How to implement an XML-RPC server in AS3 (Flash or AIR runtime)?

Question

I'm looking for a good XML-RPC server implementation to be included as part of an existing Flash+AS3 application in order to be notified on events by a client.

The ideal implementation should be well written, documented, reliable and encapsulated in order to be easily and cleanly wrapped.

EDIT:
I'm working on porting the app on Adobe AIR runtime, will this execution environment bypass the listening socket limitation? If yes, any doc about this issue?

Answer 1

Well, XML-RPC specifies using HTTP as transport protocol. Since Flash can not listen on sockets (only connect to them) I do not believe it would be directly possible to create an actual XML-RPC server with Flash.

That being said, a client is definately possible, and has been done a couple of times:

http://code.google.com/p/as3-rpclib

http://danielmclaren.net/2007/08/03/xmlrpc-for-actionscript-30-free-library

The second one is a port of an AS1/2 library.

Answer 2

Can anyone confirm Air 2 will be able to create Listening sockets?

Answer 3

I found this article talking about a SocketMonitor framework.

In the example given it uses this piece of code

var myIstance = 
   Components.classes["@mozilla.org/network/server-socket;1"]
   .createInstance(Components.interfaces.nsIServerSocket);

That really resemble to a listening socket server, but I'm afraid it is only a good implementation of a poll mechanism.