How do I write a UDP server in Go?

Discovered how simple UDP is. Here is a client and server written in Go. (Error handling omitted for brevity.)

First a server. It listens for UDP packets on port 10001, and prints each message to stdout:

package main
import "net"
import "fmt"
func main() {
  ServerConn, _ := net.ListenUDP("udp", &net.UDPAddr{IP:[]byte{0,0,0,0},Port:10001,Zone:""})
  defer ServerConn.Close()
  buf := make([]byte, 1024)
  for {
    n, addr, _ := ServerConn.ReadFromUDP(buf)
    fmt.Println("Received ", string(buf[0:n]), " from ", addr)
  }
}

Now a client. It sends packets to localhost UDP port 10001, each saying “hello”:

package main
import "net"
func main() {
  Conn, _ := net.DialUDP("udp", nil, &net.UDPAddr{IP:[]byte{127,0,0,1},Port:10001,Zone:""})
  defer Conn.Close()
  Conn.Write([]byte("hello"))
}

By running the server, then running our client repeatedly, we get:

% go run server.go
Received  hello  from  127.0.0.1:55877
Received  hello  from  127.0.0.1:61029
Received  hello  from  127.0.0.1:52922

I wrote this because I felt like it. This post is my own, and not associated with my employer.