Simple GoBot Chat

gobot_chat.go

// Simple Chat Server. It does not broadcast to other people.
// It can be used to create a bot.
package main

import (
	"bufio"
	"fmt"
	"io"
	"log"
	"net"
	"time"
)

func main() {
	server, err := net.Listen("tcp", ":9000")
	if err != nil {
		log.Fatalln(err)
	}
	defer server.Close()

	for {
		conn, err := server.Accept()
		if err != nil {
			log.Fatalln(err)
		}
		go handler(New(), conn)
	}
}

func handler(chatServer *ChatServer, conn net.Conn) {
	defer conn.Close()

	scanner := bufio.NewScanner(conn)
	io.WriteString(conn, "Enter your username: ")

	scanner.Scan()
	chatServer.Username = scanner.Text()

	fmt.Fprintf(conn, "%s joined: \n", chatServer.Username)
	go func() {
		for scanner.Scan() {
			chatServer.Message <- scanner.Text()
		}
	}()

	for m := range chatServer.Message {
		t := time.Now().Format("15:04:05")
		s := fmt.Sprintf("%s %s [%s]: %s\n", t, conn.RemoteAddr(), chatServer.Username, m)
		fmt.Print(s)
		io.WriteString(conn, s)
	}
}

// ChatServer is a messenger.
type ChatServer struct {
	Username string
	Message  chan string
}

// New returns an instance of ChatServer.
func New() *ChatServer {
	return &ChatServer{Message: make(chan string)}
}