Add discovery (mdns) and SNMP nodes

io/mdns/mdns.js

@@ -0,0 +1,51 @@
+/**
+ * Copyright 2015 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.
+ **/
+
+module.exports = function(RED) {
+    "use strict";
+
+    function MdnsNode(n) {
+        var mdns = require('mdns');
+        if (process.platform === "linux") {
+            RED.log.info("You may ignore the warning about Bonjour compatability.");
+        }
+        RED.nodes.createNode(this, n);
+        this.topic = n.topic || "";
+        this.service = n.service;
+        var browser = mdns.createBrowser(this.service);
+        var node = this;
+
+        browser.on('serviceUp', function (service) {
+            if (RED.settings.verbose) { node.log("here : " + service.name); }
+            service.state = true;
+            var msg = {topic: node.topic, payload: service};
+            node.send(msg);
+        });
+        browser.on('serviceDown', function (service) {
+            if (RED.settings.verbose) { node.log("away : " + service.name); }
+            service.state = false;
+            var msg = {topic: node.topic, payload: service};
+            node.send(msg);
+        });
+        browser.start();
+
+        node.on("close", function () {
+            browser.stop();
+        });
+    }
+
+    RED.nodes.registerType("discovery", MdnsNode);
+}