Merge pull request #1 from maiorfi/master

JSON WebSocket Push Datasource Plugin

datasources/plugin_json_ws.js

@@ -0,0 +1,86 @@
+(function()
+{
+	var jsonWebSocketDatasource = function(settings, updateCallback)
+	{
+		var self = this;
+		var currentSettings = settings;
+		var ws;
+		
+		var onOpen=function()
+		{
+			console.info("WebSocket(%s) Opened",currentSettings.url);
+		}
+		
+		var onClose=function()
+		{
+			console.info("WebSocket Closed");
+		}
+		
+		var onMessage=function(event)
+		{
+			var data=event.data;
+			
+			console.info("WebSocket received %s",data);
+			
+			var objdata=JSON.parse(data);
+			
+			if(typeof objdata == "object")
+			{
+				updateCallback(objdata);
+			}
+			else
+			{
+				updateCallback(data);
+			}
+			
+		}
+		
+		function createWebSocket()
+		{
+			if(ws) ws.close();
+			
+			var url=currentSettings.url;
+			ws=new WebSocket(url);
+			
+			ws.onopen=onOpen;
+			ws.onclose=onClose;
+			ws.onmessage=onMessage;
+		}
+		
+		createWebSocket();
+
+		this.updateNow = function()
+		{
+			createWebSocket();
+		}
+
+		this.onDispose = function()
+		{
+			ws.close();
+		}
+
+		this.onSettingsChanged = function(newSettings)
+		{
+			currentSettings = newSettings;
+			
+			createWebSocket();
+		}
+	};
+
+	freeboard.loadDatasourcePlugin({
+		type_name  : "JSON WebSocket",
+		display_name : "JSON WebSocket Push Datasource",
+		description : "A push datasource based on browser built-in WebSocket implementation, <em>by Lorenzo Maiorfi - <a href=\"http://www.innovactive.it\">Innovactive Engineering s.r.l.</a></em> You can download a sample dashboard using this datasource <a href=\"https://dl.dropboxusercontent.com/u/7414592/dashboard_demo_1.json\">here</a>",
+		settings   : [
+			{
+				name        : "url",
+				display_name: "URL",
+				type        : "text"
+			}
+		],
+		newInstance: function(settings, newInstanceCallback, updateCallback)
+		{
+			newInstanceCallback( new jsonWebSocketDatasource(settings, updateCallback));
+		}
+	});
+}());