Dart Force Framework


A realtime web framework for dart.

With this framework communication between client and server becomes easy, without any boilerplate code.

Look at our wiki for more info or this info below.


Client side

Import the client side library for dart force.

import 'package:force/force_browser.dart';

First create a client.

 ForceClient forceClient = new ForceClient();

Listen on the connection, when it is established.

 forceClient.onConnected.listen((e) {

Listen on the connection, when it is been broken.

 forceClient.onDisconnected.listen((e) {

Listen on messages with the request of text.

 forceClient.on("text", (e, sender) {

You can also send messages to the server.

forceClient.send('text', data);

When you are in the need to reply on a message, you can use the 'reply' method of sender.

forceClient.on("text", (e, sender) {
	sender.reply("received", ok_data);
Server Side

Import Serverside code for dart force.

import 'package:force/force_serverside.dart';

Instantiate a forceserver.

ForceServer fs = new ForceServer( port: 9223, startPage: 'start.html' );

Other optional properties that are possible on ForceServer:

wsPath: is the websocket path of the server host: is the domain name of your application, by default to localhost port: is the adres port of the application buildPath: is the build path of the application by default this is ../build/web/ startPage: the startpage of the application, the html name that the app needs to use as default root page staticDir: is the public directory where you can put your stylesheets and images

Listen on messages of type text and react upon that.

fs.on('text', (e, sendable) { 
    var json = e.json;
    var line = json['line'];
    sendable.send('text', { 'line': line });

You can also serve files from the server part.

fs.start().then((_) {
    fs.serve("/client.dart").listen((request) { 
      fs.serveFile("../web/client.dart", request);

You can listen when a new Socket connection is been created.

fs.onSocket.listen((SocketEvent se) {
	// socket event

Other features

Profile info & client to client communication

Adding profile data on a connection, this will make it easy to send a message to a certain profile group or sending messages to an individual, without knowing his websocket id.

On the client you can set the current browser user his profile data as follow.

 var profileInfo = { 'name' : chatName};

On the server you can send something to a profile or a profile group by the following method in sendable.

sendable.sendToProfile('name', name, 'private', message);

You can also listen to profileChanges by using the following method on the forceServer.

fs.onProfileChanged().listen((e) => print("$e"));

Now you can send directly from the client to another client, the server notice the message type and forward it directly to the corresponding client. No coding on server required todo this!

Just add the following code in your client side code.

forceClient.sendToProfile(key, value, request, data);
Long polling

You can easily use long polling as follow!

forceClient = new ForceClient(usePolling: true, heartbeat: 200);

Serverside Classes with Receiver method annotations

On the server you can use @Receiver on a method to define that this is a receiver method. It is the same as forceServer.on("play", (e, sendable) {


void onGamePlay(ForceMessageEvent vme, Sender sender) {

You can register this class with the register method of a ForceServer object.

forceServer.register(new GameReceiver());

You can also annotate a class with the @Receivable annotation, so the system can pick up this class and automatically register these classes.

Dart Force mvc access

You have access to the force mvc webserver if you do the following:

forceServer.server.on(url, controllerHandler, method: 'GET');

You can now add the annotation @Authentication to a receiver class.

You can also do the following.

forceServer.on("examplerequest", (e, sendable) {
   // do something
}, roles: ["ADMIN", "BASIC"]); 

An authentication in force is following a strategy. You can set a strategy by extending the class SecurityStrategy.

class SessionStrategy extends SecurityStrategy {
  bool checkAuthorization(HttpRequest req) {
    HttpSession session = req.session;
    return (session["user"]!=null);
  Uri getRedirectUri(HttpRequest req) {
    var referer = req.uri.toString();
    return Uri.parse("/login/?referer=$referer");

And then add this strategy to the webserver.

forceServer.server.strategy = new SessionStrategy();

When you are not authorized, the system sends the following message back: "unauthorized" with the data you send over the system. So you can also listen to the message "unauthorized" in your client, then you can inform the user he need to login.


You can easily boostrap logging.


Other Annotations

In the @Receivable classes you can also use:

@NewConnection : when a new socket connection is established

void connection(socketId, Socket socket) {
	print("new connection created for $socketId");

@ClosedConnection : when a socket connection is been closed

void closedConnection(socketId, Socket socket) {
	print("connection closed for $socketId");

Server 2 Server Communication

With the implementation of ServerSockets it is possible to use a ForceClient on the server.

This allows you todo server 2 server communication.

On the Force Server you implements:

Connector connector = new ServerSocketConnector();


On the other server where you want to sent messages to the Force Server you use:

ForceClient fc = new ForceClient();

fc.on("update", (fme, sender) {
      print("todo: ${fme.json["todo"]}");

Under the hood it will establish a connection to the server socket.

Development trick

Following the next steps will make it easier for you to develop, this allows you to adapt clientside files and immidiatly see results with doing a pub build.

pub serve web --hostname --port 7777 &&
export DART_PUB_SERVE="http://localhost:7777" &&
pub run bin/server.dart


You can now easily run your Force apps on a Google App Engine infrastructure by the following code! The rest is the same as a normal dart force app.

  ForceServer forceServer = new ForceServer();
  runAppEngine(forceServer.requestHandler).then((_) {
      // Server running. and you can do all the stuff you want!

You don't need to start ForceServer anymore, start of the server will be done by AppEngine!

More info about GAE overall

Notes to Contributors

Fork Dart Force

If you'd like to contribute back to the core, you can fork this repository and send us a pull request, when it is ready.

If you are new to Git or GitHub, please read this guide first.


Follow us on twitter https://twitter.com/usethedartforce


Follow us on google+

or join our G+ Community

Screencast tutorial

Screencast todo tutorial about the dart force realtime functionality on youtube

Join our discussion group

Google group


Links to some examples that I made with this framework.

chat - source code

polymer example - source code