I want to call a specific function based on a command line flag. The relevant parts of my code currently look like this:

package main

...

var enctool string

type encryptionFunction func(string, string) *os.File

func main() {

    var ef encryptionFunction

        // get encryption tool from flags, default to age
    flag.StringVar(&enctool, "t", "age", "Encryption tool (age|gpg)")
    flag.Parse()

    // decide encryption backend
    switch enctool {
    case "age":
        ef = encrypt.AgeEncrypt
    case "gpg":
        ef = encrypt.GPGEncrypt
    default:
        println("No encryption tool defined.")
        return
    }

    // encrypt input file, output to tmpfile
    tmpfile := ef(flag.Arg(0), recipient)
...
}

This works as I expect it to, but here’s the question:

Is this a legit way to handle this kind of flow or is there a more Go -appropriate approach, and if so what would be the benefit? Should I be looking at something like interfaces to handle this?