urfave-cli/docs/v2/examples/greet.md

tags	search
v2	boost 2

Being a programmer can be a lonely job. Thankfully by the power of automation that is not the case! Let's create a greeter app to fend off our demons of loneliness!

Start by creating a directory named greet, and within it, add a file, greet.go with the following code in it:

package main

import (
	"fmt"
	"log"
	"os"

	"github.com/urfave/cli/v2"
)

func main() {
	app := &cli.App{
		Name:  "greet",
		Usage: "fight the loneliness!",
		Action: func(*cli.Context) error {
			fmt.Println("Hello friend!")
			return nil
		},
	}

	if err := app.Run(os.Args); err != nil {
		log.Fatal(err)
	}
}

Install our command to the $GOPATH/bin directory:

$ go install

Finally run our new command:

$ greet
Hello friend!

cli also generates neat help text:

$ greet help
NAME:
    greet - fight the loneliness!

USAGE:
    greet [global options] command [command options] [arguments...]

COMMANDS:
    help, h  Shows a list of commands or help for one command

GLOBAL OPTIONS
    --help, -h  show help (default: false)