Do not output k6 banner and test description when --quiet is enabled

cmd/cloud.go

@@ -89,8 +89,7 @@ This will execute the test on the k6 cloud service. Use "k6 login cloud" to auth
 			return nil
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
-			// TODO: disable in quiet mode?
-			_, _ = fmt.Fprintf(globalState.stdOut, "\n%s\n\n", getBanner(globalState.flags.noColor || !globalState.stdOut.isTTY))
+			printBanner(globalState)
 
 			logger := globalState.logger
 			progressBar := pb.New(
@@ -344,8 +343,14 @@ This will execute the test on the k6 cloud service. Use "k6 login cloud" to auth
 				return errext.WithExitCodeIfNone(errors.New("Test progress error"), exitcodes.CloudFailedToGetProgress)
 			}
 
-			valueColor := getColor(globalState.flags.noColor || !globalState.stdOut.isTTY, color.FgCyan)
-			fprintf(globalState.stdOut, "     test status: %s\n", valueColor.Sprint(testProgress.RunStatusText))
+			if !globalState.flags.quiet {
+				valueColor := getColor(globalState.flags.noColor || !globalState.stdOut.isTTY, color.FgCyan)
+				printToStdout(globalState, fmt.Sprintf(
+					"     test status: %s\n", valueColor.Sprint(testProgress.RunStatusText),
+				))
+			} else {
+				logger.WithField("run_status", testProgress.RunStatusText).Debug("Test finished")
+			}
 
 			if testProgress.ResultStatus == cloudapi.ResultStatusFailed {
 				// TODO: use different exit codes for failed thresholds vs failed test (e.g. aborted by system/limit)

cmd/common.go

@@ -24,7 +24,6 @@ import (
 	"archive/tar"
 	"bytes"
 	"fmt"
-	"io"
 
 	"github.com/spf13/afero"
 	"github.com/spf13/cobra"
@@ -107,11 +106,8 @@ func detectType(data []byte) string {
 	return typeJS
 }
 
-// fprintf panics when where's an error writing to the supplied io.Writer
-func fprintf(w io.Writer, format string, a ...interface{}) (n int) {
-	n, err := fmt.Fprintf(w, format, a...)
-	if err != nil {
-		panic(err.Error())
+func printToStdout(gs *globalState, s string) {
+	if _, err := fmt.Fprint(gs.stdOut, s); err != nil {
+		gs.logger.Errorf("could not print '%s' to stdout: %s", s, err.Error())
 	}
-	return n
 }

cmd/login_cloud.go

@@ -23,6 +23,7 @@ package cmd
 import (
 	"encoding/json"
 	"errors"
+	"fmt"
 	"syscall"
 
 	"github.com/fatih/color"
@@ -86,7 +87,7 @@ This will set the default token used when just "k6 run -o cloud" is passed.`,
 			switch {
 			case reset.Valid:
 				newCloudConf.Token = null.StringFromPtr(nil)
-				fprintf(globalState.stdOut, "  token reset\n")
+				printToStdout(globalState, "  token reset\n")
 			case show.Bool:
 			case token.Valid:
 				newCloudConf.Token = token
@@ -147,7 +148,7 @@ This will set the default token used when just "k6 run -o cloud" is passed.`,
 
 			if newCloudConf.Token.Valid {
 				valueColor := getColor(globalState.flags.noColor || !globalState.stdOut.isTTY, color.FgCyan)
-				fprintf(globalState.stdOut, "  token: %s\n", valueColor.Sprint(newCloudConf.Token.String))
+				printToStdout(globalState, fmt.Sprintf("  token: %s\n", valueColor.Sprint(newCloudConf.Token.String)))
 			}
 			return nil
 		},

cmd/run.go

@@ -88,8 +88,7 @@ a commandline interface for interacting with it.`,
   k6 run -o influxdb=http://1.2.3.4:8086/k6`[1:],
 		Args: exactArgsWithMsg(1, "arg should either be \"-\", if reading script from stdin, or a path to a script file"),
 		RunE: func(cmd *cobra.Command, args []string) error {
-			// TODO: disable in quiet mode?
-			_, _ = fmt.Fprintf(globalState.stdOut, "\n%s\n\n", getBanner(globalState.flags.noColor || !globalState.stdOut.isTTY))
+			printBanner(globalState)
 
 			logger := globalState.logger
 			logger.Debug("Initializing the runner...")
@@ -328,7 +327,9 @@ a commandline interface for interacting with it.`,
 					// do nothing, we were interrupted by Ctrl+C already
 				default:
 					logger.Debug("Linger set; waiting for Ctrl+C...")
-					fprintf(globalState.stdOut, "Linger set; waiting for Ctrl+C...")
+					if !globalState.flags.quiet {
+						printToStdout(globalState, "Linger set; waiting for Ctrl+C...")
+					}
 					<-lingerCtx.Done()
 					logger.Debug("Ctrl+C received, exiting...")
 				}

cmd/ui.go

@@ -104,6 +104,18 @@ func getBanner(noColor bool) string {
 	return c.Sprint(consts.Banner())
 }
 
+func printBanner(gs *globalState) {
+	if gs.flags.quiet {
+		return // do not print banner when --quiet is enabled
+	}
+
+	banner := getBanner(gs.flags.noColor || !gs.stdOut.isTTY)
+	_, err := fmt.Fprintf(gs.stdOut, "\n%s\n\n", banner)
+	if err != nil {
+		gs.logger.Warnf("could not print k6 banner message to stdout: %s", err.Error())
+	}
+}
+
 func printBar(gs *globalState, bar *pb.ProgressBar) {
 	if gs.flags.quiet {
 		return
@@ -124,7 +136,7 @@ func printBar(gs *globalState, bar *pb.ProgressBar) {
 	}
 	rendered := bar.Render(0, widthDelta)
 	// Only output the left and middle part of the progress bar
-	fprintf(gs.stdOut, "%s%s", rendered.String(), end)
+	printToStdout(gs, rendered.String()+end)
 }
 
 func modifyAndPrintBar(gs *globalState, bar *pb.ProgressBar, options ...pb.ProgressBarOption) {
@@ -141,8 +153,9 @@ func printExecutionDescription(
 	noColor := gs.flags.noColor || !gs.stdOut.isTTY
 	valueColor := getColor(noColor, color.FgCyan)
 
-	fprintf(gs.stdOut, "  execution: %s\n", valueColor.Sprint(execution))
-	fprintf(gs.stdOut, "     script: %s\n", valueColor.Sprint(filename))
+	buf := &strings.Builder{}
+	fmt.Fprintf(buf, "  execution: %s\n", valueColor.Sprint(execution))
+	fmt.Fprintf(buf, "     script: %s\n", valueColor.Sprint(filename))
 
 	var outputDescriptions []string
 	switch {
@@ -156,8 +169,8 @@ func printExecutionDescription(
 		}
 	}
 
-	fprintf(gs.stdOut, "     output: %s\n", valueColor.Sprint(strings.Join(outputDescriptions, ", ")))
-	fprintf(gs.stdOut, "\n")
+	fmt.Fprintf(buf, "     output: %s\n", valueColor.Sprint(strings.Join(outputDescriptions, ", ")))
+	fmt.Fprintf(buf, "\n")
 
 	maxDuration, _ := lib.GetEndOffset(execPlan)
 	executorConfigs := conf.Scenarios.GetSortedConfigs()
@@ -167,16 +180,22 @@ func printExecutionDescription(
 		scenarioDesc = fmt.Sprintf("%d scenarios", len(executorConfigs))
 	}
 
-	fprintf(gs.stdOut, "  scenarios: %s\n", valueColor.Sprintf(
+	fmt.Fprintf(buf, "  scenarios: %s\n", valueColor.Sprintf(
 		"(%.2f%%) %s, %d max VUs, %s max duration (incl. graceful stop):",
 		conf.ExecutionSegment.FloatLength()*100, scenarioDesc,
 		lib.GetMaxPossibleVUs(execPlan), maxDuration.Round(100*time.Millisecond)),
 	)
 	for _, ec := range executorConfigs {
-		fprintf(gs.stdOut, "           * %s: %s\n",
+		fmt.Fprintf(buf, "           * %s: %s\n",
 			ec.GetName(), ec.GetDescription(et))
 	}
-	fprintf(gs.stdOut, "\n")
+	fmt.Fprintf(buf, "\n")
+
+	if gs.flags.quiet {
+		gs.logger.Debug(buf.String())
+	} else {
+		printToStdout(gs, buf.String())
+	}
 }
 
 //nolint: funlen

cmd/version.go

@@ -33,7 +33,7 @@ func getVersionCmd(globalState *globalState) *cobra.Command {
 		Short: "Show application version",
 		Long:  `Show the application version and exit.`,
 		Run: func(_ *cobra.Command, _ []string) {
-			fprintf(globalState.stdOut, "k6 v%s", consts.FullVersion())
+			printToStdout(globalState, "k6 v"+consts.FullVersion())
 		},
 	}
 	return versionCmd