update doc w/ newer cmd/root.go example (spf13#973)

Author: jharshman

README.md

@@ -210,53 +210,72 @@ You will additionally define flags and handle configuration in your init() funct
 For example cmd/root.go:
 
 ```go
+package cmd
+
 import (
-  "fmt"
-  "os"
+	"fmt"
 
-  homedir "github.com/mitchellh/go-homedir"
-  "github.com/spf13/cobra"
-  "github.com/spf13/viper"
+	homedir "github.com/mitchellh/go-homedir"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
 )
 
-var cfgFile string
+var (
+	// Used for flags.
+	cfgFile     string
+	userLicense string
+
+	rootCmd = &cobra.Command{
+		Use:   "cobra",
+		Short: "A generator for Cobra based Applications",
+		Long: `Cobra is a CLI library for Go that empowers applications.
+This application is a tool to generate the needed files
+to quickly create a Cobra application.`,
+	}
+)
+
+// Execute executes the root command.
+func Execute() error {
+	return rootCmd.Execute()
+}
 
 func init() {
-  cobra.OnInitialize(initConfig)
-  rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.cobra.yaml)")
-  rootCmd.PersistentFlags().StringVarP(&projectBase, "projectbase", "b", "", "base project directory eg. github.com/spf13/")
-  rootCmd.PersistentFlags().StringP("author", "a", "YOUR NAME", "Author name for copyright attribution")
-  rootCmd.PersistentFlags().StringVarP(&userLicense, "license", "l", "", "Name of license for the project (can provide `licensetext` in config)")
-  rootCmd.PersistentFlags().Bool("viper", true, "Use Viper for configuration")
-  viper.BindPFlag("author", rootCmd.PersistentFlags().Lookup("author"))
-  viper.BindPFlag("projectbase", rootCmd.PersistentFlags().Lookup("projectbase"))
-  viper.BindPFlag("useViper", rootCmd.PersistentFlags().Lookup("viper"))
-  viper.SetDefault("author", "NAME HERE <EMAIL ADDRESS>")
-  viper.SetDefault("license", "apache")
+	cobra.OnInitialize(initConfig)
+
+	rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.cobra.yaml)")
+	rootCmd.PersistentFlags().StringP("author", "a", "YOUR NAME", "author name for copyright attribution")
+	rootCmd.PersistentFlags().StringVarP(&userLicense, "license", "l", "", "name of license for the project")
+	rootCmd.PersistentFlags().Bool("viper", true, "use Viper for configuration")
+	viper.BindPFlag("author", rootCmd.PersistentFlags().Lookup("author"))
+	viper.BindPFlag("useViper", rootCmd.PersistentFlags().Lookup("viper"))
+	viper.SetDefault("author", "NAME HERE <EMAIL ADDRESS>")
+	viper.SetDefault("license", "apache")
+
+	rootCmd.AddCommand(addCmd)
+	rootCmd.AddCommand(initCmd)
 }
 
 func initConfig() {
-  // Don't forget to read config either from cfgFile or from home directory!
-  if cfgFile != "" {
-    // Use config file from the flag.
-    viper.SetConfigFile(cfgFile)
-  } else {
-    // Find home directory.
-    home, err := homedir.Dir()
-    if err != nil {
-      fmt.Println(err)
-      os.Exit(1)
-    }
-
-    // Search config in home directory with name ".cobra" (without extension).
-    viper.AddConfigPath(home)
-    viper.SetConfigName(".cobra")
-  }
-
-  if err := viper.ReadInConfig(); err != nil {
-    fmt.Println("Can't read config:", err)
-    os.Exit(1)
-  }
+	if cfgFile != "" {
+		// Use config file from the flag.
+		viper.SetConfigFile(cfgFile)
+	} else {
+		// Find home directory.
+		home, err := homedir.Dir()
+		if err != nil {
+			er(err)
+		}
+
+		// Search config in home directory with name ".cobra" (without extension).
+		viper.AddConfigPath(home)
+		viper.SetConfigName(".cobra")
+	}
+
+	viper.AutomaticEnv()
+
+	if err := viper.ReadInConfig(); err == nil {
+		fmt.Println("Using config file:", viper.ConfigFileUsed())
+	}
 }
 ```