chore: ensure pubsub messages are delivered in order for in-memory variant (#6474)

kylecarbs · web-flow · commit fd02f73708e5 · 2023-03-07T04:36:25.000Z
PostgreSQL provides this guarantee, which led to some flakes in tests. See: https://github.com/coder/coder/actions/runs/4350034299/jobs/7600478096
diff --git a/coderd/database/pubsub_memory.go b/coderd/database/pubsub_memory.go
@@ -46,9 +46,16 @@ func (m *memoryPubsub) Publish(event string, message []byte) error {
 	if !ok {
 		return nil
 	}
+	var wg sync.WaitGroup
 	for _, listener := range listeners {
-		go listener(context.Background(), message)
+		wg.Add(1)
+		listener := listener
+		go func() {
+			defer wg.Done()
+			listener(context.Background(), message)
+		}()
 	}
+	wg.Wait()
 
 	return nil
 }

Original file line number	Diff line number	Diff line change
`@@ -46,9 +46,16 @@ func (m *memoryPubsub) Publish(event string, message []byte) error {`
`46`	`46`	`if !ok {`
`47`	`47`	`return nil`
`48`	`48`	`}`
	`49`	`+ var wg sync.WaitGroup`
`49`	`50`	`for _, listener := range listeners {`
`50`		`- go listener(context.Background(), message)`
	`51`	`+ wg.Add(1)`
	`52`	`+ listener := listener`
	`53`	`+ go func() {`
	`54`	`+ defer wg.Done()`
	`55`	`+ listener(context.Background(), message)`
	`56`	`+ }()`
`51`	`57`	`}`
	`58`	`+ wg.Wait()`
`52`	`59`
`53`	`60`	`return nil`
`54`	`61`	`}`