ensure that sqlite databases enforce foreign key constraints (#432)

src/foxops/database/engine.py

@@ -0,0 +1,17 @@
+from sqlalchemy import Pool
+from sqlalchemy.event import listen
+from sqlalchemy.ext.asyncio import AsyncEngine, create_async_engine
+
+
+def create_engine(connection_string: str) -> AsyncEngine:
+    # enforce foreign key constraints on SQLite:
+    # https://docs.sqlalchemy.org/en/20/dialects/sqlite.html#foreign-key-support
+    def set_sqlite_pragma(dbapi_connection, connection_record):
+        cursor = dbapi_connection.cursor()
+        cursor.execute("PRAGMA foreign_keys=ON")
+        cursor.close()
+
+    if connection_string.startswith("sqlite+"):
+        listen(Pool, "connect", set_sqlite_pragma)
+
+    return create_async_engine(connection_string, future=True, echo=False, pool_pre_ping=True)

src/foxops/database/repositories/change.py

@@ -9,6 +9,7 @@
 
 from foxops.database.schema import change, incarnations
 from foxops.errors import FoxopsError, IncarnationNotFoundError
+from foxops.logger import get_logger
 
 
 class ChangeConflictError(FoxopsError):
@@ -90,6 +91,8 @@ class ChangeRepository:
     def __init__(self, engine: AsyncEngine) -> None:
         self.engine = engine
 
+        self.log = get_logger(component=self.__class__.__name__)
+
     async def create_change(
         self,
         incarnation_id: int,
@@ -154,6 +157,14 @@ async def create_incarnation_with_first_change(
         requested_data: str,
         template_data_full: str,
     ) -> ChangeInDB:
+        logger = self.log.bind(function="create_incarnation_with_first_change")
+        logger.debug(
+            "starting transaction",
+            incarnation_repository=incarnation_repository,
+            target_directory=target_directory,
+            template_repository=template_repository,
+        )
+
         async with self.engine.begin() as conn:
             query_insert_incarnation = (
                 insert(incarnations)
@@ -167,6 +178,8 @@ async def create_incarnation_with_first_change(
             result = await conn.execute(query_insert_incarnation)
             incarnation_id = result.one()[0]
 
+            logger.debug("inserted incarnation", incarnation_id=incarnation_id)
+
             query_insert_change = (
                 insert(change)
                 .values(

src/foxops/dependencies.py

@@ -3,8 +3,9 @@
 from fastapi import Depends, HTTPException, Request, status
 from fastapi.openapi.models import APIKey, APIKeyIn
 from fastapi.security.base import SecurityBase
-from sqlalchemy.ext.asyncio import AsyncEngine, create_async_engine
+from sqlalchemy.ext.asyncio import AsyncEngine
 
+from foxops.database.engine import create_engine
 from foxops.database.repositories.change import ChangeRepository
 from foxops.database.repositories.incarnation.repository import IncarnationRepository
 from foxops.hosters import Hoster
@@ -41,7 +42,7 @@ def get_database_engine(request: Request, settings: DatabaseSettings = Depends(g
     if hasattr(request.app.state, "database"):
         return request.app.state.database
 
-    async_engine = create_async_engine(settings.url.get_secret_value(), future=True, echo=False, pool_pre_ping=True)
+    async_engine = create_engine(settings.url.get_secret_value())
 
     request.app.state.database = async_engine
     return async_engine

tests/conftest.py

@@ -9,10 +9,10 @@
 import pytest
 from fastapi import FastAPI
 from httpx import AsyncClient
-from sqlalchemy import Engine, event
-from sqlalchemy.ext.asyncio import AsyncEngine, create_async_engine
+from sqlalchemy.ext.asyncio import AsyncEngine
 
 from foxops.__main__ import create_app
+from foxops.database.engine import create_engine
 from foxops.database.repositories.change import ChangeRepository
 from foxops.database.repositories.incarnation.repository import IncarnationRepository
 from foxops.database.schema import meta
@@ -60,15 +60,8 @@ def use_testing_gitconfig():
 
 @pytest.fixture(name="test_async_engine")
 async def test_async_engine() -> AsyncGenerator[AsyncEngine, None]:
-    # enforce foreign key constraints on SQLite:
-    # https://docs.sqlalchemy.org/en/20/dialects/sqlite.html#foreign-key-support
-    @event.listens_for(Engine, "connect")
-    def set_sqlite_pragma(dbapi_connection, connection_record):
-        cursor = dbapi_connection.cursor()
-        cursor.execute("PRAGMA foreign_keys=ON")
-        cursor.close()
-
-    async_engine = create_async_engine("sqlite+aiosqlite://", future=True, echo=False, pool_pre_ping=True)
+    async_engine = create_engine("sqlite+aiosqlite://")
+
     async with async_engine.begin() as conn:
         await conn.run_sync(meta.create_all)
 

tests/database/test_incarnation_repository.py

@@ -1,5 +1,6 @@
 from pytest import fixture, raises
 
+from foxops.database.repositories.change import ChangeRepository
 from foxops.database.repositories.incarnation.errors import (
     IncarnationAlreadyExistsError,
     IncarnationNotFoundError,
@@ -93,12 +94,13 @@ async def test_list_returns_existing_incarnations(incarnation_repository: Incarn
 
 
 async def test_delete_by_id_returns_none_when_deleting_existing_incarnation(
-    incarnation_repository: IncarnationRepository, incarnation_id: int
+    incarnation_repository: IncarnationRepository, change_repository: ChangeRepository, incarnation_id: int
 ):
     # WHEN
     await incarnation_repository.delete_by_id(incarnation_id)
 
     # THEN
+    assert len(await change_repository.list_changes(incarnation_id)) == 0
     with raises(IncarnationNotFoundError):
         await incarnation_repository.get_by_id(incarnation_id)