vault.tests: Make postgresql fixture faster

This reuse the swh.core.db.db_utils postgresql_fact fixture (which inits the db then truncate tables in between test calls). This makes the tests faster.

Basic benchmark:

|---------+--------------+-----------+-----------------------|
| machine | before (min) | after (s) | Using                 |
|---------+--------------+-----------+-----------------------|
| laptop  |      1:11.02 | 20.811    | `time tox`            |
| jenkins |         1:14 | 26        | jenkins output report |
|---------+--------------+-----------+-----------------------|

Test Plan

tox

---

Migrated from D4310 (view on Phabricator)

swh/vault/tests/conftest.py

-import glob
+# 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 os
-import subprocess
 from typing import Any, Dict
 
 import pkg_resources.extern.packaging.version
 import pytest
-from pytest_postgresql import factories
 
-from swh.core.utils import numfile_sortkey as sortkey
+from swh.core.db.pytest_plugin import postgresql_fact
 from swh.storage.tests import SQL_DIR as STORAGE_SQL_DIR
+import swh.vault
 from swh.vault import get_vault
-from swh.vault.tests import SQL_DIR
 
 os.environ["LC_ALL"] = "C.UTF-8"
 
@@ -35,17 +37,25 @@ def db_url(name, postgresql_proc):
     )
 
 
-postgresql2 = factories.postgresql("postgresql_proc", "tests2")
+VAULT_SQL_DIR = os.path.join(os.path.dirname(swh.vault.__file__), "sql")
+
+
+postgres_vault = postgresql_fact(
+    "postgresql_proc", db_name="vault", dump_files=f"{VAULT_SQL_DIR}/*.sql"
+)
+postgres_storage = postgresql_fact(
+    "postgresql_proc", db_name="storage", dump_files=f"{STORAGE_SQL_DIR}/*.sql"
+)
 
 
 @pytest.fixture
-def swh_vault_config(postgresql, postgresql2, tmp_path) -> Dict[str, Any]:
+def swh_vault_config(postgres_vault, postgres_storage, tmp_path) -> Dict[str, Any]:
     tmp_path = str(tmp_path)
     return {
-        "db": postgresql.dsn,
+        "db": postgres_vault.dsn,
         "storage": {
             "cls": "local",
-            "db": postgresql2.dsn,
+            "db": postgres_storage.dsn,
             "objstorage": {
                 "cls": "pathslicing",
                 "args": {"root": tmp_path, "slicing": "0:1/1:5",},
@@ -60,26 +70,7 @@ def swh_vault_config(postgresql, postgresql2, tmp_path) -> Dict[str, Any]:
 
 
 @pytest.fixture
-def swh_vault(request, swh_vault_config, postgresql, postgresql2, tmp_path):
-    for sql_dir, pg in ((SQL_DIR, postgresql), (STORAGE_SQL_DIR, postgresql2)):
-        dump_files = os.path.join(sql_dir, "*.sql")
-        all_dump_files = sorted(glob.glob(dump_files), key=sortkey)
-
-        for fname in all_dump_files:
-            subprocess.check_call(
-                [
-                    "psql",
-                    "--quiet",
-                    "--no-psqlrc",
-                    "-v",
-                    "ON_ERROR_STOP=1",
-                    "-d",
-                    pg.dsn,
-                    "-f",
-                    fname,
-                ]
-            )
-
+def swh_vault(request, swh_vault_config):
     return get_vault("local", **swh_vault_config)