diff --git a/swh/loader/package/archive/tests/test_archive.py b/swh/loader/package/archive/tests/test_archive.py
index de3a4d0..8e207c4 100644
--- a/swh/loader/package/archive/tests/test_archive.py
+++ b/swh/loader/package/archive/tests/test_archive.py
@@ -1,345 +1,345 @@
-# Copyright (C) 2019 The Software Heritage developers
+# Copyright (C) 2019-2020 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
 
 from swh.model.hashutil import hash_to_bytes
 
 from swh.loader.package.archive.loader import ArchiveLoader
 from swh.loader.package.tests.common import (
     check_snapshot, check_metadata_paths, get_stats
 )
 
 
 URL = 'https://ftp.gnu.org/gnu/8sync/'
 GNU_ARTIFACTS = [
     {
         'time': 944729610,
         'url': 'https://ftp.gnu.org/gnu/8sync/8sync-0.1.0.tar.gz',
         'length': 221837,
         'filename': '8sync-0.1.0.tar.gz',
         'version': '0.1.0',
     }
 ]
 
 _expected_new_contents_first_visit = [
     'e9258d81faf5881a2f96a77ba609396f82cb97ad',
     '1170cf105b04b7e2822a0e09d2acf71da7b9a130',
     'fbd27c3f41f2668624ffc80b7ba5db9b92ff27ac',
     '0057bec9b5422aff9256af240b177ac0e3ac2608',
     '2b8d0d0b43a1078fc708930c8ddc2956a86c566e',
     '27de3b3bc6545d2a797aeeb4657c0e215a0c2e55',
     '2e6db43f5cd764e677f416ff0d0c78c7a82ef19b',
     'ae9be03bd2a06ed8f4f118d3fe76330bb1d77f62',
     'edeb33282b2bffa0e608e9d2fd960fd08093c0ea',
     'd64e64d4c73679323f8d4cde2643331ba6c20af9',
     '7a756602914be889c0a2d3952c710144b3e64cb0',
     '84fb589b554fcb7f32b806951dcf19518d67b08f',
     '8624bcdae55baeef00cd11d5dfcfa60f68710a02',
     'e08441aeab02704cfbd435d6445f7c072f8f524e',
     'f67935bc3a83a67259cda4b2d43373bd56703844',
     '809788434b433eb2e3cfabd5d591c9a659d5e3d8',
     '7d7c6c8c5ebaeff879f61f37083a3854184f6c41',
     'b99fec102eb24bffd53ab61fc30d59e810f116a2',
     '7d149b28eaa228b3871c91f0d5a95a2fa7cb0c68',
     'f0c97052e567948adf03e641301e9983c478ccff',
     '7fb724242e2b62b85ca64190c31dcae5303e19b3',
     '4f9709e64a9134fe8aefb36fd827b84d8b617ab5',
     '7350628ccf194c2c3afba4ac588c33e3f3ac778d',
     '0bb892d9391aa706dc2c3b1906567df43cbe06a2',
     '49d4c0ce1a16601f1e265d446b6c5ea6b512f27c',
     '6b5cc594ac466351450f7f64a0b79fdaf4435ad3',
     '3046e5d1f70297e2a507b98224b6222c9688d610',
     '1572607d456d7f633bc6065a2b3048496d679a31',
 ]
 
 _expected_new_directories_first_visit = [
     'daabc65ec75d487b1335ffc101c0ac11c803f8fc',
     '263be23b4a8101d3ad0d9831319a3e0f2b065f36',
     '7f6e63ba6eb3e2236f65892cd822041f1a01dd5c',
     '4db0a3ecbc976083e2dac01a62f93729698429a3',
     'dfef1c80e1098dd5deda664bb44a9ab1f738af13',
     'eca971d346ea54d95a6e19d5051f900237fafdaa',
     '3aebc29ed1fccc4a6f2f2010fb8e57882406b528',
 ]
 
 _expected_new_revisions_first_visit = {
     '44183488c0774ce3c957fa19ba695cf18a4a42b3':
     '3aebc29ed1fccc4a6f2f2010fb8e57882406b528'
 }
 
 _expected_branches_first_visit = {
     'HEAD': {
         'target_type': 'alias',
         'target': 'releases/0.1.0',
     },
     'releases/0.1.0': {
         'target_type': 'revision',
         'target': '44183488c0774ce3c957fa19ba695cf18a4a42b3',
     },
 }
 
 # hash is different then before as we changed the snapshot
 # gnu used to use `release/` (singular) instead of plural
 _expected_new_snapshot_first_visit_id = 'c419397fd912039825ebdbea378bc6283f006bf5'  # noqa
 
 
 def visit_with_no_artifact_found(swh_config, requests_mock_datadir):
     url = URL
     unknown_artifact_url = 'https://ftp.g.o/unknown/8sync-0.1.0.tar.gz'
     loader = ArchiveLoader(url, artifacts=[
         {
             'time': 944729610,
             'url': unknown_artifact_url,  # unknown artifact
             'length': 221837,
             'filename': '8sync-0.1.0.tar.gz',
             'version': '0.1.0',
         }
     ])
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'uneventful'
     assert actual_load_status['snapshot_id'] is not None
     stats = get_stats(loader.storage)
 
     assert {
         'content': 0,
         'directory': 0,
         'origin': 1,
         'origin_visit': 1,
         'person': 0,
         'release': 0,
         'revision': 0,
         'skipped_content': 0,
         'snapshot': 1,
     } == stats
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'partial'
     assert origin_visit['type'] == 'tar'
 
 
 def test_check_revision_metadata_structure(swh_config, requests_mock_datadir):
     loader = ArchiveLoader(url=URL, artifacts=GNU_ARTIFACTS)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
     assert actual_load_status['snapshot_id'] is not None
 
     expected_revision_id = hash_to_bytes(
         '44183488c0774ce3c957fa19ba695cf18a4a42b3')
     revision = list(loader.storage.revision_get([expected_revision_id]))[0]
 
     assert revision is not None
 
     check_metadata_paths(revision['metadata'], paths=[
         ('intrinsic', dict),
         ('extrinsic.provider', str),
         ('extrinsic.when', str),
         ('extrinsic.raw', dict),
         ('original_artifact', list),
     ])
 
     for original_artifact in revision['metadata']['original_artifact']:
         check_metadata_paths(original_artifact, paths=[
             ('filename', str),
             ('length', int),
             ('checksums', dict),
         ])
 
 
 def test_visit_with_release_artifact_no_prior_visit(
         swh_config, requests_mock_datadir):
     """With no prior visit, load a gnu project ends up with 1 snapshot
 
     """
     loader = ArchiveLoader(url=URL, artifacts=GNU_ARTIFACTS)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
     assert actual_load_status['snapshot_id'] == _expected_new_snapshot_first_visit_id  # noqa
 
     stats = get_stats(loader.storage)
     assert {
         'content': len(_expected_new_contents_first_visit),
         'directory': len(_expected_new_directories_first_visit),
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': len(_expected_new_revisions_first_visit),
         'skipped_content': 0,
         'snapshot': 1
     } == stats
 
     expected_contents = map(hash_to_bytes, _expected_new_contents_first_visit)
     assert list(loader.storage.content_missing_per_sha1(expected_contents)) \
         == []
 
     expected_dirs = map(hash_to_bytes, _expected_new_directories_first_visit)
     assert list(loader.storage.directory_missing(expected_dirs)) == []
 
     expected_revs = map(hash_to_bytes, _expected_new_revisions_first_visit)
     assert list(loader.storage.revision_missing(expected_revs)) == []
 
     expected_snapshot = {
         'id': _expected_new_snapshot_first_visit_id,
         'branches': _expected_branches_first_visit,
     }
 
     check_snapshot(expected_snapshot, loader.storage)
 
 
 def test_2_visits_without_change(swh_config, requests_mock_datadir):
     """With no prior visit, load a gnu project ends up with 1 snapshot
 
     """
     url = URL
     loader = ArchiveLoader(url, artifacts=GNU_ARTIFACTS)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
     assert actual_load_status['snapshot_id'] is not None
-    origin_visit = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'tar'
 
     actual_load_status2 = loader.load()
     assert actual_load_status2['status'] == 'uneventful'
     assert actual_load_status2['snapshot_id'] is not None
 
     assert actual_load_status['snapshot_id'] == actual_load_status2[
         'snapshot_id']
 
-    origin_visit2 = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit2 = loader.storage.origin_visit_get_latest(url)
     assert origin_visit2['status'] == 'full'
     assert origin_visit2['type'] == 'tar'
 
     urls = [
         m.url for m in requests_mock_datadir.request_history
         if m.url.startswith('https://ftp.gnu.org')
     ]
     assert len(urls) == 1
 
 
 def test_2_visits_with_new_artifact(swh_config, requests_mock_datadir):
     """With no prior visit, load a gnu project ends up with 1 snapshot
 
     """
     url = URL
     artifact1 = GNU_ARTIFACTS[0]
     loader = ArchiveLoader(url, [artifact1])
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
     assert actual_load_status['snapshot_id'] is not None
 
-    origin_visit = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'tar'
 
     stats = get_stats(loader.storage)
     assert {
         'content': len(_expected_new_contents_first_visit),
         'directory': len(_expected_new_directories_first_visit),
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': len(_expected_new_revisions_first_visit),
         'skipped_content': 0,
         'snapshot': 1
     } == stats
 
     urls = [
         m.url for m in requests_mock_datadir.request_history
         if m.url.startswith('https://ftp.gnu.org')
     ]
     assert len(urls) == 1
 
     artifact2 = {
         'time': 1480991830,
         'url': 'https://ftp.gnu.org/gnu/8sync/8sync-0.2.0.tar.gz',
         'length': 238466,
         'filename': '8sync-0.2.0.tar.gz',
         'version': '0.2.0',
     }
 
     loader2 = ArchiveLoader(url, [artifact1, artifact2])
     # implementation detail: share the storage in between visits
     loader2.storage = loader.storage
     stats2 = get_stats(loader2.storage)
     assert stats == stats2  # ensure we share the storage
 
     actual_load_status2 = loader2.load()
     assert actual_load_status2['status'] == 'eventful'
     assert actual_load_status2['snapshot_id'] is not None
 
     stats2 = get_stats(loader.storage)
     assert {
         'content': len(_expected_new_contents_first_visit) + 14,
         'directory': len(_expected_new_directories_first_visit) + 8,
         'origin': 1,
         'origin_visit': 1 + 1,
         'person': 1,
         'release': 0,
         'revision': len(_expected_new_revisions_first_visit) + 1,
         'skipped_content': 0,
         'snapshot': 1 + 1,
     } == stats2
 
-    origin_visit2 = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit2 = loader.storage.origin_visit_get_latest(url)
     assert origin_visit2['status'] == 'full'
     assert origin_visit2['type'] == 'tar'
 
     urls = [
         m.url for m in requests_mock_datadir.request_history
         if m.url.startswith('https://ftp.gnu.org')
     ]
     # 1 artifact (2nd time no modification) + 1 new artifact
     assert len(urls) == 2
 
 
 def test_2_visits_without_change_not_gnu(swh_config, requests_mock_datadir):
     """Load a project archive (not gnu) ends up with 1 snapshot
 
     """
     url = 'https://something.else.org/8sync/'
     artifacts = [  # this is not a gnu artifact
         {
             'time': '1999-12-09T09:53:30+00:00',  # it's also not a timestamp
             'sha256': 'd5d1051e59b2be6f065a9fc6aedd3a391e44d0274b78b9bb4e2b57a09134dbe4',  # noqa
             # keep a gnu artifact reference to avoid adding other test files
             'url': 'https://ftp.gnu.org/gnu/8sync/8sync-0.2.0.tar.gz',
             'length': 238466,
             'filename': '8sync-0.2.0.tar.gz',
             'version': '0.2.0',
         }
     ]
 
     # Here the loader defines the id_keys to use for existence in the snapshot
     # It's not the default archive loader which
     loader = ArchiveLoader(
         url, artifacts=artifacts, identity_artifact_keys=[
             'sha256', 'length', 'url'])
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
     assert actual_load_status['snapshot_id'] is not None
-    origin_visit = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'tar'
 
     actual_load_status2 = loader.load()
     assert actual_load_status2['status'] == 'uneventful'
     assert actual_load_status2['snapshot_id'] == actual_load_status[
         'snapshot_id']
-    origin_visit2 = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit2 = loader.storage.origin_visit_get_latest(url)
     assert origin_visit2['status'] == 'full'
     assert origin_visit2['type'] == 'tar'
 
     urls = [
         m.url for m in requests_mock_datadir.request_history
         if m.url.startswith('https://ftp.gnu.org')
     ]
     assert len(urls) == 1
diff --git a/swh/loader/package/cran/tests/test_cran.py b/swh/loader/package/cran/tests/test_cran.py
index eae2c4a..730a3a3 100644
--- a/swh/loader/package/cran/tests/test_cran.py
+++ b/swh/loader/package/cran/tests/test_cran.py
@@ -1,330 +1,330 @@
 # Copyright (C) 2019-2020 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 os
 import pytest
 
 from datetime import datetime, timezone
 from dateutil.tz import tzlocal
 
 from os import path
 
 from swh.loader.package.cran.loader import (
     extract_intrinsic_metadata, CRANLoader, parse_date,
     parse_debian_control
 )
 from swh.core.tarball import uncompress
 from swh.model.model import TimestampWithTimezone
 
 from swh.loader.package.tests.common import (
     check_snapshot, get_stats
 )
 
 
 def test_cran_parse_date():
     data = [
         # parsable, some have debatable results though
         ('2001-June-08',
          datetime(2001, 6, 8, 0, 0, tzinfo=timezone.utc)),
         ('Tue Dec 27 15:06:08 PST 2011',
          datetime(2011, 12, 27, 15, 6, 8, tzinfo=timezone.utc)),
         ('8-14-2013',
          datetime(2013, 8, 14, 0, 0, tzinfo=timezone.utc)),
         ('2011-01',
          datetime(2011, 1, 1, 0, 0, tzinfo=timezone.utc)),
         ('201109',
          datetime(2009, 11, 20, 0, 0, tzinfo=timezone.utc)),
         ('04-12-2014',
          datetime(2014, 4, 12, 0, 0, tzinfo=timezone.utc)),
         ('2018-08-24, 10:40:10',
          datetime(2018, 8, 24, 10, 40, 10, tzinfo=timezone.utc)),
         ('2013-October-16',
          datetime(2013, 10, 16, 0, 0, tzinfo=timezone.utc)),
         ('Aug 23, 2013',
          datetime(2013, 8, 23, 0, 0, tzinfo=timezone.utc)),
         ('27-11-2014',
          datetime(2014, 11, 27, 0, 0, tzinfo=timezone.utc)),
         ('2019-09-26,',
          datetime(2019, 9, 26, 0, 0, tzinfo=timezone.utc)),
         ('9/25/2014',
          datetime(2014, 9, 25, 0, 0, tzinfo=timezone.utc)),
         ('Fri Jun 27 17:23:53 2014',
          datetime(2014, 6, 27, 17, 23, 53, tzinfo=timezone.utc)),
         ('28-04-2014',
          datetime(2014, 4, 28, 0, 0, tzinfo=timezone.utc)),
         ('04-14-2014',
          datetime(2014, 4, 14, 0, 0, tzinfo=timezone.utc)),
         ('2019-05-08 14:17:31 UTC',
          datetime(2019, 5, 8, 14, 17, 31, tzinfo=timezone.utc)),
         ('Wed May 21 13:50:39 CEST 2014',
          datetime(2014, 5, 21, 13, 50, 39, tzinfo=tzlocal())),
         ('2018-04-10 00:01:04 KST',
          datetime(2018, 4, 10, 0, 1, 4, tzinfo=timezone.utc)),
         ('2019-08-25 10:45',
          datetime(2019, 8, 25, 10, 45, tzinfo=timezone.utc)),
         ('March 9, 2015',
          datetime(2015, 3, 9, 0, 0, tzinfo=timezone.utc)),
         ('Aug. 18, 2012',
          datetime(2012, 8, 18, 0, 0, tzinfo=timezone.utc)),
         ('2014-Dec-17',
          datetime(2014, 12, 17, 0, 0, tzinfo=timezone.utc)),
         ('March 01, 2013',
          datetime(2013, 3, 1, 0, 0, tzinfo=timezone.utc)),
         ('2017-04-08.',
          datetime(2017, 4, 8, 0, 0, tzinfo=timezone.utc)),
         ('2014-Apr-22',
          datetime(2014, 4, 22, 0, 0, tzinfo=timezone.utc)),
         ('Mon Jan 12 19:54:04 2015',
          datetime(2015, 1, 12, 19, 54, 4, tzinfo=timezone.utc)),
         ('May 22, 2014',
          datetime(2014, 5, 22, 0, 0, tzinfo=timezone.utc)),
         ('2014-08-12 09:55:10 EDT',
          datetime(2014, 8, 12, 9, 55, 10, tzinfo=timezone.utc)),
         # unparsable
         ('Fabruary 21, 2012', None),
         ('2019-05-28"', None),
         ('2017-03-01 today', None),
         ('2016-11-0110.1093/icesjms/fsw182', None),
         ('2019-07-010', None),
         ('2015-02.23', None),
         ('20013-12-30', None),
         ('2016-08-017', None),
         ('2019-02-07l', None),
         ('2018-05-010', None),
         ('2019-09-27 KST', None),
         ('$Date$', None),
         ('2019-09-27 KST', None),
         ('2019-06-22 $Date$', None),
         ('$Date: 2013-01-18 12:49:03 -0600 (Fri, 18 Jan 2013) $', None),
         ('2015-7-013', None),
         ('2018-05-023', None),
         ("Check NEWS file for changes: news(package='simSummary')", None)
     ]
     for date, expected_date in data:
         actual_tstz = parse_date(date)
         if expected_date is None:
             assert actual_tstz is None, date
         else:
             expected_tstz = TimestampWithTimezone.from_datetime(expected_date)
             assert actual_tstz == expected_tstz, date
 
 
 @pytest.mark.fs
 def test_extract_intrinsic_metadata(tmp_path, datadir):
     """Parsing existing archive's PKG-INFO should yield results"""
     uncompressed_archive_path = str(tmp_path)
     # sample url
     # https://cran.r-project.org/src_contrib_1.4.0_Recommended_KernSmooth_2.22-6.tar.gz  # noqa
     archive_path = path.join(
         datadir, 'https_cran.r-project.org',
         'src_contrib_1.4.0_Recommended_KernSmooth_2.22-6.tar.gz')
     uncompress(archive_path, dest=uncompressed_archive_path)
 
     actual_metadata = extract_intrinsic_metadata(uncompressed_archive_path)
 
     expected_metadata = {
         'Package': 'KernSmooth',
         'Priority': 'recommended',
         'Version': '2.22-6',
         'Date': '2001-June-08',
         'Title': 'Functions for kernel smoothing for Wand & Jones (1995)',
         'Author': 'S original by Matt Wand.\n\tR port by  Brian Ripley <ripley@stats.ox.ac.uk>.',  # noqa
         'Maintainer': 'Brian Ripley <ripley@stats.ox.ac.uk>',
         'Description': 'functions for kernel smoothing (and density estimation)\n  corresponding to the book: \n  Wand, M.P. and Jones, M.C. (1995) "Kernel Smoothing".',  # noqa
         'License': 'Unlimited use and distribution (see LICENCE).',
         'URL': 'http://www.biostat.harvard.edu/~mwand'
     }
 
     assert actual_metadata == expected_metadata
 
 
 @pytest.mark.fs
 def test_extract_intrinsic_metadata_failures(tmp_path):
     """Parsing inexistent path/archive/PKG-INFO yield None"""
     # inexistent first level path
     assert extract_intrinsic_metadata('/something-inexistent') == {}
     # inexistent second level path (as expected by pypi archives)
     assert extract_intrinsic_metadata(tmp_path) == {}
     # inexistent PKG-INFO within second level path
     existing_path_no_pkginfo = str(tmp_path / 'something')
     os.mkdir(existing_path_no_pkginfo)
     assert extract_intrinsic_metadata(tmp_path) == {}
 
 
 def test_cran_one_visit(swh_config, requests_mock_datadir):
     version = '2.22-6'
     base_url = 'https://cran.r-project.org'
     origin_url = f'{base_url}/Packages/Recommended_KernSmooth/index.html'
     artifact_url = f'{base_url}/src_contrib_1.4.0_Recommended_KernSmooth_{version}.tar.gz'  # noqa
     loader = CRANLoader(origin_url, artifacts=[{
         'url': artifact_url,
         'version': version,
     }])
 
     actual_load_status = loader.load()
 
     expected_snapshot_id = '920adcccc78aaeedd3cfa4459dd900d8c3431a21'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': {
             'HEAD': {'target': f'releases/{version}', 'target_type': 'alias'},
             f'releases/{version}': {
                 'target': '42bdb16facd5140424359c8ce89a28ecfa1ce603',
                 'target_type': 'revision'
             }
         }
     }
     check_snapshot(expected_snapshot, loader.storage)
 
-    origin_visit = next(loader.storage.origin_visit_get(origin_url))
+    origin_visit = loader.storage.origin_visit_get_latest(origin_url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'cran'
 
     visit_stats = get_stats(loader.storage)
     assert {
         'content': 33,
         'directory': 7,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 1,
         'skipped_content': 0,
         'snapshot': 1
     } == visit_stats
 
     urls = [
         m.url for m in requests_mock_datadir.request_history
         if m.url.startswith(base_url)
     ]
     # visited each artifact once across 2 visits
     assert len(urls) == 1
 
 
 def test_cran_2_visits_same_origin(
         swh_config, requests_mock_datadir):
     """Multiple visits on the same origin, only 1 archive fetch"""
     version = '2.22-6'
     base_url = 'https://cran.r-project.org'
     origin_url = f'{base_url}/Packages/Recommended_KernSmooth/index.html'
     artifact_url = f'{base_url}/src_contrib_1.4.0_Recommended_KernSmooth_{version}.tar.gz'  # noqa
     loader = CRANLoader(origin_url, artifacts=[{
         'url': artifact_url,
         'version': version
     }])
 
     # first visit
     actual_load_status = loader.load()
 
     expected_snapshot_id = '920adcccc78aaeedd3cfa4459dd900d8c3431a21'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': {
             'HEAD': {'target': f'releases/{version}', 'target_type': 'alias'},
             f'releases/{version}': {
                 'target': '42bdb16facd5140424359c8ce89a28ecfa1ce603',
                 'target_type': 'revision'
             }
         }
     }
     check_snapshot(expected_snapshot, loader.storage)
 
-    origin_visit = next(loader.storage.origin_visit_get(origin_url))
+    origin_visit = loader.storage.origin_visit_get_latest(origin_url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'cran'
 
     visit_stats = get_stats(loader.storage)
     assert {
         'content': 33,
         'directory': 7,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 1,
         'skipped_content': 0,
         'snapshot': 1
     } == visit_stats
 
     # second visit
     actual_load_status2 = loader.load()
 
     assert actual_load_status2 == {
         'status': 'uneventful',
         'snapshot_id': expected_snapshot_id
     }
 
-    origin_visit2 = next(loader.storage.origin_visit_get(origin_url))
+    origin_visit2 = loader.storage.origin_visit_get_latest(origin_url)
     assert origin_visit2['status'] == 'full'
     assert origin_visit2['type'] == 'cran'
 
     visit_stats2 = get_stats(loader.storage)
     visit_stats['origin_visit'] += 1
     assert visit_stats2 == visit_stats, 'same stats as 1st visit, +1 visit'
 
     urls = [
         m.url for m in requests_mock_datadir.request_history
         if m.url.startswith(base_url)
     ]
     assert len(urls) == 1, 'visited one time artifact url (across 2 visits)'
 
 
 def test_parse_debian_control(datadir):
     description_file = os.path.join(datadir, 'description', 'acepack')
 
     actual_metadata = parse_debian_control(description_file)
 
     assert actual_metadata == {
         'Package': 'acepack',
         'Maintainer': 'Shawn Garbett',
         'Version': '1.4.1',
         'Author': 'Phil Spector, Jerome Friedman, Robert Tibshirani...',
         'Description': 'Two nonparametric methods for multiple regression...',
         'Title': 'ACE & AVAS 4 Selecting Multiple Regression Transformations',
         'License': 'MIT + file LICENSE',
         'Suggests': 'testthat',
         'Packaged': '2016-10-28 15:38:59 UTC; garbetsp',
         'Repository': 'CRAN',
         'Date/Publication': '2016-10-29 00:11:52',
         'NeedsCompilation': 'yes'
     }
 
 
 def test_parse_debian_control_unicode_issue(datadir):
     # iso-8859-1 caused failure, now fixed
     description_file = os.path.join(
         datadir, 'description', 'KnownBR'
     )
 
     actual_metadata = parse_debian_control(description_file)
 
     assert actual_metadata == {
         'Package': 'KnowBR',
         'Version': '2.0',
         'Title': '''Discriminating Well Surveyed Spatial Units from Exhaustive
         Biodiversity Databases''',
         'Author': 'Cástor Guisande González and Jorge M. Lobo',
         'Maintainer': 'Cástor Guisande González <castor@email.es>',
         'Description':
         'It uses species accumulation curves and diverse estimators...',
         'License': 'GPL (>= 2)',
         'Encoding': 'latin1',
         'Depends': 'R (>= 3.0), fossil, mgcv, plotrix, sp, vegan',
         'Suggests': 'raster, rgbif',
         'NeedsCompilation': 'no',
         'Packaged': '2019-01-30 13:27:29 UTC; castor',
         'Repository': 'CRAN',
         'Date/Publication': '2019-01-31 20:53:50 UTC'
     }
diff --git a/swh/loader/package/debian/tests/test_debian.py b/swh/loader/package/debian/tests/test_debian.py
index f4e3307..f48544b 100644
--- a/swh/loader/package/debian/tests/test_debian.py
+++ b/swh/loader/package/debian/tests/test_debian.py
@@ -1,464 +1,464 @@
-# Copyright (C) 2019  The Software Heritage developers
+# Copyright (C) 2019-2020  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 copy
 import logging
 import pytest
 import random
 
 from os import path
 
 from swh.loader.package.debian.loader import (
     DebianLoader, download_package, dsc_information, uid_to_person,
     prepare_person, get_package_metadata, extract_package
 )
 from swh.loader.package.tests.common import check_snapshot, get_stats
 from swh.loader.package.debian.loader import resolve_revision_from
 
 from swh.model.model import Person
 
 
 logger = logging.getLogger(__name__)
 
 
 PACKAGE_FILES = {
     'name': 'cicero',
     'version': '0.7.2-3',
     'files': {
         'cicero_0.7.2-3.diff.gz': {
             'md5sum': 'a93661b6a48db48d59ba7d26796fc9ce',
             'name': 'cicero_0.7.2-3.diff.gz',
             'sha256': 'f039c9642fe15c75bed5254315e2a29f9f2700da0e29d9b0729b3ffc46c8971c',  # noqa
             'size': 3964,
             'uri': 'http://deb.debian.org/debian/pool/contrib/c/cicero/cicero_0.7.2-3.diff.gz'  # noqa
         },
         'cicero_0.7.2-3.dsc': {
             'md5sum': 'd5dac83eb9cfc9bb52a15eb618b4670a',
             'name': 'cicero_0.7.2-3.dsc',
             'sha256': '35b7f1048010c67adfd8d70e4961aefd8800eb9a83a4d1cc68088da0009d9a03',  # noqa
             'size': 1864,
             'uri': 'http://deb.debian.org/debian/pool/contrib/c/cicero/cicero_0.7.2-3.dsc'},  # noqa
         'cicero_0.7.2.orig.tar.gz': {
             'md5sum': '4353dede07c5728319ba7f5595a7230a',
             'name': 'cicero_0.7.2.orig.tar.gz',
             'sha256': '63f40f2436ea9f67b44e2d4bd669dbabe90e2635a204526c20e0b3c8ee957786',  # noqa
             'size': 96527,
             'uri': 'http://deb.debian.org/debian/pool/contrib/c/cicero/cicero_0.7.2.orig.tar.gz'  # noqa
         }
     },
 }
 
 PACKAGE_FILES2 = {
     'name': 'cicero',
     'version': '0.7.2-4',
     'files': {
         'cicero_0.7.2-4.diff.gz': {
             'md5sum': '1e7e6fc4a59d57c98082a3af78145734',
             'name': 'cicero_0.7.2-4.diff.gz',
             'sha256': '2e6fa296ee7005473ff58d0971f4fd325617b445671480e9f2cfb738d5dbcd01',  # noqa
             'size': 4038,
             'uri': 'http://deb.debian.org/debian/pool/contrib/c/cicero/cicero_0.7.2-4.diff.gz'  # noqa
         },
         'cicero_0.7.2-4.dsc': {
             'md5sum': '1a6c8855a73b4282bb31d15518f18cde',
             'name': 'cicero_0.7.2-4.dsc',
             'sha256': '913ee52f7093913420de5cbe95d63cfa817f1a1daf997961149501894e754f8b',  # noqa
             'size': 1881,
             'uri': 'http://deb.debian.org/debian/pool/contrib/c/cicero/cicero_0.7.2-4.dsc'},  # noqa
         'cicero_0.7.2.orig.tar.gz': {
             'md5sum': '4353dede07c5728319ba7f5595a7230a',
             'name': 'cicero_0.7.2.orig.tar.gz',
             'sha256': '63f40f2436ea9f67b44e2d4bd669dbabe90e2635a204526c20e0b3c8ee957786',  # noqa
             'size': 96527,
             'uri': 'http://deb.debian.org/debian/pool/contrib/c/cicero/cicero_0.7.2.orig.tar.gz'  # noqa
         }
     }
 }
 
 
 PACKAGE_PER_VERSION = {
     'stretch/contrib/0.7.2-3': PACKAGE_FILES,
 }
 
 
 PACKAGES_PER_VERSION = {
     'stretch/contrib/0.7.2-3': PACKAGE_FILES,
     'buster/contrib/0.7.2-4': PACKAGE_FILES2,
 }
 
 
 def test_debian_first_visit(
         swh_config, requests_mock_datadir):
     """With no prior visit, load a gnu project ends up with 1 snapshot
 
     """
     loader = DebianLoader(
         url='deb://Debian/packages/cicero',
         date='2019-10-12T05:58:09.165557+00:00',
         packages=PACKAGE_PER_VERSION)
 
     actual_load_status = loader.load()
     expected_snapshot_id = '3b6b66e6ee4e7d903a379a882684a2a50480c0b4'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
     stats = get_stats(loader.storage)
     assert {
         'content': 42,
         'directory': 2,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 1,  # all artifacts under 1 revision
         'skipped_content': 0,
         'snapshot': 1
     } == stats
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': {
             'releases/stretch/contrib/0.7.2-3': {
                 'target_type': 'revision',
                 'target': '2807f5b3f84368b4889a9ae827fe85854ffecf07',
             }
         },
     }  # different than the previous loader as no release is done
 
     check_snapshot(expected_snapshot, loader.storage)
 
 
 def test_debian_first_visit_then_another_visit(
         swh_config, requests_mock_datadir):
     """With no prior visit, load a debian project ends up with 1 snapshot
 
     """
     url = 'deb://Debian/packages/cicero'
     loader = DebianLoader(
         url=url,
         date='2019-10-12T05:58:09.165557+00:00',
         packages=PACKAGE_PER_VERSION)
 
     actual_load_status = loader.load()
 
     expected_snapshot_id = '3b6b66e6ee4e7d903a379a882684a2a50480c0b4'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'deb'
 
     stats = get_stats(loader.storage)
     assert {
         'content': 42,
         'directory': 2,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 1,  # all artifacts under 1 revision
         'skipped_content': 0,
         'snapshot': 1
     } == stats
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': {
             'releases/stretch/contrib/0.7.2-3': {
                 'target_type': 'revision',
                 'target': '2807f5b3f84368b4889a9ae827fe85854ffecf07',
             }
         },
     }  # different than the previous loader as no release is done
 
     check_snapshot(expected_snapshot, loader.storage)
 
     # No change in between load
     actual_load_status2 = loader.load()
     assert actual_load_status2['status'] == 'uneventful'
-    origin_visit2 = list(loader.storage.origin_visit_get(url))
-    assert origin_visit2[-1]['status'] == 'full'
-    assert origin_visit2[-1]['type'] == 'deb'
+    origin_visit2 = loader.storage.origin_visit_get_latest(url)
+    assert origin_visit2['status'] == 'full'
+    assert origin_visit2['type'] == 'deb'
 
     stats2 = get_stats(loader.storage)
     assert {
         'content': 42 + 0,
         'directory': 2 + 0,
         'origin': 1,
         'origin_visit': 1 + 1,  # a new visit occurred
         'person': 1,
         'release': 0,
         'revision': 1,
         'skipped_content': 0,
         'snapshot': 1,  # same snapshot across 2 visits
     } == stats2
 
     urls = [
         m.url for m in requests_mock_datadir.request_history
         if m.url.startswith('http://deb.debian.org')
     ]
     # visited each package artifact twice across 2 visits
     assert len(urls) == len(set(urls))
 
 
 def test_uid_to_person():
     uid = 'Someone Name <someone@orga.org>'
     actual_person = uid_to_person(uid)
 
     assert actual_person == {
         'name': 'Someone Name',
         'email': 'someone@orga.org',
         'fullname': uid,
     }
 
 
 def test_prepare_person():
     actual_author = prepare_person({
         'name': 'Someone Name',
         'email': 'someone@orga.org',
         'fullname': 'Someone Name <someone@orga.org>',
     })
 
     assert actual_author == Person(
         name=b'Someone Name',
         email=b'someone@orga.org',
         fullname=b'Someone Name <someone@orga.org>',
     )
 
 
 def test_download_package(datadir, tmpdir, requests_mock_datadir):
     tmpdir = str(tmpdir)  # py3.5 work around (LocalPath issue)
     all_hashes = download_package(PACKAGE_FILES, tmpdir)
     assert all_hashes == {
         'cicero_0.7.2-3.diff.gz': {
             'checksums': {
                 'sha1': '0815282053f21601b0ec4adf7a8fe47eace3c0bc',
                 'sha256': 'f039c9642fe15c75bed5254315e2a29f9f2700da0e29d9b0729b3ffc46c8971c'  # noqa
             },
             'filename': 'cicero_0.7.2-3.diff.gz',
             'length': 3964},
         'cicero_0.7.2-3.dsc': {
             'checksums': {
                 'sha1': 'abbec4e8efbbc80278236e1dd136831eac08accd',
                 'sha256': '35b7f1048010c67adfd8d70e4961aefd8800eb9a83a4d1cc68088da0009d9a03'  # noqa
             },
             'filename': 'cicero_0.7.2-3.dsc',
             'length': 1864},
         'cicero_0.7.2.orig.tar.gz': {
             'checksums': {
                 'sha1': 'a286efd63fe2c9c9f7bb30255c3d6fcdcf390b43',
                 'sha256': '63f40f2436ea9f67b44e2d4bd669dbabe90e2635a204526c20e0b3c8ee957786'  # noqa
             },
             'filename': 'cicero_0.7.2.orig.tar.gz',
             'length': 96527
         }
     }
 
 
 def test_dsc_information_ok():
     fname = 'cicero_0.7.2-3.dsc'
     dsc_url, dsc_name = dsc_information(PACKAGE_FILES)
 
     assert dsc_url == PACKAGE_FILES['files'][fname]['uri']
     assert dsc_name == PACKAGE_FILES['files'][fname]['name']
 
 
 def test_dsc_information_not_found():
     fname = 'cicero_0.7.2-3.dsc'
     package_files = copy.deepcopy(PACKAGE_FILES)
     package_files['files'].pop(fname)
 
     dsc_url, dsc_name = dsc_information(package_files)
 
     assert dsc_url is None
     assert dsc_name is None
 
 
 def test_dsc_information_too_many_dsc_entries():
     # craft an extra dsc file
     fname = 'cicero_0.7.2-3.dsc'
     package_files = copy.deepcopy(PACKAGE_FILES)
     data = package_files['files'][fname]
     fname2 = fname.replace('cicero', 'ciceroo')
     package_files['files'][fname2] = data
 
     with pytest.raises(
             ValueError, match='Package %s_%s references several dsc' % (
                 package_files['name'], package_files['version'])):
         dsc_information(package_files)
 
 
 def test_get_package_metadata(requests_mock_datadir, datadir, tmp_path):
     tmp_path = str(tmp_path)  # py3.5 compat.
     package = PACKAGE_FILES
 
     logger.debug('package: %s', package)
 
     # download the packages
     all_hashes = download_package(package, tmp_path)
 
     # Retrieve information from package
     _, dsc_name = dsc_information(package)
 
     dl_artifacts = [(tmp_path, hashes) for hashes in all_hashes.values()]
 
     # Extract information from package
     extracted_path = extract_package(dl_artifacts, tmp_path)
 
     # Retrieve information on package
     dsc_path = path.join(path.dirname(extracted_path), dsc_name)
     actual_package_info = get_package_metadata(
         package, dsc_path, extracted_path)
 
     logger.debug('actual_package_info: %s', actual_package_info)
 
     assert actual_package_info == {
         'changelog': {
             'date': '2014-10-19T16:52:35+02:00',
             'history': [
                 ('cicero', '0.7.2-2'),
                 ('cicero', '0.7.2-1'),
                 ('cicero', '0.7-1')
             ],
             'person': {
                 'email': 'sthibault@debian.org',
                 'fullname': 'Samuel Thibault <sthibault@debian.org>',
                 'name': 'Samuel Thibault'
             }
         },
         'maintainers': [
             {
                 'email': 'debian-accessibility@lists.debian.org',
                 'fullname': 'Debian Accessibility Team '
                 '<debian-accessibility@lists.debian.org>',
                 'name': 'Debian Accessibility Team'
             },
             {
                 'email': 'sthibault@debian.org',
                 'fullname': 'Samuel Thibault <sthibault@debian.org>',
                 'name': 'Samuel Thibault'
             }
         ],
         'name': 'cicero',
         'version': '0.7.2-3'
     }
 
 
 def test_debian_multiple_packages(swh_config, requests_mock_datadir):
     url = 'deb://Debian/packages/cicero'
     loader = DebianLoader(
         url=url,
         date='2019-10-12T05:58:09.165557+00:00',
         packages=PACKAGES_PER_VERSION)
 
     actual_load_status = loader.load()
     expected_snapshot_id = 'defc19021187f3727293121fcf6c5c82cb923604'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'deb'
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': {
             'releases/stretch/contrib/0.7.2-3': {
                 'target_type': 'revision',
                 'target': '2807f5b3f84368b4889a9ae827fe85854ffecf07',
             },
             'releases/buster/contrib/0.7.2-4': {
                 'target_type': 'revision',
                 'target': '8224139c274c984147ef4b09aa0e462c55a10bd3',
             }
         },
     }
 
     check_snapshot(expected_snapshot, loader.storage)
 
 
 def test_resolve_revision_from_edge_cases():
     """Solving revision with empty data will result in unknown revision
 
     """
     for package_artifacts in [{}, PACKAGE_FILES]:
         actual_revision = resolve_revision_from(
             package_artifacts, {})
         assert actual_revision is None
 
     for known_artifacts in [{}, PACKAGE_FILES]:
         actual_revision = resolve_revision_from(
             {}, known_artifacts)
         assert actual_revision is None
 
     known_package_artifacts = {
         b"(\x07\xf5\xb3\xf8Ch\xb4\x88\x9a\x9a\xe8'\xfe\x85\x85O\xfe\xcf\x07": {
             'extrinsic': {
                 # empty
             },
             # ... removed the unnecessary intermediary data
         }
     }
     assert not resolve_revision_from(known_package_artifacts, PACKAGE_FILES)
 
 
 def test_resolve_revision_from_edge_cases_hit_and_miss():
     """Solving revision with inconsistent data will result in unknown revision
 
     """
     artifact_metadata = PACKAGE_FILES2
     expected_revision_id = b"(\x08\xf5\xb3\xf8Ch\xb4\x88\x9a\x9a\xe8'\xff\x85\x85O\xfe\xcf\x07"  # noqa
     known_package_artifacts = {
         expected_revision_id: {
             'extrinsic': {
                 'raw': PACKAGE_FILES,
             },
             # ... removed the unnecessary intermediary data
         }
     }
 
     actual_revision = resolve_revision_from(
         known_package_artifacts, artifact_metadata
     )
 
     assert actual_revision is None
 
 
 def test_resolve_revision_from():
     """Solving revision with consistent data will solve the revision
 
     """
     artifact_metadata = PACKAGE_FILES
     expected_revision_id = b"(\x07\xf5\xb3\xf8Ch\xb4\x88\x9a\x9a\xe8'\xfe\x85\x85O\xfe\xcf\x07"  # noqa
 
     files = artifact_metadata['files']
     # shuffling dict's keys
     keys = list(files.keys())
     random.shuffle(keys)
     package_files = {
         'files': {k: files[k] for k in keys}
     }
 
     known_package_artifacts = {
         expected_revision_id: {
             'extrinsic': {
                 'raw': package_files,
             },
             # ... removed the unnecessary intermediary data
         }
     }
 
     actual_revision = resolve_revision_from(
         known_package_artifacts, artifact_metadata
     )
 
     assert actual_revision == expected_revision_id
diff --git a/swh/loader/package/deposit/tests/test_deposit.py b/swh/loader/package/deposit/tests/test_deposit.py
index 0ec8922..102e1b5 100644
--- a/swh/loader/package/deposit/tests/test_deposit.py
+++ b/swh/loader/package/deposit/tests/test_deposit.py
@@ -1,205 +1,205 @@
 # Copyright (C) 2019-2020  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 re
 
 
 from swh.model.hashutil import hash_to_bytes
 from swh.loader.package.deposit.loader import DepositLoader
 
 from swh.loader.package.tests.common import (
     check_snapshot, check_metadata_paths, get_stats
 )
 
 from swh.core.pytest_plugin import requests_mock_datadir_factory
 
 
 def test_deposit_init_ok(swh_config, swh_loader_config):
     url = 'some-url'
     deposit_id = 999
     loader = DepositLoader(url, deposit_id)  # Something that does not exist
 
     assert loader.url == url
     assert loader.client is not None
     assert loader.client.base_url == swh_loader_config['deposit']['url']
 
 
 def test_deposit_loading_unknown_deposit(
         swh_config, requests_mock_datadir):
     """Loading an unknown deposit should fail
 
     no origin, no visit, no snapshot
     """
     # private api url form: 'https://deposit.s.o/1/private/hal/666/raw/'
     url = 'some-url'
     unknown_deposit_id = 667
     loader = DepositLoader(url, unknown_deposit_id)  # does not exist
 
     actual_load_status = loader.load()
     assert actual_load_status == {'status': 'failed'}
 
     stats = get_stats(loader.storage)
 
     assert {
         'content': 0,
         'directory': 0,
         'origin': 0,
         'origin_visit': 0,
         'person': 0,
         'release': 0,
         'revision': 0,
         'skipped_content': 0,
         'snapshot': 0,
     } == stats
 
 
 requests_mock_datadir_missing_one = requests_mock_datadir_factory(ignore_urls=[
     'https://deposit.softwareheritage.org/1/private/666/raw/',
 ])
 
 
 def test_deposit_loading_failure_to_retrieve_1_artifact(
         swh_config, requests_mock_datadir_missing_one):
     """Deposit with missing artifact ends up with an uneventful/partial visit
 
     """
     # private api url form: 'https://deposit.s.o/1/private/hal/666/raw/'
     url = 'some-url-2'
     deposit_id = 666
     loader = DepositLoader(url, deposit_id)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'uneventful'
     assert actual_load_status['snapshot_id'] is not None
 
     stats = get_stats(loader.storage)
     assert {
         'content': 0,
         'directory': 0,
         'origin': 1,
         'origin_visit': 1,
         'person': 0,
         'release': 0,
         'revision': 0,
         'skipped_content': 0,
         'snapshot': 1,
     } == stats
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'partial'
     assert origin_visit['type'] == 'deposit'
 
 
 def test_revision_metadata_structure(swh_config, requests_mock_datadir):
     # do not care for deposit update query
     requests_mock_datadir.put(re.compile('https'))
 
     url = 'https://hal-test.archives-ouvertes.fr/some-external-id'
     deposit_id = 666
     loader = DepositLoader(url, deposit_id)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
     assert actual_load_status['snapshot_id'] is not None
     expected_revision_id = hash_to_bytes(
         '637318680351f5d78856d13264faebbd91efe9bb')
     revision = list(loader.storage.revision_get([expected_revision_id]))[0]
 
     assert revision is not None
 
     check_metadata_paths(revision['metadata'], paths=[
         ('extrinsic.provider', str),
         ('extrinsic.when', str),
         ('extrinsic.raw', dict),
         ('original_artifact', list),
     ])
 
     for original_artifact in revision['metadata']['original_artifact']:
         check_metadata_paths(original_artifact, paths=[
             ('filename', str),
             ('length', int),
             ('checksums', dict),
         ])
 
 
 def test_deposit_loading_ok(swh_config, requests_mock_datadir):
     requests_mock_datadir.put(re.compile('https'))  # do not care for put
 
     url = 'https://hal-test.archives-ouvertes.fr/some-external-id'
     deposit_id = 666
     loader = DepositLoader(url, deposit_id)
 
     actual_load_status = loader.load()
     expected_snapshot_id = 'b2b327b33dc85818bd23c3ccda8b7e675a66ecbd'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id,
     }
 
     stats = get_stats(loader.storage)
     assert {
         'content': 303,
         'directory': 12,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 1,
         'skipped_content': 0,
         'snapshot': 1,
     } == stats
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'deposit'
 
     expected_branches = {
         'HEAD': {
             'target': '637318680351f5d78856d13264faebbd91efe9bb',
             'target_type': 'revision',
         },
     }
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': expected_branches,
     }
     check_snapshot(expected_snapshot, storage=loader.storage)
 
     # check metadata
 
     tool = {
         "name": "swh-deposit",
         "version": "0.0.1",
         "configuration": {
             "sword_version": "2",
         }
     }
 
     tool = loader.storage.tool_get(tool)
     assert tool is not None
     assert tool['id'] is not None
 
     provider = {
         "provider_name": "hal",
         "provider_type": "deposit_client",
         "provider_url": "https://hal-test.archives-ouvertes.fr/",
         "metadata": None,
     }
 
     provider = loader.storage.metadata_provider_get_by(provider)
     assert provider is not None
     assert provider['id'] is not None
 
     metadata = list(loader.storage.origin_metadata_get_by(
         url, provider_type='deposit_client'))
     assert metadata is not None
     assert isinstance(metadata, list)
     assert len(metadata) == 1
     metadata0 = metadata[0]
 
     assert metadata0['provider_id'] == provider['id']
     assert metadata0['provider_type'] == 'deposit_client'
     assert metadata0['tool_id'] == tool['id']
diff --git a/swh/loader/package/functional/tests/test_functional.py b/swh/loader/package/functional/tests/test_functional.py
index 35bf10d..408d8af 100644
--- a/swh/loader/package/functional/tests/test_functional.py
+++ b/swh/loader/package/functional/tests/test_functional.py
@@ -1,276 +1,276 @@
 # Copyright (C) 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 pytest
 from json.decoder import JSONDecodeError
 
 from swh.loader.package.functional.loader import (
     FunctionalLoader, retrieve_sources
 )
 
 from swh.loader.package.tests.common import (
     get_stats, check_snapshot
 )
 
 sources_url = 'https://nix-community.github.io/nixpkgs-swh/sources.json'
 
 
 def test_retrieve_sources(swh_config, requests_mock_datadir):
     j = retrieve_sources(sources_url)
     assert "sources" in j.keys()
     assert len(j["sources"]) == 2
 
 
 def test_retrieve_non_existing(swh_config, requests_mock_datadir):
     with pytest.raises(ValueError):
         FunctionalLoader('https://non-existing-url')
 
 
 def test_retrieve_non_json(swh_config, requests_mock_datadir):
     with pytest.raises(JSONDecodeError):
         FunctionalLoader('https://example.com/file.txt')
 
 
 def test_loader_one_visit(swh_config, requests_mock_datadir):
     loader = FunctionalLoader(sources_url)
     res = loader.load()
     assert res['status'] == 'eventful'
 
     stats = get_stats(loader.storage)
     assert {
         'content': 1,
         'directory': 3,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 1,
         'skipped_content': 0,
         'snapshot': 1
     } == stats
 
-    origin_visit = next(loader.storage.origin_visit_get(sources_url))
+    origin_visit = loader.storage.origin_visit_get_latest(sources_url)
     # The visit is partial because urls pointing to non tarball file
     # are not handled yet
     assert origin_visit['status'] == 'partial'
     assert origin_visit['type'] == 'functional'
 
 
 def test_uncompress_failure(swh_config, requests_mock_datadir):
     """Non tarball files are currently not supported and the uncompress
     function fails on such kind of files.
 
     However, even in this case of failure (because of the url
     https://example.com/file.txt), a snapshot and a visit has to be
     created (with a status partial since all files are not archived).
 
     """
     loader = FunctionalLoader(sources_url)
     loader_status = loader.load()
 
     urls = [s['url'][0] for s in loader.sources]
     assert "https://example.com/file.txt" in urls
     assert loader_status['status'] == 'eventful'
 
-    origin_visit = next(loader.storage.origin_visit_get(sources_url))
+    origin_visit = loader.storage.origin_visit_get_latest(sources_url)
     # The visit is partial because urls pointing to non tarball files
     # are not handled yet
     assert origin_visit['status'] == 'partial'
 
 
 def test_loader_incremental(swh_config, requests_mock_datadir):
     """Ensure a second visit do not download artifact already
     downloaded by the previous visit.
 
     """
     loader = FunctionalLoader(sources_url)
     load_status = loader.load()
 
     loader = FunctionalLoader(sources_url)
     loader.load()
     expected_snapshot_id = '0c5881c74283793ebe9a09a105a9381e41380383'
     assert load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
     expected_branches = {
         'evaluation': {
             'target': 'cc4e04c26672dd74e5fd0fecb78b435fb55368f7',
             'target_type': 'revision'
         },
         'https://github.com/owner-1/repository-1/revision-1.tgz': {
             'target': '488ad4e7b8e2511258725063cf43a2b897c503b4',
             'target_type': 'revision'
         },
     }
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': expected_branches,
     }
     check_snapshot(expected_snapshot, storage=loader.storage)
 
     urls = [
         m.url for m in requests_mock_datadir.request_history
         if m.url == ('https://github.com/owner-1/repository-1/revision-1.tgz')
     ]
     # The artifact
     # 'https://github.com/owner-1/repository-1/revision-1.tgz' is only
     # visited one time
     assert len(urls) == 1
 
 
 def test_loader_two_visits(swh_config, requests_mock_datadir_visits):
     """To ensure there is only one origin, but two visits, two revisions
     and two snapshots are created.
 
     The first visit creates a snapshot containing one tarball. The
     second visit creates a snapshot containing the same tarball and
     another tarball.
 
     """
     loader = FunctionalLoader(sources_url)
     load_status = loader.load()
     expected_snapshot_id = '0c5881c74283793ebe9a09a105a9381e41380383'
     assert load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
     expected_branches = {
         'evaluation': {
             'target': 'cc4e04c26672dd74e5fd0fecb78b435fb55368f7',
             'target_type': 'revision'
         },
         'https://github.com/owner-1/repository-1/revision-1.tgz': {
             'target': '488ad4e7b8e2511258725063cf43a2b897c503b4',
             'target_type': 'revision'
         }
     }
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': expected_branches,
     }
     check_snapshot(expected_snapshot, storage=loader.storage)
 
     stats = get_stats(loader.storage)
     assert {
         'content': 1,
         'directory': 3,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 1,
         'skipped_content': 0,
         'snapshot': 1
     } == stats
 
     loader = FunctionalLoader(sources_url)
     load_status = loader.load()
     expected_snapshot_id = 'b0bfa75cbd0cc90aac3b9e95fb0f59c731176d97'
     assert load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
     # This ensures visits are incremental. Indeed, if we request a
     # second time an url, because of the requests_mock_datadir_visits
     # fixture, the file has to end with `_visit1`.
     expected_branches = {
         'evaluation': {
             'target': '602140776b2ce6c9159bcf52ada73a297c063d5e',
             'target_type': 'revision'
         },
         'https://github.com/owner-1/repository-1/revision-1.tgz': {
             'target': '488ad4e7b8e2511258725063cf43a2b897c503b4',
             'target_type': 'revision'
         },
         'https://github.com/owner-2/repository-1/revision-1.tgz': {
             'target': '85e0bad74e33e390aaeb74f139853ae3863ee544',
             'target_type': 'revision'
         }
     }
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': expected_branches,
     }
     check_snapshot(expected_snapshot, storage=loader.storage)
 
     stats = get_stats(loader.storage)
     assert {
         'content': 2,
         'directory': 5,
         'origin': 1,
         'origin_visit': 2,
         'person': 1,
         'release': 0,
         'revision': 2,
         'skipped_content': 0,
         'snapshot': 2
     } == stats
 
 
 def test_resolve_revision_from(swh_config, requests_mock_datadir):
     loader = FunctionalLoader(sources_url)
 
     known_artifacts = {
         'id1': {'extrinsic': {'raw': {'url': "url1"}}},
         'id2': {'extrinsic': {'raw': {'url': "url2"}}}
         }
 
     metadata = {'url': 'url1'}
     assert loader.resolve_revision_from(known_artifacts, metadata) == 'id1'
     metadata = {'url': 'url3'}
     assert loader.resolve_revision_from(known_artifacts, metadata) == None # noqa
 
 
 def test_evaluation_branch(swh_config, requests_mock_datadir):
     loader = FunctionalLoader(sources_url)
     res = loader.load()
     assert res['status'] == 'eventful'
 
     expected_branches = {
         'https://github.com/owner-1/repository-1/revision-1.tgz': {
             'target': '488ad4e7b8e2511258725063cf43a2b897c503b4',
             'target_type': 'revision',
         },
         'evaluation': {
             'target': 'cc4e04c26672dd74e5fd0fecb78b435fb55368f7',
             'target_type': 'revision',
         },
     }
 
     expected_snapshot = {
         'id': '0c5881c74283793ebe9a09a105a9381e41380383',
         'branches': expected_branches,
     }
 
     check_snapshot(expected_snapshot, storage=loader.storage)
 
 
 def test_eoferror(swh_config, requests_mock_datadir):
     """Load a truncated archive which is invalid to make the uncompress
     function raising the exception EOFError. We then check if a
     snapshot is created, meaning this error is well managed.
 
     """
     sources = "https://nix-community.github.io/nixpkgs-swh/sources-EOFError.json" # noqa
     loader = FunctionalLoader(sources)
     loader.load()
 
     expected_branches = {
         'evaluation': {
             'target': 'cc4e04c26672dd74e5fd0fecb78b435fb55368f7',
             'target_type': 'revision',
         },
     }
     expected_snapshot = {
         'id': '4257fa2350168c6bfec726a06452ea27a2c0cb33',
         'branches': expected_branches,
     }
 
     check_snapshot(expected_snapshot, storage=loader.storage)
diff --git a/swh/loader/package/npm/tests/test_npm.py b/swh/loader/package/npm/tests/test_npm.py
index 495275e..cc2ae32 100644
--- a/swh/loader/package/npm/tests/test_npm.py
+++ b/swh/loader/package/npm/tests/test_npm.py
@@ -1,608 +1,608 @@
 # Copyright (C) 2019-2020  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 json
 import os
 import pytest
 
 from swh.model.hashutil import hash_to_bytes
 from swh.model.model import Person
 
 from swh.loader.package.npm.loader import (
     NpmLoader, extract_npm_package_author,
     artifact_to_revision_id
 )
 from swh.loader.package.tests.common import (
     check_snapshot, check_metadata_paths, get_stats
 )
 
 
 def test_extract_npm_package_author(datadir):
     package_metadata_filepath = os.path.join(
         datadir, 'https_replicate.npmjs.com', 'org_visit1')
 
     with open(package_metadata_filepath) as json_file:
         package_metadata = json.load(json_file)
 
     extract_npm_package_author(package_metadata['versions']['0.0.2']) == \
         Person(
             fullname=b'mooz <stillpedant@gmail.com>',
             name=b'mooz',
             email=b'stillpedant@gmail.com'
         )
 
     assert (
         extract_npm_package_author(package_metadata['versions']['0.0.3']) ==
         Person(
             fullname=b'Masafumi Oyamada <stillpedant@gmail.com>',
             name=b'Masafumi Oyamada',
             email=b'stillpedant@gmail.com'
         )
     )
 
     package_json = json.loads('''
     {
         "name": "highlightjs-line-numbers.js",
         "version": "2.7.0",
         "description": "Highlight.js line numbers plugin.",
         "main": "src/highlightjs-line-numbers.js",
         "dependencies": {},
         "devDependencies": {
             "gulp": "^4.0.0",
             "gulp-rename": "^1.4.0",
             "gulp-replace": "^0.6.1",
             "gulp-uglify": "^1.2.0"
         },
         "repository": {
             "type": "git",
             "url": "https://github.com/wcoder/highlightjs-line-numbers.js.git"
         },
         "author": "Yauheni Pakala <evgeniy.pakalo@gmail.com>",
         "license": "MIT",
         "bugs": {
             "url": "https://github.com/wcoder/highlightjs-line-numbers.js/issues"
         },
         "homepage": "http://wcoder.github.io/highlightjs-line-numbers.js/"
     }''') # noqa
 
     assert extract_npm_package_author(package_json) == \
         Person(
             fullname=b'Yauheni Pakala <evgeniy.pakalo@gmail.com>',
             name=b'Yauheni Pakala',
             email=b'evgeniy.pakalo@gmail.com'
         )
 
     package_json = json.loads('''
     {
         "name": "3-way-diff",
         "version": "0.0.1",
         "description": "3-way diffing of JavaScript objects",
         "main": "index.js",
         "authors": [
             {
                 "name": "Shawn Walsh",
                 "url": "https://github.com/shawnpwalsh"
             },
             {
                 "name": "Markham F Rollins IV",
                 "url": "https://github.com/mrollinsiv"
             }
         ],
         "keywords": [
             "3-way diff",
             "3 way diff",
             "three-way diff",
             "three way diff"
         ],
         "devDependencies": {
             "babel-core": "^6.20.0",
             "babel-preset-es2015": "^6.18.0",
             "mocha": "^3.0.2"
         },
         "dependencies": {
             "lodash": "^4.15.0"
         }
     }''')
 
     assert extract_npm_package_author(package_json) == \
         Person(
             fullname=b'Shawn Walsh',
             name=b'Shawn Walsh',
             email=None
         )
 
     package_json = json.loads('''
     {
         "name": "yfe-ynpm",
         "version": "1.0.0",
         "homepage": "http://gitlab.ywwl.com/yfe/yfe-ynpm",
         "repository": {
             "type": "git",
             "url": "git@gitlab.ywwl.com:yfe/yfe-ynpm.git"
         },
         "author": [
             "fengmk2 <fengmk2@gmail.com> (https://fengmk2.com)",
             "xufuzi <xufuzi@ywwl.com> (https://7993.org)"
         ],
         "license": "MIT"
     }''')
 
     assert extract_npm_package_author(package_json) == \
         Person(
             fullname=b'fengmk2 <fengmk2@gmail.com> (https://fengmk2.com)',
             name=b'fengmk2',
             email=b'fengmk2@gmail.com',
         )
 
     package_json = json.loads('''
     {
         "name": "umi-plugin-whale",
         "version": "0.0.8",
         "description": "Internal contract component",
         "authors": {
             "name": "xiaohuoni",
             "email": "448627663@qq.com"
         },
         "repository": "alitajs/whale",
         "devDependencies": {
             "np": "^3.0.4",
             "umi-tools": "*"
         },
         "license": "MIT"
     }''')
 
     assert extract_npm_package_author(package_json) == \
         Person(
             fullname=b'xiaohuoni <448627663@qq.com>',
             name=b'xiaohuoni',
             email=b'448627663@qq.com'
         )
 
 
 def normalize_hashes(hashes):
     if isinstance(hashes, str):
         return hash_to_bytes(hashes)
     if isinstance(hashes, list):
         return [hash_to_bytes(x) for x in hashes]
     return {hash_to_bytes(k): hash_to_bytes(v) for k, v in hashes.items()}
 
 
 _expected_new_contents_first_visit = normalize_hashes([
     '4ce3058e16ab3d7e077f65aabf855c34895bf17c',
     '858c3ceee84c8311adc808f8cdb30d233ddc9d18',
     '0fa33b4f5a4e0496da6843a38ff1af8b61541996',
     '85a410f8ef8eb8920f2c384a9555566ad4a2e21b',
     '9163ac8025923d5a45aaac482262893955c9b37b',
     '692cf623b8dd2c5df2c2998fd95ae4ec99882fb4',
     '18c03aac6d3e910efb20039c15d70ab5e0297101',
     '41265c42446aac17ca769e67d1704f99e5a1394d',
     '783ff33f5882813dca9239452c4a7cadd4dba778',
     'b029cfb85107aee4590c2434a3329bfcf36f8fa1',
     '112d1900b4c2e3e9351050d1b542c9744f9793f3',
     '5439bbc4bd9a996f1a38244e6892b71850bc98fd',
     'd83097a2f994b503185adf4e719d154123150159',
     'd0939b4898e83090ee55fd9d8a60e312cfadfbaf',
     'b3523a26f7147e4af40d9d462adaae6d49eda13e',
     'cd065fb435d6fb204a8871bcd623d0d0e673088c',
     '2854a40855ad839a54f4b08f5cff0cf52fca4399',
     'b8a53bbaac34ebb8c6169d11a4b9f13b05c583fe',
     '0f73d56e1cf480bded8a1ecf20ec6fc53c574713',
     '0d9882b2dfafdce31f4e77fe307d41a44a74cefe',
     '585fc5caab9ead178a327d3660d35851db713df1',
     'e8cd41a48d79101977e3036a87aeb1aac730686f',
     '5414efaef33cceb9f3c9eb5c4cc1682cd62d14f7',
     '9c3cc2763bf9e9e37067d3607302c4776502df98',
     '3649a68410e354c83cd4a38b66bd314de4c8f5c9',
     'e96ed0c091de1ebdf587104eaf63400d1974a1fe',
     '078ca03d2f99e4e6eab16f7b75fbb7afb699c86c',
     '38de737da99514de6559ff163c988198bc91367a',
 ])
 
 _expected_new_directories_first_visit = normalize_hashes([
     '3370d20d6f96dc1c9e50f083e2134881db110f4f',
     '42753c0c2ab00c4501b552ac4671c68f3cf5aece',
     'd7895533ef5edbcffdea3f057d9fef3a1ef845ce',
     '80579be563e2ef3e385226fe7a3f079b377f142c',
     '3b0ddc6a9e58b4b53c222da4e27b280b6cda591c',
     'bcad03ce58ac136f26f000990fc9064e559fe1c0',
     '5fc7e82a1bc72e074665c6078c6d3fad2f13d7ca',
     'e3cd26beba9b1e02f6762ef54bd9ac80cc5f25fd',
     '584b5b4b6cf7f038095e820b99386a9c232de931',
     '184c8d6d0d242f2b1792ef9d3bf396a5434b7f7a',
     'bb5f4ee143c970367eb409f2e4c1104898048b9d',
     '1b95491047add1103db0dfdfa84a9735dcb11e88',
     'a00c6de13471a2d66e64aca140ddb21ef5521e62',
     '5ce6c1cd5cda2d546db513aaad8c72a44c7771e2',
     'c337091e349b6ac10d38a49cdf8c2401ef9bb0f2',
     '202fafcd7c0f8230e89d5496ad7f44ab12b807bf',
     '775cc516543be86c15c1dc172f49c0d4e6e78235',
     'ff3d1ead85a14f891e8b3fa3a89de39db1b8de2e',
 ])
 
 _expected_new_revisions_first_visit = normalize_hashes({
     'd8a1c7474d2956ac598a19f0f27d52f7015f117e':
     '42753c0c2ab00c4501b552ac4671c68f3cf5aece',
     '5f9eb78af37ffd12949f235e86fac04898f9f72a':
     '3370d20d6f96dc1c9e50f083e2134881db110f4f',
     'ba019b192bdb94bd0b5bd68b3a5f92b5acc2239a':
     'd7895533ef5edbcffdea3f057d9fef3a1ef845ce'}
 )
 
 
 def package_url(package):
     return 'https://www.npmjs.com/package/%s' % package
 
 
 def package_metadata_url(package):
     return 'https://replicate.npmjs.com/%s/' % package
 
 
 def test_revision_metadata_structure(swh_config, requests_mock_datadir):
     package = 'org'
     loader = NpmLoader(package_url(package))
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
     assert actual_load_status['snapshot_id'] is not None
 
     expected_revision_id = hash_to_bytes(
         'd8a1c7474d2956ac598a19f0f27d52f7015f117e')
     revision = list(loader.storage.revision_get([expected_revision_id]))[0]
 
     assert revision is not None
 
     check_metadata_paths(revision['metadata'], paths=[
         ('intrinsic.tool', str),
         ('intrinsic.raw', dict),
         ('extrinsic.provider', str),
         ('extrinsic.when', str),
         ('extrinsic.raw', dict),
         ('original_artifact', list),
     ])
 
     for original_artifact in revision['metadata']['original_artifact']:
         check_metadata_paths(original_artifact, paths=[
             ('filename', str),
             ('length', int),
             ('checksums', dict),
         ])
 
 
 def test_npm_loader_first_visit(swh_config, requests_mock_datadir):
 
     package = 'org'
     loader = NpmLoader(package_url(package))
 
     actual_load_status = loader.load()
     expected_snapshot_id = 'd0587e1195aed5a8800411a008f2f2d627f18e2d'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
     stats = get_stats(loader.storage)
 
     assert {
         'content': len(_expected_new_contents_first_visit),
         'directory': len(_expected_new_directories_first_visit),
         'origin': 1,
         'origin_visit': 1,
         'person': 2,
         'release': 0,
         'revision': len(_expected_new_revisions_first_visit),
         'skipped_content': 0,
         'snapshot': 1,
     } == stats
 
     assert len(list(loader.storage.content_get(
         _expected_new_contents_first_visit))) == len(
             _expected_new_contents_first_visit)
 
     assert list(loader.storage.directory_missing(
         _expected_new_directories_first_visit)) == []
 
     assert list(loader.storage.revision_missing(
         _expected_new_revisions_first_visit)) == []
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': {
             'HEAD': {
                 'target': 'releases/0.0.4',
                 'target_type': 'alias'
             },
             'releases/0.0.2': {
                 'target': 'd8a1c7474d2956ac598a19f0f27d52f7015f117e',
                 'target_type': 'revision'
             },
             'releases/0.0.3': {
                 'target': '5f9eb78af37ffd12949f235e86fac04898f9f72a',
                 'target_type': 'revision'
             },
             'releases/0.0.4': {
                 'target': 'ba019b192bdb94bd0b5bd68b3a5f92b5acc2239a',
                 'target_type': 'revision'
             }
         }
     }
     check_snapshot(expected_snapshot, loader.storage)
 
 
 def test_npm_loader_incremental_visit(
         swh_config, requests_mock_datadir_visits):
     package = 'org'
     url = package_url(package)
     loader = NpmLoader(url)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
     assert actual_load_status['status'] is not None
-    origin_visit = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'npm'
 
     stats = get_stats(loader.storage)
 
     assert {
         'content': len(_expected_new_contents_first_visit),
         'directory': len(_expected_new_directories_first_visit),
         'origin': 1,
         'origin_visit': 1,
         'person': 2,
         'release': 0,
         'revision': len(_expected_new_revisions_first_visit),
         'skipped_content': 0,
         'snapshot': 1,
     } == stats
 
     loader._info = None  # reset loader internal state
     actual_load_status2 = loader.load()
     assert actual_load_status2['status'] == 'eventful'
     snap_id2 = actual_load_status2['snapshot_id']
     assert snap_id2 is not None
     assert snap_id2 != actual_load_status['snapshot_id']
 
-    origin_visit2 = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit2 = loader.storage.origin_visit_get_latest(url)
     assert origin_visit2['status'] == 'full'
     assert origin_visit2['type'] == 'npm'
 
     stats = get_stats(loader.storage)
 
     assert {  # 3 new releases artifacts
         'content': len(_expected_new_contents_first_visit) + 14,
         'directory': len(_expected_new_directories_first_visit) + 15,
         'origin': 1,
         'origin_visit': 2,
         'person': 2,
         'release': 0,
         'revision': len(_expected_new_revisions_first_visit) + 3,
         'skipped_content': 0,
         'snapshot': 2,
     } == stats
 
     urls = [
         m.url for m in requests_mock_datadir_visits.request_history
         if m.url.startswith('https://registry.npmjs.org')
     ]
     assert len(urls) == len(set(urls))  # we visited each artifact once across
 
 
 @pytest.mark.usefixtures('requests_mock_datadir')
 def test_npm_loader_version_divergence(swh_config):
     package = '@aller_shared'
     url = package_url(package)
     loader = NpmLoader(url)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
     assert actual_load_status['status'] is not None
-    origin_visit = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'npm'
 
     stats = get_stats(loader.storage)
 
     assert {  # 1 new releases artifacts
         'content': 534,
         'directory': 153,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 2,
         'skipped_content': 0,
         'snapshot': 1,
     } == stats
 
     expected_snapshot = {
         'id': 'b11ebac8c9d0c9e5063a2df693a18e3aba4b2f92',
         'branches': {
             'HEAD': {
                 'target_type': 'alias',
                 'target': 'releases/0.1.0'
             },
             'releases/0.1.0': {
                 'target_type': 'revision',
                 'target': '845673bfe8cbd31b1eaf757745a964137e6f9116',
             },
             'releases/0.1.1-alpha.14': {
                 'target_type': 'revision',
                 'target': '05181c12cd8c22035dd31155656826b85745da37',
             },
         },
     }
     check_snapshot(expected_snapshot, loader.storage)
 
 
 def test_npm_artifact_to_revision_id_none():
     """Current loader version should stop soon if nothing can be found
 
     """
     artifact_metadata = {
         'dist': {
             'shasum': '05181c12cd8c22035dd31155656826b85745da37',
         },
     }
 
     known_artifacts = {
         'b11ebac8c9d0c9e5063a2df693a18e3aba4b2f92': {},
     }
 
     assert artifact_to_revision_id(known_artifacts, artifact_metadata) is None
 
 
 def test_npm_artifact_to_revision_id_old_loader_version():
     """Current loader version should solve old metadata scheme
 
     """
     artifact_metadata = {
         'dist': {
             'shasum': '05181c12cd8c22035dd31155656826b85745da37',
         }
     }
 
     known_artifacts = {
         hash_to_bytes('b11ebac8c9d0c9e5063a2df693a18e3aba4b2f92'): {
             'package_source': {
                 'sha1': "something-wrong"
             }
         },
         hash_to_bytes('845673bfe8cbd31b1eaf757745a964137e6f9116'): {
             'package_source': {
                 'sha1': '05181c12cd8c22035dd31155656826b85745da37',
             }
         }
 
     }
 
     assert artifact_to_revision_id(known_artifacts, artifact_metadata) \
         == hash_to_bytes('845673bfe8cbd31b1eaf757745a964137e6f9116')
 
 
 def test_npm_artifact_to_revision_id_current_loader_version():
     """Current loader version should be able to solve current metadata scheme
 
     """
     artifact_metadata = {
         'dist': {
             'shasum': '05181c12cd8c22035dd31155656826b85745da37',
         }
     }
 
     known_artifacts = {
         hash_to_bytes('b11ebac8c9d0c9e5063a2df693a18e3aba4b2f92'): {
             'original_artifact': [{
                 'checksums': {
                     'sha1': "05181c12cd8c22035dd31155656826b85745da37"
                 },
             }],
         },
         hash_to_bytes('845673bfe8cbd31b1eaf757745a964137e6f9116'): {
             'original_artifact': [{
                 'checksums': {
                     'sha1': 'something-wrong'
                 },
             }],
         },
     }
 
     assert artifact_to_revision_id(known_artifacts, artifact_metadata) \
         == hash_to_bytes('b11ebac8c9d0c9e5063a2df693a18e3aba4b2f92')
 
 
 def test_npm_artifact_with_no_intrinsic_metadata(
         swh_config, requests_mock_datadir):
     """Skip artifact with no intrinsic metadata during ingestion
 
     """
     package = 'nativescript-telerik-analytics'
     url = package_url(package)
     loader = NpmLoader(url)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
 
     # no branch as one artifact without any intrinsic metadata
     expected_snapshot = {
         'id': '1a8893e6a86f444e8be8e7bda6cb34fb1735a00e',
         'branches': {},
     }
     check_snapshot(expected_snapshot, loader.storage)
 
-    origin_visit = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'npm'
 
 
 def test_npm_artifact_with_no_upload_time(swh_config, requests_mock_datadir):
     """With no time upload, artifact is skipped
 
     """
     package = 'jammit-no-time'
     url = package_url(package)
     loader = NpmLoader(url)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'uneventful'
 
     # no branch as one artifact without any intrinsic metadata
     expected_snapshot = {
         'id': '1a8893e6a86f444e8be8e7bda6cb34fb1735a00e',
         'branches': {},
     }
     check_snapshot(expected_snapshot, loader.storage)
 
-    origin_visit = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'partial'
     assert origin_visit['type'] == 'npm'
 
 
 def test_npm_artifact_use_mtime_if_no_time(swh_config, requests_mock_datadir):
     """With no time upload, artifact is skipped
 
     """
     package = 'jammit-express'
     url = package_url(package)
     loader = NpmLoader(url)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
 
     # artifact is used
     expected_snapshot = {
         'id': 'd6e08e19159f77983242877c373c75222d5ae9dd',
         'branches': {
             'HEAD': {
                 'target_type': 'alias',
                 'target': 'releases/0.0.1'
             },
             'releases/0.0.1': {
                 'target_type': 'revision',
                 'target': '9e4dd2b40d1b46b70917c0949aa2195c823a648e',
             }
         }
     }
     check_snapshot(expected_snapshot, loader.storage)
 
-    origin_visit = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'npm'
 
 
 def test_npm_no_artifact(swh_config, requests_mock_datadir):
     """If no artifacts at all is found for origin, the visit fails completely
 
     """
     package = 'catify'
     url = package_url(package)
     loader = NpmLoader(url)
     actual_load_status = loader.load()
     assert actual_load_status == {
         'status': 'failed',
     }
 
     origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'partial'
     assert origin_visit['type'] == 'npm'
diff --git a/swh/loader/package/pypi/tests/test_pypi.py b/swh/loader/package/pypi/tests/test_pypi.py
index 6979813..9c38c39 100644
--- a/swh/loader/package/pypi/tests/test_pypi.py
+++ b/swh/loader/package/pypi/tests/test_pypi.py
@@ -1,834 +1,834 @@
 # Copyright (C) 2019-2020 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 os
 
 from os import path
 
 import pytest
 
 from unittest.mock import patch
 
 from swh.core.tarball import uncompress
 from swh.core.pytest_plugin import requests_mock_datadir_factory
 from swh.model.hashutil import hash_to_bytes
 from swh.model.model import Person
 
 from swh.loader.package.pypi.loader import (
     PyPILoader, pypi_api_url, author, extract_intrinsic_metadata,
     artifact_to_revision_id
 )
 from swh.loader.package.tests.common import (
     check_snapshot, check_metadata_paths, get_stats
 )
 
 
 def test_author_basic():
     data = {
         'author': "i-am-groot",
         'author_email': 'iam@groot.org',
     }
     actual_author = author(data)
 
     expected_author = Person(
         fullname=b'i-am-groot <iam@groot.org>',
         name=b'i-am-groot',
         email=b'iam@groot.org',
     )
 
     assert actual_author == expected_author
 
 
 def test_author_empty_email():
     data = {
         'author': 'i-am-groot',
         'author_email': '',
     }
     actual_author = author(data)
 
     expected_author = Person(
         fullname=b'i-am-groot',
         name=b'i-am-groot',
         email=b'',
     )
 
     assert actual_author == expected_author
 
 
 def test_author_empty_name():
     data = {
         'author': "",
         'author_email': 'iam@groot.org',
     }
     actual_author = author(data)
 
     expected_author = Person(
         fullname=b' <iam@groot.org>',
         name=b'',
         email=b'iam@groot.org',
     )
 
     assert actual_author == expected_author
 
 
 def test_author_malformed():
     data = {
         'author': "['pierre', 'paul', 'jacques']",
         'author_email': None,
     }
 
     actual_author = author(data)
 
     expected_author = Person(
         fullname=b"['pierre', 'paul', 'jacques']",
         name=b"['pierre', 'paul', 'jacques']",
         email=None,
     )
 
     assert actual_author == expected_author
 
 
 def test_author_malformed_2():
     data = {
         'author': '[marie, jeanne]',
         'author_email': '[marie@some, jeanne@thing]',
     }
 
     actual_author = author(data)
 
     expected_author = Person(
         fullname=b'[marie, jeanne] <[marie@some, jeanne@thing]>',
         name=b'[marie, jeanne]',
         email=b'[marie@some, jeanne@thing]',
     )
 
     assert actual_author == expected_author
 
 
 def test_author_malformed_3():
     data = {
         'author': '[marie, jeanne, pierre]',
         'author_email': '[marie@somewhere.org, jeanne@somewhere.org]',
     }
 
     actual_author = author(data)
 
     expected_author = Person(
         fullname=(
             b'[marie, jeanne, pierre] '
             b'<[marie@somewhere.org, jeanne@somewhere.org]>'
         ),
         name=b'[marie, jeanne, pierre]',
         email=b'[marie@somewhere.org, jeanne@somewhere.org]',
     )
 
     actual_author == expected_author
 
 
 # configuration error #
 
 def test_badly_configured_loader_raise(monkeypatch):
     """Badly configured loader should raise"""
     monkeypatch.delenv('SWH_CONFIG_FILENAME', raising=False)
     with pytest.raises(ValueError) as e:
         PyPILoader(url='some-url')
 
     assert 'Misconfiguration' in e.value.args[0]
 
 
 def test_pypi_api_url():
     """Compute pypi api url from the pypi project url should be ok"""
     url = pypi_api_url('https://pypi.org/project/requests')
     assert url == 'https://pypi.org/pypi/requests/json'
 
 
 def test_pypi_api_url_with_slash():
     """Compute pypi api url from the pypi project url should be ok"""
     url = pypi_api_url('https://pypi.org/project/requests/')
     assert url == 'https://pypi.org/pypi/requests/json'
 
 
 @pytest.mark.fs
 def test_extract_intrinsic_metadata(tmp_path, datadir):
     """Parsing existing archive's PKG-INFO should yield results"""
     uncompressed_archive_path = str(tmp_path)
     archive_path = path.join(
         datadir, 'https_files.pythonhosted.org', '0805nexter-1.1.0.zip')
     uncompress(archive_path, dest=uncompressed_archive_path)
 
     actual_metadata = extract_intrinsic_metadata(uncompressed_archive_path)
     expected_metadata = {
         'metadata_version': '1.0',
         'name': '0805nexter',
         'version': '1.1.0',
         'summary': 'a simple printer of nested lest',
         'home_page': 'http://www.hp.com',
         'author': 'hgtkpython',
         'author_email': '2868989685@qq.com',
         'platforms': ['UNKNOWN'],
     }
 
     assert actual_metadata == expected_metadata
 
 
 @pytest.mark.fs
 def test_extract_intrinsic_metadata_failures(tmp_path):
     """Parsing inexistent path/archive/PKG-INFO yield None"""
     tmp_path = str(tmp_path)  # py3.5 work around (PosixPath issue)
     # inexistent first level path
     assert extract_intrinsic_metadata('/something-inexistent') == {}
     # inexistent second level path (as expected by pypi archives)
     assert extract_intrinsic_metadata(tmp_path) == {}
     # inexistent PKG-INFO within second level path
     existing_path_no_pkginfo = path.join(tmp_path, 'something')
     os.mkdir(existing_path_no_pkginfo)
     assert extract_intrinsic_metadata(tmp_path) == {}
 
 
 # LOADER SCENARIO #
 
 # "edge" cases (for the same origin) #
 
 
 # no release artifact:
 # {visit full, status: uneventful, no contents, etc...}
 requests_mock_datadir_missing_all = requests_mock_datadir_factory(ignore_urls=[
     'https://files.pythonhosted.org/packages/ec/65/c0116953c9a3f47de89e71964d6c7b0c783b01f29fa3390584dbf3046b4d/0805nexter-1.1.0.zip',  # noqa
     'https://files.pythonhosted.org/packages/c4/a0/4562cda161dc4ecbbe9e2a11eb365400c0461845c5be70d73869786809c4/0805nexter-1.2.0.zip',  # noqa
 ])
 
 
 def test_no_release_artifact(swh_config, requests_mock_datadir_missing_all):
     """Load a pypi project with all artifacts missing ends up with no snapshot
 
     """
     url = 'https://pypi.org/project/0805nexter'
     loader = PyPILoader(url)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'uneventful'
     assert actual_load_status['snapshot_id'] is not None
 
     stats = get_stats(loader.storage)
     assert {
         'content': 0,
         'directory': 0,
         'origin': 1,
         'origin_visit': 1,
         'person': 0,
         'release': 0,
         'revision': 0,
         'skipped_content': 0,
         'snapshot': 1,
     } == stats
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'partial'
     assert origin_visit['type'] == 'pypi'
 
 
 # problem during loading:
 # {visit: partial, status: uneventful, no snapshot}
 
 
 def test_release_with_traceback(swh_config, requests_mock_datadir):
     url = 'https://pypi.org/project/0805nexter'
     with patch('swh.loader.package.pypi.loader.PyPILoader.last_snapshot',
                side_effect=ValueError('Fake problem to fail the visit')):
         loader = PyPILoader(url)
 
         actual_load_status = loader.load()
         assert actual_load_status == {'status': 'failed'}
 
         stats = get_stats(loader.storage)
 
         assert {
             'content': 0,
             'directory': 0,
             'origin': 1,
             'origin_visit': 1,
             'person': 0,
             'release': 0,
             'revision': 0,
             'skipped_content': 0,
             'snapshot': 0,
         } == stats
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'partial'
     assert origin_visit['type'] == 'pypi'
 
 
 # problem during loading: failure early enough in between swh contents...
 # some contents (contents, directories, etc...) have been written in storage
 # {visit: partial, status: eventful, no snapshot}
 
 # problem during loading: failure late enough we can have snapshots (some
 # revisions are written in storage already)
 # {visit: partial, status: eventful, snapshot}
 
 # "normal" cases (for the same origin) #
 
 
 requests_mock_datadir_missing_one = requests_mock_datadir_factory(ignore_urls=[
     'https://files.pythonhosted.org/packages/ec/65/c0116953c9a3f47de89e71964d6c7b0c783b01f29fa3390584dbf3046b4d/0805nexter-1.1.0.zip',  # noqa
 ])
 
 # some missing release artifacts:
 # {visit partial, status: eventful, 1 snapshot}
 
 
 def test_revision_metadata_structure(swh_config, requests_mock_datadir):
     url = 'https://pypi.org/project/0805nexter'
     loader = PyPILoader(url)
 
     actual_load_status = loader.load()
     assert actual_load_status['status'] == 'eventful'
     assert actual_load_status['snapshot_id'] is not None
 
     expected_revision_id = hash_to_bytes(
         'e445da4da22b31bfebb6ffc4383dbf839a074d21')
     revision = list(loader.storage.revision_get([expected_revision_id]))[0]
 
     assert revision is not None
 
     check_metadata_paths(revision['metadata'], paths=[
         ('intrinsic.tool', str),
         ('intrinsic.raw', dict),
         ('extrinsic.provider', str),
         ('extrinsic.when', str),
         ('extrinsic.raw', dict),
         ('original_artifact', list),
     ])
 
     for original_artifact in revision['metadata']['original_artifact']:
         check_metadata_paths(original_artifact, paths=[
             ('filename', str),
             ('length', int),
             ('checksums', dict),
         ])
 
 
 def test_visit_with_missing_artifact(
         swh_config, requests_mock_datadir_missing_one):
     """Load a pypi project with some missing artifacts ends up with 1 snapshot
 
     """
     url = 'https://pypi.org/project/0805nexter'
     loader = PyPILoader(url)
 
     actual_load_status = loader.load()
     expected_snapshot_id = 'dd0e4201a232b1c104433741dbf45895b8ac9355'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
     stats = get_stats(loader.storage)
 
     assert {
         'content': 3,
         'directory': 2,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 1,
         'skipped_content': 0,
         'snapshot': 1
     } == stats
 
     expected_contents = map(hash_to_bytes, [
         '405859113963cb7a797642b45f171d6360425d16',
         'e5686aa568fdb1d19d7f1329267082fe40482d31',
         '83ecf6ec1114fd260ca7a833a2d165e71258c338',
     ])
 
     assert list(loader.storage.content_missing_per_sha1(expected_contents))\
         == []
 
     expected_dirs = map(hash_to_bytes, [
         'b178b66bd22383d5f16f4f5c923d39ca798861b4',
         'c3a58f8b57433a4b56caaa5033ae2e0931405338',
     ])
 
     assert list(loader.storage.directory_missing(expected_dirs)) == []
 
     # {revision hash: directory hash}
     expected_revs = {
         hash_to_bytes('e445da4da22b31bfebb6ffc4383dbf839a074d21'): hash_to_bytes('b178b66bd22383d5f16f4f5c923d39ca798861b4'),  # noqa
     }
     assert list(loader.storage.revision_missing(expected_revs)) == []
 
     expected_branches = {
         'releases/1.2.0': {
             'target': 'e445da4da22b31bfebb6ffc4383dbf839a074d21',
             'target_type': 'revision',
         },
         'HEAD': {
             'target': 'releases/1.2.0',
             'target_type': 'alias',
         },
     }
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': expected_branches,
     }
     check_snapshot(expected_snapshot, storage=loader.storage)
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'partial'
     assert origin_visit['type'] == 'pypi'
 
 
 def test_visit_with_1_release_artifact(swh_config, requests_mock_datadir):
     """With no prior visit, load a pypi project ends up with 1 snapshot
 
     """
     url = 'https://pypi.org/project/0805nexter'
     loader = PyPILoader(url)
 
     actual_load_status = loader.load()
     expected_snapshot_id = 'ba6e158ada75d0b3cfb209ffdf6daa4ed34a227a'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
     stats = get_stats(loader.storage)
     assert {
         'content': 6,
         'directory': 4,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 2,
         'skipped_content': 0,
         'snapshot': 1
     } == stats
 
     expected_contents = map(hash_to_bytes, [
         'a61e24cdfdab3bb7817f6be85d37a3e666b34566',
         '938c33483285fd8ad57f15497f538320df82aeb8',
         'a27576d60e08c94a05006d2e6d540c0fdb5f38c8',
         '405859113963cb7a797642b45f171d6360425d16',
         'e5686aa568fdb1d19d7f1329267082fe40482d31',
         '83ecf6ec1114fd260ca7a833a2d165e71258c338',
     ])
 
     assert list(loader.storage.content_missing_per_sha1(expected_contents))\
         == []
 
     expected_dirs = map(hash_to_bytes, [
         '05219ba38bc542d4345d5638af1ed56c7d43ca7d',
         'cf019eb456cf6f78d8c4674596f1c9a97ece8f44',
         'b178b66bd22383d5f16f4f5c923d39ca798861b4',
         'c3a58f8b57433a4b56caaa5033ae2e0931405338',
     ])
 
     assert list(loader.storage.directory_missing(expected_dirs)) == []
 
     # {revision hash: directory hash}
     expected_revs = {
         hash_to_bytes('4c99891f93b81450385777235a37b5e966dd1571'): hash_to_bytes('05219ba38bc542d4345d5638af1ed56c7d43ca7d'),  # noqa
         hash_to_bytes('e445da4da22b31bfebb6ffc4383dbf839a074d21'): hash_to_bytes('b178b66bd22383d5f16f4f5c923d39ca798861b4'),  # noqa
     }
     assert list(loader.storage.revision_missing(expected_revs)) == []
 
     expected_branches = {
         'releases/1.1.0': {
             'target': '4c99891f93b81450385777235a37b5e966dd1571',
             'target_type': 'revision',
         },
         'releases/1.2.0': {
             'target': 'e445da4da22b31bfebb6ffc4383dbf839a074d21',
             'target_type': 'revision',
         },
         'HEAD': {
             'target': 'releases/1.2.0',
             'target_type': 'alias',
         },
     }
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': expected_branches,
     }
     check_snapshot(expected_snapshot, loader.storage)
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'pypi'
 
 
 def test_multiple_visits_with_no_change(swh_config, requests_mock_datadir):
     """Multiple visits with no changes results in 1 same snapshot
 
     """
     url = 'https://pypi.org/project/0805nexter'
     loader = PyPILoader(url)
 
     actual_load_status = loader.load()
     snapshot_id = 'ba6e158ada75d0b3cfb209ffdf6daa4ed34a227a'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': snapshot_id,
     }
 
     stats = get_stats(loader.storage)
 
     assert {
         'content': 6,
         'directory': 4,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 2,
         'skipped_content': 0,
         'snapshot': 1
     } == stats
 
     expected_branches = {
         'releases/1.1.0': {
             'target': '4c99891f93b81450385777235a37b5e966dd1571',
             'target_type': 'revision',
         },
         'releases/1.2.0': {
             'target': 'e445da4da22b31bfebb6ffc4383dbf839a074d21',
             'target_type': 'revision',
         },
         'HEAD': {
             'target': 'releases/1.2.0',
             'target_type': 'alias',
         },
     }
 
     expected_snapshot = {
         'id': snapshot_id,
         'branches': expected_branches,
     }
     check_snapshot(expected_snapshot, loader.storage)
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'pypi'
 
     actual_load_status2 = loader.load()
     assert actual_load_status2 == {
         'status': 'uneventful',
         'snapshot_id': actual_load_status2['snapshot_id']
     }
 
     stats2 = get_stats(loader.storage)
     expected_stats2 = stats.copy()
     expected_stats2['origin_visit'] = 1 + 1
     assert expected_stats2 == stats2
 
     # same snapshot
     actual_snapshot_id = origin_visit['snapshot']
     assert actual_snapshot_id == hash_to_bytes(snapshot_id)
 
 
 def test_incremental_visit(swh_config, requests_mock_datadir_visits):
     """With prior visit, 2nd load will result with a different snapshot
 
     """
     url = 'https://pypi.org/project/0805nexter'
     loader = PyPILoader(url)
 
     visit1_actual_load_status = loader.load()
     visit1_stats = get_stats(loader.storage)
     expected_snapshot_id = 'ba6e158ada75d0b3cfb209ffdf6daa4ed34a227a'
     assert visit1_actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id
     }
 
-    origin_visit1 = next(loader.storage.origin_visit_get(url))
+    origin_visit1 = loader.storage.origin_visit_get_latest(url)
     assert origin_visit1['status'] == 'full'
     assert origin_visit1['type'] == 'pypi'
 
     assert {
         'content': 6,
         'directory': 4,
         'origin': 1,
         'origin_visit': 1,
         'person': 1,
         'release': 0,
         'revision': 2,
         'skipped_content': 0,
         'snapshot': 1
     } == visit1_stats
 
     # Reset internal state
     loader._info = None
 
     visit2_actual_load_status = loader.load()
     visit2_stats = get_stats(loader.storage)
 
     assert visit2_actual_load_status['status'] == 'eventful'
     expected_snapshot_id2 = '2e5149a7b0725d18231a37b342e9b7c4e121f283'
     assert visit2_actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id2
     }
 
     visits = list(loader.storage.origin_visit_get(url))
     assert len(visits) == 2
     assert visits[1]['status'] == 'full'
     assert visits[1]['type'] == 'pypi'
 
     assert {
         'content': 6 + 1,     # 1 more content
         'directory': 4 + 2,   # 2 more directories
         'origin': 1,
         'origin_visit': 1 + 1,
         'person': 1,
         'release': 0,
         'revision': 2 + 1,    # 1 more revision
         'skipped_content': 0,
         'snapshot': 1 + 1,    # 1 more snapshot
     } == visit2_stats
 
     expected_contents = map(hash_to_bytes, [
         'a61e24cdfdab3bb7817f6be85d37a3e666b34566',
         '938c33483285fd8ad57f15497f538320df82aeb8',
         'a27576d60e08c94a05006d2e6d540c0fdb5f38c8',
         '405859113963cb7a797642b45f171d6360425d16',
         'e5686aa568fdb1d19d7f1329267082fe40482d31',
         '83ecf6ec1114fd260ca7a833a2d165e71258c338',
         '92689fa2b7fb4d4fc6fb195bf73a50c87c030639'
     ])
 
     assert list(loader.storage.content_missing_per_sha1(expected_contents))\
         == []
 
     expected_dirs = map(hash_to_bytes, [
         '05219ba38bc542d4345d5638af1ed56c7d43ca7d',
         'cf019eb456cf6f78d8c4674596f1c9a97ece8f44',
         'b178b66bd22383d5f16f4f5c923d39ca798861b4',
         'c3a58f8b57433a4b56caaa5033ae2e0931405338',
         'e226e7e4ad03b4fc1403d69a18ebdd6f2edd2b3a',
         '52604d46843b898f5a43208045d09fcf8731631b',
 
     ])
 
     assert list(loader.storage.directory_missing(expected_dirs)) == []
 
     # {revision hash: directory hash}
     expected_revs = {
         hash_to_bytes('4c99891f93b81450385777235a37b5e966dd1571'): hash_to_bytes('05219ba38bc542d4345d5638af1ed56c7d43ca7d'),  # noqa
         hash_to_bytes('e445da4da22b31bfebb6ffc4383dbf839a074d21'): hash_to_bytes('b178b66bd22383d5f16f4f5c923d39ca798861b4'),  # noqa
         hash_to_bytes('51247143b01445c9348afa9edfae31bf7c5d86b1'): hash_to_bytes('e226e7e4ad03b4fc1403d69a18ebdd6f2edd2b3a'),  # noqa
     }
 
     assert list(loader.storage.revision_missing(expected_revs)) == []
 
     expected_branches = {
         'releases/1.1.0': {
             'target': '4c99891f93b81450385777235a37b5e966dd1571',
             'target_type': 'revision',
         },
         'releases/1.2.0': {
             'target': 'e445da4da22b31bfebb6ffc4383dbf839a074d21',
             'target_type': 'revision',
         },
         'releases/1.3.0': {
             'target': '51247143b01445c9348afa9edfae31bf7c5d86b1',
             'target_type': 'revision',
         },
         'HEAD': {
             'target': 'releases/1.3.0',
             'target_type': 'alias',
         },
     }
     expected_snapshot = {
         'id': expected_snapshot_id2,
         'branches': expected_branches,
     }
 
     check_snapshot(expected_snapshot, loader.storage)
 
-    origin_visit = list(loader.storage.origin_visit_get(url))[-1]
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'pypi'
 
     urls = [
         m.url for m in requests_mock_datadir_visits.request_history
         if m.url.startswith('https://files.pythonhosted.org')
     ]
     # visited each artifact once across 2 visits
     assert len(urls) == len(set(urls))
 
 
 # release artifact, no new artifact
 # {visit full, status uneventful, same snapshot as before}
 
 # release artifact, old artifact with different checksums
 # {visit full, status full, new snapshot with shared history and some new
 # different history}
 
 # release with multiple sdist artifacts per pypi "version"
 # snapshot branch output is different
 
 def test_visit_1_release_with_2_artifacts(swh_config, requests_mock_datadir):
     """With no prior visit, load a pypi project ends up with 1 snapshot
 
     """
     url = 'https://pypi.org/project/nexter'
     loader = PyPILoader(url)
 
     actual_load_status = loader.load()
     expected_snapshot_id = 'a27e638a4dad6fbfa273c6ebec1c4bf320fb84c6'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id,
     }
 
     expected_branches = {
         'releases/1.1.0/nexter-1.1.0.zip': {
             'target': '4c99891f93b81450385777235a37b5e966dd1571',
             'target_type': 'revision',
         },
         'releases/1.1.0/nexter-1.1.0.tar.gz': {
             'target': '0bf88f5760cca7665d0af4d6575d9301134fe11a',
             'target_type': 'revision',
         },
     }
 
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': expected_branches,
     }
     check_snapshot(expected_snapshot, loader.storage)
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'pypi'
 
 
 def test_pypi_artifact_to_revision_id_none():
     """Current loader version should stop soon if nothing can be found
 
     """
     artifact_metadata = {
         'digests': {
             'sha256': '6975816f2c5ad4046acc676ba112f2fff945b01522d63948531f11f11e0892ec',  # noqa
         },
     }
 
     assert artifact_to_revision_id({}, artifact_metadata) is None
 
     known_artifacts = {
         'b11ebac8c9d0c9e5063a2df693a18e3aba4b2f92': {
             'original_artifact': {
                 'sha256': 'something-irrelevant',
             },
         },
     }
 
     assert artifact_to_revision_id(known_artifacts, artifact_metadata) is None
 
 
 def test_pypi_artifact_to_revision_id_old_loader_version():
     """Current loader version should solve old metadata scheme
 
     """
     artifact_metadata = {
         'digests': {
             'sha256': '6975816f2c5ad4046acc676ba112f2fff945b01522d63948531f11f11e0892ec',  # noqa
         }
     }
 
     known_artifacts = {
         hash_to_bytes('b11ebac8c9d0c9e5063a2df693a18e3aba4b2f92'): {
             'original_artifact': {
                 'sha256': "something-wrong",
              },
         },
         hash_to_bytes('845673bfe8cbd31b1eaf757745a964137e6f9116'): {
             'original_artifact': {
                 'sha256': '6975816f2c5ad4046acc676ba112f2fff945b01522d63948531f11f11e0892ec',  # noqa
              },
         }
     }
 
     assert artifact_to_revision_id(known_artifacts, artifact_metadata) \
         == hash_to_bytes('845673bfe8cbd31b1eaf757745a964137e6f9116')
 
 
 def test_pypi_artifact_to_revision_id_current_loader_version():
     """Current loader version should be able to solve current metadata scheme
 
     """
     artifact_metadata = {
         'digests': {
             'sha256': '6975816f2c5ad4046acc676ba112f2fff945b01522d63948531f11f11e0892ec', # noqa
         }
     }
 
     known_artifacts = {
         hash_to_bytes('b11ebac8c9d0c9e5063a2df693a18e3aba4b2f92'): {
             'original_artifact': [{
                 'checksums': {
                     'sha256': '6975816f2c5ad4046acc676ba112f2fff945b01522d63948531f11f11e0892ec',  # noqa
                 },
             }],
         },
         hash_to_bytes('845673bfe8cbd31b1eaf757745a964137e6f9116'): {
             'original_artifact': [{
                 'checksums': {
                     'sha256': 'something-wrong'
                 },
             }],
         },
     }
 
     assert artifact_to_revision_id(known_artifacts, artifact_metadata) \
         == hash_to_bytes('b11ebac8c9d0c9e5063a2df693a18e3aba4b2f92')
 
 
 def test_pypi_artifact_to_revision_id_failures():
     with pytest.raises(KeyError, match='sha256'):
         artifact_metadata = {
             'digests': {},
         }
         assert artifact_to_revision_id({}, artifact_metadata)
 
     with pytest.raises(KeyError, match='digests'):
         artifact_metadata = {
             'something': 'wrong',
         }
         assert artifact_to_revision_id({}, artifact_metadata)
 
 
 def test_pypi_artifact_with_no_intrinsic_metadata(
         swh_config, requests_mock_datadir):
     """Skip artifact with no intrinsic metadata during ingestion
 
     """
     url = 'https://pypi.org/project/upymenu'
     loader = PyPILoader(url)
 
     actual_load_status = loader.load()
     expected_snapshot_id = '1a8893e6a86f444e8be8e7bda6cb34fb1735a00e'
     assert actual_load_status == {
         'status': 'eventful',
         'snapshot_id': expected_snapshot_id,
     }
 
     # no branch as one artifact without any intrinsic metadata
     expected_snapshot = {
         'id': expected_snapshot_id,
         'branches': {}
     }
     check_snapshot(expected_snapshot, loader.storage)
 
-    origin_visit = next(loader.storage.origin_visit_get(url))
+    origin_visit = loader.storage.origin_visit_get_latest(url)
     assert origin_visit['status'] == 'full'
     assert origin_visit['type'] == 'pypi'