refactor: simplify boomer runner

internal/boomer/boomer.go

@@ -91,7 +91,7 @@ func (b *Boomer) Run(tasks ...*Task) {
 	for _, o := range b.outputs {
 		b.localRunner.addOutput(o)
 	}
-	b.localRunner.run()
+	b.localRunner.start()
 }
 
 // RecordTransaction reports a transaction stat.
@@ -142,5 +142,5 @@ func (b *Boomer) Quit() {
 		log.Warn().Msg("boomer not initialized")
 		return
 	}
-	b.localRunner.close()
+	b.localRunner.stop()
 }

internal/boomer/runner.go

@@ -34,15 +34,9 @@ type runner struct {
 	rateLimitEnabled bool
 	stats            *requestStats
 
-	numClients int32
-	spawnRate  float64
-
-	// all running workers(goroutines) will select on this channel.
-	// close this channel will stop all running workers.
-	stopChan chan bool
-
-	// close this channel will stop all goroutines used in runner.
-	closeChan chan bool
+	currentClientsNum int32 // current clients count
+	spawnCount        int   // target clients to spawn
+	spawnRate         float64
 
 	outputs []Output
 }
@@ -116,16 +110,21 @@ func (r *runner) outputOnStop() {
 	wg.Wait()
 }
 
-func (r *runner) spawnWorkers(spawnCount int, quit chan bool, spawnCompleteFunc func()) {
-	log.Info().Int("spawnCount", spawnCount).Msg("Spawning clients immediately")
+func (r *runner) spawnWorkers(spawnCount int, spawnRate float64, quit chan bool, spawnCompleteFunc func()) {
+	log.Info().
+		Int("spawnCount", spawnCount).
+		Float64("spawnRate", spawnRate).
+		Msg("Spawning workers")
 
+	// TODO: spawn workers with spawnRate
 	for i := 1; i <= spawnCount; i++ {
 		select {
 		case <-quit:
 			// quit spawning goroutine
+			log.Info().Msg("Quitting spawning workers")
 			return
 		default:
-			atomic.AddInt32(&r.numClients, 1)
+			atomic.AddInt32(&r.currentClientsNum, 1)
 			go func() {
 				for {
 					select {
@@ -193,28 +192,11 @@ func (r *runner) getTask() *Task {
 	return nil
 }
 
-func (r *runner) startSpawning(spawnCount int, spawnRate float64, spawnCompleteFunc func()) {
-	r.stats.clearStatsChan <- true
-	r.stopChan = make(chan bool)
-
-	atomic.StoreInt32(&r.numClients, 0)
-
-	go r.spawnWorkers(spawnCount, r.stopChan, spawnCompleteFunc)
-}
-
-func (r *runner) stop() {
-	// stop previous goroutines without blocking
-	// those goroutines will exit when r.safeRun returns
-	close(r.stopChan)
-	if r.rateLimitEnabled {
-		r.rateLimiter.Stop()
-	}
-}
-
 type localRunner struct {
 	runner
 
-	spawnCount int
+	// close this channel will stop all goroutines used in runner.
+	stopChan chan bool
 }
 
 func newLocalRunner(tasks []*Task, rateLimiter RateLimiter, spawnCount int, spawnRate float64) (r *localRunner) {
@@ -222,7 +204,7 @@ func newLocalRunner(tasks []*Task, rateLimiter RateLimiter, spawnCount int, spaw
 	r.setTasks(tasks)
 	r.spawnRate = spawnRate
 	r.spawnCount = spawnCount
-	r.closeChan = make(chan bool)
+	r.stopChan = make(chan bool)
 
 	if rateLimiter != nil {
 		r.rateLimitEnabled = true
@@ -233,39 +215,55 @@ func newLocalRunner(tasks []*Task, rateLimiter RateLimiter, spawnCount int, spaw
 	return r
 }
 
-func (r *localRunner) run() {
+func (r *localRunner) start() {
+	// init state
 	r.state = stateInit
-	r.stats.start()
-	r.outputOnStart()
-
-	wg := sync.WaitGroup{}
-	wg.Add(1)
-	go func() {
-		for {
-			select {
-			case data := <-r.stats.messageToRunnerChan:
-				data["user_count"] = atomic.LoadInt32(&r.numClients)
-				r.outputOnEevent(data)
-			case <-r.closeChan:
-				r.stop()
-				wg.Done()
-				r.outputOnStop()
-				return
-			}
-		}
-	}()
+	atomic.StoreInt32(&r.currentClientsNum, 0)
+	r.stats.clearAll()
 
+	// start rate limiter
 	if r.rateLimitEnabled {
 		r.rateLimiter.Start()
 	}
-	r.startSpawning(r.spawnCount, r.spawnRate, nil)
 
-	wg.Wait()
-}
+	// all running workers(goroutines) will select on this channel.
+	// close this channel will stop all running workers.
+	quitChan := make(chan bool)
+	go r.spawnWorkers(r.spawnCount, r.spawnRate, quitChan, nil)
 
-func (r *localRunner) close() {
-	if r.stats != nil {
-		r.stats.close()
+	// output setup
+	r.outputOnStart()
+
+	// start running
+	var ticker = time.NewTicker(reportStatsInterval)
+	for {
+		select {
+		case t := <-r.stats.transactionChan:
+			r.stats.logTransaction(t.name, t.success, t.elapsedTime, t.contentSize)
+		case m := <-r.stats.requestSuccessChan:
+			r.stats.logRequest(m.requestType, m.name, m.responseTime, m.responseLength)
+		case n := <-r.stats.requestFailureChan:
+			r.stats.logRequest(n.requestType, n.name, n.responseTime, 0)
+			r.stats.logError(n.requestType, n.name, n.errMsg)
+		case <-ticker.C:
+			data := r.stats.collectReportData()
+			data["user_count"] = atomic.LoadInt32(&r.currentClientsNum)
+			r.outputOnEevent(data)
+		case <-r.stopChan:
+			// stop previous goroutines without blocking
+			// those goroutines will exit when r.safeRun returns
+			close(quitChan)
+			// stop rate limiter
+			if r.rateLimitEnabled {
+				r.rateLimiter.Stop()
+			}
+			// output teardown
+			r.outputOnStop()
+			return
+		}
 	}
-	close(r.closeChan)
+}
+
+func (r *localRunner) stop() {
+	close(r.stopChan)
 }

internal/boomer/runner_test.go

@@ -85,7 +85,7 @@ func TestLocalRunner(t *testing.T) {
 	}
 	tasks := []*Task{taskA}
 	runner := newLocalRunner(tasks, nil, 2, 2)
-	go runner.run()
+	go runner.start()
 	time.Sleep(4 * time.Second)
-	runner.close()
+	runner.stop()
 }

internal/boomer/stats.go

@@ -36,11 +36,8 @@ type requestStats struct {
 	transactionPassed int64 // accumulated number of passed transactions
 	transactionFailed int64 // accumulated number of failed transactions
 
-	requestSuccessChan  chan *requestSuccess
-	requestFailureChan  chan *requestFailure
-	clearStatsChan      chan bool
-	messageToRunnerChan chan map[string]interface{}
-	shutdownChan        chan bool
+	requestSuccessChan chan *requestSuccess
+	requestFailureChan chan *requestFailure
 }
 
 func newRequestStats() (stats *requestStats) {
@@ -54,9 +51,6 @@ func newRequestStats() (stats *requestStats) {
 	stats.transactionChan = make(chan *transaction, 100)
 	stats.requestSuccessChan = make(chan *requestSuccess, 100)
 	stats.requestFailureChan = make(chan *requestFailure, 100)
-	stats.clearStatsChan = make(chan bool)
-	stats.messageToRunnerChan = make(chan map[string]interface{}, 10)
-	stats.shutdownChan = make(chan bool)
 
 	stats.total = &statsEntry{
 		Name:   "Total",
@@ -106,9 +100,9 @@ func (s *requestStats) get(name string, method string) (entry *statsEntry) {
 			Name:          name,
 			Method:        method,
 			NumReqsPerSec: make(map[int64]int64),
+			NumFailPerSec: make(map[int64]int64),
 			ResponseTimes: make(map[int64]int64),
 		}
-		newEntry.reset()
 		s.entries[name+method] = newEntry
 		return newEntry
 	}
@@ -155,36 +149,6 @@ func (s *requestStats) collectReportData() map[string]interface{} {
 	return data
 }
 
-func (s *requestStats) start() {
-	go func() {
-		var ticker = time.NewTicker(reportStatsInterval)
-		for {
-			select {
-			case t := <-s.transactionChan:
-				s.logTransaction(t.name, t.success, t.elapsedTime, t.contentSize)
-			case m := <-s.requestSuccessChan:
-				s.logRequest(m.requestType, m.name, m.responseTime, m.responseLength)
-			case n := <-s.requestFailureChan:
-				s.logRequest(n.requestType, n.name, n.responseTime, 0)
-				s.logError(n.requestType, n.name, n.errMsg)
-			case <-s.clearStatsChan:
-				s.clearAll()
-			case <-ticker.C:
-				data := s.collectReportData()
-				// send data to channel, no network IO in this goroutine
-				s.messageToRunnerChan <- data
-			case <-s.shutdownChan:
-				return
-			}
-		}
-	}()
-}
-
-// close is used by unit tests to avoid leakage of goroutines
-func (s *requestStats) close() {
-	close(s.shutdownChan)
-}
-
 // statsEntry represents a single stats entry (name and method)
 type statsEntry struct {
 	// Name (URL) of this stats entry

internal/boomer/stats_test.go

@@ -2,7 +2,6 @@ package boomer
 
 import (
 	"testing"
-	"time"
 )
 
 func TestLogRequest(t *testing.T) {
@@ -135,10 +134,8 @@ func TestClearAll(t *testing.T) {
 
 func TestClearAllByChannel(t *testing.T) {
 	newStats := newRequestStats()
-	newStats.start()
-	defer newStats.close()
 	newStats.logRequest("http", "success", 1, 20)
-	newStats.clearStatsChan <- true
+	newStats.clearAll()
 
 	if newStats.total.NumRequests != 0 {
 		t.Error("After clearAll(), newStats.total.numRequests is wrong, expected: 0, got:", newStats.total.NumRequests)
@@ -217,34 +214,3 @@ func TestCollectReportData(t *testing.T) {
 		t.Error("Key stats not found")
 	}
 }
-
-func TestStatsStart(t *testing.T) {
-	newStats := newRequestStats()
-	newStats.start()
-	defer newStats.close()
-
-	newStats.requestSuccessChan <- &requestSuccess{
-		requestType:    "http",
-		name:           "success",
-		responseTime:   2,
-		responseLength: 30,
-	}
-
-	newStats.requestFailureChan <- &requestFailure{
-		requestType:  "http",
-		name:         "failure",
-		responseTime: 1,
-		errMsg:       "500 error",
-	}
-
-	var ticker = time.NewTicker(reportStatsInterval + 500*time.Millisecond)
-	for {
-		select {
-		case <-ticker.C:
-			t.Error("Timeout waiting for stats reports to runner")
-		case <-newStats.messageToRunnerChan:
-			goto end
-		}
-	}
-end:
-}