Yet another WebSocket implementation for Common Lisp. This one aspires to be RFC6455 compliant.
I wanted a modern websocket implementation with minimal dependencies that I could run cross platform. My primary goal is to use an HTML5 browser for the GUI of my Common Lisp applications.
I tried the other WebSocket related projects, but none seemed suitable. IOLib is unfortunately not cross platform.
This is a pre-beta release - not fully featured but certainly good enough for demos and prototypes. Feedback and contributions through GitHub are welcome.
The code comes with a BSD-style license so you can basically do with it whatever you want.
Credit to Simon David Pratt who wrote a draft implementation in 2010 called cl-websocket at https://github.com/spratt/cl-websocket , but this is a rewrite for RFC6455.
Based on the HTML5 WebSocket protocol as defined in RFC6455. The intention is that this library should be easy to use in conjunction with any TCP socket implementation or web server framework.
There is a sample that uses usocket to provide a very simple, cross platform, single-threaded socket server. It's sufficient to allow you to connect with an HTML5 browser and run an echo server or, more interestingy a REPL in your browser!
I intentionally and explicitly do not support earlier draft versions of WebSockets - the library landscape is already littered with these, and we need to move on.
The easist place to start is the sample code. Load it up using your favourite Quicklisp enabled Lisp environment:
> (ql:quickload "cl-websocket-sample")
> (cl-websocket-sample:echo-server)
Then point your HTML5 web browser (probably Chrome?) at the sample.html file on disk. Press the connect button, now anything you type and Send should be echo'd back.
You might also like to try the REPL sample
(cl-websocket-sample:repl-server)
This works similarly except everything you send from the browser is eval'd on the server!
The sample.lisp file shows a simple integration with usocket, but it should be easy to use with IOLib or web frameworks.
Only supports short (125 byte) messages (I'll fix that soon).
Currently focussed on supporting WebSocket servers, but no reason why it shouln't be a good WebSocket client too.
Doesn't yet support extended features.
Doesn't yet support multi frame messages.
Doesn't yet support ping, pong.
Rob Blackwell
July 2012