CPPRESTSDK fails to retrieve results when request api/iomonitor.

Answered

Y.Nemoto

March 17, 2023 02:34

This is the person who asked a question about getting the switch state of the IO device last time.

https://support.networkoptix.com/hc/en-us/community/posts/12593602492823-Able-to-get-the-status-of-externally-attached-IO-devices-like-AXIS-P8221-via-Nx-API- 

 

When I request the api/iomonitor API using CPPRESTSDK, I get a 200 OK response,
When I run the extract_json() method and try to get the results, I get no response from the method.

 

Below is a sample code.

pplx::task<json::value> getIODeviceStatus(const std::string& inUrl)
{
    const std::string sUrl = inUrl;

    return pplx::create_task([sUrl]
    {
        // setup connection config
        web::http::client::http_client_config conf;
        conf.set_timeout((std::chrono::microseconds)10000);

        utility::string_t sUtf16 = utility::conversions::utf8_to_utf16(sUrl);
        sUtf16 = uri::encode_uri(sUtf16, uri::components::component::query);
        web::http::client::http_client client(sUtf16, conf);
        web::http::http_request cRequest(methods::GET);
        return client.request(cRequest);
    }).then([sUrl](http_response cResponse)
    {
        if (cResponse.status_code() == status_codes::OK)
        {
            ::printf("[GET] %s success. \n", sUrl.c_str());
            http_headers cHeader = cResponse.headers();
        }
        else
        {
            ::printf("[E][GET] %s failed. status=%d \n", sUrl.c_str(), cResponse.status_code());
        }
        return cResponse.extract_json(true);
    });
}

Run this method like this:

getIODeviceStatus("http://[NxWitness VMS Server]/api/iomonitor?cameraid=[iodeviceid]").wait();

When I run this code I get no response when I run cResponse.extract_json(true) method call.

 

Is this related to the fact that the api/iomonitor API is a regular monitoring API?

0

• 

  Andrey Terentyev

  • Network Optix team

  March 20, 2023 13:12

  Hello,

  The /api/iomonitor API should be used in a specific way.

  You should establish HTTPS connect and keep it open. The Server will periodically send updated IO status over this HTTPS connection.

  Hope this helps in refactoring your code.

  0
• 

  Y.Nemoto

  March 23, 2023 00:56

  thank you for answering!

   

  That seems to be the only way.

   

  I will re-implement it like the answer you gave me.

  0

Please sign in to leave a comment.