spf13--cobra/cobra/cmd/root.go

// Copyright © 2015 Steve Francia <spf@spf13.com>.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package cmd

import (
	"fmt"
	"os"

	"github.com/spf13/cobra"
	"github.com/spf13/viper"
)

var cfgFile string
var userLicense string

// RootCmd represents the base command when called without any subcommands
var 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 adds all child commands to the root command sets flags appropriately.
func Execute() {
	if err := RootCmd.Execute(); err != nil {
		fmt.Println(err)
		os.Exit(-1)
	}
}

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, e.g. 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 `license` 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")
}

// Read in config file and ENV variables if set.
func initConfig() {
	if cfgFile != "" { // enable ability to specify config file via flag
		viper.SetConfigFile(cfgFile)
	}

	viper.SetConfigName(".cobra") // name of config file (without extension)
	viper.AddConfigPath("$HOME")  // adding home directory as first search path
	viper.AddConfigPath(".")      // optionally look for config in working directory
	viper.AutomaticEnv()          // read in environment variables that match

	// If a config file is found, read it in.
	if err := viper.ReadInConfig(); err == nil {
		fmt.Println("Using config file:", viper.ConfigFileUsed())
	}
}