mixer: reduce noise when commands fail

Only print errors once, not twice. Do not print usage information
unless the command was called with invalid arguments.

Because cobra already print its own errors, don't print them again in
Execute function, just ensure we get the right exit code. Mixer errors
will be handled by our code, instead of passing the errors to cobra
and then later get them back. That way no usage is printed.

Two helper functions were added fail/failf to perform Print+Exit.

Signed-off-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>

mixer/cmd/build.go

@@ -72,68 +72,68 @@ var buildChrootsCmd = &cobra.Command{
 	Use:   "chroots",
 	Short: "Build the chroots for your mix",
 	Long:  `Build the chroots for your mix`,
-	RunE: func(cmd *cobra.Command, args []string) error {
+	Run: func(cmd *cobra.Command, args []string) {
 		b := builder.NewFromConfig(config)
-		return buildChroots(b, buildFlags.noSigning)
+		err := buildChroots(b, buildFlags.noSigning)
+		if err != nil {
+			fail(err)
+		}
 	},
 }
 
 var buildUpdateCmd = &cobra.Command{
 	Use:   "update",
 	Short: "Build the update content for your mix",
 	Long:  `Build the update content for your mix`,
-	RunE: func(cmd *cobra.Command, args []string) error {
+	Run: func(cmd *cobra.Command, args []string) {
 		b := builder.NewFromConfig(config)
 		err := b.BuildUpdate(buildFlags.prefix, buildFlags.minVersion, buildFlags.format, buildFlags.noSigning, !buildFlags.noPublish, buildFlags.keepChroot)
 		if err != nil {
-			return errors.Wrap(err, "couldn't build update")
+			failf("couldn't build update: %s", err)
 		}
 
 		if buildFlags.increment {
 			b.UpdateMixVer()
 		}
-		return nil
 	},
 }
 
 var buildAllCmd = &cobra.Command{
 	Use:   "all",
 	Short: "Build all content for mix with default options",
 	Long:  `Build all content for mix with default options`,
-	RunE: func(cmd *cobra.Command, args []string) error {
+	Run: func(cmd *cobra.Command, args []string) {
 		b := builder.NewFromConfig(config)
 		rpms, err := ioutil.ReadDir(b.RPMdir)
 		if err == nil {
 			err = b.AddRPMList(rpms)
 			if err != nil {
-				return errors.Wrap(err, "couldn't add the RPMs")
+				failf("couldn't add the RPMs: %s", err)
 			}
 		}
 		err = buildChroots(b, buildFlags.noSigning)
 		if err != nil {
-			return errors.Wrap(err, "Error building chroots")
+			failf("couldn't build chroots: %s", err)
 		}
 		err = b.BuildUpdate(buildFlags.prefix, buildFlags.minVersion, buildFlags.format, buildFlags.noSigning, !buildFlags.noPublish, buildFlags.keepChroot)
 		if err != nil {
-			return errors.Wrap(err, "Error building update")
+			failf("couldn't build update: %s", err)
 		}
 
 		b.UpdateMixVer()
-		return nil
 	},
 }
 
 var buildImageCmd = &cobra.Command{
 	Use:   "image",
 	Short: "Build an image from the mix content",
 	Long:  `Build an image from the mix content`,
-	RunE: func(cmd *cobra.Command, args []string) error {
+	Run: func(cmd *cobra.Command, args []string) {
 		b := builder.NewFromConfig(config)
 		err := b.BuildImage(buildFlags.format, buildFlags.template)
 		if err != nil {
-			return errors.Wrap(err, "Error building image")
+			failf("couldn't build image: %s", err)
 		}
-		return nil
 	},
 }
 

mixer/cmd/bundles.go

@@ -20,7 +20,6 @@ import (
 
 	"github.com/clearlinux/mixer-tools/builder"
 
-	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 )
 
@@ -41,31 +40,29 @@ var addBundlesCmd = &cobra.Command{
 	Use:   "add [bundle(s)]",
 	Short: "Add clr-bundles to your mix",
 	Long:  `Add clr-bundles to your mix`,
-	RunE: func(cmd *cobra.Command, args []string) error {
+	Run: func(cmd *cobra.Command, args []string) {
 		if bundleFlags.all == false {
 			if len(args) <= 0 {
-				return errors.New("bundle add requires at least 1 argument if --all is not passed")
+				failf("bundle add requires at least 1 argument if --all is not passed")
 			}
 		}
 		bundles := strings.Split(args[0], ",")
 		b := builder.NewFromConfig(config)
 		// TODO change this to return (int, error)
 		numadded := b.AddBundles(bundles, bundleFlags.force, bundleFlags.all, bundleFlags.git)
 		fmt.Println(numadded, " bundles were added")
-		return nil
 	},
 }
 
 var getBundlesCmd = &cobra.Command{
 	Use:   "get",
 	Short: "Get the clr-bundles from upstream",
 	Long:  `Get the clr-bundles from upstream`,
-	RunE: func(cmd *cobra.Command, args []string) error {
+	Run: func(cmd *cobra.Command, args []string) {
 		b := builder.NewFromConfig(config)
 		fmt.Println("Getting clr-bundles for version " + b.Clearver)
 		// TODO change this to return an error
 		b.UpdateRepo(b.Clearver, false)
-		return nil
 	},
 }
 

mixer/cmd/root.go

@@ -46,19 +46,21 @@ var initCmd = &cobra.Command{
 	Use:   "init-mix",
 	Short: "Initialize the mixer and workspace",
 	Long:  `Initialize the mixer and workspace`,
-	RunE: func(cmd *cobra.Command, args []string) error {
+	Run: func(cmd *cobra.Command, args []string) {
 		b := builder.New()
 		b.LoadBuilderConf(config)
 		b.ReadBuilderConf()
-		return b.InitMix(strconv.Itoa(initFlags.clearver), strconv.Itoa(initFlags.mixver), initFlags.all, initFlags.upstreamurl)
+		err := b.InitMix(strconv.Itoa(initFlags.clearver), strconv.Itoa(initFlags.mixver), initFlags.all, initFlags.upstreamurl)
+		if err != nil {
+			fail(err)
+		}
 	},
 }
 
 // Execute adds all child commands to the root command and sets flags appropriately.
 // This is called by main.main(). It only needs to happen once to the rootCmd.
 func Execute() {
 	if err := RootCmd.Execute(); err != nil {
-		fmt.Fprintf(os.Stderr, "Mixer Error: %s\n", err)
 		os.Exit(1)
 	}
 }
@@ -96,3 +98,13 @@ func init() {
 	initCmd.Flags().StringVar(&config, "config", "", "Supply a specific builder.conf to use for mixing")
 	initCmd.Flags().StringVar(&initFlags.upstreamurl, "upstream-url", "https://download.clearlinux.org", "Supply an upstream URL to use for mixing")
 }
+
+func fail(err error) {
+	fmt.Fprintf(os.Stderr, "ERROR: %s\n", err)
+	os.Exit(1)
+}
+
+func failf(format string, a ...interface{}) {
+	fmt.Fprintf(os.Stderr, fmt.Sprintf("ERROR: %s\n", format), a...)
+	os.Exit(1)
+}

mixer/cmd/rpms.go

@@ -19,15 +19,14 @@ import (
 
 	"github.com/clearlinux/mixer-tools/builder"
 
-	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 )
 
 var addRPMCmd = &cobra.Command{
 	Use:   "add-rpms",
 	Short: "Add RPMs to local yum repository",
 	Long:  `Add RPMS from the configured RPMDIR to local yum repository`,
-	RunE:  runAddRPM,
+	Run:   runAddRPM,
 }
 
 var rpmCmds = []*cobra.Command{
@@ -41,14 +40,17 @@ func init() {
 	}
 }
 
-func runAddRPM(cmd *cobra.Command, args []string) error {
+func runAddRPM(cmd *cobra.Command, args []string) {
 	b := builder.NewFromConfig(config)
 	if b.RPMdir == "" {
-		return errors.Errorf("RPMDIR not set in configuration")
+		failf("RPMDIR not set in configuration")
 	}
 	rpms, err := ioutil.ReadDir(b.RPMdir)
 	if err != nil {
-		return errors.Wrapf(err, "cannot read RPMDIR")
+		failf("cannot read RPMDIR: %s", err)
+	}
+	err = b.AddRPMList(rpms)
+	if err != nil {
+		fail(err)
 	}
-	return b.AddRPMList(rpms)
 }