fix(helm): fix error formatting

This fixes a number of issues with error formatting and handling in the
client.

Closes #668

cmd/helm/delete.go

@@ -34,7 +34,7 @@ func init() {
 
 func delRelease(cmd *cobra.Command, args []string) error {
 	if len(args) == 0 {
-		return errors.New("Command 'delete' requires a release name.")
+		return errors.New("command 'delete' requires a release name")
 	}
 
 	// TODO: Handle dry run use case.
@@ -45,7 +45,7 @@ func delRelease(cmd *cobra.Command, args []string) error {
 
 	_, err := helm.UninstallRelease(args[0])
 	if err != nil {
-		return err
+		return prettyError(err)
 	}
 
 	return nil

cmd/helm/get.go

@@ -81,7 +81,7 @@ func getCmd(cmd *cobra.Command, args []string) error {
 
 	res, err := helm.GetReleaseContent(args[0])
 	if err != nil {
-		return err
+		return prettyError(err)
 	}
 
 	fmt.Printf("CHART: %s-%s\n", res.Release.Chart.Metadata.Name, res.Release.Chart.Metadata.Version)
@@ -101,7 +101,7 @@ func getValues(cmd *cobra.Command, args []string) error {
 
 	res, err := helm.GetReleaseContent(args[0])
 	if err != nil {
-		return err
+		return prettyError(err)
 	}
 	return getToFile(res.Release.Config)
 }
@@ -114,7 +114,7 @@ func getManifest(cmd *cobra.Command, args []string) error {
 
 	res, err := helm.GetReleaseContent(args[0])
 	if err != nil {
-		return err
+		return prettyError(err)
 	}
 	return getToFile(res.Release.Manifest)
 }

cmd/helm/helm.go

@@ -1,11 +1,13 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"os"
 	"strings"
 
 	"github.com/spf13/cobra"
+	"google.golang.org/grpc"
 )
 
 var stdout = os.Stdout
@@ -48,7 +50,9 @@ func init() {
 }
 
 func main() {
-	RootCommand.Execute()
+	if err := RootCommand.Execute(); err != nil {
+		os.Exit(1)
+	}
 }
 
 func checkArgsLength(expectedNum, actualNum int, requiredArgs ...string) error {
@@ -61,3 +65,11 @@ func checkArgsLength(expectedNum, actualNum int, requiredArgs ...string) error {
 	}
 	return nil
 }
+
+// prettyError unwraps or rewrites certain errors to make them more user-friendly.
+func prettyError(err error) error {
+	// This is ridiculous. Why is 'grpc.rpcError' not exported? The least they
+	// could do is throw an interface on the lib that would let us get back
+	// the desc. Instead, we have to pass ALL errors through this.
+	return errors.New(grpc.ErrorDesc(err))
+}

cmd/helm/install.go

@@ -42,11 +42,15 @@ var installCmd = &cobra.Command{
 }
 
 func runInstall(cmd *cobra.Command, args []string) error {
-	setupInstallEnv(args)
+	if err := checkArgsLength(1, len(args), "chart name"); err != nil {
+		return err
+	}
+	installArg = args[0]
+	setupInstallEnv()
 
 	res, err := helm.InstallRelease(installArg, installDryRun)
 	if err != nil {
-		return err
+		return prettyError(err)
 	}
 
 	printRelease(res.GetRelease())
@@ -54,9 +58,6 @@ func runInstall(cmd *cobra.Command, args []string) error {
 	return nil
 }
 
-// TODO -- Display formatted description of install release status / info.
-// 		   Might be friendly to wrap our proto model with pretty-printers.
-//
 func printRelease(rel *release.Release) {
 	if rel == nil {
 		return
@@ -71,16 +72,13 @@ func printRelease(rel *release.Release) {
 	}
 }
 
-func setupInstallEnv(args []string) {
-	if len(args) > 0 {
-		installArg = args[0]
-	} else {
-		fatalf("This command needs at least one argument, the name of the chart.")
-	}
-
-	// note: TILLER_HOST envvar is only
+func setupInstallEnv() {
+	// note: TILLER_HOST envvar is
 	// acknowledged iff the host flag
 	// does not override the default.
+	//
+	// bug: except that if the host flag happens to set the host to the same
+	// value as the defaultHost, the env var will be used instead.
 	if tillerHost == defaultHost {
 		host := os.Getenv(hostEnvVar)
 		if host != "" {
@@ -91,11 +89,6 @@ func setupInstallEnv(args []string) {
 	helm.Config.ServAddr = tillerHost
 }
 
-func fatalf(format string, args ...interface{}) {
-	fmt.Printf("fatal: %s\n", fmt.Sprintf(format, args...))
-	os.Exit(0)
-}
-
 func init() {
 	installCmd.Flags().StringVar(&tillerHost, "host", defaultHost, "address of tiller server")
 	installCmd.Flags().BoolVar(&installDryRun, "dry-run", false, "simulate an install")

cmd/helm/list.go

@@ -47,7 +47,7 @@ func listCmd(cmd *cobra.Command, args []string) error {
 
 	res, err := helm.ListReleases(listMax, listOffset)
 	if err != nil {
-		return err
+		return prettyError(err)
 	}
 
 	rels := res.Releases

cmd/helm/status.go

@@ -30,7 +30,7 @@ func status(cmd *cobra.Command, args []string) error {
 
 	res, err := helm.GetReleaseStatus(args[0])
 	if err != nil {
-		return err
+		return prettyError(err)
 	}
 
 	fmt.Printf("Last Deployed: %s\n", timeconv.String(res.Info.LastDeployed))