fix: close pg PubSub listener to avoid race

spikecurtis · spikecurtis · commit 0db909c36c6c · 2024-01-16T16:49:39.000+04:00
diff --git a/coderd/database/pubsub/pubsub.go b/coderd/database/pubsub/pubsub.go
@@ -239,8 +239,11 @@ func (p *pgPubsub) Publish(event string, message []byte) error {
 
 // Close closes the pubsub instance.
 func (p *pgPubsub) Close() error {
-	p.cancel()
+	// canceling the context also causes the listener to be closed, so directly
+	// close it before canceling the context to avoid the race. If we lost the
+	// race we'd return an error about the listener already being closed.
 	err := p.pgListener.Close()
+	p.cancel()
 	<-p.listenDone
 	return err
 }
