Avoid leaking connections if _can_use_connection fails #1269
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elprans approved these changes Oct 11, 2025
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If _can_use_connection fails (say, because of an asyncio timeout), then we may have a full connection that has been created but would be leaked by this function. (note:
_connect_addrtakes care of cleaning up after itself if it fails partway)This is particularly possible in the case of pgbouncer, where we may succeed at establishing a connection much quicker than even a trivial call to the backing database would take.
I believe this failure mode was introduced in #987
I'm not certain if we should
awaithere or just punt the closing of the other connections to a background task (I don't know how riskycloseis on an established connection).