fix: PoolClient leak after an error in PostgresDriver

[drauggres]

After an error, the PoolClient was not released. This was causing the broken connection to be reused. When multiple servers were specified in the connection string, leaked PoolClient prevented connection to another server.

Pull-Request Checklist

• Code is up-to-date with the master branch
• npm run format to apply prettier formatting
• npm run test passes with this change
• This pull request links relevant issues as Fixes #0000 (N/A)
• There are new or updated unit tests validating the change (N/A)
• Documentation has been updated to reflect this change (N/A)
• The new commits follow conventions explained in CONTRIBUTING.md

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Summary by cubic

Fixes a connection leak in PostgresDriver by releasing the PoolClient on connection errors. This prevents reusing broken connections and restores failover when multiple hosts are in the connection string.

• Bug Fixes
  • Release PoolClient on "error" and log a warning.
  • Remove "error" and "release" listeners after client release.

^{Written for commit 40ab31f. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 1 file

Prompt for AI agents (all issues)

Check if these issues are valid — if so, understand the root cause of each and fix them.


<file name="src/driver/postgres/PostgresDriver.ts">

<violation number="1" location="src/driver/postgres/PostgresDriver.ts:1200">
P1: Connection and listener leak when initialization queries throw: connection is never released and attached listeners stay registered.</violation>
</file>

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[cubic-dev-ai]

P1: Connection and listener leak when initialization queries throw: connection is never released and attached listeners stay registered.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At src/driver/postgres/PostgresDriver.ts, line 1200:

<comment>Connection and listener leak when initialization queries throw: connection is never released and attached listeners stay registered.</comment>

<file context>
@@ -1180,6 +1180,24 @@ export class PostgresDriver implements Driver {
+            }
+        }
+        connection.on("error", onError)
+        master.on("release", onRelease)
         const { schema } = this.options
         if (schema && schema !== "public") {
</file context>

[drauggres]

Released here:
https://github.com/n8n-io/typeorm/pull/45/changes#diff-3346a7798b4db06d6debd87138bb8322626b91c1c325b730d51ee3afc1b4c2bbR1195-R1196