feat(database): add managed backup and offline restore (#6359)

tests/test_database_backup_initializer.py

@@ -0,0 +1,40 @@
+from pathlib import Path
+from types import SimpleNamespace
+from unittest.mock import Mock
+
+from app.application.database import get_database_governance
+from app.startup import database as startup_database
+
+
+def test_builder_uses_cached_engine_as_database_fact_source(monkeypatch) -> None:
+    engine = SimpleNamespace(dialect=SimpleNamespace(name="sqlite"))
+    backend = Mock(db_type="sqlite", suffix=".db")
+    sqlite_backend = Mock(return_value=backend)
+    monkeypatch.setattr(startup_database, "get_engine", lambda: engine)
+    monkeypatch.setattr(startup_database, "SQLiteBackupBackend", sqlite_backend)
+    monkeypatch.setattr(startup_database.settings, "DB_TYPE", "postgresql")
+
+    startup_database.build_database_governance()
+
+    sqlite_backend.assert_called_once_with(engine)
+
+
+def test_backup_policy_reads_current_path_and_retention(tmp_path: Path, monkeypatch) -> None:
+    monkeypatch.setattr(startup_database.settings, "DB_BACKUP_PATH", str(tmp_path))
+    monkeypatch.setattr(startup_database.settings, "DB_BACKUP_RETENTION_DAYS", 7)
+    monkeypatch.setattr(startup_database.settings, "DB_BACKUP_MAX_COUNT", 5)
+
+    policy = startup_database.read_backup_policy()
+
+    assert policy.root == tmp_path
+    assert policy.retention_days == 7
+    assert policy.max_count == 5
+
+
+def test_configure_registers_one_database_governance(monkeypatch) -> None:
+    governance = Mock()
+    monkeypatch.setattr(startup_database, "build_database_governance", lambda: governance)
+
+    startup_database.configure_database()
+
+    assert get_database_governance() is governance