zeromq and protobuf example by haskell

message.proto

package notification;

option java_package = "meta.phor";
option java_outer_classname = "NotificationMessageProtos";

enum EncryptType {
    NONE = 0;
    DYNAMIC_AES = 1;
    APP_SECRET_AES = 2;
}


message NotificationMessage {
    required bytes content = 1;
    required string id = 2;
    required fixed64 sendTime = 3;
    required float version = 4;
    optional EncryptType encryptType = 5 [default = NONE];
}


message EncryptedContent {
    required bytes content = 1;
    required string magic  = 2;
}

ProtobufTest.hs

module ProtobufTest where

import System.ZMQ3
import Control.Monad
import Data.ByteString.UTF8 as U
import Control.Concurrent (threadDelay)

import NotificationMessageProtos.NotificationMessage as N
import NotificationMessageProtos.EncryptType
import Text.ProtocolBuffers.WireMessage (messageGet)
import qualified Data.ByteString as ByteString
import qualified Data.ByteString.Lazy as LB

main :: IO ()
main = runSub "" "tcp://127.0.0.1:8555"

-- topic -> addr
runSub :: String -> String -> IO ()
runSub topic address = withContext $ \ ctx -> 
  		withSocket ctx Sub $ \ socket ->
			subscribe socket (fromString topic) >>
			connect socket address >>
			(forever $ recv socket) >> 	return ()
		where recv socket = receiveMulti socket >>= \bs -> 
				deserializeByProtobuf bs 


deserialize :: [ByteString] -> IO ()
deserialize bs = forM_ bs (putStrLn . U.toString)

deserializeByProtobuf :: [ByteString] -> IO ()
deserializeByProtobuf ( topic : content : [] ) = (putStrLn $ "topic: " ++ U.toString topic) >> 
		printMessage content
	where 
		printMessage content = case messageGet (LB.fromStrict content) of
				Right (notify, x) | LB.length x == 0 -> putStrLn $ showNotify notify -- :: NotificationMessage)
				Right (notify, x) | LB.length x /= 0 -> error  "Failed to parse the message"
				Left errorMessage ->  error errorMessage
		showNotify :: NotificationMessage -> String
		showNotify msg = "content : " ++ (U.toString . LB.toStrict . N.content) msg



deserializeByProtobuf xs = deserialize xs