Subscribe to IOT Core multiple topics using AWS Green Grass IPC SDK for CPP

[chandar1]

Hi All,

I'm using the sample code given in the SDK (code to subscribe to a single topic) and trying to extend to subscribe to multiple topics, with no luck...
Below is the code I'm using ... need to be able to call SubscribeToIoTCore for multiple topics.

bool SubscribeToIoTCore(std::string topic)
{
    auto stream_handler = MakeShared<SubscribeIoTCoreHandler>(DefaultAllocator());
    auto subscribe_operation = m_ipc_client->NewSubscribeToIoTCore(stream_handler);

    SubscribeToIoTCoreRequest subscribeRequest;
    subscribeRequest.SetQos(QOS_AT_LEAST_ONCE);
    subscribeRequest.SetTopicName(topic.c_str());

    auto requestStatus = subscribe_operation->Activate(subscribeRequest).get();
    if (!requestStatus)
    {
        return false;
    }

    auto subscribeResultFuture = subscribe_operation->GetResult();
    auto subscribeResult = subscribeResultFuture.get();
    if (subscribeResult)
    {
        return true;
    }

    return false;
} 

and I would call this function like,

SubscribeToIoTCore("topic1");
SubscribeToIoTCore("topic2");
SubscribeToIoTCore("topic3");

In all 3 calls, function would return a true, but however receiving messages ONLY on the last subscription "topic3"
Not receiving any messages on topic1 and topic2.

What's the right way to use the SDK, for subscribing to multiple topics?

Thanks,

[jmklix]

@github-actions proposed-answer

Can you try using a shared stream_handler and subscribe_operation? Only initialize them once and pass subscribe_operation as a parameter for your function.

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