fix(cache): await db query before cache.onMutate to close stale-repopulation race#5951
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fix(cache): await db query before cache.onMutate to close stale-repopulation race#5951sanjibani wants to merge 1 commit into
sanjibani wants to merge 1 commit into
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…ulation race The cache invalidation in PgPreparedQuery.queryWithCache was firing concurrently with the DB write via Promise.all, contradicting the in-code comment that said the DB write should resolve first. When onMutate (a single Redis Lua script call) completed before the DB write committed, a concurrent SELECT could read the pre-mutation row and repopulate the cache via cache.put(), serving stale data until TTL expiry. Repro: write-heavy workload with cache ex > DB RTT. Change Promise.all([query(), onMutate]) to sequential await. The DB write now commits before any cache keys are cleared, closing the race. Same fix applied to mysql-core, sqlite-core, gel-core, singlestore-core which shared the identical pattern. Regression test added in pg-common-cache.ts that fails on the old ordering (query:end > onMutate) and passes on the new (query:end < onMutate). Closes drizzle-team#5828
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Closes #5828.
The cache invalidation in
PgPreparedQuery.queryWithCachewas firing concurrently with the DB write viaPromise.all, contradicting the in-code comment that said the DB write should resolve first.When
onMutate(a single Redis Lua script call) completed before the DB write committed, a concurrent SELECT could read the pre-mutation row and repopulate the cache viacache.put(), serving stale data until TTL expiry. Repro: write-heavy workload withcache.exlarger than the DB RTT.Change
Promise.all([query(), onMutate])to sequentialawait. The DB write now commits before any cache keys are cleared, closing the race. Same fix applied to mysql-core, sqlite-core, gel-core, singlestore-core which shared the identical pattern.Regression test added in pg-common-cache.ts that fails on the old ordering and passes on the new.