No route info of this topic Error when sending msg sync in cpp, but everything normal when using the same library from python api.

[SandyKidYao]

The msg producer works with python api but not working in cpp. The error msg is "No route info of this topic: ".

In fact the python api is rely on the cpp client, and it works fine while the cpp codes don't, I hope someone can give a little help with my problem ( I run the example and got the similar error).

• OS: centos 7 (docker image from the official centos, tag 7.9.2009)
• RocketMQ version: 4.7.1(built and installed from the source code with maven, the JAVA_OPT in runserver.sh and runbroker.sh are modified like "-Xms256m -Xmx256m -Xmn128m -XX:MetaspaceSize=128m -XX:MaxMetaspaceSize=320m")
• rocketmq-client-cpp version : 2.0.0 and 2.2.0, installed via the rpm pkg got from the release page
• rocketmq-client-python version : 2.0.0, installed via pip

The test code (c-style) in cpp like below

int main(int argc, const char *argv[]) {
    CProducer* producer = CreateProducer("Group_producer");
    SetProducerNameServerAddress(producer, "127.0.0.1:9876");
    StartProducer(producer);
    CMessage* msg = CreateMessage("T_TestTopic");
    std::string body = "hello";
    SetMessageBody(msg, body.c_str());
    CSendResult result;
    int status = SendMessageSync(producer, msg, &result);
    if (status == OK) {
        std::cout<<"send msg success " <<result.msgId << " "  << result.offset <<" " << (int)result.sendStatus<<std::endl;

    } else {
        std::cout<<"send msg failed"<<std::endl;
    }
    ShutdownProducer(producer);
    DestroyProducer(producer);
}

And the cpp-style test code

#include<rocketmq/DefaultMQProducer.h>

int main(int argc, const char *argv[]) {

    rocketmq::DefaultMQProducer producer("please_rename_unique_group_name");
    producer.setNamesrvAddr("127.0.0.1:9876");
    producer.start();
    rocketmq::MQMessage msg("channel_test", "{\"channel\": \"channel_001\"}");
    producer.send(msg);
    producer.shutdown();

}

The test code in python works fine, like this.

from rocketmq.client import Producer, Message

producer = Producer('PID-XXX')
producer.set_name_server_address(HOST)
producer.start()
msg = Message(TOPIC)
msg.set_body("hello")
ret = producer.send_sync(msg)
print(ret.status, ret.msg_id, ret.offset)
producer.shutdown()

The logs generated by cpp codes are a little different from the ones by python code. There are lots of warnings. I tried to figure out what happened but got noting valuable.

[2021-Feb-03 09:00:20.043586](warning):waitResponse of code:105 with opaque:8 timeout[waitResponse:61]
[2021-Feb-03 09:00:20.043956](warning):wait response timeout or get NULL response of code:105, so closeTransport of addr:[invokeSync:217]
[2021-Feb-03 09:00:20.044166](warning):closeTransport: disconnect:127.0.0.1:9876 with state:2[CloseTransport:429]
[2021-Feb-03 09:00:20.044593](warning):closeTransport: erase broker: 127.0.0.1:9876[CloseTransport:432]
[2021-Feb-03 09:00:20.044931](warning):Get topic[T_TestTopic] route failed [Null Response].[getTopicRouteInfoFromNameServer:338]
[2021-Feb-03 09:00:25.047442](warning):waitResponse of code:105 with opaque:9 timeout[waitResponse:61]
[2021-Feb-03 09:00:25.047591](warning):wait response timeout or get NULL response of code:105, so closeTransport of addr:[invokeSync:217]
[2021-Feb-03 09:00:25.047664](warning):closeTransport: disconnect:127.0.0.1:9876 with state:2[CloseTransport:429]
[2021-Feb-03 09:00:25.047908](warning):closeTransport: erase broker: 127.0.0.1:9876[CloseTransport:432]
[2021-Feb-03 09:00:25.048088](warning):Get topic[TBW102] route failed [Null Response].[getTopicRouteInfoFromNameServer:338]
[2021-Feb-03 09:00:25.048147](warning):tryToFindTopicPublishInfo null:T_TestTopic[tryToFindTopicPublishInfo:155]
[2021-Feb-03 09:00:25.048178](warning):Retry many times, still failed[sendDefaultImpl:431]
[2021-Feb-03 09:00:30.049733](warning):waitResponse of code:105 with opaque:10 timeout[waitResponse:61]
[2021-Feb-03 09:00:30.049868](warning):wait response timeout or get NULL response of code:105, so closeTransport of addr:[invokeSync:217]
[2021-Feb-03 09:00:30.049935](warning):closeTransport: disconnect:127.0.0.1:9876 with state:2[CloseTransport:429]
[2021-Feb-03 09:00:30.050166](warning):closeTransport: erase broker: 127.0.0.1:9876[CloseTransport:432]
[2021-Feb-03 09:00:30.050240](warning):Get topic[T_TestTopic] route failed [Null Response].[getTopicRouteInfoFromNameServer:338]
[2021-Feb-03 09:00:35.029496](warning):sendheartbeat brokeradd is empty[sendHeartbeatToAllBroker:772]
[2021-Feb-03 09:00:35.051976](warning):waitResponse of code:105 with opaque:11 timeout[waitResponse:61]
[2021-Feb-03 09:00:35.052085](warning):wait response timeout or get NULL response of code:105, so closeTransport of addr:[invokeSync:217]
[2021-Feb-03 09:00:35.052151](warning):closeTransport: disconnect:127.0.0.1:9876 with state:2[CloseTransport:429]
[2021-Feb-03 09:00:35.052344](warning):closeTransport: erase broker: 127.0.0.1:9876[CloseTransport:432]
[2021-Feb-03 09:00:35.052410](warning):Get topic[TBW102] route failed [Null Response].[getTopicRouteInfoFromNameServer:338]
[2021-Feb-03 09:00:35.052447](warning):tryToFindTopicPublishInfo null:T_TestTopic[tryToFindTopicPublishInfo:155]
[2021-Feb-03 09:00:35.052475](warning):Retry many times, still failed[sendDefaultImpl:431]

[ifplusor]

@SandyKidYao Can you show more logs? or test the re_dev branch.

[SandyKidYao]

Thx for reply. These are the logs I copied from the /root/logs/rocketmq-cpp folder.

• 13128** is the one that generated when I run the python test code, which works fine.
• 13390** is the one that generated by the cpp-style test code, which cannot send the msg and gets the route error.
• 13192** is got from the c-style codes, which doesn't work either.

13390_rocketmq-cpp.log 13128_rocketmq-cpp.log 13192_rocketmq-cpp.log

BTW, when I use the cpp test codes (both cpp-style and c-style), the log from rocket mq nameserver shows that they have connected to the nameserver while the log from the broker print nothing. I guess there may be sth wrong in the connection between my cpp program and the broker.

[ifplusor]

@SandyKidYao Can you compile cpp sdk from source?

[SandyKidYao]

I figured out what's wrong in my codes. If I link the librocketmq.so from CMake by TARGET_LINK_LIBRARIES(), the route error will happen. However, if I add the same lib (no matter installed via rpm or built from source code) through CMAKE_CXX_FLAGS, everything works fine.

THX for your time again.

[ifplusor]

It is crazy. In my opinion, TARGET_LINK_LIBRARIES is correct way, and it is better then use CMAKE_CXX_FLAGS.

[SandyKidYao]

It is crazy. In my opinion, TARGET_LINK_LIBRARIES is correct way, and it is better then use CMAKE_CXX_FLAGS.

While I am using other libs in my program too, it may be related to the link order between these libs.

[ifplusor]

@SandyKidYao The re_dev branch is recommend to use, you can test it.