1 files changed, 93 insertions, 0 deletions
diff --git a/dgbuilder/public/red/comms.js b/dgbuilder/public/red/comms.js
new file mode 100644
index 00000000..64912476
--- /dev/null
+++ b/dgbuilder/public/red/comms.js
@@ -0,0 +1,93 @@
+/**
+ * Copyright 2014 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.
+ **/
+ 
+RED.comms = (function() {
+    
+    var errornotification = null;
+    var subscriptions = {};
+    var ws;
+    function connectWS() {
+        var path = location.hostname+":"+location.port+document.location.pathname;
+        path = path+(path.slice(-1) == "/"?"":"/")+"comms";
+        path = "ws"+(document.location.protocol=="https:"?"s":"")+"://"+path;
+        ws = new WebSocket(path);
+        ws.onopen = function() {
+            if (errornotification) {
+                errornotification.close();
+                errornotification = null;
+            }
+            for (var t in subscriptions) {
+                if (subscriptions.hasOwnProperty(t)) {
+                    ws.send(JSON.stringify({subscribe:t}));
+                }
+            }
+        }
+        ws.onmessage = function(event) {
+            var msg = JSON.parse(event.data);
+            if (msg.topic) {
+                for (var t in subscriptions) {
+                    if (subscriptions.hasOwnProperty(t)) {
+                        var re = new RegExp("^"+t.replace(/([\[\]\?\(\)\\\\$\^\*\.|])/g,"\\$1").replace(/\+/g,"[^/]+").replace(/\/#$/,"(\/.*)?")+"$");
+                        if (re.test(msg.topic)) {
+                            var subscribers = subscriptions[t];
+                            if (subscribers) {
+                                for (var i=0;i<subscribers.length;i++) {
+                                    subscribers[i](msg.topic,msg.data);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        };
+        ws.onclose = function() {
+            if (errornotification == null) {
+                errornotification = RED.notify("<b>Error</b>: Lost connection to server","error",true);
+            }
+            setTimeout(connectWS,1000);
+        }
+    }
+    
+    function subscribe(topic,callback) {
+        if (subscriptions[topic] == null) {
+            subscriptions[topic] = [];
+        }
+        subscriptions[topic].push(callback);
+        if (ws && ws.readyState == 1) {
+            ws.send(JSON.stringify({subscribe:topic}));
+        }
+    }
+    
+    function unsubscribe(topic,callback) {
+        if (subscriptions.topic) {
+            for (var i=0;i<subscriptions.topic.length;i++) {
+                if (subscriptions.topic[i] === callback) {
+                    subscriptions.topic.splice(i,1);
+                    break;
+                }
+            }
+            if (subscriptions.topic.length === 0) {
+                delete subscriptions.topic;
+            }
+        }
+    }
+    
+    return {
+        connect: connectWS,
+        subscribe: subscribe,
+        unsubscribe:unsubscribe
+    }
+})();