Telnet server demo (for your Go telnet lib)

telnet_example/mud.go

@@ -0,0 +1,76 @@
+/*-----------------------------------------------------------------
+  Telnet Server example for golang telnet:
+
+  https://github.com/ziutek/telnet
+
+  (altered/modified/extended from original client example)
+  by mahan on 20130606  
+-----------------------------------------------------------------*/
+package main
+
+import (
+  "fmt"
+  "github.com/ziutek/telnet"
+  "log"
+  "time"
+  "net"
+  "strings"
+)
+
+const timeout = 10 * time.Second
+
+func checkErr(err error) {
+  if err != nil {
+    log.Fatalln("Error:", err)
+  }
+}
+
+//This is where you handle the flow of incoming connections.
+func handleConnection(c net.Conn) {
+  conn, _ := telnet.NewConn(c)
+  checkErr(c.SetDeadline(time.Now().Add(timeout)))
+
+  fmt.Println("------------------------ Handle Connection --------------------------")
+  sendln(conn, ":D (LolMUd 6.53) \x1b[31;1mDangereous Dragons\x1b[0m and stuff be here.\n")
+  send(conn, "What is your name, traveller? ")
+  username, err := input(conn)
+  checkErr(err)
+  sendln(conn, "")
+  sendln(conn, fmt.Sprintf("Hello there, %s. Sorry but I'll have to disconnect you until the game is ready.", username))
+  fmt.Println("User connected: ", username)
+  conn.Close()
+  fmt.Println("Connection for", username, "disconnected.")
+}
+
+//Get a line of text from the user
+func input(t *telnet.Conn) (string, error) {
+  username, err := t.ReadString('\r')
+  username = strings.Trim(username, "\r\f")
+  return username, err
+}
+
+//Send a row of text to the client (without ending the line)
+func send(t *telnet.Conn, s string) {
+  buf := make([]byte, len(s))
+  copy(buf, s)
+  _, err := t.Write(buf)
+  checkErr(err)
+}
+
+//Send a row of text to the client + EOL
+func sendln(t *telnet.Conn, s string) {
+  s += "\n"
+  send(t, s)
+}
+
+//Generic TCP-Server startup
+func main() {
+  fmt.Println("Mud started. Write 'telnet 127.0.0.1 4000' in another terminal to connect.")
+  ln, err := net.Listen("tcp", ":4000")
+  checkErr(err)
+  for {
+    conn, err := ln.Accept()
+    checkErr(err)
+    go handleConnection(conn)
+  }
+}