Squeak <> Amber communication using WebSocket (works)

Great, Jacob!

I'll take a look at it later, thanks for sharing :)

2011/10/24 Zenchess <[hidden email]>

http://zenchess.blogspot.com/2011/10/amber-client-to-squeak-image.html


 I have had success testing amber to squeak (and back) communication
using websocket.  This is after hours of failing to get socket.io and
nowJs to work with amber server.
WebSocket is a new protocol in HTML 5 and is supported on modern
browsers.  The channel is always open so you do not have to constantly
poll the server for updates.  The channel is also
bi-directional.

 Here is a post I made describing how I got it to work with WebClient
for squeak and stock amber.  Please note the pastebin link at top -
the code didn't format correctly in blogger.

There are some quirks such as having to send the "send:" message to
websocket at the same time as the other code (or it doesnt work).  But
once you do that you can send messages to the WebSocket object at your
leisure.

 Right now I am using squeak with Webclient but pharo 1.3 can run
Websockets through swazoo2 so you could use that as well I'm
assuming.

Happy smalltalking!
-Jacob Wagner

--
Bernat Romagosa.

I think webclient websockets don't work in pharo for some reason.

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

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

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/"

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.

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' on: [:socket|    "callback gives you the handle to the socket. you can store that for later"                         

        socket on: 'NewsPosted' do: [ :eventInfo | "specify the events you want to distribute here"

socket emit: 'RemoveCard' withData: eventInfo. "Here I just recast it"

].

On the client 

Insert into the head of your html: 

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

Establish the connection & event-handling

ClientController>>establishConnection

self socket: (io connect: 'http://your-url-and-server:port:').

self socket on: 'NewsPosted' do: [:data | alert value: data]. "You can specify all the events you want to handle this way or write a method for it"

"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)] .

And send data:

ClientController>>postNews: jsonData

self socket emit: 'NewsPosted' with: jsonData.

Maybe I can extract the chat I wrote later, but that is not a priority right now for me.

On Wed, Oct 26, 2011 at 10:12 AM, Bernat Romagosa <[hidden email]> wrote:

I have the same impression :)

I'm trying to get a little multiclient chat demo working based on laci's experiments, I think this would make an interesting example...

Cheers,

2011/10/26 Zenchess <[hidden email]>

I think webclient websockets don't work in pharo for some reason.

--
Bernat Romagosa.