func delete(client *pubsub.Client, name string) error {
	ctx := context.Background()
	// [START delete_subscription]
	sub := client.Subscription(name)
	if err := sub.Delete(ctx); err != nil {
		return err
	}
	fmt.Println("Subscription deleted.")
	// [END delete_subscription]
	return nil
}
func getPolicy(c *pubsub.Client, subName string) *iam.Policy {
	ctx := context.Background()

	// [START pubsub_get_subscription_policy]
	policy, err := c.Subscription(subName).IAM().Policy(ctx)
	if err != nil {
		log.Fatal(err)
	}
	for _, role := range policy.Roles() {
		log.Printf("%q: %q", role, policy.Members(role))
	}
	// [END pubsub_get_subscription_policy]
	return policy
}
func testPermissions(c *pubsub.Client, subName string) []string {
	ctx := context.Background()

	// [START pubsub_test_subscription_permissions]
	sub := c.Subscription(subName)
	perms, err := sub.IAM().TestPermissions(ctx, []string{
		"pubsub.subscriptions.consume",
		"pubsub.subscriptions.update",
	})
	if err != nil {
		log.Fatal(err)
	}
	for _, perm := range perms {
		log.Printf("Allowed: %v", perm)
	}
	// [END pubsub_test_subscription_permissions]
	return perms
}
func addUsers(c *pubsub.Client, subName string) {
	ctx := context.Background()

	// [START pubsub_set_subscription_policy]
	sub := c.Subscription(subName)
	policy, err := sub.IAM().Policy(ctx)
	if err != nil {
		log.Fatalf("GetPolicy: %v", err)
	}
	// Other valid prefixes are "serviceAccount:", "user:"
	// See the documentation for more values.
	policy.Add(iam.AllUsers, iam.Viewer)
	policy.Add("group:[email protected]", iam.Editor)
	if err := sub.IAM().SetPolicy(ctx, policy); err != nil {
		log.Fatalf("SetUser: %v", err)
	}
	// NOTE: It may be necessary to retry this operation if IAM policies are
	// being modified concurrently. SetPolicy will return an error if the policy
	// was modified since it was retrieved.
	// [END pubsub_set_subscription_policy]
}
func pullMsgs(client *pubsub.Client, name string, topic *pubsub.Topic) error {
	ctx := context.Background()

	// publish 10 messages on the topic.
	for i := 0; i < 10; i++ {
		_, err := topic.Publish(ctx, &pubsub.Message{
			Data: []byte(fmt.Sprintf("hello world #%d", i)),
		})
		if err != nil {
			return err
		}
	}

	// [START pull_messages]
	sub := client.Subscription(name)
	it, err := sub.Pull(ctx)
	if err != nil {
		return err
	}
	defer it.Stop()

	// Consume 10 messages.
	for i := 0; i < 10; i++ {
		msg, err := it.Next()
		if err == iterator.Done {
			break
		}
		if err != nil {
			return err
		}
		fmt.Printf("Got message: %q\n", string(msg.Data))
		msg.Done(true)
	}
	// [END pull_messages]
	return nil
}