Initial commit: stateful OpenStack API laboratory simulator.

Ship Keystone auth, multi-service handlers (Yoga→Dalmatian), Compose/Helm
packaging, API contract packs, and pytest/Pulumi coverage labs.

tests/unit/test_db_primitives.py

@@ -0,0 +1,59 @@
+"""Database primitive behavior independent of PostgreSQL."""
+
+import asyncpg  # type: ignore[import-untyped]
+import pytest
+
+from app.db.primitives import (
+    ConflictError,
+    DatabaseOperationError,
+    ReferenceError,
+    RetryPolicy,
+    TransientDatabaseError,
+    map_database_error,
+    require_affected,
+    retry_transient,
+)
+
+
+def test_error_mapping_is_stable_and_safe() -> None:
+    assert isinstance(map_database_error(asyncpg.UniqueViolationError("secret")), ConflictError)
+    assert isinstance(
+        map_database_error(asyncpg.ForeignKeyViolationError("secret")), ReferenceError
+    )
+    assert isinstance(
+        map_database_error(asyncpg.SerializationError("secret")), TransientDatabaseError
+    )
+    assert "secret" not in str(map_database_error(asyncpg.PostgresError("secret")))
+
+
+def test_affected_row_checks() -> None:
+    require_affected("UPDATE 1")
+    with pytest.raises(DatabaseOperationError, match="expected 1"):
+        require_affected("UPDATE 0")
+    with pytest.raises(DatabaseOperationError, match="unrecognized"):
+        require_affected("BROKEN")
+
+
+async def test_transient_retry_is_bounded() -> None:
+    calls = 0
+
+    async def operation() -> str:
+        nonlocal calls
+        calls += 1
+        if calls < 3:
+            raise TransientDatabaseError("retry")
+        return "ok"
+
+    assert await retry_transient(operation, RetryPolicy(attempts=3, base_delay_seconds=0)) == "ok"
+    assert calls == 3
+
+
+async def test_transient_retry_propagates_final_failure() -> None:
+    async def operation() -> None:
+        raise TransientDatabaseError("retry")
+
+    with pytest.raises(TransientDatabaseError):
+        await retry_transient(operation, RetryPolicy(attempts=2, base_delay_seconds=0))
+
+    with pytest.raises(ValueError, match="positive"):
+        await retry_transient(operation, RetryPolicy(attempts=0))