Merge pull request #924 from QNimbus/client-only-pr

Added clientonly script

CHANGELOG.md

@@ -5,9 +5,13 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ## [2.1.3] - Unreleased
 
 ### Changed
+
 ### Added
+- Add `clientonly` script to start only the electron client for a remote server.
 - Add symbol and color properties of event when `CALENDAR_EVENTS` notification is broadcasted from `default/calendar` module.
+
 ### Updated
+
 ### Fixed
 
 - Fixed issue with incorrect allignment of analog clock when displayed in the center column of the MM

README.md

@@ -48,6 +48,11 @@ bash -c "$(curl -sL https://raw.githubusercontent.com/MichMich/MagicMirror/maste
 ### Server Only
 In some cases, you want to start the application without an actual app window. In this case, you can start MagicMirror² in server only mode by manually running `node serveronly` or using Docker. This will start the server, after which you can open the application in your browser of choice. Detailed description below.
 
+### Client Only
+When you have a server running remotely and want to connect a standalone client to this instance, you can manually run `node clientonly --address 192.168.1.5 --port 8080`. (Specify the ip address and port number of the server)
+
+**Important:** Make sure that you whitelist the interface/ip in the server config where you want the client to connect to, otherwise it will not be allowed to connect to the server
+
 #### Docker
 
 MagicMirror² in server only mode can be deployed using [Docker](https://docker.com). After a successful [Docker installation](https://docs.docker.com/engine/installation/) you just need to execute the following command in the shell:

clientonly/index.js

@@ -0,0 +1,97 @@
+/* jshint esversion: 6 */
+
+"use strict";
+
+// Use seperate scope to prevent global scope pollution
+(function () {
+	var config = {};
+
+	// Helper function to get server address/hostname from either the commandline or env
+	function getServerAddress() {
+		// Helper function to get command line parameters
+		// Assumes that a cmdline parameter is defined with `--key [value]`
+		function getCommandLineParameter(key, defaultValue = undefined) {
+			var index = process.argv.indexOf(`--${key}`);
+			var value = index > -1 ? process.argv[index + 1] : undefined;
+			return value !== undefined ? String(value) : defaultValue;
+		}
+
+		// Prefer command line arguments over environment variables
+		["address", "port"].forEach((key) => {
+			config[key] = getCommandLineParameter(key, process.env[key.toUpperCase()]);
+		})
+	}
+
+	function getServerConfig(url) {
+		// Return new pending promise
+		return new Promise((resolve, reject) => {
+			// Select http or https module, depending on reqested url
+			const lib = url.startsWith("https") ? require("https") : require("http");
+			const request = lib.get(url, (response) => {
+				var configData = "";
+
+				// Gather incomming data
+				response.on("data", function(chunk) {
+					configData += chunk;
+				});
+				// Resolve promise at the end of the HTTP/HTTPS stream
+				response.on("end", function() {
+					resolve(JSON.parse(configData));
+				});
+			});
+
+			request.on("error", function(error) {
+				reject(new Error(`Unable to read config from server (${url} (${error.message}`));
+			});
+		})
+	};
+
+	function fail(message, code = 1) {
+		if (message !== undefined && typeof message === "string") {
+			console.log(message);
+		} else {
+			console.log("Usage: 'node clientonly --address 192.168.1.10 --port 8080'");
+		}
+		process.exit(code);
+	}
+
+	getServerAddress();
+
+	(config.address && config.port) || fail();
+
+	// Only start the client if a non-local server was provided
+	if (["localhost", "127.0.0.1", "::1", "::ffff:127.0.0.1", undefined].indexOf(config.address) === -1) {
+		getServerConfig(`http://${config.address}:${config.port}/config/`)
+			.then(function (config) {
+				// Pass along the server config via an environment variable
+				var env = Object.create(process.env);
+				var options = { env: env };
+				config.address = config.address;
+				config.port = config.port;
+				env.config = JSON.stringify(config);
+
+				// Spawn electron application
+				const electron = require("electron");
+				const child = require("child_process").spawn(electron, ["js/electron.js"], options);
+
+				// Pipe all child process output to current stdout
+				child.stdout.on("data", function (buf) {
+					process.stdout.write(`Client: ${buf}`);
+				});
+
+				// Pipe all child process errors to current stderr
+				child.stderr.on("data", function (buf) {
+					process.stderr.write(`Client: ${buf}`);
+				});
+
+				child.on("error", function (err) {
+					process.stdout.write(`Client: ${err}`);
+				});
+			})
+			.catch(function (reason) {
+				fail(`Unable to connect to server: (${reason})`);
+			});
+	} else {
+		fail();
+	}
+}());

config/config.js.sample

@@ -9,6 +9,7 @@
  */
 
 var config = {
+	address: "localhost",
 	port: 8080,
 	ipWhitelist: ["127.0.0.1", "::ffff:127.0.0.1", "::1"], // Set [] to allow all IP addresses
 	                                                       // or add a specific IPv4 of 192.168.1.5 :

js/defaults.js

@@ -8,10 +8,12 @@
  */
 
 var port = 8080;
+var address = "localhost";
 if (typeof(mmPort) !== "undefined") {
 	port = mmPort;
 }
 var defaults = {
+	address: address,
 	port: port,
 	kioskmode: false,
 	electronOptions: {},

js/electron.js

@@ -6,7 +6,7 @@ const electron = require("electron");
 const core = require(__dirname + "/app.js");
 
 // Config
-var config = {};
+var config = process.env.config ? JSON.parse(process.env.config) : {};
 // Module to control application life.
 const app = electron.app;
 // Module to create native browser window.
@@ -47,7 +47,7 @@ function createWindow() {
 
 	// and load the index.html of the app.
 	//mainWindow.loadURL('file://' + __dirname + '../../index.html');
-	mainWindow.loadURL("http://localhost:" + config.port);
+	mainWindow.loadURL(`http://${config.address}:${config.port}`);
 
 	// Open the DevTools if run with "npm start dev"
 	if (process.argv.includes("dev")) {
@@ -96,8 +96,10 @@ app.on("activate", function() {
 	}
 });
 
-// Start the core application.
+// Start the core application if server is run on localhost
 // This starts all node helpers and starts the webserver.
-core.start(function(c) {
+if (["localhost", "127.0.0.1", "::1", "::ffff:127.0.0.1", undefined].indexOf(config.address) > -1) {
+	core.start(function (c) {
 		config = c;
-});
+	});
+}

js/server.js

@@ -52,6 +52,10 @@ var Server = function(config, callback) {
 		res.send(global.version);
 	});
 
+	app.get("/config", function(req,res) {
+		res.send(config);
+	});
+
 	app.get("/", function(req, res) {
 		var html = fs.readFileSync(path.resolve(global.root_path + "/index.html"), {encoding: "utf8"});
 		html = html.replace("#VERSION#", global.version);