creating a RedisTimeoutException, but still defaulting to NoNodeExcep…

…tion for now

src/Database/Redis/Cluster.hs

@@ -125,6 +125,15 @@ instance Exception CrossSlotException
 data NoNodeException = NoNodeException  deriving (Show, Typeable)
 instance Exception NoNodeException
 
+data BusyNodeException = BusyNodeException deriving (Show, Typeable)
+instance Exception BusyNodeException
+
+data RedisTimeoutException e = TimeoutException e deriving (Show, Typeable)
+instance (Show e, Typeable e) => Exception (RedisTimeoutException e)
+
+timeoutDueTo :: (Exception e, Show e, Typeable e) => e -> RedisTimeoutException e
+timeoutDueTo = TimeoutException
+
 connect :: (Host -> CC.PortID -> Maybe Int -> IO CC.ConnectionContext) -> [CMD.CommandInfo] -> MVar ShardMap -> Maybe Int -> Bool -> ([NodeConnection] -> IO ShardMap) -> Time.NominalDiffTime -> Int -> IO Connection
 connect withAuth commandInfos shardMapVar timeoutOpt isReadOnly refreshShardMap idleTime maxResources = do
         shardMap <- readMVar shardMapVar
@@ -447,7 +456,7 @@ requestNode (NodeConnection pool lastRecvRef nid) requests = withResource pool $
     eresp <- race (requestNodeImpl ctx) (threadDelay envTimeout)
     case eresp of
         Left e -> return e
-        Right _ -> putStrLn ("timeout happened" ++ show nid) *> throwIO NoNodeException
+        Right _ -> putStrLn ("timeout happened" ++ show nid) *> (throwIO $ timeoutDueTo NoNodeException)
     where
     requestNodeImpl :: CC.ConnectionContext -> IO [Reply]
     requestNodeImpl ctx = do