The DuckDB BigQuery extension defaults bq_query_timeout_ms to 90 s,
which is too tight for analyst-scale queries against view-backed BQ
datasets. Agnes already has apply_bq_session_settings() that bumps it
to 600 s (configurable via data_source.bigquery.query_timeout_ms), but
two regressions let the 90 s default leak through to live queries:
1. apply_bq_session_settings() swallowed every Exception silently. If
the BigQuery extension wasn't loaded on the connection yet, or the
installed extension version didn't recognise the setting, the SET
would fail and the function would return without surfacing the
problem. Operators saw 90 s timeouts on 'agnes query --remote' with
no log line explaining why.
2. The call sites in src/db.py:_reattach_remote_extensions and
src/orchestrator.py:_remote_attach only invoked
apply_bq_session_settings on the metadata-token branch (token_env
empty, the BqAccess contract). The token-based and no-auth branches
ran ATTACH against the BigQuery extension without ever applying the
timeout setting — so any BQ source registered with an explicit
token_env, or with no auth env at all, fell back to the 90 s default.
Fix:
- apply_bq_session_settings now logs WARNING on each failure path
(instance_config import error, non-numeric value, SET execution
failure, readback error). It also verifies the setting actually
landed via SELECT current_setting('bq_query_timeout_ms') and logs
WARNING when the readback disagrees with the requested value, which
catches the silent-ignore case some extension versions exhibit.
- Both _reattach_remote_extensions (src/db.py) and _remote_attach
(src/orchestrator.py) now call apply_bq_session_settings on every
branch that ATTACHes a BigQuery alias, not only the metadata-token
branch. Idempotent: calling it twice on the metadata-token path is a
no-op SET.
Tests:
- Extended the _RecordingConn fixture to support .fetchone() so the
readback assertion path works. Updated existing call-shape
assertions to expect the SELECT current_setting readback alongside
the SET. Added two new tests covering the WARNING surfaces for SET
failure and readback mismatch — regression guards for the silent-
fallback bug this PR addresses.
- Full BQ-touching suite (398 tests) passes.
32c8ea601a