Harden integration tests against the post-boot Moodle login race#74
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The Docker-backed integration suite intermittently failed at fixture setup with 'Moodle login failed: invalid username or password', on whichever test a pytest-xdist worker ran first. This is a transient race: right after a freshly-started Moodle container begins serving its login page, the very first login attempt sometimes fails while Moodle finishes initializing caches/sessions; a moment later the same credentials work (which is why reruns always went green). Add a session-scoped, autouse warmup fixture that performs a retrying login (up to 6 attempts, 5s apart) once per session -- i.e. once per xdist worker -- before any integration test runs. A successful warmup means the Moodle server is warm, so every subsequent per-test (new-session) login is reliable. It is a no-op unless --integration is passed, so unit runs are unaffected. No library/CLI change; this only touches the integration test harness.
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Summary
Eliminates the recurring integration-test flake where fixture setup fails with
Moodle login failed: invalid username or password. Adds a session-scoped, autouse login warmup (retry) fixture so a freshly-booted Moodle is warm before any test logs in. Integration-harness only; no library/CLI change.Problem
Right after a fresh Moodle container starts serving
/login/index.php, the first login attempt intermittently fails with "invalid username or password" while Moodle finishes initializing (caches/sessions); a moment later the same credentials work — which is exactly why every occurrence went green on rerun. Underpytest-xdist -n autothis hit whichever test a worker ran first (observed ontest_create_and_delete_course,test_add_assign,test_list_courses, …), making the whole suite flaky and forcing repeated CI reruns.Fix
A
scope="session", autouse=Truefixture (_warm_up_moodle_login) intests/conftest.pythat, only when--integrationis active, performs a retrying warmup login (up to 6 attempts, 5s apart) once per session — i.e. once per xdist worker — before tests run. Once the warmup login succeeds the Moodle server is warm, so every subsequent per-test (new-session) login is reliable. If login never succeeds within the budget itpytest.exits with a clear message (a genuinely-down Moodle still fails fast-ish, not silently).Test plan
pytest tests/unit— green; the warmup fixture is a no-op without--integration, so unit runs are unaffected.make lint(black/isort/flake8) — clean.Backwards compatibility
No change to any library or CLI behavior; only the integration test harness. Unit tests, and any environment without
--integration, are unaffected.Notes for reviewers
This is the counterpart to #62 (which serialized course creation across workers) and #73 (ephemeral CI containers + boot diagnostics): together they target the main sources of integration flakiness. The warmup absorbs the login race specifically. Retry budget (6×5s) is generous but only spends time when the race is actually occurring — a first-try success is instant.