+
+-- | Execute a block f that will throw a 'TimeoutException'
+-- after duration seconds. This will override the global timeout
+-- for waiting for messages to arrive defined in 'SessionConfig'.
+withTimeout :: Int -> Session a -> Session a
+withTimeout duration f = do
+ chan <- asks messageChan
+ timeoutId <- curTimeoutId <$> get
+ modify $ \s -> s { overridingTimeout = True }
+ liftIO $ forkIO $ do
+ threadDelay (duration * 1000000)
+ writeChan chan (TimeoutMessage timeoutId)
+ res <- f
+ modify $ \s -> s { curTimeoutId = timeoutId + 1,
+ overridingTimeout = False
+ }
+ return res