[elainewang-db]

Summary

#675 made agentbricks dev refuse to start when app.agentbricksdev.yaml already exists. Dev deletes that file on exit, but only in a finally block, which doesn't run when the process is stopped by SIGTERM (an IDE stop button, kill, docker stop). After one such stop, every later agentbricks dev on the project fails until the user deletes the file by hand:

error: Could not write .../app.agentbricksdev.yaml: it already exists.
  help: Inspect and remove the old local-only manifest before retrying.

The E2E dev suite (#706) hit this on its first restart of agentbricks dev.

The file name is specific to dev, and the file is always regenerated from app.yaml. So this restores the pre-#675 behavior of overwriting it. A failed write still removes the partial file, so apps run-local never picks up a half-written manifest.

Changes

• services/dev_service.py: _dev_entry_point writes the manifest with open("w") instead of open("x"), and removes the file if the write fails.
• tests/unit_tests/dev_service_test.py:
  • removes test_prepare_refuses_stale_manifest_without_clobbering_user_file, which asserted the refusal;
  • test_manifest_write_failure_removes_partial_manifest_and_stops_tracing now intercepts the "w" open mode.

Testing

• pytest tests/unit_tests: 1613 passed, 83 skipped.
• ruff check and ruff format --check pass. ty check reports nothing in the changed files.
• Not yet run live: the E2E test_dev[cli] in [l] [agentbricks] Add pytest E2E suites #706 should pass once this lands.

This pull request and its description were written by Isaac.

[jamesbxwu]

thanks for catching and fixing this!

The E2E dev suite (#706) hit this on its first restart of agentbricks dev.

Curious why this wasn't caught previously (perhaps I didn't run it fully?)

[elainewang-db]

thanks for catching and fixing this!

The E2E dev suite (#706) hit this on its first restart of agentbricks dev.

Curious why this wasn't caught previously (perhaps I didn't run it fully?)

ah I've actually rewritten the smoke tests, and was running that new version