discordgo/examples/new_basic/main.go

package main

import (
	"flag"
	"fmt"
	"time"

	"github.com/bwmarrin/discordgo"
)

// Variables used for command line parameters
var (
	Token string
)

func init() {

	flag.StringVar(&Token, "t", "", "Bot Token")
	flag.Parse()
}

func main() {

	// Create a new Discord session using the provided bot token.
	dg, err := discordgo.New("Bot " + Token)
	if err != nil {
		fmt.Println("error creating Discord session,", err)
		return
	}

	// Register messageCreate as a callback for the messageCreate events.
	dg.AddHandler(messageCreate)

	// Open the websocket and begin listening.
	err = dg.Open()
	if err != nil {
		fmt.Println("error opening connection,", err)
		return
	}

	fmt.Println("Bot is now running.  Press CTRL-C to exit.")
	// Simple way to keep program running until CTRL-C is pressed.
	<-make(chan struct{})
	return
}

// This function will be called (due to AddHandler above) every time a new
// message is created on any channel that the autenticated bot has access to.
func messageCreate(s *discordgo.Session, m *discordgo.MessageCreate) {

	// Print message to stdout.
	fmt.Printf("%20s %20s %20s > %s\n", m.ChannelID, time.Now().Format(time.Stamp), m.Author.Username, m.Content)
}