viper.ConfigPaths()

main.go

package main

import (
	"fmt"
	"os"

	log "github.com/Sirupsen/logrus"

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

func main() {
	rootCmd := &cobra.Command{
		Use: "test",
		PersistentPreRun: func(cmd *cobra.Command, args []string) {
			if viper.GetBool("debug") {
				log.SetLevel(log.DebugLevel)
			}
		},
		PreRunE: func(cmd *cobra.Command, args []string) (err error) {
			config := viper.GetString("config")
			if config != "" {
				viper.SetConfigFile(config)
			}
			if err = viper.ReadInConfig(); err != nil {
				if _, ok := err.(viper.ConfigFileNotFoundError); !ok {
					return err
				}
				if config != "" {
					return err
				}
			}
			configUsed := viper.ConfigFileUsed()
			clog := log.WithFields(log.Fields{
				"config":    configUsed,
				"locations": viper.ConfigPaths(),
			})

			if configUsed == "" {
				clog.Warn("preflight complete")
			} else {
				clog.Info("preflight complete")
			}

			return nil
		},
		Run: func(cmd *cobra.Command, args []string) {
			fmt.Printf("run!\n")
		},
	}
	rootCmd.PersistentFlags().StringP("config", "c", "", "config file")
	viper.BindPFlag("config", rootCmd.PersistentFlags().Lookup("config"))
	rootCmd.PersistentFlags().BoolP("debug", "d", false, "debug output")
	viper.BindPFlag("debug", rootCmd.PersistentFlags().Lookup("debug"))

	viper.SetConfigName("config")
	viper.AddConfigPath(".")
	viper.AddConfigPath("etc/")
	viper.AutomaticEnv()

	if err := rootCmd.Execute(); err != nil {
		fmt.Printf("oops: %v\n", err)
		os.Exit(1)
	}
}