fix(workbench): serialize events and target work order sync

tests/unit/test_workbench_event_order.py

@@ -0,0 +1,49 @@
+from contextlib import asynccontextmanager
+from types import SimpleNamespace
+from unittest.mock import AsyncMock, Mock
+from uuid import uuid4
+
+import pytest
+
+from app.infra.db.postgresql.operational_tasks import OperationalTaskRepository
+from app.infra.db.postgresql.task_alerts import TaskAlertRepository
+from app.infra.db.postgresql.workbench_events import (
+    EVENT_ORDER_LOCK, lock_event_transaction_sync,
+)
+
+
+@pytest.fixture
+def anyio_backend():
+    return "asyncio"
+
+
+@pytest.mark.anyio
+@pytest.mark.parametrize("repository", [OperationalTaskRepository, TaskAlertRepository])
+@pytest.mark.parametrize("database", ["tjwater_v2", "other_project"])
+async def test_event_order_lock_precedes_business_writes_and_is_v2_only(repository, database):
+    @asynccontextmanager
+    async def transaction():
+        yield
+
+    connection = SimpleNamespace(
+        info=SimpleNamespace(dbname=database), execute=AsyncMock(), transaction=transaction,
+    )
+    async with repository(connection, uuid4()).transaction():
+        if database == "tjwater_v2":
+            connection.execute.assert_awaited_once_with(
+                "SELECT pg_advisory_xact_lock(hashtextextended(%s,0))", (EVENT_ORDER_LOCK,),
+            )
+        else:
+            connection.execute.assert_not_awaited()
+
+
+def test_sync_producers_use_same_database_scoped_lock():
+    connection = SimpleNamespace(info=SimpleNamespace(dbname="tjwater_v2"), execute=Mock())
+    lock_event_transaction_sync(connection)
+    connection.execute.assert_called_once_with(
+        "SELECT pg_advisory_xact_lock(hashtextextended(%s,0))", (EVENT_ORDER_LOCK,),
+    )
+    connection.info.dbname = "other_project"
+    connection.execute.reset_mock()
+    lock_event_transaction_sync(connection)
+    connection.execute.assert_not_called()