9wNJfzkG

1package main
2
3// A basic Twitch client that simply dumps out text from the Twitch IRC server
4// and prints it, and accepts commands from stdin and sends them.
5
6import (
7	"bufio"
8	"crypto/tls"
9	"fmt"
10	"net"
11	"os"
12	"os/signal"
13	"strings"
14)
15
16const twitchURL = "irc.chat.twitch.tv:6697"
17
18func main() {
19	nick := os.Getenv("BOT_USERNAME")
20	oauth := os.Getenv("OAUTH_TOKEN")
21
22	if nick == "" || oauth == "" {
23		fmt.Println("Specify both BOT_USERNAME and OAUTH_TOKEN environment variables.")
24		return
25	}
26
27	conn, err := tls.Dial("tcp", twitchURL, nil)
28	if err != nil {
29		fmt.Printf("TLS connection to %q did not succeed: %v\n", twitchURL, err)
30		return
31	}
32	defer conn.Close()
33
34	fmt.Println("PASS <elided>")
35	fmt.Fprintf(conn, "PASS %s\r\n", oauth) // Don't call send to avoid echoing the token.
36	send(conn, "NICK "+nick)
37
38	send(conn, "CAP REQ :twitch.tv/tags")       // Enable IRCv3 message tags.
39	send(conn, "CAP REQ :twitch.tv/membership") // Enable JOIN/PART messages.
40	send(conn, "CAP REQ :twitch.tv/commands")   // Enable Twitch commands.
41
42	go stdin(conn)
43	go stdout(conn)
44
45	signals := make(chan os.Signal, 1)
46	signal.Notify(signals, os.Interrupt)
47
48	for {
49		select {
50		case sig := <-signals:
51			fmt.Printf("Signal %q received.\n", sig)
52			return
53		}
54	}
55}
56
57func stdin(conn net.Conn) {
58	scanner := bufio.NewScanner(os.Stdin)
59	for scanner.Scan() {
60		txt := scanner.Text() // No final '\n'.
61		if len(txt) == 0 {
62			continue
63		}
64		if txt[1] == '/' {
65			if err := sendCommand(conn, txt); err != nil {
66				fmt.Printf("Command %q error: %v\n", txt, err)
67			}
68			continue
69		}
70		fmt.Fprintf(conn, "%s\r\n", txt)
71		if err := scanner.Err(); err != nil {
72			fmt.Println("Error from stdin scanner:", err)
73			continue
74		}
75	}
76}
77
78// Print incoming messages from the server to stdout.
79func stdout(conn net.Conn) {
80	scanner := bufio.NewScanner(conn)
81	for scanner.Scan() {
82		msg := scanner.Text()
83		if len(msg) == 0 {
84			continue
85		}
86
87		fmt.Println(msg)
88
89		if strings.HasPrefix(msg, "PING ") {
90			pong(conn, msg)
91			continue
92		}
93
94		//printNonPrivMsgs(msg)
95		if err := scanner.Err(); err != nil {
96			fmt.Println("Error from stdout scanner:", err)
97			continue
98		}
99	}
100}
101
102func pong(conn net.Conn, msg string) {
103	parts := strings.Fields(msg)
104
105	s := fmt.Sprintf("PONG %s", parts[1])
106	fmt.Println(s)
107
108	fmt.Fprintf(conn, "%s\r\n", s)
109}
110
111func printNonPrivMsgs(msg string) {
112	parts := strings.SplitN(msg, " :", 3)
113	if len(parts) < 3 {
114		fmt.Printf("(%d) %#v\n", len(parts), parts)
115	} else {
116		if !strings.Contains(parts[1], " PRIVMSG ") {
117			fmt.Printf("(%d) %#v\n", len(parts), parts)
118		}
119	}
120
121}
122
123func send(conn net.Conn, txt string) {
124	fmt.Println(txt)
125	fmt.Fprintf(conn, "%s\r\n", txt)
126}
127
128func sendCommand(conn net.Conn, command string) error {
129	parts := strings.Fields(command[1:])
130	if len(parts) < 1 {
131		return fmt.Errorf("invalid format for %q\n", command)
132	}
133
134	fmt.Println("Would send command:", command)
135
136	return nil
137}