fix(helm): allow TILLER_HOME to be used everywhere

This refactors handling of the TILLER_HOME and HELM_HOME env vars so
that they can be set once and used everywhere. Individual commands no
longer need to handle setting.

cmd/helm/helm.go

@@ -6,11 +6,20 @@ import (
 	"os"
 	"strings"
 
+	"github.com/kubernetes/helm/pkg/helm"
 	"github.com/spf13/cobra"
 	"google.golang.org/grpc"
 )
 
+const (
+	homeEnvVar  = "HELM_HOME"
+	defaultHome = "$HOME/.helm" // FIXME: is $HOME windows compatible?
+	hostEnvVar  = "TILLER_HOST"
+	defaultHost = ":44134"
+)
+
 var helmHome string
+var tillerHost string
 
 // flagVerbose is a signal that the user wants additional output.
 var flagVerbose bool
@@ -33,18 +42,30 @@ Common actions from this point include:
 
 Environment:
   $HELM_HOME    Set an alternative location for Helm files. By default, these are stored in ~/.helm
+  $TILLER_HOST  Set an alternative Tiller host. The format is host:port (default ":44134").
 `
 
 // RootCommand is the top-level command for Helm.
 var RootCommand = &cobra.Command{
-	Use:   "helm",
-	Short: "The Helm package manager for Kubernetes.",
-	Long:  globalUsage,
+	Use:              "helm",
+	Short:            "The Helm package manager for Kubernetes.",
+	Long:             globalUsage,
+	PersistentPreRun: bootstrap,
 }
 
 func init() {
-	RootCommand.PersistentFlags().StringVar(&helmHome, "home", "$HOME/.helm", "location of your Helm config")
-	RootCommand.PersistentFlags().BoolVarP(&flagVerbose, "verbose", "v", false, "enable verbose output")
+	home := os.Getenv(homeEnvVar)
+	if home == "" {
+		home = "$HOME/.helm"
+	}
+	thost := os.Getenv(hostEnvVar)
+	if thost == "" {
+		thost = defaultHost
+	}
+	p := RootCommand.PersistentFlags()
+	p.StringVar(&helmHome, "home", home, "location of your Helm config. Overrides $HELM_HOME.")
+	p.StringVar(&tillerHost, "host", thost, "address of tiller. Overrides $TILLER_HOST.")
+	p.BoolVarP(&flagVerbose, "verbose", "v", false, "enable verbose output")
 }
 
 func main() {
@@ -53,6 +74,11 @@ func main() {
 	}
 }
 
+func bootstrap(c *cobra.Command, args []string) {
+	// Set up the gRPC config.
+	helm.Config.ServAddr = tillerHost
+}
+
 func checkArgsLength(expectedNum, actualNum int, requiredArgs ...string) error {
 	if actualNum != expectedNum {
 		arg := "arguments"

cmd/helm/install.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"fmt"
-	"os"
 
 	"github.com/spf13/cobra"
 
@@ -19,17 +18,10 @@ path to a chart directory or the name of a
 chart in the current working directory.
 `
 
-const (
-	hostEnvVar  = "TILLER_HOST"
-	defaultHost = ":44134"
-)
-
 // install flags & args
 var (
 	// installArg is the name or relative path of the chart to install
 	installArg string
-	// tillerHost overrides TILLER_HOST envVar
-	tillerHost string
 	// installDryRun performs a dry-run install
 	installDryRun bool
 )
@@ -46,7 +38,6 @@ func runInstall(cmd *cobra.Command, args []string) error {
 		return err
 	}
 	installArg = args[0]
-	setupInstallEnv()
 
 	res, err := helm.InstallRelease(installArg, installDryRun)
 	if err != nil {
@@ -72,23 +63,7 @@ func printRelease(rel *release.Release) {
 	}
 }
 
-func setupInstallEnv() {
-	// The 'host' flag takes precendence uber alles.
-	// If set, proceed with install using provided host
-	// address. If unset, the 'TILLER_HOST' environment
-	// variable (if set) is used, otherwise defaults to ":44134".
-	if tillerHost == "" {
-		tillerHost = os.Getenv(hostEnvVar)
-		if tillerHost == "" {
-			tillerHost = defaultHost
-		}
-	}
-
-	helm.Config.ServAddr = tillerHost
-}
-
 func init() {
-	installCmd.Flags().StringVar(&tillerHost, "host", "", "address of tiller server (default \":44134\")")
 	installCmd.Flags().BoolVar(&installDryRun, "dry-run", false, "simulate an install")
 
 	RootCommand.AddCommand(installCmd)