Support using a custom file name

go/blog/blog.go

var flags struct {
	writeBack bool
}
var dataPath string = "blog.yaml"
func init() {
	flag.BoolVar(&flags.writeBack, "write-back", false, "Rewrite the YAML file with the generated ids")
func main() {
	flag.Parse()
	f, err := os.Open("blog.yaml")
	if flag.NArg() > 0 {
		dataPath = flag.Arg(0)
	}
	f, err := os.Open(dataPath)
	if err != nil {
		exit(err)
	}
		if err != nil {
			exit(err)
		}
		ioutil.WriteFile("blog.yaml", out, 0664)
		ioutil.WriteFile(dataPath, out, 0664)
	}
}