Allow stages to be properly disabled by fixing the CLI parsing

cmd/config_test.go

@@ -83,6 +83,8 @@ func TestConfigCmd(t *testing.T) {
 	}
 }
 
+//TODO: write end-to-end configuration tests - how the config file, in-script options, environment variables and CLI flags are parsed and interact... and how the end result is then propagated back into the script
+
 func TestConfigEnv(t *testing.T) {
 	testdata := map[struct{ Name, Key string }]map[string]func(Config){
 		{"Linger", "K6_LINGER"}: {

cmd/options.go

@@ -96,18 +96,22 @@ func getOptions(flags *pflag.FlagSet) (lib.Options, error) {
 		MetricSamplesBufferSize: null.NewInt(1000, false),
 	}
 
-	stageStrings, err := flags.GetStringSlice("stage")
-	if err != nil {
-		return opts, err
-	}
-	if len(stageStrings) > 0 {
-		opts.Stages = make([]lib.Stage, len(stageStrings))
+	// Using Lookup() because GetStringSlice() doesn't differentiate between --stage="" and no value
+	if flags.Lookup("stage").Changed {
+		stageStrings, err := flags.GetStringSlice("stage")
+		if err != nil {
+			return opts, err
+		}
+		opts.Stages = []lib.Stage{}
 		for i, s := range stageStrings {
 			var stage lib.Stage
 			if err := stage.UnmarshalText([]byte(s)); err != nil {
 				return opts, errors.Wrapf(err, "stage %d", i)
 			}
-			opts.Stages[i] = stage
+			if !stage.Duration.Valid {
+				return opts, fmt.Errorf("stage %d doesn't have a specified duration", i)
+			}
+			opts.Stages = append(opts.Stages, stage)
 		}
 	}
 

cmd/run.go

@@ -143,7 +143,7 @@ a commandline interface for interacting with it.`,
 		}
 
 		// If -d/--duration, -i/--iterations and -s/--stage are all unset, run to one iteration.
-		if !conf.Duration.Valid && !conf.Iterations.Valid && conf.Stages == nil {
+		if !conf.Duration.Valid && !conf.Iterations.Valid && len(conf.Stages) == 0 {
 			conf.Iterations = null.IntFrom(1)
 		}
 

core/local/local.go

@@ -279,7 +279,7 @@ func (e *Executor) Run(parent context.Context, engineOut chan<- stats.SampleCont
 			}
 
 			stages := e.stages
-			if stages != nil {
+			if len(stages) > 0 {
 				vus, keepRunning := ProcessStages(startVUs, stages, at)
 				if !keepRunning {
 					e.Logger.WithField("at", at).Debug("Local: Ran out of stages")

release notes/upcoming.md

@@ -103,4 +103,5 @@ Thanks to @AndriiChuzhynov for implementing this! (#766)
 * Config: Stages were appended instead of overwritten from upper config "tiers", and were doubled when supplied via the CLI flag (#759)
 * HAR converter: Fixed a panic due to a missing array length check (#760)
 * HTTP: `http.batch()` calls could panic because of a data race when the `batchPerHost` global option was used (#770)
-* Docker: Fixed the grafana image in the docker-compose setup. Thanks @entone and @mariolopjr! (#783)
+* Docker: Fixed the grafana image in the docker-compose setup. Thanks @entone and @mariolopjr! (#783)
+* Config: Stages configured via the script `options` or environment variables couldn't be disabled via the CLI flags (#786)