diff --git a/swh/storage/storage.py b/swh/storage/storage.py
index 9e965bea..8bf34378 100644
--- a/swh/storage/storage.py
+++ b/swh/storage/storage.py
@@ -1,1318 +1,1322 @@
 # Copyright (C) 2015-2020  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 contextlib
 import datetime
 import itertools
 
 from collections import defaultdict
 from contextlib import contextmanager
 from typing import (
     Any,
     Counter,
     Dict,
     Iterable,
     List,
     Optional,
     Tuple,
     Union,
 )
 
 import attr
 import psycopg2
 import psycopg2.pool
 import psycopg2.errors
 
 from swh.core.api.serializers import msgpack_loads, msgpack_dumps
 from swh.model.identifiers import parse_swhid, SWHID
 from swh.model.model import (
     Content,
     Directory,
     Origin,
     OriginVisit,
     OriginVisitStatus,
     Revision,
     Release,
     SkippedContent,
     Snapshot,
     SHA1_SIZE,
     MetadataAuthority,
     MetadataAuthorityType,
     MetadataFetcher,
     MetadataTargetType,
     RawExtrinsicMetadata,
 )
 from swh.model.hashutil import DEFAULT_ALGORITHMS, hash_to_bytes, hash_to_hex
 from swh.storage.objstorage import ObjStorage
 from swh.storage.utils import now
 
 from . import converters
 from .common import db_transaction_generator, db_transaction
 from .db import Db
 from .exc import StorageArgumentException, StorageDBError, HashCollision
 from .algos import diff
 from .metrics import timed, send_metric, process_metrics
 from .utils import get_partition_bounds_bytes, extract_collision_hash, map_optional
 from .writer import JournalWriter
 
 
 # Max block size of contents to return
 BULK_BLOCK_CONTENT_LEN_MAX = 10000
 
 EMPTY_SNAPSHOT_ID = hash_to_bytes("1a8893e6a86f444e8be8e7bda6cb34fb1735a00e")
 """Identifier for the empty snapshot"""
 
 
 VALIDATION_EXCEPTIONS = (
     KeyError,
     TypeError,
     ValueError,
     psycopg2.errors.CheckViolation,
     psycopg2.errors.IntegrityError,
     psycopg2.errors.InvalidTextRepresentation,
     psycopg2.errors.NotNullViolation,
     psycopg2.errors.NumericValueOutOfRange,
     psycopg2.errors.UndefinedFunction,  # (raised on wrong argument typs)
 )
 """Exceptions raised by postgresql when validation of the arguments
 failed."""
 
 
 @contextlib.contextmanager
 def convert_validation_exceptions():
     """Catches postgresql errors related to invalid arguments, and
     re-raises a StorageArgumentException."""
     try:
         yield
     except tuple(VALIDATION_EXCEPTIONS) as e:
         raise StorageArgumentException(str(e))
 
 
 class Storage:
     """SWH storage proxy, encompassing DB and object storage
 
     """
 
     def __init__(
         self, db, objstorage, min_pool_conns=1, max_pool_conns=10, journal_writer=None
     ):
         """
         Args:
             db_conn: either a libpq connection string, or a psycopg2 connection
             obj_root: path to the root of the object storage
 
         """
         try:
             if isinstance(db, psycopg2.extensions.connection):
                 self._pool = None
                 self._db = Db(db)
             else:
                 self._pool = psycopg2.pool.ThreadedConnectionPool(
                     min_pool_conns, max_pool_conns, db
                 )
                 self._db = None
         except psycopg2.OperationalError as e:
             raise StorageDBError(e)
 
         self.journal_writer = JournalWriter(journal_writer)
         self.objstorage = ObjStorage(objstorage)
 
     def get_db(self):
         if self._db:
             return self._db
         else:
             return Db.from_pool(self._pool)
 
     def put_db(self, db):
         if db is not self._db:
             db.put_conn()
 
     @contextmanager
     def db(self):
         db = None
         try:
             db = self.get_db()
             yield db
         finally:
             if db:
                 self.put_db(db)
 
     @timed
     @db_transaction()
     def check_config(self, *, check_write, db=None, cur=None):
 
         if not self.objstorage.check_config(check_write=check_write):
             return False
 
         # Check permissions on one of the tables
         if check_write:
             check = "INSERT"
         else:
             check = "SELECT"
 
         cur.execute("select has_table_privilege(current_user, 'content', %s)", (check,))
         return cur.fetchone()[0]
 
     def _content_unique_key(self, hash, db):
         """Given a hash (tuple or dict), return a unique key from the
            aggregation of keys.
 
         """
         keys = db.content_hash_keys
         if isinstance(hash, tuple):
             return hash
         return tuple([hash[k] for k in keys])
 
     def _content_add_metadata(self, db, cur, content):
         """Add content to the postgresql database but not the object storage.
         """
         # create temporary table for metadata injection
         db.mktemp("content", cur)
 
         db.copy_to(
             (c.to_dict() for c in content), "tmp_content", db.content_add_keys, cur
         )
 
         # move metadata in place
         try:
             db.content_add_from_temp(cur)
         except psycopg2.IntegrityError as e:
             if e.diag.sqlstate == "23505" and e.diag.table_name == "content":
                 message_detail = e.diag.message_detail
                 if message_detail:
                     hash_name, hash_id = extract_collision_hash(message_detail)
                     collision_contents_hashes = [
                         c.hashes() for c in content if c.get_hash(hash_name) == hash_id
                     ]
                 else:
                     constraint_to_hash_name = {
                         "content_pkey": "sha1",
                         "content_sha1_git_idx": "sha1_git",
                         "content_sha256_idx": "sha256",
                     }
                     hash_name = constraint_to_hash_name.get(e.diag.constraint_name)
                     hash_id = None
                     collision_contents_hashes = None
 
                 raise HashCollision(
                     hash_name, hash_id, collision_contents_hashes
                 ) from None
             else:
                 raise
 
     @timed
     @process_metrics
     def content_add(self, content: Iterable[Content]) -> Dict:
         ctime = now()
 
         contents = [attr.evolve(c, ctime=ctime) for c in content]
 
         objstorage_summary = self.objstorage.content_add(contents)
 
         with self.db() as db:
             with db.transaction() as cur:
                 missing = list(
                     self.content_missing(
                         map(Content.to_dict, contents),
                         key_hash="sha1_git",
                         db=db,
                         cur=cur,
                     )
                 )
                 contents = [c for c in contents if c.sha1_git in missing]
 
                 self.journal_writer.content_add(contents)
                 self._content_add_metadata(db, cur, contents)
 
         return {
             "content:add": len(contents),
             "content:add:bytes": objstorage_summary["content:add:bytes"],
         }
 
     @timed
     @db_transaction()
     def content_update(self, content, keys=[], db=None, cur=None):
         # TODO: Add a check on input keys. How to properly implement
         # this? We don't know yet the new columns.
         self.journal_writer.content_update(content)
 
         db.mktemp("content", cur)
         select_keys = list(set(db.content_get_metadata_keys).union(set(keys)))
         with convert_validation_exceptions():
             db.copy_to(content, "tmp_content", select_keys, cur)
             db.content_update_from_temp(keys_to_update=keys, cur=cur)
 
     @timed
     @process_metrics
     @db_transaction()
     def content_add_metadata(
         self, content: Iterable[Content], db=None, cur=None
     ) -> Dict:
         contents = list(content)
         missing = self.content_missing(
             (c.to_dict() for c in contents), key_hash="sha1_git", db=db, cur=cur,
         )
         contents = [c for c in contents if c.sha1_git in missing]
 
         self.journal_writer.content_add_metadata(contents)
         self._content_add_metadata(db, cur, contents)
 
         return {
             "content:add": len(contents),
         }
 
     @timed
     def content_get(self, content):
         # FIXME: Make this method support slicing the `data`.
         if len(content) > BULK_BLOCK_CONTENT_LEN_MAX:
             raise StorageArgumentException(
                 "Send at maximum %s contents." % BULK_BLOCK_CONTENT_LEN_MAX
             )
         yield from self.objstorage.content_get(content)
 
     @timed
     @db_transaction()
     def content_get_range(self, start, end, limit=1000, db=None, cur=None):
         if limit is None:
             raise StorageArgumentException("limit should not be None")
         contents = []
         next_content = None
         for counter, content_row in enumerate(
             db.content_get_range(start, end, limit + 1, cur)
         ):
             content = dict(zip(db.content_get_metadata_keys, content_row))
             if counter >= limit:
                 # take the last commit for the next page starting from this
                 next_content = content["sha1"]
                 break
             contents.append(content)
         return {
             "contents": contents,
             "next": next_content,
         }
 
     @timed
     def content_get_partition(
         self,
         partition_id: int,
         nb_partitions: int,
         limit: int = 1000,
         page_token: str = None,
     ):
         if limit is None:
             raise StorageArgumentException("limit should not be None")
         (start, end) = get_partition_bounds_bytes(
             partition_id, nb_partitions, SHA1_SIZE
         )
         if page_token:
             start = hash_to_bytes(page_token)
         if end is None:
             end = b"\xff" * SHA1_SIZE
         result = self.content_get_range(start, end, limit)
         result2 = {
             "contents": result["contents"],
             "next_page_token": None,
         }
         if result["next"]:
             result2["next_page_token"] = hash_to_hex(result["next"])
         return result2
 
     @timed
     @db_transaction(statement_timeout=500)
     def content_get_metadata(
         self, contents: List[bytes], db=None, cur=None
     ) -> Dict[bytes, List[Dict]]:
         result: Dict[bytes, List[Dict]] = {sha1: [] for sha1 in contents}
         for row in db.content_get_metadata_from_sha1s(contents, cur):
             content_meta = dict(zip(db.content_get_metadata_keys, row))
             result[content_meta["sha1"]].append(content_meta)
         return result
 
     @timed
     @db_transaction_generator()
     def content_missing(self, content, key_hash="sha1", db=None, cur=None):
         keys = db.content_hash_keys
 
         if key_hash not in keys:
             raise StorageArgumentException("key_hash should be one of %s" % keys)
 
         key_hash_idx = keys.index(key_hash)
 
         if not content:
             return
 
         for obj in db.content_missing_from_list(content, cur):
             yield obj[key_hash_idx]
 
     @timed
     @db_transaction_generator()
     def content_missing_per_sha1(self, contents, db=None, cur=None):
         for obj in db.content_missing_per_sha1(contents, cur):
             yield obj[0]
 
     @timed
     @db_transaction_generator()
     def content_missing_per_sha1_git(self, contents, db=None, cur=None):
         for obj in db.content_missing_per_sha1_git(contents, cur):
             yield obj[0]
 
     @timed
     @db_transaction()
     def content_find(self, content, db=None, cur=None):
         if not set(content).intersection(DEFAULT_ALGORITHMS):
             raise StorageArgumentException(
                 "content keys must contain at least one of: "
                 "sha1, sha1_git, sha256, blake2s256"
             )
 
         contents = db.content_find(
             sha1=content.get("sha1"),
             sha1_git=content.get("sha1_git"),
             sha256=content.get("sha256"),
             blake2s256=content.get("blake2s256"),
             cur=cur,
         )
         return [dict(zip(db.content_find_cols, content)) for content in contents]
 
     @timed
     @db_transaction()
     def content_get_random(self, db=None, cur=None):
         return db.content_get_random(cur)
 
     @staticmethod
     def _skipped_content_normalize(d):
         d = d.copy()
 
         if d.get("status") is None:
             d["status"] = "absent"
 
         if d.get("length") is None:
             d["length"] = -1
 
         return d
 
     def _skipped_content_add_metadata(self, db, cur, content: Iterable[SkippedContent]):
         origin_ids = db.origin_id_get_by_url([cont.origin for cont in content], cur=cur)
         content = [
             attr.evolve(c, origin=origin_id)
             for (c, origin_id) in zip(content, origin_ids)
         ]
         db.mktemp("skipped_content", cur)
         db.copy_to(
             [c.to_dict() for c in content],
             "tmp_skipped_content",
             db.skipped_content_keys,
             cur,
         )
 
         # move metadata in place
         db.skipped_content_add_from_temp(cur)
 
     @timed
     @process_metrics
     @db_transaction()
     def skipped_content_add(
         self, content: Iterable[SkippedContent], db=None, cur=None
     ) -> Dict:
         ctime = now()
         content = [attr.evolve(c, ctime=ctime) for c in content]
 
         missing_contents = self.skipped_content_missing(
             (c.to_dict() for c in content), db=db, cur=cur,
         )
         content = [
             c
             for c in content
             if any(
                 all(
                     c.get_hash(algo) == missing_content.get(algo)
                     for algo in DEFAULT_ALGORITHMS
                 )
                 for missing_content in missing_contents
             )
         ]
 
         self.journal_writer.skipped_content_add(content)
         self._skipped_content_add_metadata(db, cur, content)
 
         return {
             "skipped_content:add": len(content),
         }
 
     @timed
     @db_transaction_generator()
     def skipped_content_missing(self, contents, db=None, cur=None):
         contents = list(contents)
         for content in db.skipped_content_missing(contents, cur):
             yield dict(zip(db.content_hash_keys, content))
 
     @timed
     @process_metrics
     @db_transaction()
     def directory_add(
         self, directories: Iterable[Directory], db=None, cur=None
     ) -> Dict:
         directories = list(directories)
         summary = {"directory:add": 0}
 
         dirs = set()
         dir_entries: Dict[str, defaultdict] = {
             "file": defaultdict(list),
             "dir": defaultdict(list),
             "rev": defaultdict(list),
         }
 
         for cur_dir in directories:
             dir_id = cur_dir.id
             dirs.add(dir_id)
             for src_entry in cur_dir.entries:
                 entry = src_entry.to_dict()
                 entry["dir_id"] = dir_id
                 dir_entries[entry["type"]][dir_id].append(entry)
 
         dirs_missing = set(self.directory_missing(dirs, db=db, cur=cur))
         if not dirs_missing:
             return summary
 
         self.journal_writer.directory_add(
             dir_ for dir_ in directories if dir_.id in dirs_missing
         )
 
         # Copy directory ids
         dirs_missing_dict = ({"id": dir} for dir in dirs_missing)
         db.mktemp("directory", cur)
         db.copy_to(dirs_missing_dict, "tmp_directory", ["id"], cur)
 
         # Copy entries
         for entry_type, entry_list in dir_entries.items():
             entries = itertools.chain.from_iterable(
                 entries_for_dir
                 for dir_id, entries_for_dir in entry_list.items()
                 if dir_id in dirs_missing
             )
 
             db.mktemp_dir_entry(entry_type)
 
             db.copy_to(
                 entries,
                 "tmp_directory_entry_%s" % entry_type,
                 ["target", "name", "perms", "dir_id"],
                 cur,
             )
 
         # Do the final copy
         db.directory_add_from_temp(cur)
         summary["directory:add"] = len(dirs_missing)
 
         return summary
 
     @timed
     @db_transaction_generator()
     def directory_missing(self, directories, db=None, cur=None):
         for obj in db.directory_missing_from_list(directories, cur):
             yield obj[0]
 
     @timed
     @db_transaction_generator(statement_timeout=20000)
     def directory_ls(self, directory, recursive=False, db=None, cur=None):
         if recursive:
             res_gen = db.directory_walk(directory, cur=cur)
         else:
             res_gen = db.directory_walk_one(directory, cur=cur)
 
         for line in res_gen:
             yield dict(zip(db.directory_ls_cols, line))
 
     @timed
     @db_transaction(statement_timeout=2000)
     def directory_entry_get_by_path(self, directory, paths, db=None, cur=None):
         res = db.directory_entry_get_by_path(directory, paths, cur)
         if res:
             return dict(zip(db.directory_ls_cols, res))
 
     @timed
     @db_transaction()
     def directory_get_random(self, db=None, cur=None):
         return db.directory_get_random(cur)
 
     @timed
     @process_metrics
     @db_transaction()
     def revision_add(self, revisions: Iterable[Revision], db=None, cur=None) -> Dict:
         revisions = list(revisions)
         summary = {"revision:add": 0}
 
         revisions_missing = set(
             self.revision_missing(
                 set(revision.id for revision in revisions), db=db, cur=cur
             )
         )
 
         if not revisions_missing:
             return summary
 
         db.mktemp_revision(cur)
 
         revisions_filtered = [
             revision for revision in revisions if revision.id in revisions_missing
         ]
 
         self.journal_writer.revision_add(revisions_filtered)
 
         revisions_filtered = list(map(converters.revision_to_db, revisions_filtered))
 
         parents_filtered: List[bytes] = []
 
         with convert_validation_exceptions():
             db.copy_to(
                 revisions_filtered,
                 "tmp_revision",
                 db.revision_add_cols,
                 cur,
                 lambda rev: parents_filtered.extend(rev["parents"]),
             )
 
             db.revision_add_from_temp(cur)
 
             db.copy_to(
                 parents_filtered,
                 "revision_history",
                 ["id", "parent_id", "parent_rank"],
                 cur,
             )
 
         return {"revision:add": len(revisions_missing)}
 
     @timed
     @db_transaction_generator()
     def revision_missing(self, revisions, db=None, cur=None):
         if not revisions:
             return
 
         for obj in db.revision_missing_from_list(revisions, cur):
             yield obj[0]
 
     @timed
     @db_transaction_generator(statement_timeout=1000)
     def revision_get(self, revisions, db=None, cur=None):
         for line in db.revision_get_from_list(revisions, cur):
             data = converters.db_to_revision(dict(zip(db.revision_get_cols, line)))
             if not data["type"]:
                 yield None
                 continue
             yield data
 
     @timed
     @db_transaction_generator(statement_timeout=2000)
     def revision_log(self, revisions, limit=None, db=None, cur=None):
         for line in db.revision_log(revisions, limit, cur):
             data = converters.db_to_revision(dict(zip(db.revision_get_cols, line)))
             if not data["type"]:
                 yield None
                 continue
             yield data
 
     @timed
     @db_transaction_generator(statement_timeout=2000)
     def revision_shortlog(self, revisions, limit=None, db=None, cur=None):
 
         yield from db.revision_shortlog(revisions, limit, cur)
 
     @timed
     @db_transaction()
     def revision_get_random(self, db=None, cur=None):
         return db.revision_get_random(cur)
 
     @timed
     @process_metrics
     @db_transaction()
     def release_add(self, releases: Iterable[Release], db=None, cur=None) -> Dict:
         releases = list(releases)
         summary = {"release:add": 0}
 
         release_ids = set(release.id for release in releases)
         releases_missing = set(self.release_missing(release_ids, db=db, cur=cur))
 
         if not releases_missing:
             return summary
 
         db.mktemp_release(cur)
 
         releases_filtered = [
             release for release in releases if release.id in releases_missing
         ]
 
         self.journal_writer.release_add(releases_filtered)
 
         releases_filtered = list(map(converters.release_to_db, releases_filtered))
 
         with convert_validation_exceptions():
             db.copy_to(releases_filtered, "tmp_release", db.release_add_cols, cur)
 
             db.release_add_from_temp(cur)
 
         return {"release:add": len(releases_missing)}
 
     @timed
     @db_transaction_generator()
     def release_missing(self, releases, db=None, cur=None):
         if not releases:
             return
 
         for obj in db.release_missing_from_list(releases, cur):
             yield obj[0]
 
     @timed
     @db_transaction_generator(statement_timeout=500)
     def release_get(self, releases, db=None, cur=None):
         for release in db.release_get_from_list(releases, cur):
             data = converters.db_to_release(dict(zip(db.release_get_cols, release)))
             yield data if data["target_type"] else None
 
     @timed
     @db_transaction()
     def release_get_random(self, db=None, cur=None):
         return db.release_get_random(cur)
 
     @timed
     @process_metrics
     @db_transaction()
     def snapshot_add(self, snapshots: Iterable[Snapshot], db=None, cur=None) -> Dict:
         created_temp_table = False
 
         count = 0
         for snapshot in snapshots:
             if not db.snapshot_exists(snapshot.id, cur):
                 if not created_temp_table:
                     db.mktemp_snapshot_branch(cur)
                     created_temp_table = True
 
                 with convert_validation_exceptions():
                     db.copy_to(
                         (
                             {
                                 "name": name,
                                 "target": info.target if info else None,
                                 "target_type": (
                                     info.target_type.value if info else None
                                 ),
                             }
                             for name, info in snapshot.branches.items()
                         ),
                         "tmp_snapshot_branch",
                         ["name", "target", "target_type"],
                         cur,
                     )
 
                 self.journal_writer.snapshot_add([snapshot])
 
                 db.snapshot_add(snapshot.id, cur)
                 count += 1
 
         return {"snapshot:add": count}
 
     @timed
     @db_transaction_generator()
     def snapshot_missing(self, snapshots, db=None, cur=None):
         for obj in db.snapshot_missing_from_list(snapshots, cur):
             yield obj[0]
 
     @timed
     @db_transaction(statement_timeout=2000)
     def snapshot_get(self, snapshot_id, db=None, cur=None):
 
         return self.snapshot_get_branches(snapshot_id, db=db, cur=cur)
 
     @timed
     @db_transaction(statement_timeout=2000)
     def snapshot_get_by_origin_visit(self, origin, visit, db=None, cur=None):
         snapshot_id = db.snapshot_get_by_origin_visit(origin, visit, cur)
 
         if snapshot_id:
             return self.snapshot_get(snapshot_id, db=db, cur=cur)
 
         return None
 
     @timed
     @db_transaction(statement_timeout=2000)
     def snapshot_count_branches(self, snapshot_id, db=None, cur=None):
         return dict([bc for bc in db.snapshot_count_branches(snapshot_id, cur)])
 
     @timed
     @db_transaction(statement_timeout=2000)
     def snapshot_get_branches(
         self,
         snapshot_id,
         branches_from=b"",
         branches_count=1000,
         target_types=None,
         db=None,
         cur=None,
     ):
         if snapshot_id == EMPTY_SNAPSHOT_ID:
             return {
                 "id": snapshot_id,
                 "branches": {},
                 "next_branch": None,
             }
 
         branches = {}
         next_branch = None
 
         fetched_branches = list(
             db.snapshot_get_by_id(
                 snapshot_id,
                 branches_from=branches_from,
                 branches_count=branches_count + 1,
                 target_types=target_types,
                 cur=cur,
             )
         )
         for branch in fetched_branches[:branches_count]:
             branch = dict(zip(db.snapshot_get_cols, branch))
             del branch["snapshot_id"]
             name = branch.pop("name")
             if branch == {"target": None, "target_type": None}:
                 branch = None
             branches[name] = branch
 
         if len(fetched_branches) > branches_count:
             branch = dict(zip(db.snapshot_get_cols, fetched_branches[-1]))
             next_branch = branch["name"]
 
         if branches:
             return {
                 "id": snapshot_id,
                 "branches": branches,
                 "next_branch": next_branch,
             }
 
         return None
 
     @timed
     @db_transaction()
     def snapshot_get_random(self, db=None, cur=None):
         return db.snapshot_get_random(cur)
 
     @timed
     @db_transaction()
     def origin_visit_add(
         self, visits: Iterable[OriginVisit], db=None, cur=None
     ) -> Iterable[OriginVisit]:
         for visit in visits:
             origin = self.origin_get([visit.origin], db=db, cur=cur)[0]
             if not origin:  # Cannot add a visit without an origin
                 raise StorageArgumentException("Unknown origin %s", visit.origin)
 
         all_visits = []
         nb_visits = 0
         for visit in visits:
             nb_visits += 1
             if not visit.visit:
                 with convert_validation_exceptions():
                     visit_id = db.origin_visit_add(
                         visit.origin, visit.date, visit.type, cur=cur
                     )
                 visit = attr.evolve(visit, visit=visit_id)
             else:
                 db.origin_visit_add_with_id(visit, cur=cur)
             assert visit.visit is not None
             all_visits.append(visit)
             # Forced to write after for the case when the visit has no id
             self.journal_writer.origin_visit_add([visit])
             visit_status = OriginVisitStatus(
                 origin=visit.origin,
                 visit=visit.visit,
                 date=visit.date,
                 status="created",
                 snapshot=None,
             )
             self._origin_visit_status_add(visit_status, db=db, cur=cur)
 
         send_metric("origin_visit:add", count=nb_visits, method_name="origin_visit")
         return all_visits
 
     def _origin_visit_status_add(
         self, visit_status: OriginVisitStatus, db, cur
     ) -> None:
         """Add an origin visit status"""
         self.journal_writer.origin_visit_status_add([visit_status])
         db.origin_visit_status_add(visit_status, cur=cur)
         send_metric(
             "origin_visit_status:add", count=1, method_name="origin_visit_status"
         )
 
     @timed
     @db_transaction()
     def origin_visit_status_add(
         self, visit_statuses: Iterable[OriginVisitStatus], db=None, cur=None,
     ) -> None:
         # First round to check existence (fail early if any is ko)
         for visit_status in visit_statuses:
             origin_url = self.origin_get([visit_status.origin], db=db, cur=cur)[0]
             if not origin_url:
                 raise StorageArgumentException(f"Unknown origin {visit_status.origin}")
 
         for visit_status in visit_statuses:
             self._origin_visit_status_add(visit_status, db, cur)
 
     @timed
     @db_transaction()
     def origin_visit_status_get_latest(
         self,
         origin_url: str,
         visit: int,
         allowed_statuses: Optional[List[str]] = None,
         require_snapshot: bool = False,
         db=None,
         cur=None,
     ) -> Optional[OriginVisitStatus]:
         row = db.origin_visit_status_get_latest(
             origin_url, visit, allowed_statuses, require_snapshot, cur=cur
         )
         if not row:
             return None
         return OriginVisitStatus.from_dict(row)
 
     @timed
     @db_transaction_generator(statement_timeout=500)
     def origin_visit_get(
         self,
         origin: str,
         last_visit: Optional[int] = None,
         limit: Optional[int] = None,
         order: str = "asc",
         db=None,
         cur=None,
     ) -> Iterable[Dict[str, Any]]:
         assert order in ["asc", "desc"]
         lines = db.origin_visit_get_all(
             origin, last_visit=last_visit, limit=limit, order=order, cur=cur
         )
         for line in lines:
             yield dict(zip(db.origin_visit_get_cols, line))
 
     @timed
     @db_transaction(statement_timeout=500)
     def origin_visit_find_by_date(
         self, origin: str, visit_date: datetime.datetime, db=None, cur=None
     ) -> Optional[Dict[str, Any]]:
         return db.origin_visit_find_by_date(origin, visit_date, cur=cur)
 
     @timed
     @db_transaction(statement_timeout=500)
     def origin_visit_get_by(
         self, origin: str, visit: int, db=None, cur=None
     ) -> Optional[Dict[str, Any]]:
         row = db.origin_visit_get(origin, visit, cur)
         if row:
             return dict(zip(db.origin_visit_get_cols, row))
         return None
 
     @timed
     @db_transaction(statement_timeout=4000)
     def origin_visit_get_latest(
         self,
         origin: str,
         type: Optional[str] = None,
         allowed_statuses: Optional[List[str]] = None,
         require_snapshot: bool = False,
         db=None,
         cur=None,
     ) -> Optional[Dict[str, Any]]:
         row = db.origin_visit_get_latest(
             origin,
             type=type,
             allowed_statuses=allowed_statuses,
             require_snapshot=require_snapshot,
             cur=cur,
         )
         if row:
             return dict(zip(db.origin_visit_get_cols, row))
         return None
 
     @timed
     @db_transaction()
     def origin_visit_status_get_random(
         self, type: str, db=None, cur=None
     ) -> Optional[Tuple[OriginVisit, OriginVisitStatus]]:
         row = db.origin_visit_get_random(type, cur)
         if row is not None:
             row_d = dict(zip(db.origin_visit_get_cols, row))
             visit = OriginVisit(
                 origin=row_d["origin"],
                 visit=row_d["visit"],
                 date=row_d["date"],
                 type=row_d["type"],
             )
             visit_status = OriginVisitStatus(
                 origin=row_d["origin"],
                 visit=row_d["visit"],
                 date=row_d["date"],
                 status=row_d["status"],
                 metadata=row_d["metadata"],
                 snapshot=row_d["snapshot"],
             )
             return visit, visit_status
         return None
 
     @timed
     @db_transaction(statement_timeout=2000)
     def object_find_by_sha1_git(self, ids, db=None, cur=None):
         ret = {id: [] for id in ids}
 
         for retval in db.object_find_by_sha1_git(ids, cur=cur):
             if retval[1]:
                 ret[retval[0]].append(
                     dict(zip(db.object_find_by_sha1_git_cols, retval))
                 )
 
         return ret
 
     @timed
     @db_transaction(statement_timeout=500)
     def origin_get(
         self, origins: Iterable[str], db=None, cur=None
     ) -> Iterable[Optional[Origin]]:
         origin_urls = list(origins)
         rows = db.origin_get_by_url(origin_urls, cur)
         result: List[Optional[Origin]] = []
         for row in rows:
             origin_d = dict(zip(db.origin_cols, row))
             url = origin_d["url"]
             result.append(None if url is None else Origin(url=url))
         return result
 
     @timed
     @db_transaction_generator(statement_timeout=500)
     def origin_get_by_sha1(self, sha1s, db=None, cur=None):
         for line in db.origin_get_by_sha1(sha1s, cur):
             if line[0] is not None:
                 yield dict(zip(db.origin_cols, line))
             else:
                 yield None
 
     @timed
     @db_transaction_generator()
     def origin_get_range(self, origin_from=1, origin_count=100, db=None, cur=None):
         for origin in db.origin_get_range(origin_from, origin_count, cur):
             yield dict(zip(db.origin_get_range_cols, origin))
 
     @timed
     @db_transaction()
     def origin_list(
         self, page_token: Optional[str] = None, limit: int = 100, *, db=None, cur=None
     ) -> dict:
         page_token = page_token or "0"
         if not isinstance(page_token, str):
             raise StorageArgumentException("page_token must be a string.")
         origin_from = int(page_token)
         result: Dict[str, Any] = {
             "origins": [
                 dict(zip(db.origin_get_range_cols, origin))
                 for origin in db.origin_get_range(origin_from, limit, cur)
             ],
         }
 
         assert len(result["origins"]) <= limit
         if len(result["origins"]) == limit:
             result["next_page_token"] = str(result["origins"][limit - 1]["id"] + 1)
 
         for origin in result["origins"]:
             del origin["id"]
 
         return result
 
     @timed
     @db_transaction_generator()
     def origin_search(
         self,
         url_pattern,
         offset=0,
         limit=50,
         regexp=False,
         with_visit=False,
         db=None,
         cur=None,
     ):
         for origin in db.origin_search(
             url_pattern, offset, limit, regexp, with_visit, cur
         ):
             yield dict(zip(db.origin_cols, origin))
 
     @timed
     @db_transaction()
     def origin_count(
         self, url_pattern, regexp=False, with_visit=False, db=None, cur=None
     ):
         return db.origin_count(url_pattern, regexp, with_visit, cur)
 
     @timed
     @process_metrics
     @db_transaction()
     def origin_add(
         self, origins: Iterable[Origin], db=None, cur=None
     ) -> Dict[str, int]:
         urls = [o.url for o in origins]
         known_origins = set(url for (url,) in db.origin_get_by_url(urls, cur))
         # use lists here to keep origins sorted; some tests depend on this
         to_add = [url for url in urls if url not in known_origins]
 
         self.journal_writer.origin_add([Origin(url=url) for url in to_add])
         added = 0
         for url in to_add:
             if db.origin_add(url, cur):
                 added += 1
         return {"origin:add": added}
 
     @db_transaction(statement_timeout=500)
     def stat_counters(self, db=None, cur=None):
         return {k: v for (k, v) in db.stat_counters()}
 
     @db_transaction()
     def refresh_stat_counters(self, db=None, cur=None):
         keys = [
             "content",
             "directory",
             "directory_entry_dir",
             "directory_entry_file",
             "directory_entry_rev",
             "origin",
             "origin_visit",
             "person",
             "release",
             "revision",
             "revision_history",
             "skipped_content",
             "snapshot",
         ]
 
         for key in keys:
             cur.execute("select * from swh_update_counter(%s)", (key,))
 
     @db_transaction()
     def object_metadata_add(
         self, metadata: Iterable[RawExtrinsicMetadata], db, cur,
     ) -> None:
         counter = Counter[MetadataTargetType]()
         for metadata_entry in metadata:
             authority_id = self._get_authority_id(metadata_entry.authority, db, cur)
             fetcher_id = self._get_fetcher_id(metadata_entry.fetcher, db, cur)
 
             db.object_metadata_add(
                 object_type=metadata_entry.type.value,
                 id=str(metadata_entry.id),
                 discovery_date=metadata_entry.discovery_date,
                 authority_id=authority_id,
                 fetcher_id=fetcher_id,
                 format=metadata_entry.format,
                 metadata=metadata_entry.metadata,
                 origin=metadata_entry.origin,
                 visit=metadata_entry.visit,
                 snapshot=map_optional(str, metadata_entry.snapshot),
                 release=map_optional(str, metadata_entry.release),
                 revision=map_optional(str, metadata_entry.revision),
                 path=metadata_entry.path,
                 directory=map_optional(str, metadata_entry.directory),
                 cur=cur,
             )
             counter[metadata_entry.type] += 1
 
         for (object_type, count) in counter.items():
             send_metric(
                 f"{object_type.value}_metadata:add",
                 count=count,
                 method_name=f"{object_type.value}_metadata_add",
             )
 
     @db_transaction()
     def object_metadata_get(
         self,
         object_type: MetadataTargetType,
         id: Union[str, SWHID],
         authority: MetadataAuthority,
         after: Optional[datetime.datetime] = None,
         page_token: Optional[bytes] = None,
         limit: int = 1000,
         db=None,
         cur=None,
     ) -> Dict[str, Union[Optional[bytes], List[RawExtrinsicMetadata]]]:
         if object_type == MetadataTargetType.ORIGIN:
             if isinstance(id, SWHID):
                 raise StorageArgumentException(
                     f"object_metadata_get called with object_type='origin', but "
                     f"provided id is an SWHID: {id!r}"
                 )
         else:
             if not isinstance(id, SWHID):
                 raise StorageArgumentException(
                     f"object_metadata_get called with object_type!='origin', but "
                     f"provided id is not an SWHID: {id!r}"
                 )
 
         if page_token:
             (after_time, after_fetcher) = msgpack_loads(page_token)
             if after and after_time < after:
                 raise StorageArgumentException(
                     "page_token is inconsistent with the value of 'after'."
                 )
         else:
             after_time = after
             after_fetcher = None
 
         authority_id = self._get_authority_id(authority, db, cur)
         if not authority_id:
             return {
                 "next_page_token": None,
                 "results": [],
             }
 
         rows = db.object_metadata_get(
             object_type,
             str(id),
             authority_id,
             after_time,
             after_fetcher,
             limit + 1,
             cur,
         )
         rows = [dict(zip(db.object_metadata_get_cols, row)) for row in rows]
         results = []
         for row in rows:
             row = row.copy()
             row.pop("metadata_fetcher.id")
 
             assert str(id) == row["object_metadata.id"]
 
             result = RawExtrinsicMetadata(
                 type=MetadataTargetType(row["object_metadata.type"]),
                 id=id,
                 authority=MetadataAuthority(
                     type=MetadataAuthorityType(row["metadata_authority.type"]),
                     url=row["metadata_authority.url"],
                 ),
                 fetcher=MetadataFetcher(
                     name=row["metadata_fetcher.name"],
                     version=row["metadata_fetcher.version"],
                 ),
                 discovery_date=row["discovery_date"],
                 format=row["format"],
                 metadata=row["object_metadata.metadata"],
                 origin=row["origin"],
                 visit=row["visit"],
                 snapshot=map_optional(parse_swhid, row["snapshot"]),
                 release=map_optional(parse_swhid, row["release"]),
                 revision=map_optional(parse_swhid, row["revision"]),
                 path=row["path"],
                 directory=map_optional(parse_swhid, row["directory"]),
             )
 
             results.append(result)
 
         if len(results) > limit:
             results.pop()
             assert len(results) == limit
             last_returned_row = rows[-2]  # rows[-1] corresponds to the popped result
             next_page_token: Optional[bytes] = msgpack_dumps(
                 (
                     last_returned_row["discovery_date"],
                     last_returned_row["metadata_fetcher.id"],
                 )
             )
         else:
             next_page_token = None
 
         return {
             "next_page_token": next_page_token,
             "results": results,
         }
 
     @timed
     @db_transaction()
     def metadata_fetcher_add(
         self, fetchers: Iterable[MetadataFetcher], db=None, cur=None
     ) -> None:
-        for (i, fetcher) in enumerate(fetchers):
+        count = 0
+        for fetcher in fetchers:
             if fetcher.metadata is None:
                 raise StorageArgumentException(
                     "MetadataFetcher.metadata may not be None in metadata_fetcher_add."
                 )
             db.metadata_fetcher_add(
                 fetcher.name, fetcher.version, dict(fetcher.metadata), cur=cur
             )
-        send_metric("metadata_fetcher:add", count=i + 1, method_name="metadata_fetcher")
+            count += 1
+        send_metric("metadata_fetcher:add", count=count, method_name="metadata_fetcher")
 
     @timed
     @db_transaction(statement_timeout=500)
     def metadata_fetcher_get(
         self, name: str, version: str, db=None, cur=None
     ) -> Optional[MetadataFetcher]:
         row = db.metadata_fetcher_get(name, version, cur=cur)
         if not row:
             return None
         return MetadataFetcher.from_dict(dict(zip(db.metadata_fetcher_cols, row)))
 
     @timed
     @db_transaction()
     def metadata_authority_add(
         self, authorities: Iterable[MetadataAuthority], db=None, cur=None
     ) -> None:
-        for (i, authority) in enumerate(authorities):
+        count = 0
+        for authority in authorities:
             if authority.metadata is None:
                 raise StorageArgumentException(
                     "MetadataAuthority.metadata may not be None in "
                     "metadata_authority_add."
                 )
             db.metadata_authority_add(
                 authority.type.value, authority.url, dict(authority.metadata), cur=cur
             )
+            count += 1
         send_metric(
-            "metadata_authority:add", count=i + 1, method_name="metadata_authority"
+            "metadata_authority:add", count=count, method_name="metadata_authority"
         )
 
     @timed
     @db_transaction()
     def metadata_authority_get(
         self, type: MetadataAuthorityType, url: str, db=None, cur=None
     ) -> Optional[MetadataAuthority]:
         row = db.metadata_authority_get(type.value, url, cur=cur)
         if not row:
             return None
         return MetadataAuthority.from_dict(dict(zip(db.metadata_authority_cols, row)))
 
     @timed
     def diff_directories(self, from_dir, to_dir, track_renaming=False):
         return diff.diff_directories(self, from_dir, to_dir, track_renaming)
 
     @timed
     def diff_revisions(self, from_rev, to_rev, track_renaming=False):
         return diff.diff_revisions(self, from_rev, to_rev, track_renaming)
 
     @timed
     def diff_revision(self, revision, track_renaming=False):
         return diff.diff_revision(self, revision, track_renaming)
 
     def clear_buffers(self, object_types: Optional[Iterable[str]] = None) -> None:
         """Do nothing
 
         """
         return None
 
     def flush(self, object_types: Optional[Iterable[str]] = None) -> Dict:
         return {}
 
     def _get_authority_id(self, authority: MetadataAuthority, db, cur):
         authority_id = db.metadata_authority_get_id(
             authority.type.value, authority.url, cur
         )
         if not authority_id:
             raise StorageArgumentException(f"Unknown authority {authority}")
         return authority_id
 
     def _get_fetcher_id(self, fetcher: MetadataFetcher, db, cur):
         fetcher_id = db.metadata_fetcher_get_id(fetcher.name, fetcher.version, cur)
         if not fetcher_id:
             raise StorageArgumentException(f"Unknown fetcher {fetcher}")
         return fetcher_id
diff --git a/swh/storage/tests/test_storage.py b/swh/storage/tests/test_storage.py
index f5c10514..ccbc1eff 100644
--- a/swh/storage/tests/test_storage.py
+++ b/swh/storage/tests/test_storage.py
@@ -1,4155 +1,4172 @@
 # Copyright (C) 2015-2020  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
 import inspect
 import itertools
 import math
 import queue
 import random
 import threading
 
 from collections import defaultdict
 from contextlib import contextmanager
 from datetime import timedelta
 from unittest.mock import Mock
 
 import attr
 import pytest
 
 from hypothesis import given, strategies, settings, HealthCheck
 
 from typing import ClassVar, Optional
 
 from swh.model import from_disk
 from swh.model.hashutil import hash_to_bytes
 from swh.model.identifiers import SWHID
 from swh.model.model import (
     Content,
     MetadataTargetType,
     Origin,
     OriginVisit,
     OriginVisitStatus,
     Person,
     Release,
     Revision,
     Snapshot,
 )
 from swh.model.hypothesis_strategies import objects
 from swh.storage import get_storage
 from swh.storage.converters import origin_url_to_sha1 as sha1
 from swh.storage.exc import HashCollision, StorageArgumentException
 from swh.storage.interface import StorageInterface
 from swh.storage.utils import content_hex_hashes, now
 
 
 @contextmanager
 def db_transaction(storage):
     with storage.db() as db:
         with db.transaction() as cur:
             yield db, cur
 
 
 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,
         }
 
 
 def cmpdir(directory):
     return (directory["type"], directory["dir_id"])
 
 
 def assert_contents_ok(
     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 = 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 round_to_milliseconds(date):
     """Round datetime to milliseconds before insertion, so equality doesn't fail after a
     round-trip through a DB (eg. Cassandra)
 
     """
     return date.replace(microsecond=(date.microsecond // 1000) * 1000)
 
 
 def test_round_to_milliseconds():
     date = now()
 
     for (ms, expected_ms) in [(0, 0), (1000, 1000), (555555, 555000), (999500, 999000)]:
         date = date.replace(microsecond=ms)
         actual_date = round_to_milliseconds(date)
         assert actual_date.microsecond == expected_ms
 
 
 class LazyContent(Content):
     def with_data(self):
         return Content.from_dict({**self.to_dict(), "data": b"42\n"})
 
 
 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]]
 
     def test_types(self, swh_storage_backend_config):
         """Checks all methods of StorageInterface are implemented by this
         backend, and that they have the same signature."""
         # Create an instance of the protocol (which cannot be instantiated
         # directly, so this creates a subclass, then instantiates it)
         interface = type("_", (StorageInterface,), {})()
         storage = get_storage(**swh_storage_backend_config)
 
         assert "content_add" in dir(interface)
 
         missing_methods = []
 
         for meth_name in dir(interface):
             if meth_name.startswith("_"):
                 continue
             interface_meth = getattr(interface, meth_name)
             try:
                 concrete_meth = getattr(storage, meth_name)
             except AttributeError:
                 if not getattr(interface_meth, "deprecated_endpoint", False):
                     # The backend is missing a (non-deprecated) endpoint
                     missing_methods.append(meth_name)
                 continue
 
             expected_signature = inspect.signature(interface_meth)
             actual_signature = inspect.signature(concrete_meth)
 
             assert expected_signature == actual_signature, meth_name
 
         assert missing_methods == []
 
     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_content_add(self, swh_storage, sample_data):
         cont = sample_data.content
 
         insertion_start_time = now()
         actual_result = swh_storage.content_add([cont])
         insertion_end_time = now()
 
         assert actual_result == {
             "content:add": 1,
             "content:add:bytes": cont.length,
         }
 
         assert list(swh_storage.content_get([cont.sha1])) == [
             {"sha1": cont.sha1, "data": cont.data}
         ]
 
         expected_cont = attr.evolve(cont, data=None)
 
         contents = [
             obj
             for (obj_type, obj) in swh_storage.journal_writer.journal.objects
             if obj_type == "content"
         ]
         assert len(contents) == 1
         for obj in contents:
             assert insertion_start_time <= obj.ctime
             assert obj.ctime <= insertion_end_time
             assert obj == expected_cont
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["content"] == 1
 
     def test_content_add_from_generator(self, swh_storage, sample_data):
         cont = sample_data.content
 
         def _cnt_gen():
             yield cont
 
         actual_result = swh_storage.content_add(_cnt_gen())
 
         assert actual_result == {
             "content:add": 1,
             "content:add:bytes": cont.length,
         }
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["content"] == 1
 
     def test_content_add_from_lazy_content(self, swh_storage, sample_data):
         cont = sample_data.content
         lazy_content = LazyContent.from_dict(cont.to_dict())
 
         insertion_start_time = now()
 
         actual_result = swh_storage.content_add([lazy_content])
 
         insertion_end_time = now()
 
         assert actual_result == {
             "content:add": 1,
             "content:add:bytes": cont.length,
         }
 
         # the fact that we retrieve the content object from the storage with
         # the correct 'data' field ensures it has been 'called'
         assert list(swh_storage.content_get([cont.sha1])) == [
             {"sha1": cont.sha1, "data": cont.data}
         ]
 
         expected_cont = attr.evolve(lazy_content, data=None, ctime=None)
         contents = [
             obj
             for (obj_type, obj) in swh_storage.journal_writer.journal.objects
             if obj_type == "content"
         ]
         assert len(contents) == 1
         for obj in contents:
             assert insertion_start_time <= obj.ctime
             assert obj.ctime <= insertion_end_time
             assert attr.evolve(obj, ctime=None).to_dict() == expected_cont.to_dict()
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["content"] == 1
 
     def test_content_get_missing(self, swh_storage, sample_data):
         cont, cont2 = sample_data.contents[:2]
 
         swh_storage.content_add([cont])
 
         # Query a single missing content
         results = list(swh_storage.content_get([cont2.sha1]))
         assert results == [None]
 
         # Check content_get does not abort after finding a missing content
         results = list(swh_storage.content_get([cont.sha1, 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(swh_storage.content_get([cont2.sha1, cont.sha1]))
         assert results == [None, {"sha1": cont.sha1, "data": cont.data}]
 
     def test_content_add_different_input(self, swh_storage, sample_data):
         cont, cont2 = sample_data.contents[:2]
 
         actual_result = swh_storage.content_add([cont, cont2])
         assert actual_result == {
             "content:add": 2,
             "content:add:bytes": cont.length + cont2.length,
         }
 
     def test_content_add_twice(self, swh_storage, sample_data):
         cont, cont2 = sample_data.contents[:2]
 
         actual_result = swh_storage.content_add([cont])
         assert actual_result == {
             "content:add": 1,
             "content:add:bytes": cont.length,
         }
         assert len(swh_storage.journal_writer.journal.objects) == 1
 
         actual_result = swh_storage.content_add([cont, cont2])
         assert actual_result == {
             "content:add": 1,
             "content:add:bytes": cont2.length,
         }
         assert 2 <= len(swh_storage.journal_writer.journal.objects) <= 3
 
         assert len(swh_storage.content_find(cont.to_dict())) == 1
         assert len(swh_storage.content_find(cont2.to_dict())) == 1
 
     def test_content_add_collision(self, swh_storage, sample_data):
         cont1 = sample_data.content
 
         # create (corrupted) content with same sha1{,_git} but != sha256
         sha256_array = bytearray(cont1.sha256)
         sha256_array[0] += 1
         cont1b = attr.evolve(cont1, sha256=bytes(sha256_array))
 
         with pytest.raises(HashCollision) as cm:
             swh_storage.content_add([cont1, cont1b])
 
         exc = cm.value
         actual_algo = exc.algo
         assert actual_algo in ["sha1", "sha1_git", "blake2s256"]
         actual_id = exc.hash_id
         assert actual_id == getattr(cont1, actual_algo).hex()
         collisions = exc.args[2]
         assert len(collisions) == 2
         assert collisions == [
             content_hex_hashes(cont1.hashes()),
             content_hex_hashes(cont1b.hashes()),
         ]
         assert exc.colliding_content_hashes() == [
             cont1.hashes(),
             cont1b.hashes(),
         ]
 
     def test_content_add_duplicate(self, swh_storage, sample_data):
         cont = sample_data.content
         swh_storage.content_add([cont, cont])
 
         assert list(swh_storage.content_get([cont.sha1])) == [
             {"sha1": cont.sha1, "data": cont.data}
         ]
 
     def test_content_update(self, swh_storage, sample_data):
         cont1 = sample_data.content
 
         if hasattr(swh_storage, "journal_writer"):
             swh_storage.journal_writer.journal = None  # TODO, not supported
 
         swh_storage.content_add([cont1])
 
         # alter the sha1_git for example
         cont1b = attr.evolve(
             cont1, sha1_git=hash_to_bytes("3a60a5275d0333bf13468e8b3dcab90f4046e654")
         )
 
         swh_storage.content_update([cont1b.to_dict()], keys=["sha1_git"])
 
         results = swh_storage.content_get_metadata([cont1.sha1])
 
         expected_content = attr.evolve(cont1b, data=None).to_dict()
         del expected_content["ctime"]
         assert tuple(results[cont1.sha1]) == (expected_content,)
 
     def test_content_add_metadata(self, swh_storage, sample_data):
         cont = attr.evolve(sample_data.content, data=None, ctime=now())
 
         actual_result = swh_storage.content_add_metadata([cont])
         assert actual_result == {
             "content:add": 1,
         }
 
         expected_cont = cont.to_dict()
         del expected_cont["ctime"]
 
         assert tuple(swh_storage.content_get_metadata([cont.sha1])[cont.sha1]) == (
             expected_cont,
         )
         contents = [
             obj
             for (obj_type, obj) in swh_storage.journal_writer.journal.objects
             if obj_type == "content"
         ]
         assert len(contents) == 1
         for obj in contents:
             obj = attr.evolve(obj, ctime=None)
             assert obj == cont
 
     def test_content_add_metadata_different_input(self, swh_storage, sample_data):
         contents = sample_data.contents[:2]
         cont = attr.evolve(contents[0], data=None, ctime=now())
         cont2 = attr.evolve(contents[1], data=None, ctime=now())
 
         actual_result = swh_storage.content_add_metadata([cont, cont2])
         assert actual_result == {
             "content:add": 2,
         }
 
     def test_content_add_metadata_collision(self, swh_storage, sample_data):
         cont1 = attr.evolve(sample_data.content, data=None, ctime=now())
 
         # create (corrupted) content with same sha1{,_git} but != sha256
         sha1_git_array = bytearray(cont1.sha256)
         sha1_git_array[0] += 1
         cont1b = attr.evolve(cont1, sha256=bytes(sha1_git_array))
 
         with pytest.raises(HashCollision) as cm:
             swh_storage.content_add_metadata([cont1, cont1b])
 
         exc = cm.value
         actual_algo = exc.algo
         assert actual_algo in ["sha1", "sha1_git", "blake2s256"]
         actual_id = exc.hash_id
         assert actual_id == getattr(cont1, actual_algo).hex()
         collisions = exc.args[2]
         assert len(collisions) == 2
         assert collisions == [
             content_hex_hashes(cont1.hashes()),
             content_hex_hashes(cont1b.hashes()),
         ]
         assert exc.colliding_content_hashes() == [
             cont1.hashes(),
             cont1b.hashes(),
         ]
 
     def test_skipped_content_add(self, swh_storage, sample_data):
         contents = sample_data.skipped_contents[:2]
         cont = contents[0]
         cont2 = attr.evolve(contents[1], blake2s256=None)
 
         contents_dict = [c.to_dict() for c in [cont, cont2]]
 
         missing = list(swh_storage.skipped_content_missing(contents_dict))
 
         assert missing == [cont.hashes(), cont2.hashes()]
 
         actual_result = swh_storage.skipped_content_add([cont, cont, cont2])
 
         assert 2 <= actual_result.pop("skipped_content:add") <= 3
         assert actual_result == {}
 
         missing = list(swh_storage.skipped_content_missing(contents_dict))
         assert missing == []
 
     def test_skipped_content_add_missing_hashes(self, swh_storage, sample_data):
         cont, cont2 = [
             attr.evolve(c, sha1_git=None) for c in sample_data.skipped_contents[:2]
         ]
         contents_dict = [c.to_dict() for c in [cont, cont2]]
 
         missing = list(swh_storage.skipped_content_missing(contents_dict))
         assert len(missing) == 2
 
         actual_result = swh_storage.skipped_content_add([cont, cont, cont2])
 
         assert 2 <= actual_result.pop("skipped_content:add") <= 3
         assert actual_result == {}
 
         missing = list(swh_storage.skipped_content_missing(contents_dict))
         assert missing == []
 
     def test_skipped_content_missing_partial_hash(self, swh_storage, sample_data):
         cont = sample_data.skipped_content
         cont2 = attr.evolve(cont, sha1_git=None)
         contents_dict = [c.to_dict() for c in [cont, cont2]]
 
         missing = list(swh_storage.skipped_content_missing(contents_dict))
         assert len(missing) == 2
 
         actual_result = swh_storage.skipped_content_add([cont])
 
         assert actual_result.pop("skipped_content:add") == 1
         assert actual_result == {}
 
         missing = list(swh_storage.skipped_content_missing(contents_dict))
         assert missing == [cont2.hashes()]
 
     @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, swh_storage, sample_data, algos):
         algos |= {"sha1"}
         content, missing_content = [sample_data.content2, sample_data.skipped_content]
         swh_storage.content_add([content])
 
         test_contents = [content.to_dict()]
         missing_per_hash = defaultdict(list)
         for i in range(256):
             test_content = missing_content.to_dict()
             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)
 
         assert set(swh_storage.content_missing(test_contents)) == set(
             missing_per_hash["sha1"]
         )
 
         for hash in algos:
             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, swh_storage, sample_data, algos):
         algos |= {"sha1"}
         content, missing_content = [sample_data.content2, sample_data.skipped_content]
         swh_storage.content_add([content])
 
         test_contents = [content.to_dict()]
         missing_per_hash = defaultdict(list)
         for i in range(16):
             test_content = missing_content.to_dict()
             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)
 
         assert set(swh_storage.content_missing(test_contents)) == set(
             missing_per_hash["sha1"]
         )
 
         for hash in algos:
             assert set(
                 swh_storage.content_missing(test_contents, key_hash=hash)
             ) == set(missing_per_hash[hash])
 
     def test_content_missing_per_sha1(self, swh_storage, sample_data):
         # given
         cont = sample_data.content
         missing_cont = sample_data.skipped_content
         swh_storage.content_add([cont])
 
         # when
         gen = swh_storage.content_missing_per_sha1([cont.sha1, missing_cont.sha1])
         # then
         assert list(gen) == [missing_cont.sha1]
 
     def test_content_missing_per_sha1_git(self, swh_storage, sample_data):
         cont, cont2 = sample_data.contents[:2]
         missing_cont = sample_data.skipped_content
 
         swh_storage.content_add([cont, cont2])
 
         contents = [cont.sha1_git, cont2.sha1_git, missing_cont.sha1_git]
 
         missing_contents = swh_storage.content_missing_per_sha1_git(contents)
         assert list(missing_contents) == [missing_cont.sha1_git]
 
     def test_content_get_partition(self, swh_storage, swh_contents):
         """content_get_partition paginates results if limit exceeded"""
         expected_contents = [c.to_dict() for c in swh_contents if c.status != "absent"]
 
         actual_contents = []
         for i in range(16):
             actual_result = swh_storage.content_get_partition(i, 16)
             assert actual_result["next_page_token"] is None
             actual_contents.extend(actual_result["contents"])
 
         assert_contents_ok(expected_contents, actual_contents, ["sha1"])
 
     def test_content_get_partition_full(self, swh_storage, swh_contents):
         """content_get_partition for a single partition returns all available
         contents"""
         expected_contents = [c.to_dict() for c in swh_contents if c.status != "absent"]
 
         actual_result = swh_storage.content_get_partition(0, 1)
         assert actual_result["next_page_token"] is None
 
         actual_contents = actual_result["contents"]
         assert_contents_ok(expected_contents, actual_contents, ["sha1"])
 
     def test_content_get_partition_empty(self, swh_storage, swh_contents):
         """content_get_partition when at least one of the partitions is
         empty"""
         expected_contents = {
             cont.sha1 for cont in swh_contents if cont.status != "absent"
         }
         # nb_partitions = smallest power of 2 such that at least one of
         # the partitions is empty
         nb_partitions = 1 << math.floor(math.log2(len(swh_contents)) + 1)
 
         seen_sha1s = []
 
         for i in range(nb_partitions):
             actual_result = swh_storage.content_get_partition(
                 i, nb_partitions, limit=len(swh_contents) + 1
             )
 
             for cont in actual_result["contents"]:
                 seen_sha1s.append(cont["sha1"])
 
             # Limit is higher than the max number of results
             assert actual_result["next_page_token"] is None
 
         assert set(seen_sha1s) == expected_contents
 
     def test_content_get_partition_limit_none(self, swh_storage):
         """content_get_partition call with wrong limit input should fail"""
         with pytest.raises(StorageArgumentException) as e:
             swh_storage.content_get_partition(1, 16, limit=None)
 
         assert e.value.args == ("limit should not be None",)
 
     def test_generate_content_get_partition_pagination(self, swh_storage, swh_contents):
         """content_get_partition returns contents within range provided"""
         expected_contents = [c.to_dict() for c in swh_contents if c.status != "absent"]
 
         # retrieve contents
         actual_contents = []
         for i in range(4):
             page_token = None
             while True:
                 actual_result = swh_storage.content_get_partition(
                     i, 4, limit=3, page_token=page_token
                 )
                 actual_contents.extend(actual_result["contents"])
                 page_token = actual_result["next_page_token"]
 
                 if page_token is None:
                     break
 
         assert_contents_ok(expected_contents, actual_contents, ["sha1"])
 
     def test_content_get_metadata(self, swh_storage, sample_data):
         cont1, cont2 = sample_data.contents[:2]
 
         swh_storage.content_add([cont1, cont2])
 
         actual_md = swh_storage.content_get_metadata([cont1.sha1, cont2.sha1])
 
         # we only retrieve the metadata so no data nor ctime within
         expected_cont1, expected_cont2 = [
             attr.evolve(c, data=None).to_dict() for c in [cont1, cont2]
         ]
         expected_cont1.pop("ctime")
         expected_cont2.pop("ctime")
 
         assert tuple(actual_md[cont1.sha1]) == (expected_cont1,)
         assert tuple(actual_md[cont2.sha1]) == (expected_cont2,)
         assert len(actual_md.keys()) == 2
 
     def test_content_get_metadata_missing_sha1(self, swh_storage, sample_data):
         cont1, cont2 = sample_data.contents[:2]
         missing_cont = sample_data.skipped_content
 
         swh_storage.content_add([cont1, cont2])
 
         actual_contents = swh_storage.content_get_metadata([missing_cont.sha1])
 
         assert len(actual_contents) == 1
         assert tuple(actual_contents[missing_cont.sha1]) == ()
 
     def test_content_get_random(self, swh_storage, sample_data):
         cont, cont2, cont3 = sample_data.contents[:3]
         swh_storage.content_add([cont, cont2, cont3])
 
         assert swh_storage.content_get_random() in {
             cont.sha1_git,
             cont2.sha1_git,
             cont3.sha1_git,
         }
 
     def test_directory_add(self, swh_storage, sample_data):
         directory = sample_data.directories[1]
 
         init_missing = list(swh_storage.directory_missing([directory.id]))
         assert [directory.id] == init_missing
 
         actual_result = swh_storage.directory_add([directory])
         assert actual_result == {"directory:add": 1}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("directory", directory)
         ]
 
         actual_data = list(swh_storage.directory_ls(directory.id))
         expected_data = list(transform_entries(directory))
 
         assert sorted(expected_data, key=cmpdir) == sorted(actual_data, key=cmpdir)
 
         after_missing = list(swh_storage.directory_missing([directory.id]))
         assert after_missing == []
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["directory"] == 1
 
     def test_directory_add_from_generator(self, swh_storage, sample_data):
         directory = sample_data.directories[1]
 
         def _dir_gen():
             yield directory
 
         actual_result = swh_storage.directory_add(directories=_dir_gen())
         assert actual_result == {"directory:add": 1}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("directory", directory)
         ]
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["directory"] == 1
 
     def test_directory_add_twice(self, swh_storage, sample_data):
         directory = sample_data.directories[1]
 
         actual_result = swh_storage.directory_add([directory])
         assert actual_result == {"directory:add": 1}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("directory", directory)
         ]
 
         actual_result = swh_storage.directory_add([directory])
         assert actual_result == {"directory:add": 0}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("directory", directory)
         ]
 
     def test_directory_get_recursive(self, swh_storage, sample_data):
         dir1, dir2, dir3 = sample_data.directories[:3]
 
         init_missing = list(swh_storage.directory_missing([dir1.id]))
         assert init_missing == [dir1.id]
 
         actual_result = swh_storage.directory_add([dir1, dir2, dir3])
         assert actual_result == {"directory:add": 3}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("directory", dir1),
             ("directory", dir2),
             ("directory", dir3),
         ]
 
         # List directory containing a file and an unknown subdirectory
         actual_data = list(swh_storage.directory_ls(dir1.id, recursive=True))
         expected_data = list(transform_entries(dir1))
         assert sorted(expected_data, key=cmpdir) == sorted(actual_data, key=cmpdir)
 
         # List directory containing a file and an unknown subdirectory
         actual_data = list(swh_storage.directory_ls(dir2.id, recursive=True))
         expected_data = list(transform_entries(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(swh_storage.directory_ls(dir3.id, recursive=True))
         expected_data = list(
             itertools.chain(
                 transform_entries(dir3), transform_entries(dir2, prefix=b"subdir/"),
             )
         )
         assert sorted(expected_data, key=cmpdir) == sorted(actual_data, key=cmpdir)
 
     def test_directory_get_non_recursive(self, swh_storage, sample_data):
         dir1, dir2, dir3 = sample_data.directories[:3]
 
         init_missing = list(swh_storage.directory_missing([dir1.id]))
         assert init_missing == [dir1.id]
 
         actual_result = swh_storage.directory_add([dir1, dir2, dir3])
         assert actual_result == {"directory:add": 3}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("directory", dir1),
             ("directory", dir2),
             ("directory", dir3),
         ]
 
         # List directory containing a file and an unknown subdirectory
         actual_data = list(swh_storage.directory_ls(dir1.id))
         expected_data = list(transform_entries(dir1))
         assert sorted(expected_data, key=cmpdir) == sorted(actual_data, key=cmpdir)
 
         # List directory contaiining a single file
         actual_data = list(swh_storage.directory_ls(dir2.id))
         expected_data = list(transform_entries(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(swh_storage.directory_ls(dir3.id))
         expected_data = list(transform_entries(dir3))
         assert sorted(expected_data, key=cmpdir) == sorted(actual_data, key=cmpdir)
 
     def test_directory_entry_get_by_path(self, swh_storage, sample_data):
         cont = sample_data.content
         dir1, dir2, dir3, dir4, dir5 = sample_data.directories[:5]
 
         # given
         init_missing = list(swh_storage.directory_missing([dir3.id]))
         assert init_missing == [dir3.id]
 
         actual_result = swh_storage.directory_add([dir3, dir4])
         assert actual_result == {"directory:add": 2}
 
         expected_entries = [
             {
                 "dir_id": dir3.id,
                 "name": b"foo",
                 "type": "file",
                 "target": cont.sha1_git,
                 "sha1": None,
                 "sha1_git": None,
                 "sha256": None,
                 "status": None,
                 "perms": from_disk.DentryPerms.content,
                 "length": None,
             },
             {
                 "dir_id": dir3.id,
                 "name": b"subdir",
                 "type": "dir",
                 "target": dir2.id,
                 "sha1": None,
                 "sha1_git": None,
                 "sha256": None,
                 "status": None,
                 "perms": from_disk.DentryPerms.directory,
                 "length": None,
             },
             {
                 "dir_id": dir3.id,
                 "name": b"hello",
                 "type": "file",
                 "target": dir5.id,
                 "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(dir3.entries, expected_entries):
             actual_entry = swh_storage.directory_entry_get_by_path(
                 dir3.id, [entry.name]
             )
             assert actual_entry == expected_entry
 
         # same, but deeper
         for entry, expected_entry in zip(dir3.entries, expected_entries):
             actual_entry = swh_storage.directory_entry_get_by_path(
                 dir4.id, [b"subdir1", entry.name]
             )
             expected_entry = expected_entry.copy()
             expected_entry["name"] = b"subdir1/" + expected_entry["name"]
             assert actual_entry == expected_entry
 
         # when (nothing should be found here since `dir` is not persisted.)
         for entry in dir2.entries:
             actual_entry = swh_storage.directory_entry_get_by_path(
                 dir2.id, [entry.name]
             )
             assert actual_entry is None
 
     def test_directory_get_random(self, swh_storage, sample_data):
         dir1, dir2, dir3 = sample_data.directories[:3]
         swh_storage.directory_add([dir1, dir2, dir3])
 
         assert swh_storage.directory_get_random() in {
             dir1.id,
             dir2.id,
             dir3.id,
         }
 
     def test_revision_add(self, swh_storage, sample_data):
         revision = sample_data.revision
         init_missing = swh_storage.revision_missing([revision.id])
         assert list(init_missing) == [revision.id]
 
         actual_result = swh_storage.revision_add([revision])
         assert actual_result == {"revision:add": 1}
 
         end_missing = swh_storage.revision_missing([revision.id])
         assert list(end_missing) == []
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("revision", revision)
         ]
 
         # already there so nothing added
         actual_result = swh_storage.revision_add([revision])
         assert actual_result == {"revision:add": 0}
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["revision"] == 1
 
     def test_revision_add_from_generator(self, swh_storage, sample_data):
         revision = sample_data.revision
 
         def _rev_gen():
             yield revision
 
         actual_result = swh_storage.revision_add(_rev_gen())
         assert actual_result == {"revision:add": 1}
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["revision"] == 1
 
     def test_revision_add_twice(self, swh_storage, sample_data):
         revision, revision2 = sample_data.revisions[:2]
 
         actual_result = swh_storage.revision_add([revision])
         assert actual_result == {"revision:add": 1}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("revision", revision)
         ]
 
         actual_result = swh_storage.revision_add([revision, revision2])
         assert actual_result == {"revision:add": 1}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("revision", revision),
             ("revision", revision2),
         ]
 
     def test_revision_add_name_clash(self, swh_storage, sample_data):
         revision, revision2 = sample_data.revisions[:2]
 
         revision1 = attr.evolve(
             revision,
             author=Person(
                 fullname=b"John Doe <john.doe@example.com>",
                 name=b"John Doe",
                 email=b"john.doe@example.com",
             ),
         )
         revision2 = attr.evolve(
             revision2,
             author=Person(
                 fullname=b"John Doe <john.doe@example.com>",
                 name=b"John Doe ",
                 email=b"john.doe@example.com ",
             ),
         )
         actual_result = swh_storage.revision_add([revision1, revision2])
         assert actual_result == {"revision:add": 2}
 
     def test_revision_get_order(self, swh_storage, sample_data):
         revision, revision2 = sample_data.revisions[:2]
 
         add_result = swh_storage.revision_add([revision, revision2])
         assert add_result == {"revision:add": 2}
 
         # order 1
         res1 = swh_storage.revision_get([revision.id, revision2.id])
 
         assert [Revision.from_dict(r) for r in res1] == [revision, revision2]
 
         # order 2
         res2 = swh_storage.revision_get([revision2.id, revision.id])
         assert [Revision.from_dict(r) for r in res2] == [revision2, revision]
 
     def test_revision_log(self, swh_storage, sample_data):
         revision1, revision2, revision3, revision4 = sample_data.revisions[:4]
 
         # rev4 -is-child-of-> rev3 -> rev1, (rev2 -> rev1)
         swh_storage.revision_add([revision1, revision2, revision3, revision4])
 
         # when
         results = list(swh_storage.revision_log([revision4.id]))
 
         # for comparison purposes
         actual_results = [Revision.from_dict(r) for r in results]
         assert len(actual_results) == 4  # rev4 -child-> rev3 -> rev1, (rev2 -> rev1)
         assert actual_results == [revision4, revision3, revision1, revision2]
 
     def test_revision_log_with_limit(self, swh_storage, sample_data):
         revision1, revision2, revision3, revision4 = sample_data.revisions[:4]
 
         # revision4 -is-child-of-> revision3
         swh_storage.revision_add([revision3, revision4])
         results = list(swh_storage.revision_log([revision4.id], 1))
 
         actual_results = [Revision.from_dict(r) for r in results]
         assert len(actual_results) == 1
         assert actual_results[0] == revision4
 
     def test_revision_log_unknown_revision(self, swh_storage, sample_data):
         revision = sample_data.revision
         rev_log = list(swh_storage.revision_log([revision.id]))
         assert rev_log == []
 
     def test_revision_shortlog(self, swh_storage, sample_data):
         revision1, revision2, revision3, revision4 = sample_data.revisions[:4]
 
         # rev4 -is-child-of-> rev3 -> (rev1, rev2); rev2 -> rev1
         swh_storage.revision_add([revision1, revision2, revision3, revision4])
 
         results = list(swh_storage.revision_shortlog([revision4.id]))
         actual_results = [[id, tuple(parents)] for (id, parents) in results]
 
         assert len(actual_results) == 4
         assert actual_results == [
             [revision4.id, revision4.parents],
             [revision3.id, revision3.parents],
             [revision1.id, revision1.parents],
             [revision2.id, revision2.parents],
         ]
 
     def test_revision_shortlog_with_limit(self, swh_storage, sample_data):
         revision1, revision2, revision3, revision4 = sample_data.revisions[:4]
 
         # revision4 -is-child-of-> revision3
         swh_storage.revision_add([revision1, revision2, revision3, revision4])
         results = list(swh_storage.revision_shortlog([revision4.id], 1))
         actual_results = [[id, tuple(parents)] for (id, parents) in results]
 
         assert len(actual_results) == 1
         assert list(actual_results[0]) == [revision4.id, revision4.parents]
 
     def test_revision_get(self, swh_storage, sample_data):
         revision, revision2 = sample_data.revisions[:2]
 
         swh_storage.revision_add([revision])
 
         actual_revisions = list(swh_storage.revision_get([revision.id, revision2.id]))
 
         assert len(actual_revisions) == 2
         assert Revision.from_dict(actual_revisions[0]) == revision
         assert actual_revisions[1] is None
 
     def test_revision_get_no_parents(self, swh_storage, sample_data):
         revision = sample_data.revision
         swh_storage.revision_add([revision])
 
         get = list(swh_storage.revision_get([revision.id]))
 
         assert len(get) == 1
         assert revision.parents == ()
         assert tuple(get[0]["parents"]) == ()  # no parents on this one
 
     def test_revision_get_random(self, swh_storage, sample_data):
         revision1, revision2, revision3 = sample_data.revisions[:3]
 
         swh_storage.revision_add([revision1, revision2, revision3])
 
         assert swh_storage.revision_get_random() in {
             revision1.id,
             revision2.id,
             revision3.id,
         }
 
     def test_release_add(self, swh_storage, sample_data):
         release, release2 = sample_data.releases[:2]
 
         init_missing = swh_storage.release_missing([release.id, release2.id])
         assert list(init_missing) == [release.id, release2.id]
 
         actual_result = swh_storage.release_add([release, release2])
         assert actual_result == {"release:add": 2}
 
         end_missing = swh_storage.release_missing([release.id, release2.id])
         assert list(end_missing) == []
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("release", release),
             ("release", release2),
         ]
 
         # already present so nothing added
         actual_result = swh_storage.release_add([release, release2])
         assert actual_result == {"release:add": 0}
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["release"] == 2
 
     def test_release_add_from_generator(self, swh_storage, sample_data):
         release, release2 = sample_data.releases[:2]
 
         def _rel_gen():
             yield release
             yield release2
 
         actual_result = swh_storage.release_add(_rel_gen())
         assert actual_result == {"release:add": 2}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("release", release),
             ("release", release2),
         ]
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["release"] == 2
 
     def test_release_add_no_author_date(self, swh_storage, sample_data):
         full_release = sample_data.release
 
         release = attr.evolve(full_release, author=None, date=None)
         actual_result = swh_storage.release_add([release])
         assert actual_result == {"release:add": 1}
 
         end_missing = swh_storage.release_missing([release.id])
         assert list(end_missing) == []
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("release", release)
         ]
 
     def test_release_add_twice(self, swh_storage, sample_data):
         release, release2 = sample_data.releases[:2]
 
         actual_result = swh_storage.release_add([release])
         assert actual_result == {"release:add": 1}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("release", release)
         ]
 
         actual_result = swh_storage.release_add([release, release2, release, release2])
         assert actual_result == {"release:add": 1}
 
         assert set(swh_storage.journal_writer.journal.objects) == set(
             [("release", release), ("release", release2),]
         )
 
     def test_release_add_name_clash(self, swh_storage, sample_data):
         release, release2 = [
             attr.evolve(
                 c,
                 author=Person(
                     fullname=b"John Doe <john.doe@example.com>",
                     name=b"John Doe",
                     email=b"john.doe@example.com",
                 ),
             )
             for c in sample_data.releases[:2]
         ]
 
         actual_result = swh_storage.release_add([release, release2])
         assert actual_result == {"release:add": 2}
 
     def test_release_get(self, swh_storage, sample_data):
         release, release2, release3 = sample_data.releases[:3]
 
         # given
         swh_storage.release_add([release, release2])
 
         # when
         releases = list(swh_storage.release_get([release.id, release2.id]))
         actual_releases = [Release.from_dict(r) for r in releases]
 
         # then
         assert actual_releases == [release, release2]
 
         unknown_releases = list(swh_storage.release_get([release3.id]))
         assert unknown_releases[0] is None
 
     def test_release_get_order(self, swh_storage, sample_data):
         release, release2 = sample_data.releases[:2]
 
         add_result = swh_storage.release_add([release, release2])
         assert add_result == {"release:add": 2}
 
         # order 1
         res1 = swh_storage.release_get([release.id, release2.id])
         assert list(res1) == [release.to_dict(), release2.to_dict()]
 
         # order 2
         res2 = swh_storage.release_get([release2.id, release.id])
         assert list(res2) == [release2.to_dict(), release.to_dict()]
 
     def test_release_get_random(self, swh_storage, sample_data):
         release, release2, release3 = sample_data.releases[:3]
 
         swh_storage.release_add([release, release2, release3])
 
         assert swh_storage.release_get_random() in {
             release.id,
             release2.id,
             release3.id,
         }
 
     def test_origin_add(self, swh_storage, sample_data):
         origins = list(sample_data.origins[:2])
         origin_urls = [o.url for o in origins]
 
         assert swh_storage.origin_get(origin_urls) == [None, None]
 
         stats = swh_storage.origin_add(origins)
         assert stats == {"origin:add": 2}
 
         actual_origins = swh_storage.origin_get(origin_urls)
         assert actual_origins == origins
 
         assert set(swh_storage.journal_writer.journal.objects) == set(
             [("origin", origins[0]), ("origin", origins[1]),]
         )
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["origin"] == 2
 
     def test_origin_add_from_generator(self, swh_storage, sample_data):
         origin, origin2 = sample_data.origins[:2]
 
         def _ori_gen():
             yield origin
             yield origin2
 
         stats = swh_storage.origin_add(_ori_gen())
         assert stats == {"origin:add": 2}
 
         actual_origins = swh_storage.origin_get([origin.url, origin2.url])
         assert actual_origins == [origin, origin2]
 
         assert set(swh_storage.journal_writer.journal.objects) == set(
             [("origin", origin), ("origin", origin2),]
         )
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["origin"] == 2
 
     def test_origin_add_twice(self, swh_storage, sample_data):
         origin, origin2 = sample_data.origins[:2]
 
         add1 = swh_storage.origin_add([origin, origin2])
         assert set(swh_storage.journal_writer.journal.objects) == set(
             [("origin", origin), ("origin", origin2),]
         )
         assert add1 == {"origin:add": 2}
 
         add2 = swh_storage.origin_add([origin, origin2])
         assert set(swh_storage.journal_writer.journal.objects) == set(
             [("origin", origin), ("origin", origin2),]
         )
         assert add2 == {"origin:add": 0}
 
     def test_origin_get(self, swh_storage, sample_data):
         origin, origin2 = sample_data.origins[:2]
 
         assert swh_storage.origin_get([origin.url]) == [None]
         swh_storage.origin_add([origin])
 
         actual_origins = swh_storage.origin_get([origin.url])
         assert actual_origins == [origin]
 
         actual_origins = swh_storage.origin_get([origin.url, "not://exists"])
         assert actual_origins == [origin, None]
 
     def _generate_random_visits(self, nb_visits=100, start=0, end=7):
         """Generate random visits within the last 2 months (to avoid
         computations)
 
         """
         visits = []
         today = now()
         for weeks in range(nb_visits, 0, -1):
             hours = random.randint(0, 24)
             minutes = random.randint(0, 60)
             seconds = random.randint(0, 60)
             days = random.randint(0, 28)
             weeks = random.randint(start, end)
             date_visit = today - timedelta(
                 weeks=weeks, hours=hours, minutes=minutes, seconds=seconds, days=days
             )
             visits.append(date_visit)
         return visits
 
     def test_origin_visit_get_all(self, swh_storage, sample_data):
         origin = sample_data.origin
         swh_storage.origin_add([origin])
         visits = swh_storage.origin_visit_add(
             [
                 OriginVisit(
                     origin=origin.url,
                     date=sample_data.date_visit1,
                     type=sample_data.type_visit1,
                 ),
                 OriginVisit(
                     origin=origin.url,
                     date=sample_data.date_visit2,
                     type=sample_data.type_visit2,
                 ),
                 OriginVisit(
                     origin=origin.url,
                     date=sample_data.date_visit2,
                     type=sample_data.type_visit2,
                 ),
             ]
         )
         ov1, ov2, ov3 = [
             {**v.to_dict(), "status": "created", "snapshot": None, "metadata": None,}
             for v in visits
         ]
 
         # order asc, no pagination, no limit
         all_visits = list(swh_storage.origin_visit_get(origin.url))
         assert all_visits == [ov1, ov2, ov3]
 
         # order asc, no pagination, limit
         all_visits2 = list(swh_storage.origin_visit_get(origin.url, limit=2))
         assert all_visits2 == [ov1, ov2]
 
         # order asc, pagination, no limit
         all_visits3 = list(
             swh_storage.origin_visit_get(origin.url, last_visit=ov1["visit"])
         )
         assert all_visits3 == [ov2, ov3]
 
         # order asc, pagination, limit
         all_visits4 = list(
             swh_storage.origin_visit_get(origin.url, last_visit=ov2["visit"], limit=1)
         )
         assert all_visits4 == [ov3]
 
         # order desc, no pagination, no limit
         all_visits5 = list(swh_storage.origin_visit_get(origin.url, order="desc"))
         assert all_visits5 == [ov3, ov2, ov1]
 
         # order desc, no pagination, limit
         all_visits6 = list(
             swh_storage.origin_visit_get(origin.url, limit=2, order="desc")
         )
         assert all_visits6 == [ov3, ov2]
 
         # order desc, pagination, no limit
         all_visits7 = list(
             swh_storage.origin_visit_get(
                 origin.url, last_visit=ov3["visit"], order="desc"
             )
         )
         assert all_visits7 == [ov2, ov1]
 
         # order desc, pagination, limit
         all_visits8 = list(
             swh_storage.origin_visit_get(
                 origin.url, last_visit=ov3["visit"], order="desc", limit=1
             )
         )
         assert all_visits8 == [ov2]
 
     def test_origin_visit_get__unknown_origin(self, swh_storage):
         assert [] == list(swh_storage.origin_visit_get("foo"))
 
     def test_origin_visit_status_get_random(self, swh_storage, sample_data):
         origins = sample_data.origins[:2]
         swh_storage.origin_add(origins)
 
         # Add some random visits within the selection range
         visits = self._generate_random_visits()
         visit_type = "git"
 
         # Add visits to those origins
         for origin in origins:
             for date_visit in visits:
                 visit = swh_storage.origin_visit_add(
                     [OriginVisit(origin=origin.url, date=date_visit, type=visit_type,)]
                 )[0]
                 swh_storage.origin_visit_status_add(
                     [
                         OriginVisitStatus(
                             origin=origin.url,
                             visit=visit.visit,
                             date=now(),
                             status="full",
                             snapshot=None,
                         )
                     ]
                 )
 
         swh_storage.refresh_stat_counters()
 
         stats = swh_storage.stat_counters()
         assert stats["origin"] == len(origins)
         assert stats["origin_visit"] == len(origins) * len(visits)
 
         random_ov, random_ovs = swh_storage.origin_visit_status_get_random(visit_type)
         assert random_ov and random_ovs
         assert random_ov.origin is not None
         assert random_ov.origin == random_ovs.origin
         assert random_ov.origin in [o.url for o in origins]
 
     def test_origin_visit_status_get_random_nothing_found(
         self, swh_storage, sample_data
     ):
         origins = sample_data.origins
         swh_storage.origin_add(origins)
         visit_type = "hg"
         # Add some visits outside of the random generation selection so nothing
         # will be found by the random selection
         visits = self._generate_random_visits(nb_visits=3, start=13, end=24)
         for origin in origins:
             for date_visit in visits:
                 visit = swh_storage.origin_visit_add(
                     [OriginVisit(origin=origin.url, date=date_visit, type=visit_type,)]
                 )[0]
                 swh_storage.origin_visit_status_add(
                     [
                         OriginVisitStatus(
                             origin=origin.url,
                             visit=visit.visit,
                             date=now(),
                             status="full",
                             snapshot=None,
                         )
                     ]
                 )
 
         random_origin_visit = swh_storage.origin_visit_status_get_random(visit_type)
         assert random_origin_visit is None
 
     def test_origin_get_by_sha1(self, swh_storage, sample_data):
         origin = sample_data.origin
         assert swh_storage.origin_get([origin.url])[0] is None
         swh_storage.origin_add([origin])
 
         origins = list(swh_storage.origin_get_by_sha1([sha1(origin.url)]))
         assert len(origins) == 1
         assert origins[0]["url"] == origin.url
 
     def test_origin_get_by_sha1_not_found(self, swh_storage, sample_data):
         origin = sample_data.origin
         assert swh_storage.origin_get([origin.url])[0] is None
         origins = list(swh_storage.origin_get_by_sha1([sha1(origin.url)]))
         assert len(origins) == 1
         assert origins[0] is None
 
     def test_origin_search_single_result(self, swh_storage, sample_data):
         origin, origin2 = sample_data.origins[:2]
 
         found_origins = list(swh_storage.origin_search(origin.url))
         assert len(found_origins) == 0
 
         found_origins = list(swh_storage.origin_search(origin.url, regexp=True))
         assert len(found_origins) == 0
 
         swh_storage.origin_add([origin])
         origin_data = origin.to_dict()
         found_origins = list(swh_storage.origin_search(origin.url))
 
         assert len(found_origins) == 1
         assert found_origins[0] == origin_data
 
         found_origins = list(
             swh_storage.origin_search(f".{origin.url[1:-1]}.", regexp=True)
         )
         assert len(found_origins) == 1
         assert found_origins[0] == origin_data
 
         swh_storage.origin_add([origin2])
         origin2_data = origin2.to_dict()
         found_origins = list(swh_storage.origin_search(origin2.url))
         assert len(found_origins) == 1
         assert found_origins[0] == origin2_data
 
         found_origins = list(
             swh_storage.origin_search(f".{origin2.url[1:-1]}.", regexp=True)
         )
         assert len(found_origins) == 1
         assert found_origins[0] == origin2_data
 
     def test_origin_search_no_regexp(self, swh_storage, sample_data):
         origin, origin2 = sample_data.origins[:2]
         origin_dicts = [o.to_dict() for o in [origin, origin2]]
 
         swh_storage.origin_add([origin, origin2])
 
         # no pagination
         found_origins = list(swh_storage.origin_search("/"))
         assert len(found_origins) == 2
 
         # offset=0
         found_origins0 = list(swh_storage.origin_search("/", offset=0, limit=1))
         assert len(found_origins0) == 1
         assert found_origins0[0] in origin_dicts
 
         # offset=1
         found_origins1 = list(swh_storage.origin_search("/", offset=1, limit=1))
         assert len(found_origins1) == 1
         assert found_origins1[0] in origin_dicts
 
         # check both origins were returned
         assert found_origins0 != found_origins1
 
     def test_origin_search_regexp_substring(self, swh_storage, sample_data):
         origin, origin2 = sample_data.origins[:2]
         origin_dicts = [o.to_dict() for o in [origin, origin2]]
 
         swh_storage.origin_add([origin, origin2])
 
         # no pagination
         found_origins = list(swh_storage.origin_search("/", regexp=True))
         assert len(found_origins) == 2
 
         # offset=0
         found_origins0 = list(
             swh_storage.origin_search("/", offset=0, limit=1, regexp=True)
         )
         assert len(found_origins0) == 1
         assert found_origins0[0] in origin_dicts
 
         # offset=1
         found_origins1 = list(
             swh_storage.origin_search("/", offset=1, limit=1, regexp=True)
         )
         assert len(found_origins1) == 1
         assert found_origins1[0] in origin_dicts
 
         # check both origins were returned
         assert found_origins0 != found_origins1
 
     def test_origin_search_regexp_fullstring(self, swh_storage, sample_data):
         origin, origin2 = sample_data.origins[:2]
         origin_dicts = [o.to_dict() for o in [origin, origin2]]
 
         swh_storage.origin_add([origin, origin2])
 
         # no pagination
         found_origins = list(swh_storage.origin_search(".*/.*", regexp=True))
         assert len(found_origins) == 2
 
         # offset=0
         found_origins0 = list(
             swh_storage.origin_search(".*/.*", offset=0, limit=1, regexp=True)
         )
         assert len(found_origins0) == 1
         assert found_origins0[0] in origin_dicts
 
         # offset=1
         found_origins1 = list(
             swh_storage.origin_search(".*/.*", offset=1, limit=1, regexp=True)
         )
         assert len(found_origins1) == 1
         assert found_origins1[0] in origin_dicts
 
         # check both origins were returned
         assert found_origins0 != found_origins1
 
     def test_origin_visit_add(self, swh_storage, sample_data):
         origin1 = sample_data.origins[1]
         swh_storage.origin_add([origin1])
 
         date_visit = now()
         date_visit2 = date_visit + datetime.timedelta(minutes=1)
 
         date_visit = round_to_milliseconds(date_visit)
         date_visit2 = round_to_milliseconds(date_visit2)
 
         visit1 = OriginVisit(
             origin=origin1.url, date=date_visit, type=sample_data.type_visit1,
         )
         visit2 = OriginVisit(
             origin=origin1.url, date=date_visit2, type=sample_data.type_visit2,
         )
 
         # add once
         ov1, ov2 = swh_storage.origin_visit_add([visit1, visit2])
         # then again (will be ignored as they already exist)
         origin_visit1, origin_visit2 = swh_storage.origin_visit_add([ov1, ov2])
         assert ov1 == origin_visit1
         assert ov2 == origin_visit2
 
         ovs1 = OriginVisitStatus(
             origin=origin1.url,
             visit=ov1.visit,
             date=date_visit,
             status="created",
             snapshot=None,
         )
         ovs2 = OriginVisitStatus(
             origin=origin1.url,
             visit=ov2.visit,
             date=date_visit2,
             status="created",
             snapshot=None,
         )
 
         actual_origin_visits = list(swh_storage.origin_visit_get(origin1.url))
         expected_visits = [
             {**ovs1.to_dict(), "type": ov1.type},
             {**ovs2.to_dict(), "type": ov2.type},
         ]
 
         assert len(expected_visits) == len(actual_origin_visits)
 
         for visit in expected_visits:
             assert visit in actual_origin_visits
 
         actual_objects = list(swh_storage.journal_writer.journal.objects)
         expected_objects = list(
             [("origin", origin1)]
             + [("origin_visit", visit) for visit in [ov1, ov2]] * 2
             + [("origin_visit_status", ovs) for ovs in [ovs1, ovs2]]
         )
 
         for obj in expected_objects:
             assert obj in actual_objects
 
     def test_origin_visit_add_validation(self, swh_storage, sample_data):
         """Unknown origin when adding visits should raise"""
         visit = attr.evolve(sample_data.origin_visit, origin="something-unknonw")
         with pytest.raises(StorageArgumentException, match="Unknown origin"):
             swh_storage.origin_visit_add([visit])
 
         objects = list(swh_storage.journal_writer.journal.objects)
         assert not objects
 
     def test_origin_visit_status_add_validation(self, swh_storage):
         """Wrong origin_visit_status input should raise storage argument error"""
         date_visit = now()
         visit_status1 = OriginVisitStatus(
             origin="unknown-origin-url",
             visit=10,
             date=date_visit,
             status="full",
             snapshot=None,
         )
         with pytest.raises(StorageArgumentException, match="Unknown origin"):
             swh_storage.origin_visit_status_add([visit_status1])
 
         objects = list(swh_storage.journal_writer.journal.objects)
         assert not objects
 
     def test_origin_visit_status_add(self, swh_storage, sample_data):
         """Correct origin visit statuses should add a new visit status
 
         """
         snapshot = sample_data.snapshot
         origin1 = sample_data.origins[1]
         origin2 = Origin(url="new-origin")
         swh_storage.origin_add([origin1, origin2])
 
         ov1, ov2 = swh_storage.origin_visit_add(
             [
                 OriginVisit(
                     origin=origin1.url,
                     date=sample_data.date_visit1,
                     type=sample_data.type_visit1,
                 ),
                 OriginVisit(
                     origin=origin2.url,
                     date=sample_data.date_visit2,
                     type=sample_data.type_visit2,
                 ),
             ]
         )
 
         ovs1 = OriginVisitStatus(
             origin=origin1.url,
             visit=ov1.visit,
             date=sample_data.date_visit1,
             status="created",
             snapshot=None,
         )
         ovs2 = OriginVisitStatus(
             origin=origin2.url,
             visit=ov2.visit,
             date=sample_data.date_visit2,
             status="created",
             snapshot=None,
         )
 
         date_visit_now = now()
         visit_status1 = OriginVisitStatus(
             origin=ov1.origin,
             visit=ov1.visit,
             date=date_visit_now,
             status="full",
             snapshot=snapshot.id,
         )
 
         date_visit_now = now()
         visit_status2 = OriginVisitStatus(
             origin=ov2.origin,
             visit=ov2.visit,
             date=date_visit_now,
             status="ongoing",
             snapshot=None,
             metadata={"intrinsic": "something"},
         )
         swh_storage.origin_visit_status_add([visit_status1, visit_status2])
 
         origin_visit1 = swh_storage.origin_visit_get_latest(
             origin1.url, require_snapshot=True
         )
         assert origin_visit1
         assert origin_visit1["status"] == "full"
         assert origin_visit1["snapshot"] == snapshot.id
 
         origin_visit2 = swh_storage.origin_visit_get_latest(
             origin2.url, require_snapshot=False
         )
         assert origin2.url != origin1.url
         assert origin_visit2
         assert origin_visit2["status"] == "ongoing"
         assert origin_visit2["snapshot"] is None
         assert origin_visit2["metadata"] == {"intrinsic": "something"}
 
         actual_objects = list(swh_storage.journal_writer.journal.objects)
 
         expected_origins = [origin1, origin2]
         expected_visits = [ov1, ov2]
         expected_visit_statuses = [ovs1, ovs2, visit_status1, visit_status2]
 
         expected_objects = (
             [("origin", o) for o in expected_origins]
             + [("origin_visit", v) for v in expected_visits]
             + [("origin_visit_status", ovs) for ovs in expected_visit_statuses]
         )
 
         for obj in expected_objects:
             assert obj in actual_objects
 
     def test_origin_visit_status_add_twice(self, swh_storage, sample_data):
         """Correct origin visit statuses should add a new visit status
 
         """
         snapshot = sample_data.snapshot
         origin1 = sample_data.origins[1]
         swh_storage.origin_add([origin1])
         ov1 = swh_storage.origin_visit_add(
             [
                 OriginVisit(
                     origin=origin1.url,
                     date=sample_data.date_visit1,
                     type=sample_data.type_visit1,
                 ),
             ]
         )[0]
 
         ovs1 = OriginVisitStatus(
             origin=origin1.url,
             visit=ov1.visit,
             date=sample_data.date_visit1,
             status="created",
             snapshot=None,
         )
         date_visit_now = now()
         visit_status1 = OriginVisitStatus(
             origin=ov1.origin,
             visit=ov1.visit,
             date=date_visit_now,
             status="full",
             snapshot=snapshot.id,
         )
 
         swh_storage.origin_visit_status_add([visit_status1])
         # second call will ignore existing entries (will send to storage though)
         swh_storage.origin_visit_status_add([visit_status1])
 
         origin_visits = list(swh_storage.origin_visit_get(ov1.origin))
 
         assert len(origin_visits) == 1
         origin_visit1 = origin_visits[0]
         assert origin_visit1
         assert origin_visit1["status"] == "full"
         assert origin_visit1["snapshot"] == snapshot.id
 
         actual_objects = list(swh_storage.journal_writer.journal.objects)
 
         expected_origins = [origin1]
         expected_visits = [ov1]
         expected_visit_statuses = [ovs1, visit_status1, visit_status1]
 
         # write twice in the journal
         expected_objects = (
             [("origin", o) for o in expected_origins]
             + [("origin_visit", v) for v in expected_visits]
             + [("origin_visit_status", ovs) for ovs in expected_visit_statuses]
         )
 
         for obj in expected_objects:
             assert obj in actual_objects
 
     def test_origin_visit_find_by_date(self, swh_storage, sample_data):
         origin = sample_data.origin
         swh_storage.origin_add([origin])
         visit1 = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit2,
             type=sample_data.type_visit1,
         )
         visit2 = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit3,
             type=sample_data.type_visit2,
         )
         visit3 = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit2,
             type=sample_data.type_visit3,
         )
         ov1, ov2, ov3 = swh_storage.origin_visit_add([visit1, visit2, visit3])
 
         ovs1 = OriginVisitStatus(
             origin=origin.url,
             visit=ov1.visit,
             date=sample_data.date_visit2,
             status="ongoing",
             snapshot=None,
         )
         ovs2 = OriginVisitStatus(
             origin=origin.url,
             visit=ov2.visit,
             date=sample_data.date_visit3,
             status="ongoing",
             snapshot=None,
         )
         ovs3 = OriginVisitStatus(
             origin=origin.url,
             visit=ov3.visit,
             date=sample_data.date_visit2,
             status="ongoing",
             snapshot=None,
         )
         swh_storage.origin_visit_status_add([ovs1, ovs2, ovs3])
 
         # Simple case
         visit = swh_storage.origin_visit_find_by_date(
             origin.url, sample_data.date_visit3
         )
         assert visit["visit"] == ov2.visit
 
         # There are two visits at the same date, the latest must be returned
         visit = swh_storage.origin_visit_find_by_date(
             origin.url, sample_data.date_visit2
         )
         assert visit["visit"] == ov3.visit
 
     def test_origin_visit_find_by_date__unknown_origin(self, swh_storage, sample_data):
         swh_storage.origin_visit_find_by_date("foo", sample_data.date_visit2)
 
     def test_origin_visit_get_by(self, swh_storage, sample_data):
         snapshot = sample_data.snapshot
         origins = sample_data.origins[:2]
         swh_storage.origin_add(origins)
         origin_url, origin_url2 = [o.url for o in origins]
 
         visit = OriginVisit(
             origin=origin_url,
             date=sample_data.date_visit2,
             type=sample_data.type_visit2,
         )
         origin_visit1 = swh_storage.origin_visit_add([visit])[0]
 
         swh_storage.snapshot_add([snapshot])
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin_url,
                     visit=origin_visit1.visit,
                     date=now(),
                     status="ongoing",
                     snapshot=snapshot.id,
                 )
             ]
         )
 
         # Add some other {origin, visit} entries
         visit2 = OriginVisit(
             origin=origin_url,
             date=sample_data.date_visit3,
             type=sample_data.type_visit3,
         )
         visit3 = OriginVisit(
             origin=origin_url2,
             date=sample_data.date_visit3,
             type=sample_data.type_visit3,
         )
         swh_storage.origin_visit_add([visit2, visit3])
 
         # when
         visit1_metadata = {
             "contents": 42,
             "directories": 22,
         }
 
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin_url,
                     visit=origin_visit1.visit,
                     date=now(),
                     status="full",
                     snapshot=snapshot.id,
                     metadata=visit1_metadata,
                 )
             ]
         )
 
         expected_origin_visit = origin_visit1.to_dict()
         expected_origin_visit.update(
             {
                 "origin": origin_url,
                 "visit": origin_visit1.visit,
                 "date": sample_data.date_visit2,
                 "type": sample_data.type_visit2,
                 "metadata": visit1_metadata,
                 "status": "full",
                 "snapshot": snapshot.id,
             }
         )
 
         # when
         actual_origin_visit1 = swh_storage.origin_visit_get_by(
             origin_url, origin_visit1.visit
         )
 
         # then
         assert actual_origin_visit1 == expected_origin_visit
 
     def test_origin_visit_get_by__unknown_origin(self, swh_storage):
         assert swh_storage.origin_visit_get_by("foo", 10) is None
 
     def test_origin_visit_get_by_no_result(self, swh_storage, sample_data):
         origin = sample_data.origin
         swh_storage.origin_add([origin])
         actual_origin_visit = swh_storage.origin_visit_get_by(origin.url, 999)
         assert actual_origin_visit is None
 
     def test_origin_visit_get_latest_none(self, swh_storage, sample_data):
         """Origin visit get latest on unknown objects should return nothing
 
         """
         # unknown origin so no result
         assert swh_storage.origin_visit_get_latest("unknown-origin") is None
 
         # unknown type
         origin = sample_data.origin
         swh_storage.origin_add([origin])
         assert swh_storage.origin_visit_get_latest(origin.url, type="unknown") is None
 
     def test_origin_visit_get_latest_filter_type(self, swh_storage, sample_data):
         """Filtering origin visit get latest with filter type should be ok
 
         """
         origin = sample_data.origin
         swh_storage.origin_add([origin])
         visit1 = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit1,
             type=sample_data.type_visit1,
         )
         visit2 = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit2,
             type=sample_data.type_visit2,
         )
         # Add a visit with the same date as the previous one
         visit3 = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit2,
             type=sample_data.type_visit2,
         )
         assert sample_data.type_visit1 != sample_data.type_visit2
         assert sample_data.date_visit1 < sample_data.date_visit2
 
         ov1, ov2, ov3 = swh_storage.origin_visit_add([visit1, visit2, visit3])
 
         origin_visit1 = swh_storage.origin_visit_get_by(origin.url, ov1.visit)
         origin_visit3 = swh_storage.origin_visit_get_by(origin.url, ov3.visit)
 
         assert sample_data.type_visit1 != sample_data.type_visit2
 
         # Check type filter is ok
         actual_ov1 = swh_storage.origin_visit_get_latest(
             origin.url, type=sample_data.type_visit1,
         )
         assert actual_ov1 == origin_visit1
 
         actual_ov3 = swh_storage.origin_visit_get_latest(
             origin.url, type=sample_data.type_visit2,
         )
         assert actual_ov3 == origin_visit3
 
         new_type = "npm"
         assert new_type not in [sample_data.type_visit1, sample_data.type_visit2]
 
         assert (
             swh_storage.origin_visit_get_latest(
                 origin.url, type=new_type,  # no visit matching that type
             )
             is None
         )
 
     def test_origin_visit_get_latest(self, swh_storage, sample_data):
         empty_snapshot, complete_snapshot = sample_data.snapshots[1:3]
         origin = sample_data.origin
 
         swh_storage.origin_add([origin])
         visit1 = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit1,
             type=sample_data.type_visit1,
         )
         visit2 = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit2,
             type=sample_data.type_visit2,
         )
         # Add a visit with the same date as the previous one
         visit3 = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit2,
             type=sample_data.type_visit2,
         )
 
         ov1, ov2, ov3 = swh_storage.origin_visit_add([visit1, visit2, visit3])
 
         origin_visit1 = swh_storage.origin_visit_get_by(origin.url, ov1.visit)
         origin_visit2 = swh_storage.origin_visit_get_by(origin.url, ov2.visit)
         origin_visit3 = swh_storage.origin_visit_get_by(origin.url, ov3.visit)
         # Two visits, both with no snapshot
         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
 
         swh_storage.snapshot_add([complete_snapshot])
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=ov1.visit,
                     date=now(),
                     status="ongoing",
                     snapshot=complete_snapshot.id,
                 )
             ]
         )
         actual_visit = swh_storage.origin_visit_get_latest(
             origin.url, require_snapshot=True
         )
         assert actual_visit == {
             **origin_visit1,
             "snapshot": complete_snapshot.id,
             "status": "ongoing",  # visit1 has status created now
         }
 
         assert origin_visit3 == swh_storage.origin_visit_get_latest(origin.url)
 
         # Status filter: all three visits are status=ongoing, so no visit
         # returned
         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
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=ov1.visit,
                     date=now(),
                     status="full",
                     snapshot=complete_snapshot.id,
                 )
             ]
         )
 
         assert {
             **origin_visit1,
             "snapshot": 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
         swh_storage.snapshot_add([empty_snapshot])
 
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=ov2.visit,
                     date=now(),
                     status="ongoing",
                     snapshot=empty_snapshot.id,
                 )
             ]
         )
         assert {
             **origin_visit2,
             "snapshot": empty_snapshot.id,
             "status": "ongoing",
         } == 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
         assert {
             **origin_visit1,
             "snapshot": complete_snapshot.id,
             "status": "full",
         } == swh_storage.origin_visit_get_latest(origin.url, allowed_statuses=["full"])
 
         # Add snapshot to visit3 (same date as visit2)
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=ov3.visit,
                     date=now(),
                     status="ongoing",
                     snapshot=complete_snapshot.id,
                 )
             ]
         )
         assert {
             **origin_visit1,
             "snapshot": complete_snapshot.id,
             "status": "full",
         } == swh_storage.origin_visit_get_latest(origin.url, allowed_statuses=["full"])
         assert {
             **origin_visit1,
             "snapshot": complete_snapshot.id,
             "status": "full",
         } == swh_storage.origin_visit_get_latest(
             origin.url, allowed_statuses=["full"], require_snapshot=True
         )
         assert {
             **origin_visit3,
             "snapshot": complete_snapshot.id,
             "status": "ongoing",
         } == swh_storage.origin_visit_get_latest(origin.url)
 
         assert {
             **origin_visit3,
             "snapshot": complete_snapshot.id,
             "status": "ongoing",
         } == swh_storage.origin_visit_get_latest(origin.url, require_snapshot=True)
 
     def test_origin_visit_status_get_latest(self, swh_storage, sample_data):
         snapshot = sample_data.snapshots[2]
         origin1 = sample_data.origin
         swh_storage.origin_add([origin1])
 
         # to have some reference visits
 
         ov1, ov2 = swh_storage.origin_visit_add(
             [
                 OriginVisit(
                     origin=origin1.url,
                     date=sample_data.date_visit1,
                     type=sample_data.type_visit1,
                 ),
                 OriginVisit(
                     origin=origin1.url,
                     date=sample_data.date_visit2,
                     type=sample_data.type_visit2,
                 ),
             ]
         )
         swh_storage.snapshot_add([snapshot])
 
         date_now = now()
         date_now = round_to_milliseconds(date_now)
         assert sample_data.date_visit1 < sample_data.date_visit2
         assert sample_data.date_visit2 < date_now
 
         ovs1 = OriginVisitStatus(
             origin=origin1.url,
             visit=ov1.visit,
             date=sample_data.date_visit1,
             status="partial",
             snapshot=None,
         )
         ovs2 = OriginVisitStatus(
             origin=origin1.url,
             visit=ov1.visit,
             date=sample_data.date_visit2,
             status="ongoing",
             snapshot=None,
         )
         ovs3 = OriginVisitStatus(
             origin=origin1.url,
             visit=ov2.visit,
             date=sample_data.date_visit2
             + datetime.timedelta(minutes=1),  # to not be ignored
             status="ongoing",
             snapshot=None,
         )
         ovs4 = OriginVisitStatus(
             origin=origin1.url,
             visit=ov2.visit,
             date=date_now,
             status="full",
             snapshot=snapshot.id,
             metadata={"something": "wicked"},
         )
 
         swh_storage.origin_visit_status_add([ovs1, ovs2, ovs3, ovs4])
 
         # unknown origin so no result
         actual_origin_visit = swh_storage.origin_visit_status_get_latest(
             "unknown-origin", ov1.visit
         )
         assert actual_origin_visit is None
 
         # unknown visit so no result
         actual_origin_visit = swh_storage.origin_visit_status_get_latest(
             ov1.origin, ov1.visit + 10
         )
         assert actual_origin_visit is None
 
         # Two visits, both with no snapshot, take the most recent
         actual_origin_visit2 = swh_storage.origin_visit_status_get_latest(
             origin1.url, ov1.visit
         )
         assert isinstance(actual_origin_visit2, OriginVisitStatus)
         assert actual_origin_visit2 == ovs2
         assert ovs2.origin == origin1.url
         assert ovs2.visit == ov1.visit
 
         actual_origin_visit = swh_storage.origin_visit_status_get_latest(
             origin1.url, ov1.visit, require_snapshot=True
         )
         # there is no visit with snapshot yet for that visit
         assert actual_origin_visit is None
 
         actual_origin_visit2 = swh_storage.origin_visit_status_get_latest(
             origin1.url, ov1.visit, allowed_statuses=["partial", "ongoing"]
         )
         # visit status with partial status visit elected
         assert actual_origin_visit2 == ovs2
         assert actual_origin_visit2.status == "ongoing"
 
         actual_origin_visit4 = swh_storage.origin_visit_status_get_latest(
             origin1.url, ov2.visit, require_snapshot=True
         )
         assert actual_origin_visit4 == ovs4
         assert actual_origin_visit4.snapshot == snapshot.id
 
         actual_origin_visit = swh_storage.origin_visit_status_get_latest(
             origin1.url, ov2.visit, require_snapshot=True, allowed_statuses=["ongoing"]
         )
         # nothing matches so nothing
         assert actual_origin_visit is None  # there is no visit with status full
 
         actual_origin_visit3 = swh_storage.origin_visit_status_get_latest(
             origin1.url, ov2.visit, allowed_statuses=["ongoing"]
         )
         assert actual_origin_visit3 == ovs3
 
     def test_person_fullname_unicity(self, swh_storage, sample_data):
         revision, rev2 = sample_data.revisions[0:2]
         # create a revision with same committer fullname but wo name and email
         revision2 = attr.evolve(
             rev2,
             committer=Person(
                 fullname=revision.committer.fullname, name=None, email=None
             ),
         )
 
         swh_storage.revision_add([revision, revision2])
 
         # when getting added revisions
         revisions = list(swh_storage.revision_get([revision.id, revision2.id]))
 
         # then check committers are the same
         assert revisions[0]["committer"] == revisions[1]["committer"]
 
     def test_snapshot_add_get_empty(self, swh_storage, sample_data):
         empty_snapshot = sample_data.snapshots[1]
         empty_snapshot_dict = empty_snapshot.to_dict()
 
         origin = sample_data.origin
         swh_storage.origin_add([origin])
         ov1 = swh_storage.origin_visit_add(
             [
                 OriginVisit(
                     origin=origin.url,
                     date=sample_data.date_visit1,
                     type=sample_data.type_visit1,
                 )
             ]
         )[0]
 
         actual_result = swh_storage.snapshot_add([empty_snapshot])
         assert actual_result == {"snapshot:add": 1}
 
         date_now = now()
 
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=ov1.visit,
                     date=date_now,
                     status="full",
                     snapshot=empty_snapshot.id,
                 )
             ]
         )
 
         by_id = swh_storage.snapshot_get(empty_snapshot.id)
         assert by_id == {**empty_snapshot_dict, "next_branch": None}
 
         by_ov = swh_storage.snapshot_get_by_origin_visit(origin.url, ov1.visit)
         assert by_ov == {**empty_snapshot_dict, "next_branch": None}
 
         ovs1 = OriginVisitStatus.from_dict(
             {
                 "origin": origin.url,
                 "date": sample_data.date_visit1,
                 "visit": ov1.visit,
                 "status": "created",
                 "snapshot": None,
                 "metadata": None,
             }
         )
         ovs2 = OriginVisitStatus.from_dict(
             {
                 "origin": origin.url,
                 "date": date_now,
                 "visit": ov1.visit,
                 "status": "full",
                 "metadata": None,
                 "snapshot": empty_snapshot.id,
             }
         )
         actual_objects = list(swh_storage.journal_writer.journal.objects)
 
         expected_objects = [
             ("origin", origin),
             ("origin_visit", ov1),
             ("origin_visit_status", ovs1,),
             ("snapshot", empty_snapshot),
             ("origin_visit_status", ovs2,),
         ]
         for obj in expected_objects:
             assert obj in actual_objects
 
     def test_snapshot_add_get_complete(self, swh_storage, sample_data):
         complete_snapshot = sample_data.snapshots[2]
         complete_snapshot_dict = complete_snapshot.to_dict()
         origin = sample_data.origin
 
         swh_storage.origin_add([origin])
         visit = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit1,
             type=sample_data.type_visit1,
         )
         origin_visit1 = swh_storage.origin_visit_add([visit])[0]
         visit_id = origin_visit1.visit
 
         actual_result = swh_storage.snapshot_add([complete_snapshot])
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=origin_visit1.visit,
                     date=now(),
                     status="ongoing",
                     snapshot=complete_snapshot.id,
                 )
             ]
         )
         assert actual_result == {"snapshot:add": 1}
 
         by_id = swh_storage.snapshot_get(complete_snapshot.id)
         assert by_id == {**complete_snapshot_dict, "next_branch": None}
 
         by_ov = swh_storage.snapshot_get_by_origin_visit(origin.url, visit_id)
         assert by_ov == {**complete_snapshot_dict, "next_branch": None}
 
     def test_snapshot_add_many(self, swh_storage, sample_data):
         snapshot, _, complete_snapshot = sample_data.snapshots[:3]
 
         actual_result = swh_storage.snapshot_add([snapshot, complete_snapshot])
         assert actual_result == {"snapshot:add": 2}
 
         assert swh_storage.snapshot_get(complete_snapshot.id) == {
             **complete_snapshot.to_dict(),
             "next_branch": None,
         }
 
         assert swh_storage.snapshot_get(snapshot.id) == {
             **snapshot.to_dict(),
             "next_branch": None,
         }
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["snapshot"] == 2
 
     def test_snapshot_add_many_from_generator(self, swh_storage, sample_data):
         snapshot, _, complete_snapshot = sample_data.snapshots[:3]
 
         def _snp_gen():
             yield from [snapshot, complete_snapshot]
 
         actual_result = swh_storage.snapshot_add(_snp_gen())
         assert actual_result == {"snapshot:add": 2}
 
         swh_storage.refresh_stat_counters()
         assert swh_storage.stat_counters()["snapshot"] == 2
 
     def test_snapshot_add_many_incremental(self, swh_storage, sample_data):
         snapshot, _, complete_snapshot = sample_data.snapshots[:3]
 
         actual_result = swh_storage.snapshot_add([complete_snapshot])
         assert actual_result == {"snapshot:add": 1}
 
         actual_result2 = swh_storage.snapshot_add([snapshot, complete_snapshot])
         assert actual_result2 == {"snapshot:add": 1}
 
         assert swh_storage.snapshot_get(complete_snapshot.id) == {
             **complete_snapshot.to_dict(),
             "next_branch": None,
         }
 
         assert swh_storage.snapshot_get(snapshot.id) == {
             **snapshot.to_dict(),
             "next_branch": None,
         }
 
     def test_snapshot_add_twice(self, swh_storage, sample_data):
         snapshot, empty_snapshot = sample_data.snapshots[:2]
 
         actual_result = swh_storage.snapshot_add([empty_snapshot])
         assert actual_result == {"snapshot:add": 1}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("snapshot", empty_snapshot)
         ]
 
         actual_result = swh_storage.snapshot_add([snapshot])
         assert actual_result == {"snapshot:add": 1}
 
         assert list(swh_storage.journal_writer.journal.objects) == [
             ("snapshot", empty_snapshot),
             ("snapshot", snapshot),
         ]
 
     def test_snapshot_add_count_branches(self, swh_storage, sample_data):
         complete_snapshot = sample_data.snapshots[2]
 
         actual_result = swh_storage.snapshot_add([complete_snapshot])
         assert actual_result == {"snapshot:add": 1}
 
         snp_size = swh_storage.snapshot_count_branches(complete_snapshot.id)
 
         expected_snp_size = {
             "alias": 1,
             "content": 1,
             "directory": 2,
             "release": 1,
             "revision": 1,
             "snapshot": 1,
             None: 1,
         }
         assert snp_size == expected_snp_size
 
     def test_snapshot_add_get_paginated(self, swh_storage, sample_data):
         complete_snapshot = sample_data.snapshots[2]
 
         swh_storage.snapshot_add([complete_snapshot])
 
         snp_id = complete_snapshot.id
         branches = complete_snapshot.to_dict()["branches"]
         branch_names = list(sorted(branches))
 
         # Test branch_from
         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,
         }
 
         assert snapshot == expected_snapshot
 
         # Test branches_count
         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",
         }
         assert snapshot == expected_snapshot
 
         # test branch_from + branches_count
 
         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],
         }
 
         assert snapshot == expected_snapshot
 
     def test_snapshot_add_get_filtered(self, swh_storage, sample_data):
         origin = sample_data.origin
         complete_snapshot = sample_data.snapshots[2]
 
         swh_storage.origin_add([origin])
         visit = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit1,
             type=sample_data.type_visit1,
         )
         origin_visit1 = swh_storage.origin_visit_add([visit])[0]
 
         swh_storage.snapshot_add([complete_snapshot])
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=origin_visit1.visit,
                     date=now(),
                     status="ongoing",
                     snapshot=complete_snapshot.id,
                 )
             ]
         )
 
         snp_id = complete_snapshot.id
         branches = complete_snapshot.to_dict()["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,
         }
 
         assert snapshot == expected_snapshot
 
         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,
         }
 
         assert snapshot == expected_snapshot
 
     def test_snapshot_add_get_filtered_and_paginated(self, swh_storage, sample_data):
         complete_snapshot = sample_data.snapshots[2]
 
         swh_storage.snapshot_add([complete_snapshot])
 
         snp_id = complete_snapshot.id
         branches = complete_snapshot.to_dict()["branches"]
         branch_names = list(sorted(branches))
 
         # Test branch_from
 
         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,
         }
 
         assert snapshot == expected_snapshot
 
         # Test branches_count
 
         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",
         }
         assert snapshot == expected_snapshot
 
         # Test branches_count
 
         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",
         }
         assert snapshot == expected_snapshot
 
         # test branch_from + branches_count
 
         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",
         }
 
         assert snapshot == expected_snapshot
 
     def test_snapshot_add_get_branch_by_type(self, swh_storage, sample_data):
         complete_snapshot = sample_data.snapshots[2]
         snapshot = complete_snapshot.to_dict()
 
         alias1 = b"alias1"
         alias2 = b"alias2"
         target1 = random.choice(list(snapshot["branches"].keys()))
         target2 = random.choice(list(snapshot["branches"].keys()))
 
         snapshot["branches"][alias2] = {
             "target": target2,
             "target_type": "alias",
         }
 
         snapshot["branches"][alias1] = {
             "target": target1,
             "target_type": "alias",
         }
 
         new_snapshot = Snapshot.from_dict(snapshot)
         swh_storage.snapshot_add([new_snapshot])
 
         branches = swh_storage.snapshot_get_branches(
             new_snapshot.id,
             target_types=["alias"],
             branches_from=alias1,
             branches_count=1,
         )["branches"]
 
         assert len(branches) == 1
         assert alias1 in branches
 
     def test_snapshot_add_get(self, swh_storage, sample_data):
         snapshot = sample_data.snapshot
         origin = sample_data.origin
 
         swh_storage.origin_add([origin])
         visit = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit1,
             type=sample_data.type_visit1,
         )
         origin_visit1 = swh_storage.origin_visit_add([visit])[0]
         visit_id = origin_visit1.visit
 
         swh_storage.snapshot_add([snapshot])
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=origin_visit1.visit,
                     date=now(),
                     status="ongoing",
                     snapshot=snapshot.id,
                 )
             ]
         )
 
         expected_snapshot = {**snapshot.to_dict(), "next_branch": None}
 
         by_id = swh_storage.snapshot_get(snapshot.id)
         assert by_id == expected_snapshot
 
         by_ov = swh_storage.snapshot_get_by_origin_visit(origin.url, visit_id)
         assert by_ov == expected_snapshot
 
         origin_visit_info = swh_storage.origin_visit_get_by(origin.url, visit_id)
         assert origin_visit_info["snapshot"] == snapshot.id
 
     def test_snapshot_add_twice__by_origin_visit(self, swh_storage, sample_data):
         snapshot = sample_data.snapshot
         origin = sample_data.origin
 
         swh_storage.origin_add([origin])
         ov1 = swh_storage.origin_visit_add(
             [
                 OriginVisit(
                     origin=origin.url,
                     date=sample_data.date_visit1,
                     type=sample_data.type_visit1,
                 )
             ]
         )[0]
         swh_storage.snapshot_add([snapshot])
         date_now2 = now()
 
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=ov1.visit,
                     date=date_now2,
                     status="ongoing",
                     snapshot=snapshot.id,
                 )
             ]
         )
 
         expected_snapshot = {**snapshot.to_dict(), "next_branch": None}
 
         by_ov1 = swh_storage.snapshot_get_by_origin_visit(origin.url, ov1.visit)
         assert by_ov1 == expected_snapshot
 
         ov2 = swh_storage.origin_visit_add(
             [
                 OriginVisit(
                     origin=origin.url,
                     date=sample_data.date_visit2,
                     type=sample_data.type_visit2,
                 )
             ]
         )[0]
 
         date_now4 = now()
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=ov2.visit,
                     date=date_now4,
                     status="ongoing",
                     snapshot=snapshot.id,
                 )
             ]
         )
 
         by_ov2 = swh_storage.snapshot_get_by_origin_visit(origin.url, ov2.visit)
         assert by_ov2 == expected_snapshot
 
         ovs1 = OriginVisitStatus.from_dict(
             {
                 "origin": origin.url,
                 "date": sample_data.date_visit1,
                 "visit": ov1.visit,
                 "status": "created",
                 "metadata": None,
                 "snapshot": None,
             }
         )
         ovs2 = OriginVisitStatus.from_dict(
             {
                 "origin": origin.url,
                 "date": date_now2,
                 "visit": ov1.visit,
                 "status": "ongoing",
                 "metadata": None,
                 "snapshot": snapshot.id,
             }
         )
         ovs3 = OriginVisitStatus.from_dict(
             {
                 "origin": origin.url,
                 "date": sample_data.date_visit2,
                 "visit": ov2.visit,
                 "status": "created",
                 "metadata": None,
                 "snapshot": None,
             }
         )
         ovs4 = OriginVisitStatus.from_dict(
             {
                 "origin": origin.url,
                 "date": date_now4,
                 "visit": ov2.visit,
                 "status": "ongoing",
                 "metadata": None,
                 "snapshot": snapshot.id,
             }
         )
         actual_objects = list(swh_storage.journal_writer.journal.objects)
         expected_objects = [
             ("origin", origin),
             ("origin_visit", ov1),
             ("origin_visit_status", ovs1),
             ("snapshot", snapshot),
             ("origin_visit_status", ovs2),
             ("origin_visit", ov2),
             ("origin_visit_status", ovs3),
             ("origin_visit_status", ovs4),
         ]
 
         for obj in expected_objects:
             assert obj in actual_objects
 
     def test_snapshot_get_random(self, swh_storage, sample_data):
         snapshot, empty_snapshot, complete_snapshot = sample_data.snapshots[:3]
         swh_storage.snapshot_add([snapshot, empty_snapshot, complete_snapshot])
 
         assert swh_storage.snapshot_get_random() in {
             snapshot.id,
             empty_snapshot.id,
             complete_snapshot.id,
         }
 
     def test_snapshot_missing(self, swh_storage, sample_data):
         snapshot, missing_snapshot = sample_data.snapshots[:2]
         snapshots = [snapshot.id, missing_snapshot.id]
         swh_storage.snapshot_add([snapshot])
 
         missing_snapshots = swh_storage.snapshot_missing(snapshots)
 
         assert list(missing_snapshots) == [missing_snapshot.id]
 
     def test_stat_counters(self, swh_storage, sample_data):
         origin = sample_data.origin
         snapshot = sample_data.snapshot
         revision = sample_data.revision
         release = sample_data.release
         directory = sample_data.directory
         content = sample_data.content
 
         expected_keys = ["content", "directory", "origin", "revision"]
 
         # Initially, all counters are 0
 
         swh_storage.refresh_stat_counters()
         counters = swh_storage.stat_counters()
         assert set(expected_keys) <= set(counters)
         for key in expected_keys:
             assert counters[key] == 0
 
         # Add a content. Only the content counter should increase.
 
         swh_storage.content_add([content])
 
         swh_storage.refresh_stat_counters()
         counters = swh_storage.stat_counters()
 
         assert set(expected_keys) <= set(counters)
         for key in expected_keys:
             if key != "content":
                 assert counters[key] == 0
         assert counters["content"] == 1
 
         # Add other objects. Check their counter increased as well.
 
         swh_storage.origin_add([origin])
         visit = OriginVisit(
             origin=origin.url,
             date=sample_data.date_visit2,
             type=sample_data.type_visit2,
         )
         origin_visit1 = swh_storage.origin_visit_add([visit])[0]
 
         swh_storage.snapshot_add([snapshot])
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin.url,
                     visit=origin_visit1.visit,
                     date=now(),
                     status="ongoing",
                     snapshot=snapshot.id,
                 )
             ]
         )
         swh_storage.directory_add([directory])
         swh_storage.revision_add([revision])
         swh_storage.release_add([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:
             assert counters["person"] == 3
 
     def test_content_find_ctime(self, swh_storage, sample_data):
         origin_content = sample_data.content
         ctime = round_to_milliseconds(now())
         content = attr.evolve(origin_content, data=None, ctime=ctime)
         swh_storage.content_add_metadata([content])
 
         actually_present = swh_storage.content_find({"sha1": content.sha1})
         assert actually_present[0] == content.to_dict()
 
     def test_content_find_with_present_content(self, swh_storage, sample_data):
         content = sample_data.content
         expected_content = content.to_dict()
         del expected_content["data"]
         del expected_content["ctime"]
 
         # 1. with something to find
         swh_storage.content_add([content])
 
         actually_present = swh_storage.content_find({"sha1": content.sha1})
         assert 1 == len(actually_present)
         actually_present[0].pop("ctime")
         assert actually_present[0] == expected_content
 
         # 2. with something to find
         actually_present = swh_storage.content_find({"sha1_git": content.sha1_git})
         assert 1 == len(actually_present)
         actually_present[0].pop("ctime")
         assert actually_present[0] == expected_content
 
         # 3. with something to find
         actually_present = swh_storage.content_find({"sha256": content.sha256})
         assert 1 == len(actually_present)
         actually_present[0].pop("ctime")
         assert actually_present[0] == expected_content
 
         # 4. with something to find
         actually_present = swh_storage.content_find(content.hashes())
         assert 1 == len(actually_present)
         actually_present[0].pop("ctime")
         assert actually_present[0] == expected_content
 
     def test_content_find_with_non_present_content(self, swh_storage, sample_data):
         missing_content = sample_data.skipped_content
         # 1. with something that does not exist
         actually_present = swh_storage.content_find({"sha1": missing_content.sha1})
 
         assert actually_present == []
 
         # 2. with something that does not exist
         actually_present = swh_storage.content_find(
             {"sha1_git": missing_content.sha1_git}
         )
         assert actually_present == []
 
         # 3. with something that does not exist
         actually_present = swh_storage.content_find({"sha256": missing_content.sha256})
         assert actually_present == []
 
     def test_content_find_with_duplicate_input(self, swh_storage, sample_data):
         content = sample_data.content
 
         # Create fake data with colliding sha256 and blake2s256
         sha1_array = bytearray(content.sha1)
         sha1_array[0] += 1
         sha1git_array = bytearray(content.sha1_git)
         sha1git_array[0] += 1
         duplicated_content = attr.evolve(
             content, sha1=bytes(sha1_array), sha1_git=bytes(sha1git_array)
         )
 
         # Inject the data
         swh_storage.content_add([content, duplicated_content])
 
         actual_result = list(
             swh_storage.content_find(
                 {
                     "blake2s256": duplicated_content.blake2s256,
                     "sha256": duplicated_content.sha256,
                 }
             )
         )
 
         expected_content = content.to_dict()
         expected_duplicated_content = duplicated_content.to_dict()
 
         for key in ["data", "ctime"]:  # so we can compare
             for dict_ in [
                 expected_content,
                 expected_duplicated_content,
                 actual_result[0],
                 actual_result[1],
             ]:
                 dict_.pop(key, None)
 
         expected_result = [expected_content, expected_duplicated_content]
         for result in expected_result:
             assert result in actual_result
 
     def test_content_find_with_duplicate_sha256(self, swh_storage, sample_data):
         content = sample_data.content
 
         hashes = {}
         # Create fake data with colliding sha256
         for hashalgo in ("sha1", "sha1_git", "blake2s256"):
             value = bytearray(getattr(content, hashalgo))
             value[0] += 1
             hashes[hashalgo] = bytes(value)
 
         duplicated_content = attr.evolve(
             content,
             sha1=hashes["sha1"],
             sha1_git=hashes["sha1_git"],
             blake2s256=hashes["blake2s256"],
         )
         swh_storage.content_add([content, duplicated_content])
 
         actual_result = list(
             swh_storage.content_find({"sha256": duplicated_content.sha256})
         )
 
         assert len(actual_result) == 2
 
         expected_content = content.to_dict()
         expected_duplicated_content = duplicated_content.to_dict()
 
         for key in ["data", "ctime"]:  # so we can compare
             for dict_ in [
                 expected_content,
                 expected_duplicated_content,
                 actual_result[0],
                 actual_result[1],
             ]:
                 dict_.pop(key, None)
 
         assert sorted(actual_result, key=lambda x: x["sha1"]) == [
             expected_content,
             expected_duplicated_content,
         ]
 
         # Find with both sha256 and blake2s256
         actual_result = list(
             swh_storage.content_find(
                 {
                     "sha256": duplicated_content.sha256,
                     "blake2s256": duplicated_content.blake2s256,
                 }
             )
         )
 
         assert len(actual_result) == 1
         actual_result[0].pop("ctime")
 
         assert actual_result == [expected_duplicated_content]
 
     def test_content_find_with_duplicate_blake2s256(self, swh_storage, sample_data):
         content = sample_data.content
 
         # Create fake data with colliding sha256 and blake2s256
         sha1_array = bytearray(content.sha1)
         sha1_array[0] += 1
         sha1git_array = bytearray(content.sha1_git)
         sha1git_array[0] += 1
         sha256_array = bytearray(content.sha256)
         sha256_array[0] += 1
 
         duplicated_content = attr.evolve(
             content,
             sha1=bytes(sha1_array),
             sha1_git=bytes(sha1git_array),
             sha256=bytes(sha256_array),
         )
 
         swh_storage.content_add([content, duplicated_content])
 
         actual_result = list(
             swh_storage.content_find({"blake2s256": duplicated_content.blake2s256})
         )
 
         expected_content = content.to_dict()
         expected_duplicated_content = duplicated_content.to_dict()
 
         for key in ["data", "ctime"]:  # so we can compare
             for dict_ in [
                 expected_content,
                 expected_duplicated_content,
                 actual_result[0],
                 actual_result[1],
             ]:
                 dict_.pop(key, None)
 
         expected_result = [expected_content, expected_duplicated_content]
         for result in expected_result:
             assert result in actual_result
 
         # Find with both sha256 and blake2s256
         actual_result = list(
             swh_storage.content_find(
                 {
                     "sha256": duplicated_content.sha256,
                     "blake2s256": duplicated_content.blake2s256,
                 }
             )
         )
 
         actual_result[0].pop("ctime")
         assert actual_result == [expected_duplicated_content]
 
     def test_content_find_bad_input(self, swh_storage):
         # 1. with bad input
         with pytest.raises(StorageArgumentException):
             swh_storage.content_find({})  # empty is bad
 
         # 2. with bad input
         with pytest.raises(StorageArgumentException):
             swh_storage.content_find({"unknown-sha1": "something"})  # not the right key
 
     def test_object_find_by_sha1_git(self, swh_storage, sample_data):
         content = sample_data.content
         directory = sample_data.directory
         revision = sample_data.revision
         release = sample_data.release
 
         sha1_gits = [b"00000000000000000000"]
         expected = {
             b"00000000000000000000": [],
         }
 
         swh_storage.content_add([content])
         sha1_gits.append(content.sha1_git)
 
         expected[content.sha1_git] = [
             {"sha1_git": content.sha1_git, "type": "content",}
         ]
 
         swh_storage.directory_add([directory])
         sha1_gits.append(directory.id)
         expected[directory.id] = [{"sha1_git": directory.id, "type": "directory",}]
 
         swh_storage.revision_add([revision])
         sha1_gits.append(revision.id)
         expected[revision.id] = [{"sha1_git": revision.id, "type": "revision",}]
 
         swh_storage.release_add([release])
         sha1_gits.append(release.id)
         expected[release.id] = [{"sha1_git": release.id, "type": "release",}]
 
         ret = swh_storage.object_find_by_sha1_git(sha1_gits)
 
         assert expected == ret
 
     def test_metadata_fetcher_add_get(self, swh_storage, sample_data):
         fetcher = sample_data.metadata_fetcher
         actual_fetcher = swh_storage.metadata_fetcher_get(fetcher.name, fetcher.version)
         assert actual_fetcher is None  # does not exist
 
         swh_storage.metadata_fetcher_add([fetcher])
 
         res = swh_storage.metadata_fetcher_get(fetcher.name, fetcher.version)
         assert res == fetcher
 
+    def test_metadata_fetcher_add_zero(self, swh_storage, sample_data):
+        fetcher = sample_data.metadata_fetcher
+        actual_fetcher = swh_storage.metadata_fetcher_get(fetcher.name, fetcher.version)
+        assert actual_fetcher is None  # does not exist
+
+        swh_storage.metadata_fetcher_add([])
+
     def test_metadata_authority_add_get(self, swh_storage, sample_data):
         authority = sample_data.metadata_authority
 
         actual_authority = swh_storage.metadata_authority_get(
             authority.type, authority.url
         )
         assert actual_authority is None  # does not exist
 
         swh_storage.metadata_authority_add([authority])
 
         res = swh_storage.metadata_authority_get(authority.type, authority.url)
         assert res == authority
 
+    def test_metadata_authority_add_zero(self, swh_storage, sample_data):
+        authority = sample_data.metadata_authority
+
+        actual_authority = swh_storage.metadata_authority_get(
+            authority.type, authority.url
+        )
+        assert actual_authority is None  # does not exist
+
+        swh_storage.metadata_authority_add([])
+
     def test_content_metadata_add(self, swh_storage, sample_data):
         content = sample_data.content
         fetcher = sample_data.metadata_fetcher
         authority = sample_data.metadata_authority
         content_metadata = sample_data.content_metadata[:2]
 
         content_swhid = SWHID(
             object_type="content", object_id=hash_to_bytes(content.sha1_git)
         )
 
         swh_storage.metadata_fetcher_add([fetcher])
         swh_storage.metadata_authority_add([authority])
 
         swh_storage.object_metadata_add(content_metadata)
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT, content_swhid, authority
         )
         assert result["next_page_token"] is None
         assert list(sorted(result["results"], key=lambda x: x.discovery_date,)) == list(
             content_metadata
         )
 
     def test_content_metadata_add_duplicate(self, swh_storage, sample_data):
         """Duplicates should be silently updated."""
         content = sample_data.content
         fetcher = sample_data.metadata_fetcher
         authority = sample_data.metadata_authority
         content_metadata, content_metadata2 = sample_data.content_metadata[:2]
         content_swhid = SWHID(
             object_type="content", object_id=hash_to_bytes(content.sha1_git)
         )
 
         new_content_metadata2 = attr.evolve(
             content_metadata2, format="new-format", metadata=b"new-metadata",
         )
 
         swh_storage.metadata_fetcher_add([fetcher])
         swh_storage.metadata_authority_add([authority])
 
         swh_storage.object_metadata_add([content_metadata, content_metadata2])
         swh_storage.object_metadata_add([new_content_metadata2])
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT, content_swhid, authority
         )
         assert result["next_page_token"] is None
 
         expected_results1 = (content_metadata, new_content_metadata2)
         expected_results2 = (content_metadata, content_metadata2)
 
         assert tuple(sorted(result["results"], key=lambda x: x.discovery_date,)) in (
             expected_results1,  # cassandra
             expected_results2,  # postgresql
         )
 
     def test_content_metadata_get(self, swh_storage, sample_data):
         content, content2 = sample_data.contents[:2]
         fetcher, fetcher2 = sample_data.fetchers[:2]
         authority, authority2 = sample_data.authorities[:2]
         (
             content1_metadata1,
             content1_metadata2,
             content1_metadata3,
         ) = sample_data.content_metadata[:3]
 
         content1_swhid = SWHID(object_type="content", object_id=content.sha1_git)
         content2_swhid = SWHID(object_type="content", object_id=content2.sha1_git)
         content2_metadata = attr.evolve(content1_metadata2, id=content2_swhid)
 
         swh_storage.metadata_authority_add([authority, authority2])
         swh_storage.metadata_fetcher_add([fetcher, fetcher2])
 
         swh_storage.object_metadata_add(
             [
                 content1_metadata1,
                 content1_metadata2,
                 content1_metadata3,
                 content2_metadata,
             ]
         )
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT, content1_swhid, authority
         )
         assert result["next_page_token"] is None
         assert [content1_metadata1, content1_metadata2] == list(
             sorted(result["results"], key=lambda x: x.discovery_date,)
         )
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT, content1_swhid, authority2
         )
         assert result["next_page_token"] is None
         assert [content1_metadata3] == list(
             sorted(result["results"], key=lambda x: x.discovery_date,)
         )
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT, content2_swhid, authority
         )
         assert result["next_page_token"] is None
         assert [content2_metadata] == list(result["results"],)
 
     def test_content_metadata_get_after(self, swh_storage, sample_data):
         content = sample_data.content
         fetcher = sample_data.metadata_fetcher
         authority = sample_data.metadata_authority
         content_metadata, content_metadata2 = sample_data.content_metadata[:2]
 
         content_swhid = SWHID(object_type="content", object_id=content.sha1_git)
 
         swh_storage.metadata_fetcher_add([fetcher])
         swh_storage.metadata_authority_add([authority])
 
         swh_storage.object_metadata_add([content_metadata, content_metadata2])
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT,
             content_swhid,
             authority,
             after=content_metadata.discovery_date - timedelta(seconds=1),
         )
         assert result["next_page_token"] is None
         assert [content_metadata, content_metadata2] == list(
             sorted(result["results"], key=lambda x: x.discovery_date,)
         )
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT,
             content_swhid,
             authority,
             after=content_metadata.discovery_date,
         )
         assert result["next_page_token"] is None
         assert result["results"] == [content_metadata2]
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT,
             content_swhid,
             authority,
             after=content_metadata2.discovery_date,
         )
         assert result["next_page_token"] is None
         assert result["results"] == []
 
     def test_content_metadata_get_paginate(self, swh_storage, sample_data):
         content = sample_data.content
         fetcher = sample_data.metadata_fetcher
         authority = sample_data.metadata_authority
         content_metadata, content_metadata2 = sample_data.content_metadata[:2]
 
         content_swhid = SWHID(object_type="content", object_id=content.sha1_git)
 
         swh_storage.metadata_fetcher_add([fetcher])
         swh_storage.metadata_authority_add([authority])
         swh_storage.object_metadata_add([content_metadata, content_metadata2])
         swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT, content_swhid, authority
         )
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT, content_swhid, authority, limit=1
         )
         assert result["next_page_token"] is not None
         assert result["results"] == [content_metadata]
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT,
             content_swhid,
             authority,
             limit=1,
             page_token=result["next_page_token"],
         )
         assert result["next_page_token"] is None
         assert result["results"] == [content_metadata2]
 
     def test_content_metadata_get_paginate_same_date(self, swh_storage, sample_data):
         content = sample_data.content
         fetcher1, fetcher2 = sample_data.fetchers[:2]
         authority = sample_data.metadata_authority
         content_metadata, content_metadata2 = sample_data.content_metadata[:2]
 
         content_swhid = SWHID(object_type="content", object_id=content.sha1_git)
 
         swh_storage.metadata_fetcher_add([fetcher1, fetcher2])
         swh_storage.metadata_authority_add([authority])
 
         new_content_metadata2 = attr.evolve(
             content_metadata2,
             discovery_date=content_metadata2.discovery_date,
             fetcher=attr.evolve(fetcher2, metadata=None),
         )
 
         swh_storage.object_metadata_add([content_metadata, new_content_metadata2])
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT, content_swhid, authority, limit=1
         )
         assert result["next_page_token"] is not None
         assert result["results"] == [content_metadata]
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.CONTENT,
             content_swhid,
             authority,
             limit=1,
             page_token=result["next_page_token"],
         )
         assert result["next_page_token"] is None
         assert result["results"] == [new_content_metadata2]
 
     def test_content_metadata_get__invalid_id(self, swh_storage, sample_data):
         origin = sample_data.origin
         fetcher = sample_data.metadata_fetcher
         authority = sample_data.metadata_authority
         content_metadata, content_metadata2 = sample_data.content_metadata[:2]
 
         swh_storage.metadata_fetcher_add([fetcher])
         swh_storage.metadata_authority_add([authority])
         swh_storage.object_metadata_add([content_metadata, content_metadata2])
 
         with pytest.raises(StorageArgumentException, match="SWHID"):
             swh_storage.object_metadata_get(
                 MetadataTargetType.CONTENT, origin.url, authority
             )
 
     def test_origin_metadata_add(self, swh_storage, sample_data):
         origin = sample_data.origin
         fetcher = sample_data.metadata_fetcher
         authority = sample_data.metadata_authority
         origin_metadata, origin_metadata2 = sample_data.origin_metadata[:2]
 
         assert swh_storage.origin_add([origin]) == {"origin:add": 1}
 
         swh_storage.metadata_fetcher_add([fetcher])
         swh_storage.metadata_authority_add([authority])
 
         swh_storage.object_metadata_add([origin_metadata, origin_metadata2])
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN, origin.url, authority
         )
         assert result["next_page_token"] is None
         assert list(sorted(result["results"], key=lambda x: x.discovery_date)) == [
             origin_metadata,
             origin_metadata2,
         ]
 
     def test_origin_metadata_add_duplicate(self, swh_storage, sample_data):
         """Duplicates should be silently updated."""
         origin = sample_data.origin
         fetcher = sample_data.metadata_fetcher
         authority = sample_data.metadata_authority
         origin_metadata, origin_metadata2 = sample_data.origin_metadata[:2]
         assert swh_storage.origin_add([origin]) == {"origin:add": 1}
 
         new_origin_metadata2 = attr.evolve(
             origin_metadata2, format="new-format", metadata=b"new-metadata",
         )
 
         swh_storage.metadata_fetcher_add([fetcher])
         swh_storage.metadata_authority_add([authority])
 
         swh_storage.object_metadata_add([origin_metadata, origin_metadata2])
         swh_storage.object_metadata_add([new_origin_metadata2])
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN, origin.url, authority
         )
         assert result["next_page_token"] is None
 
         # which of the two behavior happens is backend-specific.
         expected_results1 = (origin_metadata, new_origin_metadata2)
         expected_results2 = (origin_metadata, origin_metadata2)
 
         assert tuple(sorted(result["results"], key=lambda x: x.discovery_date,)) in (
             expected_results1,  # cassandra
             expected_results2,  # postgresql
         )
 
     def test_origin_metadata_get(self, swh_storage, sample_data):
         origin, origin2 = sample_data.origins[:2]
         fetcher, fetcher2 = sample_data.fetchers[:2]
         authority, authority2 = sample_data.authorities[:2]
         (
             origin1_metadata1,
             origin1_metadata2,
             origin1_metadata3,
         ) = sample_data.origin_metadata[:3]
 
         assert swh_storage.origin_add([origin, origin2]) == {"origin:add": 2}
 
         origin2_metadata = attr.evolve(origin1_metadata2, id=origin2.url)
 
         swh_storage.metadata_authority_add([authority, authority2])
         swh_storage.metadata_fetcher_add([fetcher, fetcher2])
 
         swh_storage.object_metadata_add(
             [origin1_metadata1, origin1_metadata2, origin1_metadata3, origin2_metadata]
         )
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN, origin.url, authority
         )
         assert result["next_page_token"] is None
         assert [origin1_metadata1, origin1_metadata2] == list(
             sorted(result["results"], key=lambda x: x.discovery_date,)
         )
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN, origin.url, authority2
         )
         assert result["next_page_token"] is None
         assert [origin1_metadata3] == list(
             sorted(result["results"], key=lambda x: x.discovery_date,)
         )
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN, origin2.url, authority
         )
         assert result["next_page_token"] is None
         assert [origin2_metadata] == list(result["results"],)
 
     def test_origin_metadata_get_after(self, swh_storage, sample_data):
         origin = sample_data.origin
         fetcher = sample_data.metadata_fetcher
         authority = sample_data.metadata_authority
         origin_metadata, origin_metadata2 = sample_data.origin_metadata[:2]
 
         assert swh_storage.origin_add([origin]) == {"origin:add": 1}
 
         swh_storage.metadata_fetcher_add([fetcher])
         swh_storage.metadata_authority_add([authority])
         swh_storage.object_metadata_add([origin_metadata, origin_metadata2])
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN,
             origin.url,
             authority,
             after=origin_metadata.discovery_date - timedelta(seconds=1),
         )
         assert result["next_page_token"] is None
         assert list(sorted(result["results"], key=lambda x: x.discovery_date,)) == [
             origin_metadata,
             origin_metadata2,
         ]
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN,
             origin.url,
             authority,
             after=origin_metadata.discovery_date,
         )
         assert result["next_page_token"] is None
         assert result["results"] == [origin_metadata2]
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN,
             origin.url,
             authority,
             after=origin_metadata2.discovery_date,
         )
         assert result["next_page_token"] is None
         assert result["results"] == []
 
     def test_origin_metadata_get_paginate(self, swh_storage, sample_data):
         origin = sample_data.origin
         fetcher = sample_data.metadata_fetcher
         authority = sample_data.metadata_authority
         origin_metadata, origin_metadata2 = sample_data.origin_metadata[:2]
         assert swh_storage.origin_add([origin]) == {"origin:add": 1}
 
         swh_storage.metadata_fetcher_add([fetcher])
         swh_storage.metadata_authority_add([authority])
 
         swh_storage.object_metadata_add([origin_metadata, origin_metadata2])
 
         swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN, origin.url, authority
         )
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN, origin.url, authority, limit=1
         )
         assert result["next_page_token"] is not None
         assert result["results"] == [origin_metadata]
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN,
             origin.url,
             authority,
             limit=1,
             page_token=result["next_page_token"],
         )
         assert result["next_page_token"] is None
         assert result["results"] == [origin_metadata2]
 
     def test_origin_metadata_get_paginate_same_date(self, swh_storage, sample_data):
         origin = sample_data.origin
         fetcher1, fetcher2 = sample_data.fetchers[:2]
         authority = sample_data.metadata_authority
         origin_metadata, origin_metadata2 = sample_data.origin_metadata[:2]
         assert swh_storage.origin_add([origin]) == {"origin:add": 1}
 
         swh_storage.metadata_fetcher_add([fetcher1, fetcher2])
         swh_storage.metadata_authority_add([authority])
 
         new_origin_metadata2 = attr.evolve(
             origin_metadata2,
             discovery_date=origin_metadata2.discovery_date,
             fetcher=attr.evolve(fetcher2, metadata=None),
         )
 
         swh_storage.object_metadata_add([origin_metadata, new_origin_metadata2])
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN, origin.url, authority, limit=1
         )
         assert result["next_page_token"] is not None
         assert result["results"] == [origin_metadata]
 
         result = swh_storage.object_metadata_get(
             MetadataTargetType.ORIGIN,
             origin.url,
             authority,
             limit=1,
             page_token=result["next_page_token"],
         )
         assert result["next_page_token"] is None
         assert result["results"] == [new_origin_metadata2]
 
     def test_origin_metadata_add_missing_authority(self, swh_storage, sample_data):
         origin = sample_data.origin
         fetcher = sample_data.metadata_fetcher
         origin_metadata, origin_metadata2 = sample_data.origin_metadata[:2]
         assert swh_storage.origin_add([origin]) == {"origin:add": 1}
 
         swh_storage.metadata_fetcher_add([fetcher])
 
         with pytest.raises(StorageArgumentException, match="authority"):
             swh_storage.object_metadata_add([origin_metadata, origin_metadata2])
 
     def test_origin_metadata_add_missing_fetcher(self, swh_storage, sample_data):
         origin = sample_data.origin
         authority = sample_data.metadata_authority
         origin_metadata, origin_metadata2 = sample_data.origin_metadata[:2]
         assert swh_storage.origin_add([origin]) == {"origin:add": 1}
 
         swh_storage.metadata_authority_add([authority])
 
         with pytest.raises(StorageArgumentException, match="fetcher"):
             swh_storage.object_metadata_add([origin_metadata, origin_metadata2])
 
     def test_origin_metadata_get__invalid_id_type(self, swh_storage, sample_data):
         origin = sample_data.origin
         authority = sample_data.metadata_authority
         fetcher = sample_data.metadata_fetcher
         origin_metadata, origin_metadata2 = sample_data.origin_metadata[:2]
         content_metadata = sample_data.content_metadata[0]
         assert swh_storage.origin_add([origin]) == {"origin:add": 1}
 
         swh_storage.metadata_fetcher_add([fetcher])
         swh_storage.metadata_authority_add([authority])
 
         swh_storage.object_metadata_add([origin_metadata, origin_metadata2])
 
         with pytest.raises(StorageArgumentException, match="SWHID"):
             swh_storage.object_metadata_get(
                 MetadataTargetType.ORIGIN, content_metadata.id, authority,
             )
 
 
 class TestStorageGeneratedData:
     def test_generate_content_get(self, swh_storage, swh_contents):
         contents_with_data = [c.to_dict() 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_with_data]
 
         # retrieve contents
         actual_contents = list(swh_storage.content_get(get_sha1s))
         assert None not in actual_contents
         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
         expected_contents = [c.to_dict() for c in swh_contents if c.status != "absent"]
         get_sha1s = [c["sha1"] for c in expected_contents]
 
         # retrieve contents
         meta_contents = swh_storage.content_get_metadata(get_sha1s)
 
         assert len(list(meta_contents)) == len(get_sha1s)
 
         actual_contents = []
         for contents in meta_contents.values():
             actual_contents.extend(contents)
 
         keys_to_check = {"length", "status", "sha1", "sha1_git", "sha256", "blake2s256"}
 
         assert_contents_ok(
             expected_contents, actual_contents, keys_to_check=keys_to_check
         )
 
     def test_generate_content_get_range(self, swh_storage, swh_contents):
         """content_get_range returns complete range"""
         present_contents = [c.to_dict() for c in swh_contents if c.status != "absent"]
 
         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"]
         expected_contents = [c for c in present_contents if start <= c["sha1"] <= end]
         if expected_contents:
             assert_contents_ok(expected_contents, actual_contents, ["sha1"])
         else:
             assert actual_contents == []
 
     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.to_dict() for c in swh_contents if c.status != "absent"]
 
         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:
             assert_contents_ok(expected_contents, actual_contents, ["sha1"])
         else:
             assert actual_contents == []
 
     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 pytest.raises(StorageArgumentException) as e:
             swh_storage.content_get_range(start=None, end=None, limit=None)
 
         assert e.value.args == ("limit should not be None",)
 
     def test_generate_content_get_range_no_limit(self, swh_storage, swh_contents):
         """content_get_range returns contents within range provided"""
         # input the list of sha1s we want from storage
         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 = swh_storage.content_get_range(start, end)
 
         actual_contents = actual_result["contents"]
         assert actual_result["next"] is None
         assert len(actual_contents) == len(get_sha1s)
 
         expected_contents = [c.to_dict() for c in swh_contents if c.status != "absent"]
         assert_contents_ok(expected_contents, actual_contents, ["sha1"])
 
     def test_generate_content_get_range_limit(self, swh_storage, swh_contents):
         """content_get_range paginates results if limit exceeded"""
         contents_map = {c.sha1: c.to_dict() for c in swh_contents}
 
         # input the list of sha1s we want from storage
         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 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"]
         assert actual_result["next"] == get_sha1s[-1]
         assert len(actual_contents) == limited_results
 
         expected_contents = [contents_map[sha1] for sha1 in get_sha1s[:-1]]
         assert_contents_ok(expected_contents, actual_contents, ["sha1"])
 
         # retrieve next part
         actual_results2 = swh_storage.content_get_range(start=end, end=end)
         assert actual_results2["next"] is None
         actual_contents2 = actual_results2["contents"]
         assert len(actual_contents2) == 1
 
         assert_contents_ok([contents_map[get_sha1s[-1]]], actual_contents2, ["sha1"])
 
     def test_origin_get_range_from_zero(self, swh_storage, swh_origins):
         actual_origins = list(
             swh_storage.origin_get_range(origin_from=0, origin_count=0)
         )
         assert len(actual_origins) == 0
 
         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
         assert actual_origins[0]["url"] == swh_origins[0].url
 
     @pytest.mark.parametrize(
         "origin_from,origin_count",
         [(1, 1), (1, 10), (1, 20), (1, 101), (11, 0), (11, 10), (91, 11)],
     )
     def test_origin_get_range(
         self, swh_storage, swh_origins, origin_from, origin_count
     ):
         actual_origins = list(
             swh_storage.origin_get_range(
                 origin_from=origin_from, origin_count=origin_count
             )
         )
 
         origins_with_id = list(enumerate(swh_origins, start=1))
         expected_origins = [
             {"url": origin.url, "id": origin_id,}
             for (origin_id, origin) in origins_with_id[
                 origin_from - 1 : origin_from + origin_count - 1
             ]
         ]
 
         assert actual_origins == expected_origins
 
     @pytest.mark.parametrize("limit", [1, 7, 10, 100, 1000])
     def test_origin_list(self, swh_storage, swh_origins, limit):
         returned_origins = []
 
         page_token = None
         i = 0
         while True:
             result = swh_storage.origin_list(page_token=page_token, limit=limit)
             assert len(result["origins"]) <= limit
 
             returned_origins.extend(origin["url"] for origin in result["origins"])
 
             i += 1
             page_token = result.get("next_page_token")
 
             if page_token is None:
                 assert i * limit >= len(swh_origins)
                 break
             else:
                 assert len(result["origins"]) == limit
 
         expected_origins = [origin.url for origin in swh_origins]
         assert sorted(returned_origins) == sorted(expected_origins)
 
     def test_origin_count(self, swh_storage, sample_data):
         swh_storage.origin_add(sample_data.origins)
 
         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
 
     def test_origin_count_with_visit_no_visits(self, swh_storage, sample_data):
         swh_storage.origin_add(sample_data.origins)
 
         # none of them have visits, so with_visit=True => 0
         assert swh_storage.origin_count("github", with_visit=True) == 0
         assert swh_storage.origin_count("gitlab", with_visit=True) == 0
         assert swh_storage.origin_count(".*user.*", regexp=True, with_visit=True) == 0
         assert swh_storage.origin_count(".*user.*", regexp=False, with_visit=True) == 0
         assert swh_storage.origin_count(".*user1.*", regexp=True, with_visit=True) == 0
         assert swh_storage.origin_count(".*user1.*", regexp=False, with_visit=True) == 0
 
     def test_origin_count_with_visit_with_visits_no_snapshot(
         self, swh_storage, sample_data
     ):
         swh_storage.origin_add(sample_data.origins)
 
         origin_url = "https://github.com/user1/repo1"
         visit = OriginVisit(origin=origin_url, date=now(), type="git",)
         swh_storage.origin_visit_add([visit])
 
         assert swh_storage.origin_count("github", with_visit=False) == 3
         # it has a visit, but no snapshot, so with_visit=True => 0
         assert swh_storage.origin_count("github", with_visit=True) == 0
 
         assert swh_storage.origin_count("gitlab", with_visit=False) == 2
         # these gitlab origins have no visit
         assert swh_storage.origin_count("gitlab", with_visit=True) == 0
 
         assert (
             swh_storage.origin_count("github.*user1", regexp=True, with_visit=False)
             == 1
         )
         assert (
             swh_storage.origin_count("github.*user1", regexp=True, with_visit=True) == 0
         )
         assert swh_storage.origin_count("github", regexp=True, with_visit=True) == 0
 
     def test_origin_count_with_visit_with_visits_and_snapshot(
         self, swh_storage, sample_data
     ):
         snapshot = sample_data.snapshot
         swh_storage.origin_add(sample_data.origins)
 
         swh_storage.snapshot_add([snapshot])
         origin_url = "https://github.com/user1/repo1"
         visit = OriginVisit(origin=origin_url, date=now(), type="git",)
         visit = swh_storage.origin_visit_add([visit])[0]
         swh_storage.origin_visit_status_add(
             [
                 OriginVisitStatus(
                     origin=origin_url,
                     visit=visit.visit,
                     date=now(),
                     status="ongoing",
                     snapshot=snapshot.id,
                 )
             ]
         )
 
         assert swh_storage.origin_count("github", with_visit=False) == 3
         # github/user1 has a visit and a snapshot, so with_visit=True => 1
         assert swh_storage.origin_count("github", with_visit=True) == 1
 
         assert (
             swh_storage.origin_count("github.*user1", regexp=True, with_visit=False)
             == 1
         )
         assert (
             swh_storage.origin_count("github.*user1", regexp=True, with_visit=True) == 1
         )
         assert swh_storage.origin_count("github", regexp=True, with_visit=True) == 1
 
     @settings(suppress_health_check=[HealthCheck.too_slow])
     @given(strategies.lists(objects(split_content=True), max_size=2))
     def test_add_arbitrary(self, swh_storage, objects):
         for (obj_type, obj) in objects:
             if obj.object_type == "origin_visit":
                 swh_storage.origin_add([Origin(url=obj.origin)])
                 visit = OriginVisit(origin=obj.origin, date=obj.date, type=obj.type,)
                 swh_storage.origin_visit_add([visit])
             else:
                 method = getattr(swh_storage, obj_type + "_add")
                 try:
                     method([obj])
                 except HashCollision:
                     pass
 
 
 @pytest.mark.db
 class TestLocalStorage:
     """Test the local storage"""
 
     # This test is only relevant on the local storage, with an actual
     # objstorage raising an exception
     def test_content_add_objstorage_exception(self, swh_storage, sample_data):
         content = sample_data.content
 
         swh_storage.objstorage.content_add = Mock(
             side_effect=Exception("mocked broken objstorage")
         )
 
         with pytest.raises(Exception, match="mocked broken"):
             swh_storage.content_add([content])
 
         missing = list(swh_storage.content_missing([content.hashes()]))
         assert missing == [content.sha1]
 
 
 @pytest.mark.db
 class TestStorageRaceConditions:
     @pytest.mark.xfail
     def test_content_add_race(self, swh_storage, sample_data):
         content = sample_data.content
 
         results = queue.Queue()
 
         def thread():
             try:
                 with db_transaction(swh_storage) as (db, cur):
                     ret = swh_storage.content_add([content], 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
 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_with_new_cols(self, swh_storage, sample_data):
         content, content2 = sample_data.contents[:2]
 
         swh_storage.journal_writer.journal = None  # TODO, not supported
 
         with db_transaction(swh_storage) as (_, cur):
             cur.execute(
                 """alter table content
                            add column test text default null,
                            add column test2 text default null"""
             )
 
         swh_storage.content_add([content])
 
         cont = content.to_dict()
         cont["test"] = "value-1"
         cont["test2"] = "value-2"
 
         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()
 
         assert datum == (
             cont["sha1"],
             cont["sha1_git"],
             cont["sha256"],
             cont["length"],
             "visible",
             cont["test"],
             cont["test2"],
         )
 
         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, sample_data):
         content = sample_data.content
 
         actual_result = swh_storage.content_add([content])
 
         assert actual_result == {
             "content:add": 1,
             "content:add:bytes": content.length,
         }
 
         if hasattr(swh_storage, "objstorage"):
             assert content.sha1 in swh_storage.objstorage.objstorage
 
         with db_transaction(swh_storage) as (_, cur):
             cur.execute(
                 "SELECT sha1, sha1_git, sha256, length, status"
                 " FROM content WHERE sha1 = %s",
                 (content.sha1,),
             )
             datum = cur.fetchone()
 
         assert datum == (
             content.sha1,
             content.sha1_git,
             content.sha256,
             content.length,
             "visible",
         )
 
         contents = [
             obj
             for (obj_type, obj) in swh_storage.journal_writer.journal.objects
             if obj_type == "content"
         ]
         assert len(contents) == 1
         assert contents[0] == attr.evolve(content, data=None)
 
     def test_content_add_metadata_db(self, swh_storage, sample_data):
         content = attr.evolve(sample_data.content, data=None, ctime=now())
 
         actual_result = swh_storage.content_add_metadata([content])
 
         assert actual_result == {
             "content:add": 1,
         }
 
         if hasattr(swh_storage, "objstorage"):
             assert content.sha1 not in swh_storage.objstorage.objstorage
         with db_transaction(swh_storage) as (_, cur):
             cur.execute(
                 "SELECT sha1, sha1_git, sha256, length, status"
                 " FROM content WHERE sha1 = %s",
                 (content.sha1,),
             )
             datum = cur.fetchone()
         assert datum == (
             content.sha1,
             content.sha1_git,
             content.sha256,
             content.length,
             "visible",
         )
 
         contents = [
             obj
             for (obj_type, obj) in swh_storage.journal_writer.journal.objects
             if obj_type == "content"
         ]
         assert len(contents) == 1
         assert contents[0] == content
 
     def test_skipped_content_add_db(self, swh_storage, sample_data):
         content, cont2 = sample_data.skipped_contents[:2]
         content2 = attr.evolve(cont2, blake2s256=None)
 
         actual_result = swh_storage.skipped_content_add([content, content, content2])
 
         assert 2 <= actual_result.pop("skipped_content:add") <= 3
         assert actual_result == {}
 
         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] == (
             content.sha1,
             content.sha1_git,
             content.sha256,
             content.blake2s256,
             content.length,
             "absent",
             "Content too long",
         )
 
         assert dbdata[1] == (
             content2.sha1,
             content2.sha1_git,
             content2.sha256,
             content2.blake2s256,
             content2.length,
             "absent",
             "Content too long",
         )
 
     def test_clear_buffers(self, swh_storage):
         """Calling clear buffers on real storage does nothing
 
         """
         assert swh_storage.clear_buffers() is None
 
     def test_flush(self, swh_storage):
         """Calling clear buffers on real storage does nothing
 
         """
         assert swh_storage.flush() == {}