[web-devel] Handling disconnection in wai or warp

[Hiromi ISHII]

Hi there,

I am writing a simple server which returns infinite stream of data to client like Twitter's streaming API.

I have to manage the number of clients and the connection times of each one.
So I have to handle disconnections during server sending a response to the client.

I'm currently considering using wai (+warp) or snap framework.
My code fragments for snap and wai are below:

==== snap ver. application ====
stream :: Application ()
stream = do
  req <- withRequest $ return . (rqRemoteAddr &&& rqRemotePort)
  writeLBS $ LBS.unlines $ map (LBS.pack . show) [1..] -- I have to handle disconnection here
==== end ====

==== wai ver. ====
streamHandler :: Application
streamHandler req = do
  return $ responseLBS statusOK
                       [ ("Content-Type", "application/json")
                       , ("Transfer-Encoding", "chunked")
                       ]
                       (LBS.unlines $ map (LBS.pack . show) [1..]) -- I have to handle disconnection here
==== end ====


Thanks,

-- Hiromi ISHII