fix(db): release read transactions — no more idle-in-transaction on Postgres - #8
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…ostgres With autocommit=False every SELECT opened a transaction that nothing ended, so pooled request threads and the chat websocket idled inside transactions, pinning ACCESS SHARE locks. Lock-safe plugin migrations (ALTER TABLE) then timed out on every boot in production, columns were never added, and saves silently dropped fields for the missing columns (200 OK, edits lost). _PgConn now tracks pending writes and rolls back right after a read when no write is uncommitted and no explicit transaction (submit/cancel) is active. psycopg's client-side cursor has already buffered the rows, so fetching after the release works. Write flows and their atomicity are byte-for-byte unchanged. tests/test_txn_release.py covers the semantics plus the real failure mode: a quiet reader thread + ensure_column now succeeds. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
…key/value Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Fixes the production migration-starvation bug: with
autocommit=Falseevery SELECT opened a transaction that nothing ended, so pooled request threads (and the chat websocket) idled inside transactions holdingACCESS SHARElocks. The lock-safe plugin migrations'ALTER TABLEthen hit its lock timeout on every boot (observed on erp.lambda.dev: internal migrations 0005/0006/0008/0009 failing since 0.6.3), columns were never created, and_persist()silently dropped edits to those fields — saves returned 200 OK but nothing stuck.Fix:
_PgConntracks pending writes and rolls back immediately after a read when no write is uncommitted and no explicit transaction (submit/cancel) is active. psycopg's client-side cursor already buffered the result set, so post-release fetching works. Write flows and atomicity unchanged; SQLite untouched.Test:
tests/test_txn_release.py(Postgres CI) — read releases, helpers release, interleaved reads don't roll back pending writes, explicit-transaction reads keep their snapshot, and the real failure mode: a quiet reader thread +ensure_columnsucceeds.🤖 Generated with Claude Code