Add load tester flag to log the cmd output

cmd/loadtester/main.go

@@ -9,16 +9,19 @@ import (
 	"time"
 )
 
+var VERSION = "0.0.2"
 var (
-	logLevel string
-	port     string
-	timeout  time.Duration
+	logLevel     string
+	port         string
+	timeout      time.Duration
+	logCmdOutput bool
 )
 
 func init() {
 	flag.StringVar(&logLevel, "log-level", "debug", "Log level can be: debug, info, warning, error.")
 	flag.StringVar(&port, "port", "9090", "Port to listen on.")
 	flag.DurationVar(&timeout, "timeout", time.Hour, "Command exec timeout.")
+	flag.BoolVar(&logCmdOutput, "log-cmd-output", true, "Log command output to stderr")
 }
 
 func main() {
@@ -32,10 +35,10 @@ func main() {
 
 	stopCh := signals.SetupSignalHandler()
 
-	taskRunner := loadtester.NewTaskRunner(logger, timeout)
+	taskRunner := loadtester.NewTaskRunner(logger, timeout, logCmdOutput)
 
 	go taskRunner.Start(100*time.Millisecond, stopCh)
 
-	logger.Infof("Starting HTTP server on port %s", port)
+	logger.Infof("Starting load tester v%s API on port %s", VERSION, port)
 	loadtester.ListenAndServe(port, time.Minute, logger, taskRunner, stopCh)
 }

pkg/loadtester/runner.go

@@ -3,6 +3,7 @@ package loadtester
 import (
 	"context"
 	"encoding/hex"
+	"fmt"
 	"go.uber.org/zap"
 	"hash/fnv"
 	"os/exec"
@@ -17,6 +18,7 @@ type TaskRunner struct {
 	todoTasks    *sync.Map
 	runningTasks *sync.Map
 	totalExecs   uint64
+	logCmdOutput bool
 }
 
 type Task struct {
@@ -30,12 +32,13 @@ func (t Task) Hash() string {
 	return hex.EncodeToString(fnvBytes[:])
 }
 
-func NewTaskRunner(logger *zap.SugaredLogger, timeout time.Duration) *TaskRunner {
+func NewTaskRunner(logger *zap.SugaredLogger, timeout time.Duration, logCmdOutput bool) *TaskRunner {
 	return &TaskRunner{
 		logger:       logger,
 		todoTasks:    new(sync.Map),
 		runningTasks: new(sync.Map),
 		timeout:      timeout,
+		logCmdOutput: logCmdOutput,
 	}
 }
 
@@ -74,6 +77,9 @@ func (tr *TaskRunner) runAll() {
 				if err != nil {
 					tr.logger.With("canary", t.Canary).Errorf("command failed %s %v %s", t.Command, err, out)
 				} else {
+					if tr.logCmdOutput {
+						fmt.Printf("%s\n", out)
+					}
 					tr.logger.With("canary", t.Canary).Infof("command finished %s", t.Command)
 				}
 

pkg/loadtester/runner_test.go

@@ -9,7 +9,7 @@ import (
 func TestTaskRunner_Start(t *testing.T) {
 	stop := make(chan struct{})
 	logger, _ := logging.NewLogger("debug")
-	tr := NewTaskRunner(logger, time.Hour)
+	tr := NewTaskRunner(logger, time.Hour, false)
 
 	go tr.Start(10*time.Millisecond, stop)