feat(queue): auto scale the task worker (#44)

consumer.go

@@ -101,26 +101,25 @@ func (s *Consumer) handle(job Job) error {
 }
 
 // Run start the worker
-func (s *Consumer) Run() error {
+func (s *Consumer) Run(task QueuedMessage) error {
 	// check queue status
 	select {
 	case <-s.stop:
 		return ErrQueueShutdown
 	default:
 	}
 
-	for task := range s.taskQueue {
-		var data Job
-		_ = json.Unmarshal(task.Bytes(), &data)
-		if v, ok := task.(Job); ok {
-			if v.Task != nil {
-				data.Task = v.Task
-			}
-		}
-		if err := s.handle(data); err != nil {
-			s.logger.Error(err.Error())
+	var data Job
+	_ = json.Unmarshal(task.Bytes(), &data)
+	if v, ok := task.(Job); ok {
+		if v.Task != nil {
+			data.Task = v.Task
 		}
 	}
+	if err := s.handle(data); err != nil {
+		return err
+	}
+
 	return nil
 }
 
@@ -148,19 +147,28 @@ func (s *Consumer) Usage() int {
 }
 
 // Queue send notification to queue
-func (s *Consumer) Queue(job QueuedMessage) error {
+func (s *Consumer) Queue(task QueuedMessage) error {
 	if atomic.LoadInt32(&s.stopFlag) == 1 {
 		return ErrQueueShutdown
 	}
 
 	select {
-	case s.taskQueue <- job:
+	case s.taskQueue <- task:
 		return nil
 	default:
 		return errMaxCapacity
 	}
 }
 
+func (s *Consumer) Request() (QueuedMessage, error) {
+	select {
+	case task := <-s.taskQueue:
+		return task, nil
+	default:
+		return nil, errors.New("no message in queue")
+	}
+}
+
 // NewConsumer for struc
 func NewConsumer(opts ...Option) *Consumer {
 	o := NewOptions(opts...)

consumer_test.go

@@ -50,14 +50,16 @@ func TestCustomFuncAndWait(t *testing.T) {
 	q, err := NewQueue(
 		WithWorker(w),
 		WithWorkerCount(2),
+		WithLogger(NewLogger()),
 	)
 	assert.NoError(t, err)
-	q.Start()
-	time.Sleep(100 * time.Millisecond)
 	assert.NoError(t, q.Queue(m))
 	assert.NoError(t, q.Queue(m))
 	assert.NoError(t, q.Queue(m))
 	assert.NoError(t, q.Queue(m))
+	q.Start()
+	time.Sleep(100 * time.Millisecond)
+	assert.Equal(t, 2, int(q.metric.BusyWorkers()))
 	time.Sleep(600 * time.Millisecond)
 	q.Shutdown()
 	q.Wait()
@@ -84,26 +86,6 @@ func TestEnqueueJobAfterShutdown(t *testing.T) {
 	q.Wait()
 }
 
-func TestConsumerNumAfterShutdown(t *testing.T) {
-	w := NewConsumer()
-	q, err := NewQueue(
-		WithWorker(w),
-		WithWorkerCount(2),
-	)
-	assert.NoError(t, err)
-	q.Start()
-	q.Start()
-	time.Sleep(50 * time.Millisecond)
-	assert.Equal(t, 4, q.Workers())
-	q.Shutdown()
-	q.Wait()
-	assert.Equal(t, 0, q.Workers())
-	// show queue has been shutdown meesgae
-	q.Start()
-	q.Start()
-	assert.Equal(t, 0, q.Workers())
-}
-
 func TestJobReachTimeout(t *testing.T) {
 	m := mockMessage{
 		message: "foo",
@@ -131,12 +113,10 @@ func TestJobReachTimeout(t *testing.T) {
 		WithWorkerCount(2),
 	)
 	assert.NoError(t, err)
-	q.Start()
-	time.Sleep(50 * time.Millisecond)
 	assert.NoError(t, q.QueueWithTimeout(30*time.Millisecond, m))
+	q.Start()
 	time.Sleep(50 * time.Millisecond)
-	q.Shutdown()
-	q.Wait()
+	q.Release()
 }
 
 func TestCancelJobAfterShutdown(t *testing.T) {
@@ -167,17 +147,15 @@ func TestCancelJobAfterShutdown(t *testing.T) {
 		WithWorkerCount(2),
 	)
 	assert.NoError(t, err)
-	q.Start()
-	time.Sleep(50 * time.Millisecond)
 	assert.NoError(t, q.QueueWithTimeout(100*time.Millisecond, m))
-	q.Shutdown()
-	q.Wait()
+	assert.NoError(t, q.QueueWithTimeout(100*time.Millisecond, m))
+	q.Start()
+	time.Sleep(10 * time.Millisecond)
+	assert.Equal(t, 2, int(q.metric.busyWorkers))
+	q.Release()
 }
 
 func TestGoroutineLeak(t *testing.T) {
-	m := mockMessage{
-		message: "foo",
-	}
 	w := NewConsumer(
 		WithLogger(NewEmptyLogger()),
 		WithFn(func(ctx context.Context, m QueuedMessage) error {
@@ -200,20 +178,22 @@ func TestGoroutineLeak(t *testing.T) {
 		}),
 	)
 	q, err := NewQueue(
-		WithLogger(NewEmptyLogger()),
+		WithLogger(NewLogger()),
 		WithWorker(w),
 		WithWorkerCount(10),
 	)
 	assert.NoError(t, err)
-	q.Start()
-	time.Sleep(50 * time.Millisecond)
-	for i := 0; i < 500; i++ {
-		m.message = fmt.Sprintf("foobar: %d", i+1)
+	for i := 0; i < 400; i++ {
+		m := mockMessage{
+			message: fmt.Sprintf("new message: %d", i+1),
+		}
+
 		assert.NoError(t, q.Queue(m))
 	}
+
+	q.Start()
 	time.Sleep(2 * time.Second)
-	q.Shutdown()
-	q.Wait()
+	q.Release()
 	fmt.Println("number of goroutines:", runtime.NumGoroutine())
 }
 
@@ -231,12 +211,10 @@ func TestGoroutinePanic(t *testing.T) {
 		WithWorkerCount(2),
 	)
 	assert.NoError(t, err)
-	q.Start()
-	time.Sleep(50 * time.Millisecond)
 	assert.NoError(t, q.Queue(m))
-	time.Sleep(50 * time.Millisecond)
-	q.Shutdown()
-	q.Wait()
+	q.Start()
+	time.Sleep(10 * time.Millisecond)
+	q.Release()
 }
 
 func TestHandleTimeout(t *testing.T) {

pool_test.go

@@ -3,7 +3,6 @@ package queue
 import (
 	"context"
 	"testing"
-	"time"
 
 	"github.com/stretchr/testify/assert"
 )
@@ -14,9 +13,6 @@ func TestNewPoolWithQueueTask(t *testing.T) {
 	rets := make(chan struct{}, taskN)
 
 	p := NewPool(totalN)
-	time.Sleep(time.Millisecond * 50)
-	assert.Equal(t, totalN, p.Workers())
-
 	for i := 0; i < taskN; i++ {
 		assert.NoError(t, p.QueueTask(func(context.Context) error {
 			rets <- struct{}{}
@@ -30,5 +26,5 @@ func TestNewPoolWithQueueTask(t *testing.T) {
 
 	// shutdown all, and now running worker is 0
 	p.Release()
-	assert.Equal(t, 0, p.Workers())
+	assert.Equal(t, 0, p.BusyWorkers())
 }