Flags binding doesn't work when trying to bind a flag to a nested key

[eugene-manuilov]

flags.StringP("env-file", "e", "", "...")
if err := viper.BindPFlag("config.env-file", flags.Lookup("env-file")); err != nil {
    panic(err)
}

...

envfile := viper.GetString( "config.env-file" )
fmt.Println("Env file: ", envfile)

Expected behavior (what you expected to happen):

$ mycmd --env-file=env.ini
$ Env file: env.ini

Actual behavior (what actually happened):

$ mycmd --env-file=env.ini
$ Env file: 

Repl.it link:

Code reproducing the issue:

Environment:

• Viper version: v1.7.1
• Config source: flag
• File format:

Anything else we should know?:

[github-actions[bot]]

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[thspinto]

I was trying the same thing in my integration with cobra. I used this workaround for my case:

func init() {
    rootCmd.AddCommand(serverCmd)
    serverCmd.Flags().StringP("port", "p", "", "server port")
    serverCmd.Flags().VisitAll(configureViper("server"))
}

func configureViper(prefix string) (fn func(*pflag.Flag)) {
    return func(flag *pflag.Flag) {
        prefixedName := strings.Join([]string{prefix, flag.Name}, ".")
        if err := viper.BindPFlag(prefixedName, flag); err != nil {
            panic(err)
        }
        env := strings.ReplaceAll(prefixedName, ".", "_")
        viper.BindEnv(prefixedName, strings.ToUpper(env))
    }
}

I basically iterate though all flags, manually configuring the viper and environment variable biding.