snapshot of https://github.com/ThreeDotsLabs/watermill.git (master, 2026-09-15; blobs > 131072B omitted)

_examples/pubsubs/googlecloud/main.go

@@ -0,0 +1,69 @@
+// Sources for https://watermill.io/learn/getting-started/
+package main
+
+import (
+	"context"
+	"log"
+	"time"
+
+	"github.com/ThreeDotsLabs/watermill"
+	"github.com/ThreeDotsLabs/watermill-googlecloud/v2/pkg/googlecloud"
+	"github.com/ThreeDotsLabs/watermill/message"
+)
+
+func main() {
+	logger := watermill.NewStdLogger(false, false)
+	subscriber, err := googlecloud.NewSubscriber(
+		googlecloud.SubscriberConfig{
+			// custom function to generate Subscription Name,
+			// there are also predefined TopicSubscriptionName and TopicSubscriptionNameWithSuffix available.
+			GenerateSubscriptionName: func(topic string) string {
+				return "test-sub_" + topic
+			},
+			ProjectID: "test-project",
+		},
+		logger,
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	// Subscribe will create the subscription. Only messages that are sent after the subscription is created may be received.
+	messages, err := subscriber.Subscribe(context.Background(), "example.topic")
+	if err != nil {
+		panic(err)
+	}
+
+	go process(messages)
+
+	publisher, err := googlecloud.NewPublisher(googlecloud.PublisherConfig{
+		ProjectID: "test-project",
+	}, logger)
+	if err != nil {
+		panic(err)
+	}
+
+	publishMessages(publisher)
+}
+
+func publishMessages(publisher message.Publisher) {
+	for {
+		msg := message.NewMessage(watermill.NewUUID(), []byte("Hello, world!"))
+
+		if err := publisher.Publish("example.topic", msg); err != nil {
+			panic(err)
+		}
+
+		time.Sleep(time.Second)
+	}
+}
+
+func process(messages <-chan *message.Message) {
+	for msg := range messages {
+		log.Printf("received message: %s, payload: %s", msg.UUID, string(msg.Payload))
+
+		// we need to Acknowledge that we received and processed the message,
+		// otherwise, it will be resent over and over again.
+		msg.Ack()
+	}
+}