Getting started with Amber and socket.io

Here's a rough-cut of using socket.io with Amber:

1. Install Node.js in the appropiate way for your plattform.

2. Install socket.io using npm. If that fails, download it manually and set your node module path like so:

    export NODE_PATH=$NODE_PATH:/your/path/to/socket.io/
   

3. Create a server-script in node.js for example by subclassing FileServer and create a start-method:

    YourFileServer>>start
    	(httpServer := http createServer: [:request :response |
    	 	self handleRequest: request respondTo: response]) listen: self port.
    	self setupSocketIO.`
   

4. Create a socket setup method:

    YourFileServer>>setupSocketIO
        | iopath |
        "Require with just the name did not work for me, I had to specify the path manually"
        iopath := '/Network/Servers/Eskridge/Projects/Amber/amber/.node_modules/socket.io/index'.
   
        "Mount socket.io to the httpServer created in #start"
        io := (self require: iopath) listen: httpServer.
   
        "Define the behaviour of the socket"
        io sockets on: 'connection' do: [:socket|    
            "socket gives you the handle to the socket. you can store that for later"   
                      
            "specify the events you want to distribute here"
            socket on: 'NewsPosted' do: [ :eventInfo | 
                "Here I just recast it"
                socket emit: 'NewsPosted' withData: eventInfo. 
            ].
        ].
   

5. On the client Insert into the head of your html:

    <script src="/socket.io/socket.io.js"></script>
   

6. Establish the connection & event-handling

    ClientController>>establishConnection
    	self socket: (io connect: 'http://your-url-and-server:port').
   
            "You can specify all the events you want to handle this way or write a method for it"
        	self socket on: 'NewsPosted' do: [:data | window alert: data].
   
    "convinience method for the specification of events to handle"
    ClientController>>on: anEvent do: anUnaryBlock
            self socket on: anEvent do: [:eventInfoString | 
                anUnaryBlock value: (JSON parse: eventInfoString) ].
   

7. And send data:

    ClientController>>postNews: jsonData
        self socket emit: 'NewsPosted' with: jsonData.