[THRIFT-1223] AS3 extension - Socket IO, asnychronous calls, callbacks

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Won't Fix
• Fix Version/s: 0.15.0
• Component/s: AS3 - Compiler, AS3 - Library
• Labels: AS3 Async Compiler Library
• Patch Info: Patch Available
• Assignee: Jens Geyer
• Reporter: Matthias Einwag
• Created: 28/Jun/11 15:30
• Updated: 13/Feb/21 13:49
• Resolved: 13/Feb/21 13:49

Description

Hi everyone,

first of all I'm new to Thrift and JIRA, so I hope I can get this right.
I will try to attach my modified version of the AS3 generator and the AS3 libs.

I did some work on the AS3 implementation of thrift to get TCP/IP socket support. This includes a new transport TSocket.
Because actionscript supports only non-blocking IO you must use TFramedTransport, which is also added and wraps around TSocket.
Some example code to create a framed transport:
private var socket:Socket;
private var transport:TIOStreamTransport;
private var framedTransport:TFramedTransport;

socket = new Socket("127.0.0.1",9090);
transport = new TSocket(socket);
transport.open();
framedTransport = new TFramedTransport(transport);

As I did not like the current asynchronous implementation of Thrift/AS3, I did some further changes:

• For each service function a send function and a receive function is generated
• The send function sends the data over the transport and creates an AsyncResult object (similar to the Deferred in the Py-Twisted implementation), which stores error and success callback functions as well as the corresponding receive function. I would also like to add a timeout timer later to this.
• I now use a processor object for clients and servers. The processor registers at the transport and is notified when a new Frame was received. Then process() is called which decodes one message. The processor has a dictionary that contains the sent requests (TAsyncResult objects). If a response message is requested the processor calls the recveive function for the request, which will then lead to a success or error call. This is not similar to the Java and Py-Twisted implementation where the sequence id and dictionary is stored in the client. But I find it more useful because I can support callbacks (see later).
• The generic implementation TProcessor can be used to support client only functionality.
  Example:
  protocol = new TBinaryProtocol(framedTransport);
  processor = new TProcessor(protocol);
  client = new ServiceClient(processor);
  TAsyncResult ar = client.send_doSomething(successHandler,errorHandler);

• Derived processors are used for server side functionality and callbacks
  Example:
  service = new ServiceProcessor(theComponentThatImplementsTheServiceInterface,protocol);
  Now this type of processor can be used to send requests (creating a client as seen above) and meanwhile will also process incoming requests for the specified service.
  I need to use this for callbacks (events that are sent spontaneously from the server to the actionscript client)

Missing:

• Improved error handling. At the moment the as3 client does not detect if the server disconnect, only if it sends a request.
• "Real" server side functionality. Would need a serversocket that creates a new serviceProcessor for each client that connects.
• The older HTTP transports are currently not compatible. They have to be changed to the new processor usage and must send a TMessageReceivedEvent to the processor. Maybe some minor changes I could add, but I have no time to test HTTP.