Sample code testing use of an ini file with go-flags - config file is a callback

goflags_ini.go

package main

import (
	"fmt"

	flag "github.com/jessevdk/go-flags"
)

type Opts struct {
	TestFlag string `short:"t" description:"just here to aid in testing ini files and defaults" default:"default"`
	// ConfigFile func(s string) error `short:"c" long:"config" description:"config file for in ini format" no-ini:"true"`
	ConfigFile func(s string) error `short:"c" long:"config" description:"config file for in ini format" no-ini:"true" default:"ft.ini"`
}

func main() {
	var opts Opts
	fp := flag.NewParser(&opts, flag.PrintErrors)

	// read the config file if present
	opts.ConfigFile = func(s string) error {
		ini := flag.NewIniParser(fp)
		ini.ParseAsDefaults = true
		return ini.ParseFile(s)
	}

	fp.Parse()

	fmt.Printf("options: %+v\n", opts)

}