ZMQ C++ Req to Router问题

Question

我正在使用ZeroMQ作为我的网络层,到目前为止一切正常,除了ROUTER套接字.特别是我在ROUTER上收到了预期的消息但是当我尝试将回复发送回我的REQ套接字时,从未收到消息.

这是我写的一个相对简单的测试,它试图向ROUTER发送一个"HELLO"消息,并期望一条消息回来.

这里客户端代码:

    try
    {
        zmq::context_t myContext;

        zmq::socket_t reqSocket(myContext, ZMQ_REQ);
        reqSocket.setsockopt(ZMQ_IDENTITY, "REQ", 3);
        reqSocket.connect(gpRouterAddress);

        //request delimiter
        zmq::message_t zmqMsgReqDelimiter(1);
        memcpy ((void *) zmqMsgReqDelimiter.data(), "\0", 1);
        reqSocket.send(zmqMsgReqDelimiter, ZMQ_SNDMORE);

        //some message
        zmq::message_t reqMsg(5);
        memcpy ((void *) reqMsg.data(), "HELLO", 5);
        reqSocket.send(reqMsg, 0);

        int rcvMore = 0;
        size_t sizeInt = sizeof(int);
        bool bRcvMore = true;
        std::vector<std::string> history;

        while(bRcvMore)
        {
            zmq::message_t zmqMsg;

            reqSocket.recv(&zmqMsg, rcvMore);
            const char* pMsgStr = static_cast<char*>(zmqMsg.data());
            history.push_back(pMsgStr);

            reqSocket.getsockopt(ZMQ_RCVMORE, &rcvMore, &sizeInt);

            bRcvMore = (rcvMore == 1);
        }
    }
    catch (zmq::error_t error)
    {
        std::string errorStr = error.what();
    }

这是我的路由器代码(可以在不同的线程中运行,在这种情况下,theContext将与上面的代码中的"myContext"相同)或完全不同的应用程序:

    try
    {
        zmq::context_t theContext;

        zmq::socket_t router (theContext, ZMQ_ROUTER);
        int value = 1;
        router.setsockopt(ZMQ_ROUTER_MANDATORY, &value, sizeof(int));
        router.setsockopt(ZMQ_IDENTITY, "ROUT", 4);
        router.bind(gpRouterAddress);

        zmq::message_t zmqMsgInternalAddress;
        router.recv(&zmqMsgInternalAddress, 0);
        const char* pAddressStr = static_cast<char*>(zmqMsgInternalAddress.data());

        zmq::message_t zmqMsgDelimiter;
        router.recv(&zmqMsgDelimiter, ZMQ_RCVMORE);
        const char* pDelimiterStr = static_cast<char*>(zmqMsgDelimiter.data());

        int rcvMore = 0;
        size_t sizeInt = sizeof(int);
        bool bRcvMore = true;

        router.getsockopt(ZMQ_RCVMORE, &rcvMore, &sizeInt);
        bRcvMore = (rcvMore == 1);

        std::vector<std::string> history;

        while(bRcvMore)
        {
            zmq::message_t zmqMsg;

            router.recv(&zmqMsg, rcvMore);
            const char* pMsgStr = static_cast<char*>(zmqMsg.data());
            history.push_back(pMsgStr);

            router.getsockopt(ZMQ_RCVMORE, &rcvMore, &sizeInt);

            bRcvMore = (rcvMore == 1);
        }


        //reply address

        size_t len = strlen(pAddressStr) - 1; //if I don't subtract 1 char here, an exception will be raised 

        zmq::message_t replyAddress(len);
        memcpy ((void *) replyAddress.data(), pAddressStr, len);
        router.send(replyAddress, ZMQ_SNDMORE);

        //reply delimiter
        zmq::message_t zmqMsgReplyDelimiter(1);
        memcpy ((void *) zmqMsgReplyDelimiter.data(), "\0", 1);
        router.send(zmqMsgReplyDelimiter, ZMQ_SNDMORE);

        //some message
        zmq::message_t replyMsg(5);
        memcpy ((void *) replyMsg.data(), "WORLD", 5);
        router.send(replyMsg, 0);

    }
    catch (zmq::error_t error)
    {
        std::string errorStr = error.what();
    }

我在路由器上收到"HELLO"消息,我可以单步执行ROUTER发送,一切似乎都被发送好了(即没有异常被提出)但我从未在REQ套接字上收到一条消息,它将一直无限期地等待.

根据ZeroMQ指南,我应该期望ROUTER收到以下消息:

REQ套接字发送

empty
HELLO

ROUTER收到

REQ
empty
HELLO

但我收到了

REQ
some binary message
empty
HELLO

我送了

REQ
empty
WORLD

我希望能够到达REQ

empty
WORLD

如果我改为连接到REP套接字(使用简单的REQ-REP拓扑,一切正常).

任何人都可以看到我遗失/做错了什么？

Answer 1

我发现了这个问题.

基本上错误在于我如何发送分隔符

    zmq::message_t zmqMsgReplyDelimiter(1);
    memcpy ((void *) zmqMsgReplyDelimiter.data(), "\0", 1);
    router.send(zmqMsgReplyDelimiter, ZMQ_SNDMORE);

它应该是

    zmq::message_t zmqMsgReplyDelimiter(0);
    router.send(zmqMsgReplyDelimiter, ZMQ_SNDMORE);