node-red/nodes/io/32-udp.js

/**
 * Copyright 2013 IBM Corp.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 **/

var RED = require("../../red/red");
var dgram = require('dgram');

// The Input Node
function UDPin(n) {
	RED.nodes.createNode(this,n);
	this.group = n.group;
	this.port = n.port;
	this.host = n.host || null;
	this.datatype = n.datatype;
	this.iface = n.iface || null;
	this.multicast = n.multicast;
	var node = this;

	var server = dgram.createSocket('udp4');

	server.on("error", function (err) {
		console.log("udp listener error:\n" + err.stack);
		server.close();
	});

	server.on('message', function (message, remote) {
		var msg;
		if (node.datatype =="base64") { msg = { payload:message.toString('base64'), fromip:remote.address+':'+remote.port }; }
		else if (node.datatype =="utf8") { msg = { payload:message.toString('utf8'), fromip:remote.address+':'+remote.port }; }
		else { msg = { payload:message, fromip:remote.address+':'+remote.port }; }
		node.send(msg);
	});

	server.on('listening', function () {
		var address = server.address();
		node.log('udp listener at ' + address.address + ":" + address.port);
		if (node.multicast == "true") {
			server.setBroadcast(true)
			server.setMulticastTTL(128);
			server.addMembership(node.group,node.iface);
			node.log("udp multicast group "+node.group);
		}
	});

	node.on("close", function() {
		try {
			server.close();
			node.log('udp listener stopped');
		}
		catch (err) { console.log(err); }
	});

	server.bind(node.port,node.host);
}
RED.nodes.registerType("udp in",UDPin);


// The Output Node
function UDPout(n) {
	RED.nodes.createNode(this,n);
	//this.group = n.group;
	this.port = n.port;
	this.base64 = n.base64;
	this.addr = n.addr;
	this.iface = n.iface || null;
	this.multicast = n.multicast;
	var node = this;

	var sock = dgram.createSocket('udp4');  // only use ipv4 for now
	sock.bind(node.port); 			// have to bind before you can enable broadcast...
	if (this.multicast != "false") {
		sock.setBroadcast(true);		// turn on broadcast
		if (this.multicast == "multi") {
			sock.setMulticastTTL(128);
			sock.addMembership(node.addr,node.iface);	// Add to the multicast group
			node.log('udp multicast ready : '+node.addr+":"+node.port);
		}
		else node.log('udp broadcast ready : '+node.addr+":"+node.port);
	}
	else node.log('udp ready : '+node.addr+":"+node.port);

	node.on("input", function(msg) {
		if (msg.payload != null) {
			//console.log("UDP:",msg.payload);
			var message;
			if (node.base64) { message = new Buffer(b64string, 'base64'); }
			else { message = new Buffer(""+msg.payload); }
			console.log("UDP send :",node.addr,node.port);
			sock.send(message, 0, message.length, node.port, node.addr, function(err, bytes) {
				if (err) node.error("udp : "+err);
			});
		}
	});

	node.on("close", function() {
		try {
			sock.close();
			node.log('udp output stopped');
		}
		catch (err) { console.log(err); }
	});
}
RED.nodes.registerType("udp out",UDPout);