Nodejs implementation of a simple udp broadcast server client
- 2020-03-30 03:58:57
- OfStack
Nodejs sending udp broadcast is quite simple, we first write a server to receive broadcast data, the code is as follows:
var dgram = require("dgram");
var server = dgram.createSocket("udp4");
server.on("error", function (err) {
console.log("server error:n" + err.stack);
server.close();
});
server.on("message", function (msg, rinfo) {
console.log("server got: " + msg + " from " +
rinfo.address + ":" + rinfo.port);
});
server.on("listening", function () {
var address = server.address();
console.log("server listening " +
address.address + ":" + address.port);
});
server.bind(41234);
Then write a client program, send broadcast message, the code is as follows:
var dgram = require("dgram");
var socket = dgram.createSocket("udp4");
socket.bind(function () {
socket.setBroadcast(true);
});
var message = new Buffer("Hi");
socket.send(message, 0, message.length, 41234, '255.255.255.255', function(err, bytes) {
socket.close();
});
Note that socket.setbroadcast (true); It can only be called after successfully binding the socket, otherwise it will report an Error: setBroadcast EBADF Error.
It is quite simple for the client to send the broadcast, and it is OK to set the data and port that need to be sent.