Replace nc -z with pg_isready for PostgreSQL readiness check#305
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honteng wants to merge 1 commit intotemporalio:mainfrom
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Replace nc -z with pg_isready for PostgreSQL readiness check#305honteng wants to merge 1 commit intotemporalio:mainfrom
honteng wants to merge 1 commit intotemporalio:mainfrom
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nc -z only verifies that the TCP port is open, not that PostgreSQL is actually ready to accept queries. pg_isready is the official PostgreSQL utility that checks connection readiness (exit 0 = accepting connections, exit 1 = rejecting/still starting), providing a more reliable wait. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
nc -zwithpg_isreadyin thewait_for_postgres()function (docker/auto-setup.sh).nc -zonly checks whether the TCP port is open, which can return success before PostgreSQL is actually ready to accept queries (e.g., during crash recovery or startup).pg_isreadyis the official PostgreSQL client utility that performs a proper connection readiness check—it returns exit code 0 only when the server is accepting connections.postgresql-clientpackage to theauto-setupstage inserver.Dockerfileto makepg_isreadyavailable at runtime.Motivation
In environments where PostgreSQL takes time to initialize (large databases, slow storage, replicas catching up),
nc -zcan prematurely report the database as ready. This causestemporal-sql-toolschema setup commands to fail because the port is open but PostgreSQL is still in recovery. Usingpg_isreadyeliminates this race condition.Test plan
make build-native— confirm Docker images build successfully with the newpostgresql-clientpackagemake test— runs docker-compose integration test (PostgreSQL backend by default), confirming the readiness check works end-to-endpg_isreadycorrectly waits when PostgreSQL is slow to start (e.g., by delaying PostgreSQL startup in compose)🤖 Generated with Claude Code