Fix connection hang in database_is_empty() for SerenDB/Neon targets#24
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Reuse the existing target_client connection instead of creating a new connection when checking if a database is empty. This prevents connection pool exhaustion on serverless PostgreSQL providers (SerenDB, Neon) that have strict concurrent connection limits. The previous implementation would create a second connection while the first was still open, causing indefinite hangs when the connection pool was exhausted. Since tokio_postgres::connect has no built-in timeout, the operation would hang forever. Fixes #23
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Summary
initagainst SerenDB/Neon targets where the database already existstarget_clientconnection instead of creating a new connection indatabase_is_empty()Problem
When
database_is_empty()was called, it created a second database connection while the firsttarget_clientconnection was still active. SerenDB/Neon has strict concurrent connection limits, and sincetokio_postgres::connecthas no built-in timeout, the operation would hang indefinitely waiting for a connection slot.Reproduced on jobs:
438c3593-057c-45f3-9d23-6ddce6cea1bb314eacf8-5fcc-48d5-822a-3350f3b5a0e3Both hung for 6+ minutes at:
Solution
Changed
database_is_empty()to accept a&Clientreference instead of creating a new connection. The existingtarget_clientis already connected to the correct database and can be reused.Test plan
cargo buildpassescargo clippypassescargo testpasses (67 tests)Fixes #23