Function Example_jobCancelFromClient

example_job_cancel_from_client_test.go:41–101

Example_jobCancelFromClient demonstrates how to permanently cancel a job from any Client using JobCancel.

()

// Example_jobCancelFromClient demonstrates how to permanently cancel a job from
// any Client using JobCancel.
func Example_jobCancelFromClient() {
	ctx := context.Background()

	dbPool, err := pgxpool.New(ctx, riversharedtest.TestDatabaseURL())
	if err != nil {
		panic(err)
	}
	defer dbPool.Close()

	jobChan := make(chan int64)

	workers := river.NewWorkers()
	river.AddWorker(workers, &SleepingWorker{jobChan: jobChan})

	riverClient, err := river.NewClient(riverpgxv5.New(dbPool), initTestConfig(ctx, dbPool, &river.Config{
		Logger: slog.New(slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{Level: slog.LevelWarn, ReplaceAttr: slogutil.NoLevelTimeJobID})),
		Queues: map[string]river.QueueConfig{
			river.QueueDefault: {MaxWorkers: 10},
		},
		Workers: workers,
	}))
	if err != nil {
		panic(err)
	}

	// Not strictly needed, but used to help this test wait until job is worked.
	subscribeChan, subscribeCancel := riverClient.Subscribe(river.EventKindJobCancelled)
	defer subscribeCancel()

	if err := riverClient.Start(ctx); err != nil {
		panic(err)
	}
	insertRes, err := riverClient.Insert(ctx, CancellingArgs{ShouldCancel: true}, nil)
	if err != nil {
		panic(err)
	}
	select {
	case <-jobChan:
	case <-time.After(2 * time.Second):
		panic("no jobChan signal received")
	}

	// There is presently no way to wait for the client to be 100% ready, so we
	// sleep for a bit to give it time to start up. This is only needed in this
	// example because we need the notifier to be ready for it to receive the
	// cancellation signal.
	time.Sleep(500 * time.Millisecond)

	if _, err = riverClient.JobCancel(ctx, insertRes.Job.ID); err != nil {
		panic(err)
	}
	// Wait for jobs to complete. Only needed for purposes of the example test.
	riversharedtest.WaitOrTimeoutN(testutil.PanicTB(), subscribeChan, 1)

	if err := riverClient.Stop(ctx); err != nil {
		panic(err)
	}