fix: skip redundant refresh/reload round trips in create() and update()

src/fastapi_toolsets/crud/factory.py

@@ -52,7 +52,6 @@ from .search import (
     search_field_keys,
 )
 
-
 _ForUpdateMode: TypeAlias = bool | Literal["nowait", "skip_locked"]
 
 
@@ -174,17 +173,30 @@ class AsyncCrud(Generic[ModelType]):
         return cls.default_load_options
 
     @classmethod
-    async def _reload_with_options(
-        cls: type[Self], session: AsyncSession, instance: ModelType
+    def _capture_pk_values(cls: type[Self], instance: ModelType) -> dict[str, Any]:
+        """Capture PK values off instance — call before commit expires attributes."""
+        return {
+            cast(str, col.key): getattr(instance, cast(str, col.key))
+            for col in cls.model.__mapper__.primary_key
+        }
+
+    @classmethod
+    async def _reload_with_options_by_pk(
+        cls: type[Self], session: AsyncSession, pk_values: dict[str, Any]
     ) -> ModelType:
-        """Re-query instance by PK with default_load_options applied."""
-        mapper = cls.model.__mapper__
+        """Re-query by previously captured PK values, with default_load_options applied."""
+        # Only called when cls.default_load_options is set (see call sites).
         pk_filters = [
-            getattr(cls.model, cast(str, col.key))
-            == getattr(instance, cast(str, col.key))
-            for col in mapper.primary_key
+            getattr(cls.model, key) == value for key, value in pk_values.items()
         ]
-        return await cls.get(session, filters=pk_filters)
+        q = select(cls.model).where(and_(*pk_filters))
+        q = q.execution_options(populate_existing=True)
+        q = q.options(*cast(Sequence[ExecutableOption], cls.default_load_options))
+        result = await session.execute(q)
+        item = result.unique().scalar_one_or_none()
+        if item is None:  # pragma: no cover — row was just flushed in this transaction
+            raise NotFoundError()
+        return cast(ModelType, item)
 
     @classmethod
     async def _resolve_m2m(
@@ -738,9 +750,14 @@ class AsyncCrud(Generic[ModelType]):
                     setattr(db_model, rel_attr, related_instances)
 
             session.add(db_model)
-        await session.refresh(db_model)
+            pk_values: dict[str, Any] | None = None
             if cls.default_load_options:
-            db_model = await cls._reload_with_options(session, db_model)
+                await session.flush()
+                pk_values = cls._capture_pk_values(db_model)
+        if pk_values is not None:
+            db_model = await cls._reload_with_options_by_pk(session, pk_values)
+        else:
+            await session.refresh(db_model)
         result = cast(ModelType, db_model)
         if schema:
             return Response(data=schema.model_validate(result))
@@ -1105,9 +1122,15 @@ class AsyncCrud(Generic[ModelType]):
                 m2m_resolved = await cls._resolve_m2m(session, obj, only_set=True)
                 for rel_attr, related_instances in m2m_resolved.items():
                     setattr(db_model, rel_attr, related_instances)
-        await session.refresh(db_model)
+
+            pk_values: dict[str, Any] | None = None
             if cls.default_load_options:
-            db_model = await cls._reload_with_options(session, db_model)
+                await session.flush()
+                pk_values = cls._capture_pk_values(db_model)
+        if pk_values is not None:
+            db_model = await cls._reload_with_options_by_pk(session, pk_values)
+        else:
+            await session.refresh(db_model)
         if schema:
             return Response(data=schema.model_validate(db_model))
         return db_model

tests/conftest.py

@@ -476,3 +476,26 @@ async def db_session(engine):
         # Drop tables after test
         async with engine.begin() as conn:
             await conn.run_sync(Base.metadata.drop_all)
+
+
+@pytest.fixture(scope="function")
+async def db_session_expire_on_commit(engine):
+    """Session with expire_on_commit=True (the SQLAlchemy default).
+
+    Attributes read off an instance after commit are expired and trigger an
+    implicit (sync) refresh under this setting — which fails under asyncio
+    with MissingGreenlet. The other ``db_session`` fixture uses
+    ``expire_on_commit=False`` and would not catch that class of bug.
+    """
+    async with engine.begin() as conn:
+        await conn.run_sync(Base.metadata.create_all)
+
+    session_factory = async_sessionmaker(engine, expire_on_commit=True)
+    session = session_factory()
+
+    try:
+        yield session
+    finally:
+        await session.close()
+        async with engine.begin() as conn:
+            await conn.run_sync(Base.metadata.drop_all)

tests/test_crud.py

@@ -417,6 +417,55 @@ class TestDefaultLoadOptionsIntegration:
         assert updated.role is not None
         assert updated.role.name == "admin"
 
+    @pytest.mark.anyio
+    async def test_default_load_options_applied_to_create_expire_on_commit(
+        self, db_session_expire_on_commit: AsyncSession
+    ):
+        """create()'s reload uses captured PK values, not an expired instance attribute.
+
+        Regression test for MissingGreenlet: reading a PK off `db_model` after
+        commit under expire_on_commit=True (the SQLAlchemy default) would
+        trigger an implicit sync refresh, which fails under asyncio.
+        """
+        UserWithDefaultLoad = CrudFactory(
+            User, default_load_options=[selectinload(User.role)]
+        )
+        role = await RoleCrud.create(
+            db_session_expire_on_commit, RoleCreate(name="admin")
+        )
+        user = await UserWithDefaultLoad.create(
+            db_session_expire_on_commit,
+            UserCreate(username="alice", email="alice@test.com", role_id=role.id),
+        )
+        assert user.role is not None
+        assert user.role.name == "admin"
+
+    @pytest.mark.anyio
+    async def test_default_load_options_applied_to_update_expire_on_commit(
+        self, db_session_expire_on_commit: AsyncSession
+    ):
+        """update()'s reload uses captured PK values, not an expired instance attribute.
+
+        Regression test for MissingGreenlet under expire_on_commit=True.
+        """
+        UserWithDefaultLoad = CrudFactory(
+            User, default_load_options=[selectinload(User.role)]
+        )
+        role = await RoleCrud.create(
+            db_session_expire_on_commit, RoleCreate(name="admin")
+        )
+        user = await UserCrud.create(
+            db_session_expire_on_commit,
+            UserCreate(username="alice", email="alice@test.com"),
+        )
+        updated = await UserWithDefaultLoad.update(
+            db_session_expire_on_commit,
+            UserUpdate(role_id=role.id),
+            filters=[User.id == user.id],
+        )
+        assert updated.role is not None
+        assert updated.role.name == "admin"
+
     @pytest.mark.anyio
     async def test_load_options_overrides_default_load_options(
         self, db_session: AsyncSession