storage):
+        origin_id = swh_storage.origin_add_one(data.origin)
         visit_id = 54164461156
 
-        self.journal_writer.objects[:] = []
+        swh_storage.journal_writer.objects[:] = []
 
-        self.storage.snapshot_add([self.snapshot])
+        swh_storage.snapshot_add([data.snapshot])
 
-        with self.assertRaises(ValueError):
-            self.storage.origin_visit_update(
-                origin_id, visit_id, snapshot=self.snapshot['id'])
+        with pytest.raises(ValueError):
+            swh_storage.origin_visit_update(
+                origin_id, visit_id, snapshot=data.snapshot['id'])
 
-        self.assertEqual(list(self.journal_writer.objects), [
-            ('snapshot', self.snapshot)])
+        assert list(swh_storage.journal_writer.objects) == [
+            ('snapshot', data.snapshot)]
 
-    def test_snapshot_add_twice__by_origin_visit(self):
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_visit1 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit1)
+    def test_snapshot_add_twice__by_origin_visit(self, swh_storage):
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit1)
         visit1_id = origin_visit1['visit']
-        self.storage.snapshot_add([self.snapshot])
-        self.storage.origin_visit_update(
-            origin_id, visit1_id, snapshot=self.snapshot['id'])
+        swh_storage.snapshot_add([data.snapshot])
+        swh_storage.origin_visit_update(
+            origin_id, visit1_id, snapshot=data.snapshot['id'])
 
-        by_ov1 = self.storage.snapshot_get_by_origin_visit(origin_id,
-                                                           visit1_id)
-        self.assertEqual(by_ov1, {**self.snapshot, 'next_branch': None})
+        by_ov1 = swh_storage.snapshot_get_by_origin_visit(
+            origin_id, visit1_id)
+        assert by_ov1 == {**data.snapshot, 'next_branch': None}
 
-        origin_visit2 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit2)
+        origin_visit2 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit2)
         visit2_id = origin_visit2['visit']
 
-        self.storage.snapshot_add([self.snapshot])
-        self.storage.origin_visit_update(
-            origin_id, visit2_id, snapshot=self.snapshot['id'])
+        swh_storage.snapshot_add([data.snapshot])
+        swh_storage.origin_visit_update(
+            origin_id, visit2_id, snapshot=data.snapshot['id'])
 
-        by_ov2 = self.storage.snapshot_get_by_origin_visit(origin_id,
-                                                           visit2_id)
-        self.assertEqual(by_ov2, {**self.snapshot, 'next_branch': None})
+        by_ov2 = swh_storage.snapshot_get_by_origin_visit(
+            origin_id, visit2_id)
+        assert by_ov2 == {**data.snapshot, 'next_branch': None}
 
-        expected_origin = self.origin.copy()
+        expected_origin = data.origin.copy()
         data1 = {
             'origin': expected_origin,
-            'date': self.date_visit1,
+            'date': data.date_visit1,
             'visit': origin_visit1['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'status': 'ongoing',
             'metadata': None,
             'snapshot': None,
         }
         data2 = {
             'origin': expected_origin,
-            'date': self.date_visit1,
+            'date': data.date_visit1,
             'visit': origin_visit1['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'status': 'ongoing',
             'metadata': None,
-            'snapshot': self.snapshot['id'],
+            'snapshot': data.snapshot['id'],
         }
         data3 = {
             'origin': expected_origin,
-            'date': self.date_visit2,
+            'date': data.date_visit2,
             'visit': origin_visit2['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'status': 'ongoing',
             'metadata': None,
             'snapshot': None,
         }
         data4 = {
             'origin': expected_origin,
-            'date': self.date_visit2,
+            'date': data.date_visit2,
             'visit': origin_visit2['visit'],
-            'type': self.origin['type'],
+            'type': data.origin['type'],
             'status': 'ongoing',
             'metadata': None,
-            'snapshot': self.snapshot['id'],
-        }
-        self.assertEqual(list(self.journal_writer.objects),
-                         [('origin', expected_origin),
-                          ('origin_visit', data1),
-                          ('snapshot', self.snapshot),
-                          ('origin_visit', data2),
-                          ('origin_visit', data3),
-                          ('origin_visit', data4)])
-
-    @settings(deadline=None)  # this test is very slow
-    @given(strategies.booleans())
-    def test_snapshot_get_latest(self, use_url):
+            'snapshot': data.snapshot['id'],
+        }
+        assert list(swh_storage.journal_writer.objects) \
+            == [('origin', expected_origin),
+                ('origin_visit', data1),
+                ('snapshot', data.snapshot),
+                ('origin_visit', data2),
+                ('origin_visit', data3),
+                ('origin_visit', data4)]
+
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_snapshot_get_latest(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
-
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_id_or_url = self.origin['url'] if use_url else origin_id
-        origin_visit1 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit1)
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_url = data.origin['url']
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit1)
         visit1_id = origin_visit1['visit']
-        origin_visit2 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit2)
+        origin_visit2 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit2)
         visit2_id = origin_visit2['visit']
 
         # Add a visit with the same date as the previous one
-        origin_visit3 = self.storage.origin_visit_add(origin_id,
-                                                      self.date_visit2)
+        origin_visit3 = swh_storage.origin_visit_add(
+            origin_id, data.date_visit2)
         visit3_id = origin_visit3['visit']
 
         # Two visits, both with no snapshot: latest snapshot is None
-        self.assertIsNone(self.storage.snapshot_get_latest(
-            origin_id_or_url))
+        assert swh_storage.snapshot_get_latest(origin_url) is None
 
         # Add snapshot to visit1, latest snapshot = visit 1 snapshot
-        self.storage.snapshot_add([self.complete_snapshot])
-        self.storage.origin_visit_update(
-            origin_id, visit1_id, snapshot=self.complete_snapshot['id'])
-        self.assertEqual({**self.complete_snapshot, 'next_branch': None},
-                         self.storage.snapshot_get_latest(
-                             origin_id_or_url))
+        swh_storage.snapshot_add([data.complete_snapshot])
+        swh_storage.origin_visit_update(
+            origin_id, visit1_id, snapshot=data.complete_snapshot['id'])
+        assert {**data.complete_snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get_latest(origin_url)
 
         # Status filter: all three visits are status=ongoing, so no snapshot
         # returned
-        self.assertIsNone(
-            self.storage.snapshot_get_latest(
-                origin_id_or_url,
-                allowed_statuses=['full'])
-        )
+        assert swh_storage.snapshot_get_latest(
+                origin_url,
+                allowed_statuses=['full']) is None
 
         # Mark the first visit as completed and check status filter again
-        self.storage.origin_visit_update(origin_id, visit1_id, status='full')
-        self.assertEqual(
-            {**self.complete_snapshot, 'next_branch': None},
-            self.storage.snapshot_get_latest(
-                origin_id_or_url,
-                allowed_statuses=['full']),
-        )
+        swh_storage.origin_visit_update(origin_id, visit1_id, status='full')
+        assert {**data.complete_snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get_latest(
+                origin_url,
+                allowed_statuses=['full'])
 
         # Add snapshot to visit2 and check that the new snapshot is returned
-        self.storage.snapshot_add([self.empty_snapshot])
-        self.storage.origin_visit_update(
-            origin_id, visit2_id, snapshot=self.empty_snapshot['id'])
-        self.assertEqual({**self.empty_snapshot, 'next_branch': None},
-                         self.storage.snapshot_get_latest(origin_id))
+        swh_storage.snapshot_add([data.empty_snapshot])
+        swh_storage.origin_visit_update(
+            origin_id, visit2_id, snapshot=data.empty_snapshot['id'])
+        assert {**data.empty_snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get_latest(origin_id)
 
         # Check that the status filter is still working
-        self.assertEqual(
-            {**self.complete_snapshot, 'next_branch': None},
-            self.storage.snapshot_get_latest(
-                origin_id_or_url,
-                allowed_statuses=['full']),
-        )
+        assert {**data.complete_snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get_latest(
+                origin_url,
+                allowed_statuses=['full'])
 
         # Add snapshot to visit3 (same date as visit2) and check that
         # the new snapshot is returned
-        self.storage.snapshot_add([self.complete_snapshot])
-        self.storage.origin_visit_update(
-            origin_id, visit3_id, snapshot=self.complete_snapshot['id'])
-        self.assertEqual({**self.complete_snapshot, 'next_branch': None},
-                         self.storage.snapshot_get_latest(
-                             origin_id_or_url))
-
-    @given(strategies.booleans())
-    def test_snapshot_get_latest__missing_snapshot(self, use_url):
+        swh_storage.snapshot_add([data.complete_snapshot])
+        swh_storage.origin_visit_update(
+            origin_id, visit3_id, snapshot=data.complete_snapshot['id'])
+        assert {**data.complete_snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get_latest(origin_url)
+
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_snapshot_get_latest__missing_snapshot(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
-
         # Origin does not exist
-        self.assertIsNone(self.storage.snapshot_get_latest(
-            self.origin['url'] if use_url else 999))
+        origin_url = data.origin['url']
+        assert swh_storage.snapshot_get_latest(origin_url) is None
 
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_id_or_url = self.origin['url'] if use_url else origin_id
-        origin_visit1 = self.storage.origin_visit_add(
-            origin_id_or_url,
-            self.date_visit1)
+        swh_storage.origin_add_one(data.origin)
+        origin_visit1 = swh_storage.origin_visit_add(
+            origin_url,
+            data.date_visit1)
         visit1_id = origin_visit1['visit']
-        origin_visit2 = self.storage.origin_visit_add(
-            origin_id_or_url,
-            self.date_visit2)
+        origin_visit2 = swh_storage.origin_visit_add(
+            origin_url,
+            data.date_visit2)
         visit2_id = origin_visit2['visit']
 
         # Two visits, both with no snapshot: latest snapshot is None
-        self.assertIsNone(self.storage.snapshot_get_latest(
-            origin_id_or_url))
+        assert swh_storage.snapshot_get_latest(origin_url) is None
 
         # Add unknown snapshot to visit1, check that the inconsistency is
         # detected
-        self.storage.origin_visit_update(
-            origin_id_or_url,
-            visit1_id, snapshot=self.complete_snapshot['id'])
-        with self.assertRaises(ValueError):
-            self.storage.snapshot_get_latest(
-                origin_id_or_url)
+        swh_storage.origin_visit_update(
+            origin_url,
+            visit1_id, snapshot=data.complete_snapshot['id'])
+        with pytest.raises(ValueError):
+            swh_storage.snapshot_get_latest(
+                origin_url)
 
         # Status filter: both visits are status=ongoing, so no snapshot
         # returned
-        self.assertIsNone(
-            self.storage.snapshot_get_latest(
-                origin_id_or_url,
-                allowed_statuses=['full'])
-        )
+        assert swh_storage.snapshot_get_latest(
+            origin_url,
+            allowed_statuses=['full']) is None
 
         # Mark the first visit as completed and check status filter again
-        self.storage.origin_visit_update(
-            origin_id_or_url,
+        swh_storage.origin_visit_update(
+            origin_url,
             visit1_id, status='full')
-        with self.assertRaises(ValueError):
-            self.storage.snapshot_get_latest(
-                origin_id_or_url,
+        with pytest.raises(ValueError):
+            swh_storage.snapshot_get_latest(
+                origin_url,
                 allowed_statuses=['full']),
 
         # Actually add the snapshot and check status filter again
-        self.storage.snapshot_add([self.complete_snapshot])
-        self.assertEqual(
-            {**self.complete_snapshot, 'next_branch': None},
-            self.storage.snapshot_get_latest(
-                origin_id_or_url)
-        )
+        swh_storage.snapshot_add([data.complete_snapshot])
+        assert {**data.complete_snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get_latest(origin_url)
 
         # Add unknown snapshot to visit2 and check that the inconsistency
         # is detected
-        self.storage.origin_visit_update(
-            origin_id_or_url,
-            visit2_id, snapshot=self.snapshot['id'])
-        with self.assertRaises(ValueError):
-            self.storage.snapshot_get_latest(
-                origin_id_or_url)
+        swh_storage.origin_visit_update(
+            origin_url,
+            visit2_id, snapshot=data.snapshot['id'])
+        with pytest.raises(ValueError):
+            swh_storage.snapshot_get_latest(
+                origin_url)
 
         # Actually add that snapshot and check that the new one is returned
-        self.storage.snapshot_add([self.snapshot])
-        self.assertEqual(
-            {**self.snapshot, 'next_branch': None},
-            self.storage.snapshot_get_latest(
-                origin_id_or_url)
-        )
+        swh_storage.snapshot_add([data.snapshot])
+        assert{**data.snapshot, 'next_branch': None} \
+            == swh_storage.snapshot_get_latest(origin_url)
 
-    def test_stat_counters(self):
+    def test_stat_counters(self, swh_storage):
         expected_keys = ['content', 'directory',
                          'origin', 'revision']
 
         # Initially, all counters are 0
 
-        self.storage.refresh_stat_counters()
-        counters = self.storage.stat_counters()
-        self.assertTrue(set(expected_keys) <= set(counters))
+        swh_storage.refresh_stat_counters()
+        counters = swh_storage.stat_counters()
+        assert set(expected_keys) <= set(counters)
         for key in expected_keys:
-            self.assertEqual(counters[key], 0)
+            assert counters[key] == 0
 
         # Add a content. Only the content counter should increase.
 
-        self.storage.content_add([self.cont])
+        swh_storage.content_add([data.cont])
 
-        self.storage.refresh_stat_counters()
-        counters = self.storage.stat_counters()
+        swh_storage.refresh_stat_counters()
+        counters = swh_storage.stat_counters()
 
-        self.assertTrue(set(expected_keys) <= set(counters))
+        assert set(expected_keys) <= set(counters)
         for key in expected_keys:
             if key != 'content':
-                self.assertEqual(counters[key], 0)
-        self.assertEqual(counters['content'], 1)
+                assert counters[key] == 0
+        assert counters['content'] == 1
 
         # Add other objects. Check their counter increased as well.
 
-        self.storage.origin_add_one(self.origin2)
-        origin_visit1 = self.storage.origin_visit_add(
-            self.origin2['url'], date=self.date_visit2)
-        self.storage.snapshot_add([self.snapshot])
-        self.storage.origin_visit_update(
-            self.origin2['url'], origin_visit1['visit'],
-            snapshot=self.snapshot['id'])
-        self.storage.directory_add([self.dir])
-        self.storage.revision_add([self.revision])
-        self.storage.release_add([self.release])
-
-        self.storage.refresh_stat_counters()
-        counters = self.storage.stat_counters()
-        self.assertEqual(counters['content'], 1)
-        self.assertEqual(counters['directory'], 1)
-        self.assertEqual(counters['snapshot'], 1)
-        self.assertEqual(counters['origin'], 1)
-        self.assertEqual(counters['origin_visit'], 1)
-        self.assertEqual(counters['revision'], 1)
-        self.assertEqual(counters['release'], 1)
-        self.assertEqual(counters['snapshot'], 1)
+        swh_storage.origin_add_one(data.origin2)
+        origin_visit1 = swh_storage.origin_visit_add(
+            data.origin2['url'], date=data.date_visit2)
+        swh_storage.snapshot_add([data.snapshot])
+        swh_storage.origin_visit_update(
+            data.origin2['url'], origin_visit1['visit'],
+            snapshot=data.snapshot['id'])
+        swh_storage.directory_add([data.dir])
+        swh_storage.revision_add([data.revision])
+        swh_storage.release_add([data.release])
+
+        swh_storage.refresh_stat_counters()
+        counters = swh_storage.stat_counters()
+        assert counters['content'] == 1
+        assert counters['directory'] == 1
+        assert counters['snapshot'] == 1
+        assert counters['origin'] == 1
+        assert counters['origin_visit'] == 1
+        assert counters['revision'] == 1
+        assert counters['release'] == 1
+        assert counters['snapshot'] == 1
         if 'person' in counters:
-            self.assertEqual(counters['person'], 3)
+            assert counters['person'] == 3
 
-    def test_content_find_ctime(self):
-        cont = self.cont.copy()
+    def test_content_find_ctime(self, swh_storage):
+        cont = data.cont.copy()
         del cont['data']
         now = datetime.datetime.now(tz=datetime.timezone.utc)
         cont['ctime'] = now
-        self.storage.content_add_metadata([cont])
+        swh_storage.content_add_metadata([cont])
 
-        actually_present = self.storage.content_find({'sha1': cont['sha1']})
+        actually_present = swh_storage.content_find({'sha1': cont['sha1']})
 
         # check ctime up to one second
         dt = actually_present[0]['ctime'] - now
-        self.assertLessEqual(abs(dt.total_seconds()), 1, dt)
+        assert abs(dt.total_seconds()) <= 1
         del actually_present[0]['ctime']
 
-        self.assertEqual(actually_present[0], {
+        assert actually_present[0] == {
             'sha1': cont['sha1'],
             'sha256': cont['sha256'],
             'sha1_git': cont['sha1_git'],
             'blake2s256': cont['blake2s256'],
             'length': cont['length'],
             'status': 'visible'
-        })
+        }
 
-    def test_content_find_with_present_content(self):
+    def test_content_find_with_present_content(self, swh_storage):
         # 1. with something to find
-        cont = self.cont
-        self.storage.content_add([cont, self.cont2])
+        cont = data.cont
+        swh_storage.content_add([cont, data.cont2])
 
-        actually_present = self.storage.content_find(
+        actually_present = swh_storage.content_find(
             {'sha1': cont['sha1']}
             )
-        self.assertEqual(1, len(actually_present))
+        assert 1 == len(actually_present)
         actually_present[0].pop('ctime')
 
-        self.assertEqual(actually_present[0], {
+        assert actually_present[0] == {
                 'sha1': cont['sha1'],
                 'sha256': cont['sha256'],
                 'sha1_git': cont['sha1_git'],
                 'blake2s256': cont['blake2s256'],
                 'length': cont['length'],
                 'status': 'visible'
-            })
+            }
 
         # 2. with something to find
-        actually_present = self.storage.content_find(
+        actually_present = swh_storage.content_find(
             {'sha1_git': cont['sha1_git']})
-        self.assertEqual(1, len(actually_present))
+        assert 1 == len(actually_present)
 
         actually_present[0].pop('ctime')
-        self.assertEqual(actually_present[0], {
+        assert actually_present[0] == {
                 'sha1': cont['sha1'],
                 'sha256': cont['sha256'],
                 'sha1_git': cont['sha1_git'],
                 'blake2s256': cont['blake2s256'],
                 'length': cont['length'],
                 'status': 'visible'
-            })
+            }
 
         # 3. with something to find
-        actually_present = self.storage.content_find(
+        actually_present = swh_storage.content_find(
             {'sha256': cont['sha256']})
-        self.assertEqual(1, len(actually_present))
+        assert 1 == len(actually_present)
 
         actually_present[0].pop('ctime')
-        self.assertEqual(actually_present[0], {
+        assert actually_present[0] == {
                 'sha1': cont['sha1'],
                 'sha256': cont['sha256'],
                 'sha1_git': cont['sha1_git'],
                 'blake2s256': cont['blake2s256'],
                 'length': cont['length'],
                 'status': 'visible'
-            })
+            }
 
         # 4. with something to find
-        actually_present = self.storage.content_find({
+        actually_present = swh_storage.content_find({
             'sha1': cont['sha1'],
             'sha1_git': cont['sha1_git'],
             'sha256': cont['sha256'],
             'blake2s256': cont['blake2s256'],
         })
-        self.assertEqual(1, len(actually_present))
+        assert 1 == len(actually_present)
 
         actually_present[0].pop('ctime')
-        self.assertEqual(actually_present[0], {
+        assert actually_present[0] == {
                 'sha1': cont['sha1'],
                 'sha256': cont['sha256'],
                 'sha1_git': cont['sha1_git'],
                 'blake2s256': cont['blake2s256'],
                 'length': cont['length'],
                 'status': 'visible'
-            })
+            }
 
-    def test_content_find_with_non_present_content(self):
+    def test_content_find_with_non_present_content(self, swh_storage):
         # 1. with something that does not exist
-        missing_cont = self.missing_cont
+        missing_cont = data.missing_cont
 
-        actually_present = self.storage.content_find(
+        actually_present = swh_storage.content_find(
             {'sha1': missing_cont['sha1']})
 
-        self.assertEqual(actually_present, [])
+        assert actually_present == []
 
         # 2. with something that does not exist
-        actually_present = self.storage.content_find(
+        actually_present = swh_storage.content_find(
             {'sha1_git': missing_cont['sha1_git']})
 
-        self.assertEqual(actually_present, [])
+        assert actually_present == []
 
         # 3. with something that does not exist
-        actually_present = self.storage.content_find(
+        actually_present = swh_storage.content_find(
             {'sha256': missing_cont['sha256']})
 
-        self.assertEqual(actually_present, [])
+        assert actually_present == []
 
-    def test_content_find_with_duplicate_input(self):
-        cont1 = self.cont
+    def test_content_find_with_duplicate_input(self, swh_storage):
+        cont1 = data.cont
         duplicate_cont = cont1.copy()
 
         # Create fake data with colliding sha256 and blake2s256
         sha1_array = bytearray(duplicate_cont['sha1'])
         sha1_array[0] += 1
         duplicate_cont['sha1'] = bytes(sha1_array)
         sha1git_array = bytearray(duplicate_cont['sha1_git'])
         sha1git_array[0] += 1
         duplicate_cont['sha1_git'] = bytes(sha1git_array)
         # Inject the data
-        self.storage.content_add([cont1, duplicate_cont])
+        swh_storage.content_add([cont1, duplicate_cont])
         finder = {'blake2s256': duplicate_cont['blake2s256'],
                   'sha256': duplicate_cont['sha256']}
-        actual_result = list(self.storage.content_find(finder))
+        actual_result = list(swh_storage.content_find(finder))
 
         cont1.pop('data')
         duplicate_cont.pop('data')
         actual_result[0].pop('ctime')
         actual_result[1].pop('ctime')
 
         expected_result = [
            cont1, duplicate_cont
         ]
-        self.assertCountEqual(expected_result, actual_result)
+        for result in expected_result:
+            assert result in actual_result
 
-    def test_content_find_with_duplicate_sha256(self):
-        cont1 = self.cont
+    def test_content_find_with_duplicate_sha256(self, swh_storage):
+        cont1 = data.cont
         duplicate_cont = cont1.copy()
 
-        # Create fake data with colliding sha256 and blake2s256
-        sha1_array = bytearray(duplicate_cont['sha1'])
-        sha1_array[0] += 1
-        duplicate_cont['sha1'] = bytes(sha1_array)
-        sha1git_array = bytearray(duplicate_cont['sha1_git'])
-        sha1git_array[0] += 1
-        duplicate_cont['sha1_git'] = bytes(sha1git_array)
-        blake2s256_array = bytearray(duplicate_cont['blake2s256'])
-        blake2s256_array[0] += 1
-        duplicate_cont['blake2s256'] = bytes(blake2s256_array)
-        self.storage.content_add([cont1, duplicate_cont])
+        # Create fake data with colliding sha256
+        for hashalgo in ('sha1', 'sha1_git', 'blake2s256'):
+            value = bytearray(duplicate_cont[hashalgo])
+            value[0] += 1
+            duplicate_cont[hashalgo] = bytes(value)
+        swh_storage.content_add([cont1, duplicate_cont])
+
         finder = {
             'sha256': duplicate_cont['sha256']
             }
-        actual_result = list(self.storage.content_find(finder))
+        actual_result = list(swh_storage.content_find(finder))
+        assert len(actual_result) == 2
 
         cont1.pop('data')
         duplicate_cont.pop('data')
         actual_result[0].pop('ctime')
         actual_result[1].pop('ctime')
         expected_result = [
             cont1, duplicate_cont
         ]
-        self.assertCountEqual(expected_result, actual_result)
+        assert expected_result == sorted(actual_result,
+                                         key=lambda x: x['sha1'])
+
         # Find with both sha256 and blake2s256
         finder = {
             'sha256': duplicate_cont['sha256'],
             'blake2s256': duplicate_cont['blake2s256']
         }
-        actual_result = list(self.storage.content_find(finder))
-
+        actual_result = list(swh_storage.content_find(finder))
+        assert len(actual_result) == 1
         actual_result[0].pop('ctime')
 
-        expected_result = [
-            duplicate_cont
-        ]
-        self.assertCountEqual(expected_result, actual_result)
+        expected_result = [duplicate_cont]
+        assert actual_result[0] == duplicate_cont
 
-    def test_content_find_with_duplicate_blake2s256(self):
-        cont1 = self.cont
+    def test_content_find_with_duplicate_blake2s256(self, swh_storage):
+        cont1 = data.cont
         duplicate_cont = cont1.copy()
 
         # Create fake data with colliding sha256 and blake2s256
         sha1_array = bytearray(duplicate_cont['sha1'])
         sha1_array[0] += 1
         duplicate_cont['sha1'] = bytes(sha1_array)
         sha1git_array = bytearray(duplicate_cont['sha1_git'])
         sha1git_array[0] += 1
         duplicate_cont['sha1_git'] = bytes(sha1git_array)
         sha256_array = bytearray(duplicate_cont['sha256'])
         sha256_array[0] += 1
         duplicate_cont['sha256'] = bytes(sha256_array)
-        self.storage.content_add([cont1, duplicate_cont])
+        swh_storage.content_add([cont1, duplicate_cont])
         finder = {
             'blake2s256': duplicate_cont['blake2s256']
             }
-        actual_result = list(self.storage.content_find(finder))
+        actual_result = list(swh_storage.content_find(finder))
 
         cont1.pop('data')
         duplicate_cont.pop('data')
         actual_result[0].pop('ctime')
         actual_result[1].pop('ctime')
         expected_result = [
             cont1, duplicate_cont
         ]
-        self.assertCountEqual(expected_result, actual_result)
+        for result in expected_result:
+            assert result in actual_result
+
         # Find with both sha256 and blake2s256
         finder = {
             'sha256': duplicate_cont['sha256'],
             'blake2s256': duplicate_cont['blake2s256']
         }
-        actual_result = list(self.storage.content_find(finder))
+        actual_result = list(swh_storage.content_find(finder))
 
         actual_result[0].pop('ctime')
 
         expected_result = [
             duplicate_cont
         ]
-        self.assertCountEqual(expected_result, actual_result)
+        assert expected_result == actual_result
 
-    def test_content_find_bad_input(self):
+    def test_content_find_bad_input(self, swh_storage):
         # 1. with bad input
-        with self.assertRaises(ValueError):
-            self.storage.content_find({})  # empty is bad
+        with pytest.raises(ValueError):
+            swh_storage.content_find({})  # empty is bad
 
         # 2. with bad input
-        with self.assertRaises(ValueError):
-            self.storage.content_find(
+        with pytest.raises(ValueError):
+            swh_storage.content_find(
                 {'unknown-sha1': 'something'})  # not the right key
 
-    def test_object_find_by_sha1_git(self):
+    def test_object_find_by_sha1_git(self, swh_storage):
         sha1_gits = [b'00000000000000000000']
         expected = {
             b'00000000000000000000': [],
         }
 
-        self.storage.content_add([self.cont])
-        sha1_gits.append(self.cont['sha1_git'])
-        expected[self.cont['sha1_git']] = [{
-            'sha1_git': self.cont['sha1_git'],
+        swh_storage.content_add([data.cont])
+        sha1_gits.append(data.cont['sha1_git'])
+        expected[data.cont['sha1_git']] = [{
+            'sha1_git': data.cont['sha1_git'],
             'type': 'content',
-            'id': self.cont['sha1'],
+            'id': data.cont['sha1'],
         }]
 
-        self.storage.directory_add([self.dir])
-        sha1_gits.append(self.dir['id'])
-        expected[self.dir['id']] = [{
-            'sha1_git': self.dir['id'],
+        swh_storage.directory_add([data.dir])
+        sha1_gits.append(data.dir['id'])
+        expected[data.dir['id']] = [{
+            'sha1_git': data.dir['id'],
             'type': 'directory',
-            'id': self.dir['id'],
+            'id': data.dir['id'],
         }]
 
-        self.storage.revision_add([self.revision])
-        sha1_gits.append(self.revision['id'])
-        expected[self.revision['id']] = [{
-            'sha1_git': self.revision['id'],
+        swh_storage.revision_add([data.revision])
+        sha1_gits.append(data.revision['id'])
+        expected[data.revision['id']] = [{
+            'sha1_git': data.revision['id'],
             'type': 'revision',
-            'id': self.revision['id'],
+            'id': data.revision['id'],
         }]
 
-        self.storage.release_add([self.release])
-        sha1_gits.append(self.release['id'])
-        expected[self.release['id']] = [{
-            'sha1_git': self.release['id'],
+        swh_storage.release_add([data.release])
+        sha1_gits.append(data.release['id'])
+        expected[data.release['id']] = [{
+            'sha1_git': data.release['id'],
             'type': 'release',
-            'id': self.release['id'],
+            'id': data.release['id'],
         }]
 
-        ret = self.storage.object_find_by_sha1_git(sha1_gits)
+        ret = swh_storage.object_find_by_sha1_git(sha1_gits)
         for val in ret.values():
             for obj in val:
                 if 'object_id' in obj:
                     del obj['object_id']
 
-        self.assertEqual(expected, ret)
+        assert expected == ret
 
-    def test_tool_add(self):
+    def test_tool_add(self, swh_storage):
         tool = {
             'name': 'some-unknown-tool',
             'version': 'some-version',
             'configuration': {"debian-package": "some-package"},
         }
 
-        actual_tool = self.storage.tool_get(tool)
-        self.assertIsNone(actual_tool)  # does not exist
+        actual_tool = swh_storage.tool_get(tool)
+        assert actual_tool is None  # does not exist
 
         # add it
-        actual_tools = self.storage.tool_add([tool])
+        actual_tools = swh_storage.tool_add([tool])
 
-        self.assertEqual(len(actual_tools), 1)
+        assert len(actual_tools) == 1
         actual_tool = actual_tools[0]
-        self.assertIsNotNone(actual_tool)  # now it exists
+        assert actual_tool is not None  # now it exists
         new_id = actual_tool.pop('id')
-        self.assertEqual(actual_tool, tool)
+        assert actual_tool == tool
 
-        actual_tools2 = self.storage.tool_add([tool])
+        actual_tools2 = swh_storage.tool_add([tool])
         actual_tool2 = actual_tools2[0]
-        self.assertIsNotNone(actual_tool2)  # now it exists
+        assert actual_tool2 is not None  # now it exists
         new_id2 = actual_tool2.pop('id')
 
-        self.assertEqual(new_id, new_id2)
-        self.assertEqual(actual_tool, actual_tool2)
+        assert new_id == new_id2
+        assert actual_tool == actual_tool2
 
-    def test_tool_add_multiple(self):
+    def test_tool_add_multiple(self, swh_storage):
         tool = {
             'name': 'some-unknown-tool',
             'version': 'some-version',
             'configuration': {"debian-package": "some-package"},
         }
 
-        actual_tools = list(self.storage.tool_add([tool]))
-        self.assertEqual(len(actual_tools), 1)
+        actual_tools = list(swh_storage.tool_add([tool]))
+        assert len(actual_tools) == 1
 
         new_tools = [tool, {
             'name': 'yet-another-tool',
             'version': 'version',
             'configuration': {},
         }]
 
-        actual_tools = self.storage.tool_add(new_tools)
-        self.assertEqual(len(actual_tools), 2)
+        actual_tools = swh_storage.tool_add(new_tools)
+        assert len(actual_tools) == 2
 
         # order not guaranteed, so we iterate over results to check
         for tool in actual_tools:
             _id = tool.pop('id')
-            self.assertIsNotNone(_id)
-            self.assertIn(tool, new_tools)
+            assert _id is not None
+            assert tool in new_tools
 
-    def test_tool_get_missing(self):
+    def test_tool_get_missing(self, swh_storage):
         tool = {
             'name': 'unknown-tool',
             'version': '3.1.0rc2-31-ga2cbb8c',
             'configuration': {"command_line": "nomossa <filepath>"},
         }
 
-        actual_tool = self.storage.tool_get(tool)
+        actual_tool = swh_storage.tool_get(tool)
 
-        self.assertIsNone(actual_tool)
+        assert actual_tool is None
 
-    def test_tool_metadata_get_missing_context(self):
+    def test_tool_metadata_get_missing_context(self, swh_storage):
         tool = {
             'name': 'swh-metadata-translator',
             'version': '0.0.1',
             'configuration': {"context": "unknown-context"},
         }
 
-        actual_tool = self.storage.tool_get(tool)
+        actual_tool = swh_storage.tool_get(tool)
 
-        self.assertIsNone(actual_tool)
+        assert actual_tool is None
 
-    def test_tool_metadata_get(self):
+    def test_tool_metadata_get(self, swh_storage):
         tool = {
             'name': 'swh-metadata-translator',
             'version': '0.0.1',
             'configuration': {"type": "local", "context": "npm"},
         }
-
-        tools = self.storage.tool_add([tool])
-        expected_tool = tools[0]
+        expected_tool = swh_storage.tool_add([tool])[0]
 
         # when
-        actual_tool = self.storage.tool_get(tool)
+        actual_tool = swh_storage.tool_get(tool)
 
         # then
-        self.assertEqual(expected_tool, actual_tool)
+        assert expected_tool == actual_tool
 
-    def test_metadata_provider_get(self):
+    def test_metadata_provider_get(self, swh_storage):
         # given
-        no_provider = self.storage.metadata_provider_get(6459456445615)
-        self.assertIsNone(no_provider)
+        no_provider = swh_storage.metadata_provider_get(6459456445615)
+        assert no_provider is None
         # when
-        provider_id = self.storage.metadata_provider_add(
-            self.provider['name'],
-            self.provider['type'],
-            self.provider['url'],
-            self.provider['metadata'])
+        provider_id = swh_storage.metadata_provider_add(
+            data.provider['name'],
+            data.provider['type'],
+            data.provider['url'],
+            data.provider['metadata'])
 
-        actual_provider = self.storage.metadata_provider_get(provider_id)
+        actual_provider = swh_storage.metadata_provider_get(provider_id)
         expected_provider = {
-            'provider_name': self.provider['name'],
-            'provider_url': self.provider['url']
+            'provider_name': data.provider['name'],
+            'provider_url': data.provider['url']
         }
         # then
         del actual_provider['id']
-        self.assertTrue(actual_provider, expected_provider)
+        assert actual_provider, expected_provider
 
-    def test_metadata_provider_get_by(self):
+    def test_metadata_provider_get_by(self, swh_storage):
         # given
-        no_provider = self.storage.metadata_provider_get_by({
-            'provider_name': self.provider['name'],
-            'provider_url': self.provider['url']
+        no_provider = swh_storage.metadata_provider_get_by({
+            'provider_name': data.provider['name'],
+            'provider_url': data.provider['url']
         })
-        self.assertIsNone(no_provider)
+        assert no_provider is None
         # when
-        provider_id = self.storage.metadata_provider_add(
-            self.provider['name'],
-            self.provider['type'],
-            self.provider['url'],
-            self.provider['metadata'])
-
-        actual_provider = self.storage.metadata_provider_get_by({
-            'provider_name': self.provider['name'],
-            'provider_url': self.provider['url']
+        provider_id = swh_storage.metadata_provider_add(
+            data.provider['name'],
+            data.provider['type'],
+            data.provider['url'],
+            data.provider['metadata'])
+
+        actual_provider = swh_storage.metadata_provider_get_by({
+            'provider_name': data.provider['name'],
+            'provider_url': data.provider['url']
         })
         # then
-        self.assertTrue(provider_id, actual_provider['id'])
+        assert provider_id, actual_provider['id']
+
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_origin_metadata_add(self, swh_storage, use_url):
+        if not self._test_origin_ids:
+            pytest.skip('requires origin id')
 
-    @given(strategies.booleans())
-    def test_origin_metadata_add(self, use_url):
-        self.reset_storage()
         # given
-        origin = self.storage.origin_add([self.origin])[0]
-        origin_id = origin['id']
-        if use_url:
-            origin = origin['url']
-        else:
-            origin = origin['id']
-        origin_metadata0 = list(self.storage.origin_metadata_get_by(
-            origin))
-        self.assertEqual(len(origin_metadata0), 0, origin_metadata0)
+        origin = swh_storage.origin_add([data.origin])[0]
 
-        tools = self.storage.tool_add([self.metadata_tool])
+        tools = swh_storage.tool_add([data.metadata_tool])
         tool = tools[0]
 
-        self.storage.metadata_provider_add(
-                           self.provider['name'],
-                           self.provider['type'],
-                           self.provider['url'],
-                           self.provider['metadata'])
-        provider = self.storage.metadata_provider_get_by({
-                            'provider_name': self.provider['name'],
-                            'provider_url': self.provider['url']
+        swh_storage.metadata_provider_add(
+                           data.provider['name'],
+                           data.provider['type'],
+                           data.provider['url'],
+                           data.provider['metadata'])
+        provider = swh_storage.metadata_provider_get_by({
+                            'provider_name': data.provider['name'],
+                            'provider_url': data.provider['url']
                       })
 
         # when adding for the same origin 2 metadatas
-        self.storage.origin_metadata_add(
+        origin = origin['url' if use_url else 'id']
+
+        n_om = len(list(swh_storage.origin_metadata_get_by(origin)))
+        swh_storage.origin_metadata_add(
                     origin,
-                    self.origin_metadata['discovery_date'],
+                    data.origin_metadata['discovery_date'],
                     provider['id'],
                     tool['id'],
-                    self.origin_metadata['metadata'])
-        self.storage.origin_metadata_add(
+                    data.origin_metadata['metadata'])
+        swh_storage.origin_metadata_add(
                     origin,
                     '2015-01-01 23:00:00+00',
                     provider['id'],
                     tool['id'],
-                    self.origin_metadata2['metadata'])
-        actual_om = list(self.storage.origin_metadata_get_by(
-            origin))
+                    data.origin_metadata2['metadata'])
+        n_actual_om = len(list(swh_storage.origin_metadata_get_by(origin)))
         # then
-        self.assertCountEqual(
-            [item['origin_id'] for item in actual_om],
-            [origin_id, origin_id])
+        assert n_actual_om == n_om + 2
+
+    def test_origin_metadata_get(self, swh_storage):
+        if not self._test_origin_ids:
+            pytest.skip('requires origin id')
 
-    def test_origin_metadata_get(self):
         # given
-        origin_id = self.storage.origin_add([self.origin])[0]['id']
-        origin_id2 = self.storage.origin_add([self.origin2])[0]['id']
-
-        self.storage.metadata_provider_add(self.provider['name'],
-                                           self.provider['type'],
-                                           self.provider['url'],
-                                           self.provider['metadata'])
-        provider = self.storage.metadata_provider_get_by({
-                            'provider_name': self.provider['name'],
-                            'provider_url': self.provider['url']
-                   })
-        tool = self.storage.tool_add([self.metadata_tool])[0]
+        origin_id = swh_storage.origin_add([data.origin])[0]['id']
+        origin_id2 = swh_storage.origin_add([data.origin2])[0]['id']
+
+        swh_storage.metadata_provider_add(data.provider['name'],
+                                          data.provider['type'],
+                                          data.provider['url'],
+                                          data.provider['metadata'])
+        provider = swh_storage.metadata_provider_get_by({
+            'provider_name': data.provider['name'],
+            'provider_url': data.provider['url']
+        })
+        tool = swh_storage.tool_add([data.metadata_tool])[0]
         # when adding for the same origin 2 metadatas
-        self.storage.origin_metadata_add(
+        swh_storage.origin_metadata_add(
                     origin_id,
-                    self.origin_metadata['discovery_date'],
+                    data.origin_metadata['discovery_date'],
                     provider['id'],
                     tool['id'],
-                    self.origin_metadata['metadata'])
-        self.storage.origin_metadata_add(
+                    data.origin_metadata['metadata'])
+        swh_storage.origin_metadata_add(
                     origin_id2,
-                    self.origin_metadata2['discovery_date'],
+                    data.origin_metadata2['discovery_date'],
                     provider['id'],
                     tool['id'],
-                    self.origin_metadata2['metadata'])
-        self.storage.origin_metadata_add(
+                    data.origin_metadata2['metadata'])
+        swh_storage.origin_metadata_add(
                     origin_id,
-                    self.origin_metadata2['discovery_date'],
+                    data.origin_metadata2['discovery_date'],
                     provider['id'],
                     tool['id'],
-                    self.origin_metadata2['metadata'])
-        all_metadatas = list(self.storage.origin_metadata_get_by(
-            origin_id))
-        metadatas_for_origin2 = list(self.storage.origin_metadata_get_by(
+                    data.origin_metadata2['metadata'])
+        all_metadatas = list(sorted(swh_storage.origin_metadata_get_by(
+            origin_id), key=lambda x: x['discovery_date']))
+        metadatas_for_origin2 = list(swh_storage.origin_metadata_get_by(
             origin_id2))
         expected_results = [{
             'origin_id': origin_id,
             'discovery_date': datetime.datetime(
-                                2017, 1, 1, 23, 0,
+                                2015, 1, 1, 23, 0,
                                 tzinfo=datetime.timezone.utc),
             'metadata': {
                 'name': 'test_origin_metadata',
                 'version': '0.0.1'
             },
             'provider_id': provider['id'],
             'provider_name': 'hal',
             'provider_type': 'deposit-client',
             'provider_url': 'http:///hal/inria',
             'tool_id': tool['id']
         }, {
             'origin_id': origin_id,
             'discovery_date': datetime.datetime(
-                                2015, 1, 1, 23, 0,
+                                2017, 1, 1, 23, 0,
                                 tzinfo=datetime.timezone.utc),
             'metadata': {
                 'name': 'test_origin_metadata',
                 'version': '0.0.1'
             },
             'provider_id': provider['id'],
             'provider_name': 'hal',
             'provider_type': 'deposit-client',
             'provider_url': 'http:///hal/inria',
             'tool_id': tool['id']
         }]
 
         # then
-        self.assertEqual(len(all_metadatas), 2)
-        self.assertEqual(len(metadatas_for_origin2), 1)
-        self.assertCountEqual(all_metadatas, expected_results)
+        assert len(all_metadatas) == 2
+        assert len(metadatas_for_origin2) == 1
+        assert all_metadatas == expected_results
 
-    def test_metadata_provider_add(self):
+    def test_metadata_provider_add(self, swh_storage):
         provider = {
             'provider_name': 'swMATH',
             'provider_type': 'registry',
             'provider_url': 'http://www.swmath.org/',
             'metadata': {
                 'email': 'contact@swmath.org',
                 'license': 'All rights reserved'
             }
         }
-        provider['id'] = provider_id = self.storage.metadata_provider_add(
+        provider['id'] = provider_id = swh_storage.metadata_provider_add(
             **provider)
-        self.assertEqual(
-            provider,
-            self.storage.metadata_provider_get_by({
-               'provider_name': 'swMATH',
-               'provider_url': 'http://www.swmath.org/'
-            }))
-        self.assertEqual(
-            provider,
-            self.storage.metadata_provider_get(provider_id))
-
-    def test_origin_metadata_get_by_provider_type(self):
+        assert provider == swh_storage.metadata_provider_get_by(
+            {'provider_name': 'swMATH',
+             'provider_url': 'http://www.swmath.org/'})
+        assert provider == swh_storage.metadata_provider_get(provider_id)
+
+    def test_origin_metadata_get_by_provider_type(self, swh_storage):
         # given
-        origin_id = self.storage.origin_add([self.origin])[0]['id']
-        origin_id2 = self.storage.origin_add([self.origin2])[0]['id']
-        provider1_id = self.storage.metadata_provider_add(
-                           self.provider['name'],
-                           self.provider['type'],
-                           self.provider['url'],
-                           self.provider['metadata'])
-        provider1 = self.storage.metadata_provider_get_by({
-                            'provider_name': self.provider['name'],
-                            'provider_url': self.provider['url']
+        if not self._test_origin_ids:
+            pytest.skip('reauires origin id')
+
+        origin_id = swh_storage.origin_add([data.origin])[0]['id']
+        origin_id2 = swh_storage.origin_add([data.origin2])[0]['id']
+        provider1_id = swh_storage.metadata_provider_add(
+                           data.provider['name'],
+                           data.provider['type'],
+                           data.provider['url'],
+                           data.provider['metadata'])
+        provider1 = swh_storage.metadata_provider_get_by({
+                            'provider_name': data.provider['name'],
+                            'provider_url': data.provider['url']
                    })
-        self.assertEqual(provider1,
-                         self.storage.metadata_provider_get(provider1_id))
+        assert provider1 == swh_storage.metadata_provider_get(provider1_id)
 
-        provider2_id = self.storage.metadata_provider_add(
+        provider2_id = swh_storage.metadata_provider_add(
                             'swMATH',
                             'registry',
                             'http://www.swmath.org/',
                             {'email': 'contact@swmath.org',
                              'license': 'All rights reserved'})
-        provider2 = self.storage.metadata_provider_get_by({
+        provider2 = swh_storage.metadata_provider_get_by({
                             'provider_name': 'swMATH',
                             'provider_url': 'http://www.swmath.org/'
                    })
-        self.assertEqual(provider2,
-                         self.storage.metadata_provider_get(provider2_id))
+        assert provider2 == swh_storage.metadata_provider_get(provider2_id)
 
         # using the only tool now inserted in the data.sql, but for this
         # provider should be a crawler tool (not yet implemented)
-        tool = self.storage.tool_add([self.metadata_tool])[0]
+        tool = swh_storage.tool_add([data.metadata_tool])[0]
 
         # when adding for the same origin 2 metadatas
-        self.storage.origin_metadata_add(
+        swh_storage.origin_metadata_add(
             origin_id,
-            self.origin_metadata['discovery_date'],
+            data.origin_metadata['discovery_date'],
             provider1['id'],
             tool['id'],
-            self.origin_metadata['metadata'])
-        self.storage.origin_metadata_add(
+            data.origin_metadata['metadata'])
+        swh_storage.origin_metadata_add(
             origin_id2,
-            self.origin_metadata2['discovery_date'],
+            data.origin_metadata2['discovery_date'],
             provider2['id'],
             tool['id'],
-            self.origin_metadata2['metadata'])
+            data.origin_metadata2['metadata'])
         provider_type = 'registry'
-        m_by_provider = list(self.storage.origin_metadata_get_by(
+        m_by_provider = list(swh_storage.origin_metadata_get_by(
             origin_id2,
             provider_type))
         for item in m_by_provider:
             if 'id' in item:
                 del item['id']
         expected_results = [{
             'origin_id': origin_id2,
             'discovery_date': datetime.datetime(
                                 2017, 1, 1, 23, 0,
                                 tzinfo=datetime.timezone.utc),
             'metadata': {
                 'name': 'test_origin_metadata',
                 'version': '0.0.1'
             },
             'provider_id': provider2['id'],
             'provider_name': 'swMATH',
             'provider_type': provider_type,
             'provider_url': 'http://www.swmath.org/',
             'tool_id': tool['id']
         }]
         # then
 
-        self.assertEqual(len(m_by_provider), 1)
-        self.assertEqual(m_by_provider, expected_results)
+        assert len(m_by_provider) == 1
+        assert m_by_provider == expected_results
 
 
-class CommonPropTestStorage:
+class TestStorageGeneratedData:
     _test_origin_ids = True
 
     def assert_contents_ok(self, expected_contents, actual_contents,
                            keys_to_check={'sha1', 'data'}):
         """Assert that a given list of contents matches on a given set of keys.
 
         """
         for k in keys_to_check:
-            expected_list = sorted([c[k] for c in expected_contents])
-            actual_list = sorted([c[k] for c in actual_contents])
-            self.assertEqual(actual_list, expected_list)
-
-    @given(gen_contents(min_size=1, max_size=4))
-    def test_generate_content_get(self, contents):
-        self.reset_storage()
-        # add contents to storage
-        self.storage.content_add(contents)
+            expected_list = set([c.get(k) for c in expected_contents])
+            actual_list = set([c.get(k) for c in actual_contents])
+            assert actual_list == expected_list, k
 
+    def test_generate_content_get(self, swh_storage, swh_contents):
+        contents_with_data = [c for c in swh_contents
+                              if c['status'] != 'absent']
         # input the list of sha1s we want from storage
-        get_sha1s = [c['sha1'] for c in contents]
+        get_sha1s = [c['sha1'] for c in contents_with_data]
 
         # retrieve contents
-        actual_contents = list(self.storage.content_get(get_sha1s))
-
-        self.assert_contents_ok(contents, actual_contents)
-
-    @given(gen_contents(min_size=1, max_size=4))
-    def test_generate_content_get_metadata(self, contents):
-        self.reset_storage()
-        # add contents to storage
-        self.storage.content_add(contents)
+        actual_contents = list(swh_storage.content_get(get_sha1s))
+        assert None not in actual_contents
+        self.assert_contents_ok(contents_with_data, actual_contents)
 
+    def test_generate_content_get_metadata(self, swh_storage, swh_contents):
         # input the list of sha1s we want from storage
-        get_sha1s = [c['sha1'] for c in contents]
+        expected_contents = [c for c in swh_contents
+                             if c['status'] != 'absent']
+        get_sha1s = [c['sha1'] for c in expected_contents]
 
         # retrieve contents
-        actual_contents = list(self.storage.content_get_metadata(get_sha1s))
+        actual_contents = list(swh_storage.content_get_metadata(get_sha1s))
 
-        self.assertEqual(len(actual_contents), len(contents))
+        assert len(actual_contents) == len(get_sha1s)
 
-        # will check that all contents are retrieved correctly
-        one_content = contents[0]
-        # content_get_metadata does not return data
-        keys_to_check = set(one_content.keys()) - {'data'}
-        self.assert_contents_ok(contents, actual_contents,
+        keys_to_check = {'length', 'status',
+                         'sha1', 'sha1_git', 'sha256', 'blake2s256'}
+        self.assert_contents_ok(expected_contents, actual_contents,
                                 keys_to_check=keys_to_check)
 
-    @given(gen_contents(),
-           strategies.binary(min_size=20, max_size=20),
-           strategies.binary(min_size=20, max_size=20))
-    def test_generate_content_get_range(self, contents, start, end):
+    def test_generate_content_get_range(self, swh_storage, swh_contents):
         """content_get_range paginates results if limit exceeded"""
-        self.reset_storage()
         # add contents to storage
-        self.storage.content_add(contents)
+        present_contents = [c for c in swh_contents
+                            if c['status'] != 'absent']
 
-        actual_result = self.storage.content_get_range(start, end)
+        get_sha1s = sorted([c['sha1'] for c in swh_contents
+                            if c['status'] != 'absent'])
+        start = get_sha1s[2]
+        end = get_sha1s[-2]
+        actual_result = swh_storage.content_get_range(start, end)
+
+        assert actual_result['next'] is None
 
         actual_contents = actual_result['contents']
-        actual_next = actual_result['next']
+        expected_contents = [c for c in present_contents
+                             if start <= c['sha1'] <= end]
+        if expected_contents:
+            self.assert_contents_ok(
+                expected_contents, actual_contents, ['sha1'])
+        else:
+            assert actual_contents == []
 
-        self.assertEqual(actual_next, None)
+    def test_generate_content_get_range_full(self, swh_storage, swh_contents):
+        """content_get_range for a full range returns all available contents"""
+        present_contents = [c for c in swh_contents
+                            if c['status'] != 'absent']
 
-        expected_contents = [c for c in contents
+        start = b'0' * 40
+        end = b'f' * 40
+        actual_result = swh_storage.content_get_range(start, end)
+        assert actual_result['next'] is None
+
+        actual_contents = actual_result['contents']
+        expected_contents = [c for c in present_contents
                              if start <= c['sha1'] <= end]
         if expected_contents:
-            keys_to_check = set(contents[0].keys()) - {'data'}
-            self.assert_contents_ok(expected_contents, actual_contents,
-                                    keys_to_check)
+            self.assert_contents_ok(
+                expected_contents, actual_contents, ['sha1'])
         else:
-            self.assertEqual(actual_contents, [])
+            assert actual_contents == []
 
-    def test_generate_content_get_range_limit_none(self):
+    def test_generate_content_get_range_empty(self, swh_storage, swh_contents):
+        """content_get_range for an empty range returns nothing"""
+        start = b'0' * 40
+        end = b'f' * 40
+        actual_result = swh_storage.content_get_range(end, start)
+        assert actual_result['next'] is None
+        assert len(actual_result['contents']) == 0
+
+    def test_generate_content_get_range_limit_none(self, swh_storage):
         """content_get_range call with wrong limit input should fail"""
-        with self.assertRaises(ValueError) as e:
-            self.storage.content_get_range(start=None, end=None, limit=None)
+        with pytest.raises(ValueError) as e:
+            swh_storage.content_get_range(start=None, end=None, limit=None)
 
-        self.assertEqual(e.exception.args, (
-            'Development error: limit should not be None',))
+        assert e.value.args == ('Development error: limit should not be None',)
 
-    @given(gen_contents(min_size=1, max_size=4))
-    def test_generate_content_get_range_no_limit(self, contents):
+    def test_generate_content_get_range_no_limit(
+            self, swh_storage, swh_contents):
         """content_get_range returns contents within range provided"""
-        self.reset_storage()
         # add contents to storage
-        self.storage.content_add(contents)
-
         # input the list of sha1s we want from storage
-        get_sha1s = sorted([c['sha1'] for c in contents])
+        get_sha1s = sorted([c['sha1'] for c in swh_contents
+                            if c['status'] != 'absent'])
         start = get_sha1s[0]
         end = get_sha1s[-1]
 
         # retrieve contents
-        actual_result = self.storage.content_get_range(start, end)
+        actual_result = swh_storage.content_get_range(start, end)
 
         actual_contents = actual_result['contents']
-        actual_next = actual_result['next']
+        assert actual_result['next'] is None
+        assert len(actual_contents) == len(get_sha1s)
 
-        self.assertEqual(len(contents), len(actual_contents))
-        self.assertIsNone(actual_next)
+        expected_contents = [c for c in swh_contents
+                             if c['status'] != 'absent']
+        self.assert_contents_ok(
+            expected_contents, actual_contents, ['sha1'])
 
-        one_content = contents[0]
-        keys_to_check = set(one_content.keys()) - {'data'}
-        self.assert_contents_ok(contents, actual_contents, keys_to_check)
-
-    @given(gen_contents(min_size=4, max_size=4))
-    def test_generate_content_get_range_limit(self, contents):
+    def test_generate_content_get_range_limit(self, swh_storage, swh_contents):
         """content_get_range paginates results if limit exceeded"""
-        self.reset_storage()
-        contents_map = {c['sha1']: c for c in contents}
-
-        # add contents to storage
-        self.storage.content_add(contents)
+        contents_map = {c['sha1']: c for c in swh_contents}
 
         # input the list of sha1s we want from storage
-        get_sha1s = sorted([c['sha1'] for c in contents])
+        get_sha1s = sorted([c['sha1'] for c in swh_contents
+                            if c['status'] != 'absent'])
         start = get_sha1s[0]
         end = get_sha1s[-1]
 
-        # retrieve contents limited to 3 results
-        limited_results = len(contents) - 1
-        actual_result = self.storage.content_get_range(start, end,
-                                                       limit=limited_results)
+        # retrieve contents limited to n-1 results
+        limited_results = len(get_sha1s) - 1
+        actual_result = swh_storage.content_get_range(
+            start, end, limit=limited_results)
 
         actual_contents = actual_result['contents']
-        actual_next = actual_result['next']
-
-        self.assertEqual(limited_results, len(actual_contents))
-        self.assertIsNotNone(actual_next)
-        self.assertEqual(actual_next, get_sha1s[-1])
+        assert actual_result['next'] == get_sha1s[-1]
+        assert len(actual_contents) == limited_results
 
         expected_contents = [contents_map[sha1] for sha1 in get_sha1s[:-1]]
-        keys_to_check = set(contents[0].keys()) - {'data'}
-        self.assert_contents_ok(expected_contents, actual_contents,
-                                keys_to_check)
+        self.assert_contents_ok(
+            expected_contents, actual_contents, ['sha1'])
 
         # retrieve next part
-        actual_results2 = self.storage.content_get_range(start=end, end=end)
+        actual_results2 = swh_storage.content_get_range(start=end, end=end)
+        assert actual_results2['next'] is None
         actual_contents2 = actual_results2['contents']
-        actual_next2 = actual_results2['next']
+        assert len(actual_contents2) == 1
 
-        self.assertEqual(1, len(actual_contents2))
-        self.assertIsNone(actual_next2)
+        self.assert_contents_ok(
+            [contents_map[get_sha1s[-1]]], actual_contents2, ['sha1'])
 
-        self.assert_contents_ok([contents_map[actual_next]], actual_contents2,
-
-                                keys_to_check)
-
-    def test_origin_get_invalid_id_legacy(self):
+    def test_origin_get_invalid_id_legacy(self, swh_storage):
         if self._test_origin_ids:
             invalid_origin_id = 1
-            origin_info = self.storage.origin_get({'id': invalid_origin_id})
-            self.assertIsNone(origin_info)
+            origin_info = swh_storage.origin_get({'id': invalid_origin_id})
+            assert origin_info is None
 
-            origin_visits = list(self.storage.origin_visit_get(
+            origin_visits = list(swh_storage.origin_visit_get(
                 invalid_origin_id))
-            self.assertEqual(origin_visits, [])
+            assert origin_visits == []
 
-    def test_origin_get_invalid_id(self):
+    def test_origin_get_invalid_id(self, swh_storage):
         if self._test_origin_ids:
-            origin_info = self.storage.origin_get([{'id': 1}, {'id': 2}])
-            self.assertEqual(origin_info, [None, None])
+            origin_info = swh_storage.origin_get([{'id': 1}, {'id': 2}])
+            assert origin_info == [None, None]
 
-            origin_visits = list(self.storage.origin_visit_get(1))
-            self.assertEqual(origin_visits, [])
+            origin_visits = list(swh_storage.origin_visit_get(1))
+            assert origin_visits == []
 
-    @given(strategies.lists(origins().map(lambda x: x.to_dict()),
-                            unique_by=lambda x: x['url'],
-                            min_size=6, max_size=15))
-    def test_origin_get_range(self, new_origins):
-        self.reset_storage()
-        nb_origins = len(new_origins)
+    def test_origin_get_range(self, swh_storage, swh_origins):
+        if not self._test_origin_ids:
+            pytest.skip('requires origin id')
+
+        actual_origins = list(
+            swh_storage.origin_get_range(origin_from=0,
+                                         origin_count=0))
+        assert len(actual_origins) == 0
 
-        self.storage.origin_add(new_origins)
+        actual_origins = list(
+            swh_storage.origin_get_range(origin_from=0,
+                                         origin_count=1))
+        assert len(actual_origins) == 1
+        assert actual_origins[0]['id'] == 1
 
-        origin_from = random.randint(1, nb_origins-1)
-        origin_count = random.randint(1, nb_origins - origin_from)
+        actual_origins = list(
+            swh_storage.origin_get_range(origin_from=1,
+                                         origin_count=1))
+        assert len(actual_origins) == 1
+        assert actual_origins[0]['id'] == 1
 
         actual_origins = list(
-            self.storage.origin_get_range(origin_from=origin_from,
-                                          origin_count=origin_count))
+            swh_storage.origin_get_range(origin_from=1,
+                                         origin_count=10))
+        assert len(actual_origins) == 10
+        assert actual_origins[0]['id'] == 1
+        assert actual_origins[-1]['id'] == 10
 
-        for origin in actual_origins:
-            del origin['id']
+        actual_origins = list(
+            swh_storage.origin_get_range(origin_from=1,
+                                         origin_count=20))
+        assert len(actual_origins) == 20
+        assert actual_origins[0]['id'] == 1
+        assert actual_origins[-1]['id'] == 20
 
-        for origin in actual_origins:
-            self.assertIn(origin, new_origins)
+        actual_origins = list(
+            swh_storage.origin_get_range(origin_from=1,
+                                         origin_count=21))
+        assert len(actual_origins) == 20
+        assert actual_origins[0]['id'] == 1
+        assert actual_origins[-1]['id'] == 20
 
-        origin_from = -1
-        origin_count = 5
-        origins = list(
-            self.storage.origin_get_range(origin_from=origin_from,
-                                          origin_count=origin_count))
-        self.assertEqual(len(origins), origin_count)
+        actual_origins = list(
+            swh_storage.origin_get_range(origin_from=11,
+                                         origin_count=0))
+        assert len(actual_origins) == 0
 
-        origin_from = 10000
-        origins = list(
-            self.storage.origin_get_range(origin_from=origin_from,
-                                          origin_count=origin_count))
-        self.assertEqual(len(origins), 0)
+        actual_origins = list(
+            swh_storage.origin_get_range(origin_from=11,
+                                         origin_count=10))
+        assert len(actual_origins) == 10
+        assert actual_origins[0]['id'] == 11
+        assert actual_origins[-1]['id'] == 20
 
-    def test_origin_count(self):
+        actual_origins = list(
+            swh_storage.origin_get_range(origin_from=11,
+                                         origin_count=11))
+        assert len(actual_origins) == 10
+        assert actual_origins[0]['id'] == 11
+        assert actual_origins[-1]['id'] == 20
 
+    def test_origin_count(self, swh_storage):
         new_origins = [
             {
                 'type': 'git',
                 'url': 'https://github.com/user1/repo1'
             },
             {
                 'type': 'git',
                 'url': 'https://github.com/user2/repo1'
             },
             {
                 'type': 'git',
                 'url': 'https://github.com/user3/repo1'
             },
             {
                 'type': 'git',
                 'url': 'https://gitlab.com/user1/repo1'
             },
             {
                 'type': 'git',
                 'url': 'https://gitlab.com/user2/repo1'
             }
         ]
 
-        self.storage.origin_add(new_origins)
+        swh_storage.origin_add(new_origins)
 
-        self.assertEqual(self.storage.origin_count('github'), 3)
-        self.assertEqual(self.storage.origin_count('gitlab'), 2)
-        self.assertEqual(
-            self.storage.origin_count('.*user.*', regexp=True), 5)
-        self.assertEqual(
-            self.storage.origin_count('.*user.*', regexp=False), 0)
-        self.assertEqual(
-            self.storage.origin_count('.*user1.*', regexp=True), 2)
-        self.assertEqual(
-            self.storage.origin_count('.*user1.*', regexp=False), 0)
+        assert swh_storage.origin_count('github') == 3
+        assert swh_storage.origin_count('gitlab') == 2
+        assert swh_storage.origin_count('.*user.*', regexp=True) == 5
+        assert swh_storage.origin_count('.*user.*', regexp=False) == 0
+        assert swh_storage.origin_count('.*user1.*', regexp=True) == 2
+        assert swh_storage.origin_count('.*user1.*', regexp=False) == 0
 
     @settings(suppress_health_check=[HealthCheck.too_slow])
     @given(strategies.lists(objects(), max_size=2))
-    def test_add_arbitrary(self, objects):
-        self.reset_storage()
+    def test_add_arbitrary(self, swh_storage, objects):
         for (obj_type, obj) in objects:
             obj = obj.to_dict()
             if obj_type == 'origin_visit':
-                origin_id = self.storage.origin_add_one(obj.pop('origin'))
+                origin_id = swh_storage.origin_add_one(obj.pop('origin'))
                 if 'visit' in obj:
                     del obj['visit']
-                self.storage.origin_visit_add(
+                swh_storage.origin_visit_add(
                     origin_id, obj['date'], obj['type'])
             else:
-                method = getattr(self.storage, obj_type + '_add')
+                method = getattr(swh_storage, obj_type + '_add')
                 try:
                     method([obj])
                 except HashCollision:
                     pass
 
 
 @pytest.mark.db
-class TestLocalStorage(CommonTestStorage, StorageTestDbFixture,
-                       unittest.TestCase):
+class TestLocalStorage:
     """Test the local storage"""
+    _test_origin_ids = True
 
     # Can only be tested with local storage as you can't mock
     # datetimes for the remote server
-    @given(strategies.booleans())
-    def test_fetch_history(self, use_url):
+    @pytest.mark.parametrize('use_url', [True, False])
+    def test_fetch_history(self, swh_storage, use_url):
         if not self._test_origin_ids and not use_url:
             return
-        self.reset_storage()
 
-        origin_id = self.storage.origin_add_one(self.origin)
-        origin_id_or_url = self.origin['url'] if use_url else origin_id
+        origin_id = swh_storage.origin_add_one(data.origin)
+        origin_id_or_url = data.origin['url'] if use_url else origin_id
         with patch('datetime.datetime'):
-            datetime.datetime.now.return_value = self.fetch_history_date
-            fetch_history_id = self.storage.fetch_history_start(
+            datetime.datetime.now.return_value = data.fetch_history_date
+            fetch_history_id = swh_storage.fetch_history_start(
                 origin_id_or_url)
             datetime.datetime.now.assert_called_with(tz=datetime.timezone.utc)
 
         with patch('datetime.datetime'):
-            datetime.datetime.now.return_value = self.fetch_history_end
-            self.storage.fetch_history_end(fetch_history_id,
-                                           self.fetch_history_data)
+            datetime.datetime.now.return_value = data.fetch_history_end
+            swh_storage.fetch_history_end(fetch_history_id,
+                                          data.fetch_history_data)
 
-        fetch_history = self.storage.fetch_history_get(fetch_history_id)
-        expected_fetch_history = self.fetch_history_data.copy()
+        fetch_history = swh_storage.fetch_history_get(fetch_history_id)
+        expected_fetch_history = data.fetch_history_data.copy()
 
         expected_fetch_history['id'] = fetch_history_id
         expected_fetch_history['origin'] = origin_id
-        expected_fetch_history['date'] = self.fetch_history_date
-        expected_fetch_history['duration'] = self.fetch_history_duration
+        expected_fetch_history['date'] = data.fetch_history_date
+        expected_fetch_history['duration'] = data.fetch_history_duration
 
-        self.assertEqual(expected_fetch_history, fetch_history)
+        assert expected_fetch_history == fetch_history
 
     # This test is only relevant on the local storage, with an actual
     # objstorage raising an exception
-    def test_content_add_objstorage_exception(self):
-        self.storage.objstorage.add = Mock(
+    def test_content_add_objstorage_exception(self, swh_storage):
+        swh_storage.objstorage.add = Mock(
             side_effect=Exception('mocked broken objstorage')
         )
 
-        with self.assertRaises(Exception) as e:
-            self.storage.content_add([self.cont])
+        with pytest.raises(Exception) as e:
+            swh_storage.content_add([data.cont])
 
-        self.assertEqual(e.exception.args, ('mocked broken objstorage',))
-        missing = list(self.storage.content_missing([self.cont]))
-        self.assertEqual(missing, [self.cont['sha1']])
+        assert e.value.args == ('mocked broken objstorage',)
+        missing = list(swh_storage.content_missing([data.cont]))
+        assert missing == [data.cont['sha1']]
 
 
 @pytest.mark.db
-class TestStorageRaceConditions(TestStorageData, StorageTestDbFixture,
-                                unittest.TestCase):
+class TestStorageRaceConditions:
     @pytest.mark.xfail
-    def test_content_add_race(self):
+    def test_content_add_race(self, swh_storage):
 
         results = queue.Queue()
 
         def thread():
             try:
-                with self.db_transaction() as (db, cur):
-                    ret = self.storage.content_add([self.cont], db=db,
-                                                   cur=cur)
+                with db_transaction(swh_storage) as (db, cur):
+                    ret = swh_storage.content_add([data.cont], db=db,
+                                                  cur=cur)
                 results.put((threading.get_ident(), 'data', ret))
             except Exception as e:
                 results.put((threading.get_ident(), 'exc', e))
 
         t1 = threading.Thread(target=thread)
         t2 = threading.Thread(target=thread)
         t1.start()
         # this avoids the race condition
         # import time
         # time.sleep(1)
         t2.start()
         t1.join()
         t2.join()
 
         r1 = results.get(block=False)
         r2 = results.get(block=False)
 
         with pytest.raises(queue.Empty):
             results.get(block=False)
         assert r1[0] != r2[0]
         assert r1[1] == 'data', 'Got exception %r in Thread%s' % (r1[2], r1[0])
         assert r2[1] == 'data', 'Got exception %r in Thread%s' % (r2[2], r2[0])
 
 
 @pytest.mark.db
-@pytest.mark.property_based
-class PropTestLocalStorage(CommonPropTestStorage, StorageTestDbFixture,
-                           unittest.TestCase):
-    pass
-
-
-class AlteringSchemaTest(TestStorageData, StorageTestDbFixture,
-                         unittest.TestCase):
+class TestPgStorage:
     """This class is dedicated for the rare case where the schema needs to
        be altered dynamically.
 
        Otherwise, the tests could be blocking when ran altogether.
 
     """
-    def test_content_update(self):
-        self.storage.journal_writer = None  # TODO, not supported
+    def test_content_update(self, swh_storage):
+        swh_storage.journal_writer = None  # TODO, not supported
 
-        cont = copy.deepcopy(self.cont)
+        cont = copy.deepcopy(data.cont)
 
-        self.storage.content_add([cont])
+        swh_storage.content_add([cont])
         # alter the sha1_git for example
         cont['sha1_git'] = hash_to_bytes(
             '3a60a5275d0333bf13468e8b3dcab90f4046e654')
 
-        self.storage.content_update([cont], keys=['sha1_git'])
+        swh_storage.content_update([cont], keys=['sha1_git'])
 
-        with self.db_transaction() as (_, cur):
+        with db_transaction(swh_storage) as (_, cur):
             cur.execute('SELECT sha1, sha1_git, sha256, length, status'
                         ' FROM content WHERE sha1 = %s',
                         (cont['sha1'],))
             datum = cur.fetchone()
 
-        self.assertEqual(
-            (datum[0], datum[1], datum[2],
-             datum[3], datum[4]),
-            (cont['sha1'], cont['sha1_git'], cont['sha256'],
-             cont['length'], 'visible'))
+        assert datum == (cont['sha1'], cont['sha1_git'], cont['sha256'],
+                         cont['length'], 'visible')
 
-    def test_content_update_with_new_cols(self):
-        self.storage.journal_writer = None  # TODO, not supported
+    def test_content_update_with_new_cols(self, swh_storage):
+        swh_storage.journal_writer = None  # TODO, not supported
 
-        with self.db_transaction() as (db, cur):
+        with db_transaction(swh_storage) as (_, cur):
             cur.execute("""alter table content
                            add column test text default null,
                            add column test2 text default null""")
 
-        cont = copy.deepcopy(self.cont2)
-        self.storage.content_add([cont])
+        cont = copy.deepcopy(data.cont2)
+        swh_storage.content_add([cont])
         cont['test'] = 'value-1'
         cont['test2'] = 'value-2'
 
-        self.storage.content_update([cont], keys=['test', 'test2'])
-        with self.db_transaction() as (_, cur):
+        swh_storage.content_update([cont], keys=['test', 'test2'])
+        with db_transaction(swh_storage) as (_, cur):
             cur.execute(
                 '''SELECT sha1, sha1_git, sha256, length, status,
                    test, test2
                    FROM content WHERE sha1 = %s''',
                 (cont['sha1'],))
 
             datum = cur.fetchone()
 
-        self.assertEqual(
-            (datum[0], datum[1], datum[2],
-             datum[3], datum[4], datum[5], datum[6]),
-            (cont['sha1'], cont['sha1_git'], cont['sha256'],
-             cont['length'], 'visible', cont['test'], cont['test2']))
+        assert datum == (cont['sha1'], cont['sha1_git'], cont['sha256'],
+                         cont['length'], 'visible',
+                         cont['test'], cont['test2'])
 
-        with self.db_transaction() as (_, cur):
+        with db_transaction(swh_storage) as (_, cur):
             cur.execute("""alter table content drop column test,
                                                drop column test2""")
+
+    def test_content_add_db(self, swh_storage):
+        cont = data.cont
+
+        actual_result = swh_storage.content_add([cont])
+
+        assert actual_result == {
+            'content:add': 1,
+            'content:add:bytes': cont['length'],
+            'skipped_content:add': 0
+            }
+
+        if hasattr(swh_storage, 'objstorage'):
+            assert cont['sha1'] in swh_storage.objstorage
+
+        with db_transaction(swh_storage) as (_, cur):
+            cur.execute('SELECT sha1, sha1_git, sha256, length, status'
+                        ' FROM content WHERE sha1 = %s',
+                        (cont['sha1'],))
+            datum = cur.fetchone()
+
+        assert datum == (cont['sha1'], cont['sha1_git'], cont['sha256'],
+                         cont['length'], 'visible')
+
+        expected_cont = cont.copy()
+        del expected_cont['data']
+        journal_objects = list(swh_storage.journal_writer.objects)
+        for (obj_type, obj) in journal_objects:
+            del obj['ctime']
+        assert journal_objects == [('content', expected_cont)]
+
+    def test_content_add_metadata_db(self, swh_storage):
+        cont = data.cont
+        del cont['data']
+        cont['ctime'] = datetime.datetime.now()
+
+        actual_result = swh_storage.content_add_metadata([cont])
+
+        assert actual_result == {
+            'content:add': 1,
+            'skipped_content:add': 0
+            }
+
+        if hasattr(swh_storage, 'objstorage'):
+            assert cont['sha1'] not in swh_storage.objstorage
+        with db_transaction(swh_storage) as (_, cur):
+            cur.execute('SELECT sha1, sha1_git, sha256, length, status'
+                        ' FROM content WHERE sha1 = %s',
+                        (cont['sha1'],))
+            datum = cur.fetchone()
+        assert datum == (cont['sha1'], cont['sha1_git'], cont['sha256'],
+                         cont['length'], 'visible')
+
+        assert list(swh_storage.journal_writer.objects) == [('content', cont)]
+
+    def test_skipped_content_add_db(self, swh_storage):
+        cont = data.skipped_cont
+        cont2 = data.skipped_cont2
+        cont2['blake2s256'] = None
+
+        actual_result = swh_storage.content_add([cont, cont, cont2])
+
+        assert actual_result == {
+            'content:add': 0,
+            'content:add:bytes': 0,
+            'skipped_content:add': 2,
+            }
+
+        with db_transaction(swh_storage) as (_, cur):
+            cur.execute('SELECT sha1, sha1_git, sha256, blake2s256, '
+                        'length, status, reason '
+                        'FROM skipped_content ORDER BY sha1_git')
+
+            dbdata = cur.fetchall()
+
+        assert len(dbdata) == 2
+        assert dbdata[0] == (cont['sha1'], cont['sha1_git'], cont['sha256'],
+                             cont['blake2s256'], cont['length'], 'absent',
+                             'Content too long')
+
+        assert dbdata[1] == (cont2['sha1'], cont2['sha1_git'], cont2['sha256'],
+                             cont2['blake2s256'], cont2['length'], 'absent',
+                             'Content too long')
diff --git a/version.txt b/version.txt
index f49843c1..0303a19e 100644
--- a/version.txt
+++ b/version.txt
@@ -1 +1 @@
-v0.0.152-0-g03d5a2c
\ No newline at end of file
+v0.0.153-0-g3bb46f6
\ No newline at end of file