fix(message-db): reconnect stale pooled connections dropped by the se…#3603
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kiku98 wants to merge 1 commit into
Open
fix(message-db): reconnect stale pooled connections dropped by the se…#3603kiku98 wants to merge 1 commit into
kiku98 wants to merge 1 commit into
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…rver Pooled Mysql2::Client connections were handed out without verifying they were still alive. A connection parked in the pool during a quiet period could be closed server-side once it idled past `wait_timeout`, and the next query on it raised "disconnected by the server because of inactivity". This error was not matched by the pool's reconnect guard, so it propagated up, aborted message processing and left queued messages stuck. - Ping each pooled connection on checkout; discard and replace it if the server has already closed it. - Broaden the dead-connection pattern to also match the inactivity / server-disconnect wording as defence-in-depth for connections that die mid-block.
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Problem
The MessageDB connection pool hands out pooled Mysql2::Client connections without checking they're still alive. A connection parked in the pool during a quiet period is closed server-side once it idles past MySQL's wait_timeout; the next query on it raises Mysql2::Error: The client was disconnected by the server because of inactivity. The pool's reconnect guard only matched /(lost connection|gone away|not connected)/i, so this error was re-raised instead of triggering a reconnect — aborting message processing and leaving queued messages stuck.
Fix
Ping each pooled connection on checkout; discard and replace it if the server has already closed it.
Broaden the dead-connection pattern to also match the inactivity / server-disconnect wording, as defence-in-depth for connections that die mid-block.