Skip to content
This repository

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP

Lightweight RPC support for the ws WebSocket server

branch: master

0.0.8

latest commit 90a30ed7ac
Juraj Vitko authored May 27, 2013
Octocat-spinner-32 example-simple simple express 3 example May 09, 2013
Octocat-spinner-32 example update February 27, 2012
Octocat-spinner-32 lib 0.0.6 March 13, 2013
Octocat-spinner-32 public 0.0.8 May 27, 2013
Octocat-spinner-32 .npmignore update February 27, 2012
Octocat-spinner-32 LICENSE update February 26, 2012
Octocat-spinner-32 README.md 0.0.6 March 13, 2013
Octocat-spinner-32 package.json 0.0.8 May 27, 2013
Octocat-spinner-32 scrap.txt update February 27, 2012
README.md

ws-rpc: lightweight RPC support for the ws WebSocket server

News

0.0.6 - Upon disconnection, client now errors (cleans) all pending (client-initiated) callbacks.

Important

For increased reliability, it is suggested to use the WebSocket protocol over encrypted connections only. Some proxy servers handle the unencrypted form of the protocol in a way which prevents it from operation. This is being addressed by "masking" in newer versions of the protocol, however too many older versions are already in the wild. See the second code example on this page on how to configure HTTPS support in your Node.

Server

Install dependencies:

npm install express
npm install ws
npm install ws-rpc
npm install ws-flash-client
npm install policyfile

Example with Express, ws, and the Flash client shim support (see below for HTTPS):

Notes:

  • args stands for multiple arguments, e.g. arg1, arg2, arg3
  • messages with callbacks can only be used when messaging a single client
var prod = process.env.NODE_ENV === 'production';
var app = require('express').createServer();
var ws = require('ws-rpc').extend(require('ws'));
var wss = new ws.Server({ server: app });
var wsflash = require('ws-flash-client');
require('policyfile').createServer().listen(prod ? 843 : 10843, app);

app.configure(function() {
    // configure other stuff like express globals, jade, stylus, etc.
    // ...

    // configure the ws-rpc middleware:
    app.use(wss.middleware(express));

    // configure the ws-flash-client middleware:
    app.use(wsflash.middleware(express));

    // static file handling must come afterwards:
    app.use(express.static(pub));

    // bind node to a port
    app.listen(prod ? 80 : 1234);
});

// create/get a named room (channel)
var myRoom = wss.room('myRoom');

// handle a new client connection
wss.on('connect', function(client) {

    // add client to a room
    myRoom.add(client);

    // message the client
    client.message('some message', args);

    // message the client with callback
    client.message('some message', args, function(err, args) {
        if(err)
            // ...
    });

    // Note:
    // you can hook your listener actions on every client separately, but if you 
    // have the same handler for every client, you should consider doing it the way
    // below*, as with large number of clients, that will save you a lot of resources.

    // handle message from a client without a callback
    client.on('some message', function(args) {

        // ...
    });

    // handle message from a client with a callback
    client.on('some message', function(args, cb) {

        // ...

        // call the callback (should use node convention but not mandatory)
        cb(null, 'ok');
    });

});

// *handle message from a client without a callback
wss.on('some message', function(client, args) {

    // ...
});

// *handle message from a client with a callback
wss.on('some message', function(client, args, cb) {

    // ...

    // call the callback (should use node convention but not mandatory)
    cb(null, 'ok');
});

// handle client disconnection
wss.on('disconnect', function(client) {

    //myRoom.remove(client); <- not necessary, this is done automatically

    // example: broadcast to all client's rooms
    for(id in client.rooms)
        client.rooms[id].message('some message', args);
});

// message all clients connected to the server
wss.message('some message', args);

// message all clients in a room
myRoom.message('some message', args);

// and don't forget this if you don't want your Node to crash on an error:
// if the error comes from a client, the client is passed as second parameter
wss.on('error', function(e, client) {
    console.log(client ? 'client' : 'server', e);
});

Binary messages are not handled by the RPC extension, so you can handle them separately using the classic ws API.

The above example, but with HTTP + HTTPS support

For completeness, here's a guide on how to get a free 90-day SSL certificate:

1) Make a subdirectory in your project folder, e.g.: mkdir https

2) Create a text file in that directory, e.g.: www.yourdomain.com.txt, with the following contents (C= is the ISO 3166-1 Alpha-2 code of your country)

[ req ]
distinguished_name=req_distinguished_name
prompt=no

[ req_distinguished_name ]
C=US
ST=State or County or Shire
L=City
O=Company Name
CN=yourdomain.com
emailAddress=support@yourdomain.com

3) Execute the following commands (the second command is to remove password from your secret-key file):

openssl genrsa -des3 -out www.yourdomain.com.key.sec 2048
openssl rsa -in www.yourdomain.com.key.sec -out www.yourdomain.com.key
rm www.yourdomain.com.key.sec
openssl req -new -config www.yourdomain.com.txt -key www.yourdomain.com.key -out www.yourdomain.com.csr

4) Use the CSR file to request a certificate from a recognized issuer. (You can get a free 90-day free certificate from here. I'm not affiliated in any way with that site, but it worked for me. UPDATE: these certificates display a warning on Firefox: "Error code: sec_error_unknown_issuer".)

5) After verification through your domain's contact email address, you will obtain a CRT file from the issuer. Place it along with the KEY file you generated above in the https directory.

Then configure your server as follows:

var prod = process.env.NODE_ENV === 'production';
var app = require('express').createServer();
var ws = require('ws-rpc').extend(require('ws'));
var wsflash = require('ws-flash-client');
require('policyfile').createServer().listen(prod ? 843 : 10843, app);

var httpsOptions = {
    key: fs.readFileSync('https/www.yourdomain.com.key'),
    cert: fs.readFileSync('https/www.yourdomain.com.crt')
};

var httpServer = http.createServer(app.handle.bind(app)).listen(port);
var httpsServer = https.createServer(httpsOptions, app.handle.bind(app))
    .listen(httpsPort);

var wss = new ws.Server({ server: new ws.ServerHub([ httpServer, httpsServer ]) });

app.configure(function() {
    // continue as in the above example
    // ...

Browser

In your HTML page (JADE syntax shown):

!!! 5
html
    head
        meta(http-equiv='X-UA-Compatible', content='IE=Edge,chrome=1')
        //if lt IE 8
            script(src='http://cdnjs.cloudflare.com/ajax/libs/json2/20110223/json2.min.js')
        script(src='http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js')
        script(src='/ws-rpc-client.min.js')
        script(src='/ws-flash.min.js')
        script(src='/myclientcode.js')
    body
        #msg

Complete example of the myclientcode.js with the Flash client shim support (for full usage and options please see ws-flash-client):

$(function() {

    $.wsFlashClientInit({}, function(err) {
        if(err)
            return log('no websocket support');

        var WebSocketRPC = InitWebSocketRPC(WebSocket);

        // create the client (will use WebSocket object on the background)
        // param1: url
        // param2 (optional): protocols, see http://dev.w3.org/html5/websockets/#websocket
        // param3 (optional): connection timeout in ms (default 4s), use -1 to disable auto-reconnect
        // param4 (optional): reconnection wait timeout in ms (default 1s)
        var ws = new WebSocketRPC('ws://' + window.location.host + '/');

        // handle a message from the server
        ws.on('some message', function(args) {

            // ...
        });

        // handle a message from the server with a callback
        ws.on('some message', function(args, cb) {

            // ...

            cb(null, 'hello from client');

            // or, in the case of an error:

            cb(new Error('some problem'));
        });

        // message the server
        ws.message('some message', args);

        // message the server with a callback
        ws.message('some message', args, function(err, args) {
            if(err)
                // ...
        });

        // disconnect from the server
        // param1 (optional): disable automatic reconnection
        ws.disconnect(true);

        // connected event
        ws.on('open', function() {
            log('connected');

            // access the WebSocket if needed:
            //ws.socket ... <- will be null when disconnected, and then a new one created
        });

        // disconnected event
        ws.on('close', function() {
            log('disconnected');
        });

        // error event
        ws.on('error', function(e) {
            log(e.stack || e);
        });
    });

    // just an example
    function log(s) {
        var m = $('#msg');
        m.text(m.text()  + '\n' + s);
    }
});

Usage without ws-flash-client:

var WebSocketRPC = InitWebSocketRPC(WebSocket);
var ws = new WebSocketRPC('ws://' + window.location.host + '/');

// ..and the same operations as above..

Using the WebSocket client from Node.js

var ws = require('ws-rpc').extend(require('ws'));
var wsc = new ws.RPCWebSocket('ws://127.0.0.1:1144/');

wsc.on('message 1', function(arg1, arg2, cb) {
    log('message 1: ' + arg1 + ', ' + arg2);
    cb(null, 'message1 response from client', 'arg2');
});

// etc.

Example

Find the example app here, or installed in node_modules/ws-rpc/example.

cd example
npm install
node testws

Then load http://localhost:1144/ in your browsers, and/or open another console and

cd example
node testws-server-client

Tested with

├─┬ express@2.5.8 
│ ├─┬ connect@1.8.5 
│ │ └── formidable@1.0.9 
│ ├── mime@1.2.4 
│ ├── mkdirp@0.3.0 
│ └── qs@0.4.2 
├─┬ jade@0.20.3 
│ ├── commander@0.5.2 
│ └── mkdirp@0.3.0 
├── nib@0.3.2 
├── policyfile@0.0.5 
├─┬ stylus@0.24.0 
│ ├── cssom@0.2.2 
│ ├── debug@0.5.0 
│ ├── growl@1.4.1 
│ └── mkdirp@0.3.0 
├─┬ ws@0.4.7 
│ ├── commander@0.5.0 
│ └── options@0.0.2 
├── ws-flash-client@0.0.2
└── ws-rpc@0.0.2

Tested on

  • Google Chrome 17 Mac, 16, 17 Win
  • Firefox 7 Mac, 10 Win
  • Internet Explorer 6, 7, 8, 9 on Win XP and Win 7 (Flash)
  • Safari 5.1 Win, 5 Mac
  • Opera 9.8 Win (Flash)
  • Chrome Beta on Android 4.0, Galaxy Nexus
  • Mobile Safari on iOS 5.0.1, iPhone 3GS

License

New BSD License.

Something went wrong with that request. Please try again.