module Network.Wai.Handler.WebSockets
( intercept
, interceptWith
) where
import Control.Monad.IO.Class (liftIO)
import Data.ByteString (ByteString)
import Data.Char (toLower)
import qualified Data.ByteString.Char8 as S
import qualified Data.Conduit as C
import qualified Data.Enumerator as E
import qualified Network.Wai as Wai
import qualified Network.Wai.Handler.Warp as Warp
import qualified Network.WebSockets as WS
intercept :: WS.Protocol p
=> (WS.Request -> WS.WebSockets p ())
-> Wai.Request
-> Maybe (C.Source (C.ResourceT IO) ByteString -> Warp.Connection -> C.ResourceT IO ())
intercept = interceptWith WS.defaultWebSocketsOptions
interceptWith :: WS.Protocol p
=> WS.WebSocketsOptions
-> (WS.Request -> WS.WebSockets p ())
-> Wai.Request
-> Maybe (C.Source (C.ResourceT IO) ByteString -> Warp.Connection -> C.ResourceT IO ())
interceptWith opts app req = case lookup "upgrade" $ Wai.requestHeaders req of
Just s
| S.map toLower s == "websocket" -> Just $ runWebSockets opts req' app
| otherwise -> Nothing
_ -> Nothing
where
req' = WS.RequestHttpPart (Wai.rawPathInfo req) (Wai.requestHeaders req)
(Wai.isSecure req)
runWebSockets :: WS.Protocol p
=> WS.WebSocketsOptions
-> WS.RequestHttpPart
-> (WS.Request -> WS.WebSockets p ())
-> C.Source (C.ResourceT IO) ByteString
-> Warp.Connection
-> C.ResourceT IO ()
runWebSockets opts req app source conn = do
step <- liftIO $ E.runIteratee $ WS.runWebSocketsWith opts req app send
source C.$$ C.sinkState (E.returnI step) push close
where
send = iterConnection conn
push iter bs = do
step <- liftIO $ E.runIteratee $ E.enumList 1 [bs] E.$$ iter
return $ C.StateProcessing $ E.returnI step
close iter = do
_ <- liftIO $ E.runIteratee $ E.enumEOF E.$$ iter
return ()
iterConnection :: Warp.Connection -> E.Iteratee ByteString IO ()
iterConnection c = E.continue go
where
go (E.Chunks []) = E.continue go
go (E.Chunks cs) = E.tryIO (Warp.connSendMany c cs) >> E.continue go
go E.EOF = E.continue go