Main.hs

{-# LANGUAGE OverloadedStrings #-}
module Main where

import           Control.Applicative
import           Control.Monad.Trans
import           Control.Concurrent
import           Snap.Types
import           Snap.Util.FileServe
import           Snap.Http.Server
import           Snap.Iteratee
import qualified Data.ByteString as B
import           Blaze.ByteString.Builder

main :: IO ()
main = quickHttpServe $
    ifTop (serveFile "static/index.html") <|>
    dir "static" (serveDirectory "static") <|>
    route [ ("eventsource", eventHandler) ]

enum (Continue k) = do
  liftIO $ putStrLn "Type a message"
  x <- liftIO B.getLine
  if x == "q"
    then continue k
    else k (Chunks [x]) >>== enum
enum step = returnI step

bsToBuilderEnum = mapEnum toByteString fromByteString

eventHandler :: Snap ()
eventHandler = do
    modifyResponse $ setContentType "text/event-stream" . 
                     setResponseCode 200 .
                     setResponseBody (bsToBuilderEnum enum)
    r <- getResponse
    finishWith r