Improve shutdown sequence

main.go

@@ -191,12 +191,8 @@ func main() {
 	server := &http.Server{Addr: listenAddr}
 
 	// Run the producer
-	go func() {
-		if err := server.ListenAndServe(); err != nil &&
-			err != http.ErrServerClosed {
-			log.Fatalln(err)
-		}
-	}()
+	errs := make(chan error, 1)
+	go func() { errs <- server.ListenAndServe() }()
 
 	// Run the consumer
 	ctx, ctxCancel := context.WithCancel(context.Background())
@@ -217,7 +213,12 @@ func main() {
 	// Wait for a termination signal
 	sigs := make(chan os.Signal, 1)
 	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
-	<-sigs
+
+	select {
+	case <-sigs:
+	case err := <-errs:
+		log.Println(err)
+	}
 
 	// Stop the producer gracefully
 	ctxSd, ctxSdCancel := context.WithTimeout(context.Background(), 5)