Authenticated client — existing test
This test verifies that an authorized client can fetch all posts:authorized_clientis expected to include authentication credentials (e.g., a JWT).test_postsis a fixture that creates posts in the test database before the request runs.- The
validatehelper ensures each returned post can be parsed into thePostOutPydantic schema, which will raise an error if the response shape is wrong.
res.json() returned a different number of posts than test_posts. Possible causes include:
- The API filters posts by owner, returning only posts belonging to the authorized user rather than all test posts.
- The
test_postsfixture created posts under different users or contexts. - There is an ordering or creation timing issue in setup causing fewer posts to exist at request time.
- Print
res.json()during the test run to inspect the exact returned payload. - Verify how
test_postsassigns ownership to posts and thatauthorized_clientcorresponds to the same user. - Ensure database cleanup/fixtures are running deterministically; check for shared state between tests.
Make the request without authentication to verify unauthorized behaviour. The test fixtures will create posts (and any necessary test users) before the request runs, so you don’t need to create a user manually.
Unauthorized user — new test
Add a test that confirms unauthenticated users receive401 Unauthorized when requesting the posts list:
/posts/ endpoint. The client fixture performs requests without any authentication headers.
Test summary
Additional recommendations
- Use debug prints (or
pytest -k test_name -s) to inspectres.json()during development. - If authorization is user-scoped, assert that the number of returned posts equals the posts owned by the authorized user (not necessarily
len(test_posts)). - Validate the response schema by mapping results to
schemas.PostOut(as shown) to detect shape mismatches early.
Links and references
- FastAPI Security: https://fastapi.tiangolo.com/tutorial/security/
- PyTest fixtures: https://docs.pytest.org/en/stable/fixture.html
- Pydantic models: https://pydantic-docs.helpmanual.io/