CPPRestSDK (casablanca) Extract JSON From Incoming WebSocket Messages (malformed token)

Question

I'm connecting to a WebSocket whom always replies in JSON. I see there is an extract_string method for websocket_incoming_message however after trying numerous things with json:value it seems as though you can only construct JSON arrays on-the-fly by inserting key-value pairs one-by-one. Am I missing something here or is there a way to take the output from websocket_incoming_message and directly convert it into a json:value array?

    wsClient.set_message_handler([=](websocket_incoming_message msg)
    {
        // handle message from server...
        printf("[WebSocket INBOUND]: %s", msg.extract_string().get().c_str());
        printJSON(json::value::parse(conversions::to_string_t(msg.extract_string().get())));
    });

printJSON runs through the json::value and prints each key-value-pair.

Unhandled exception at 0x00007FF866923FB8 in RestAPI.exe: Microsoft C++ exception: web::json::json_exception at memory location 0x0000003E553FDDC0. occurred

Console Output:

[WebSocket INBOUND]: {"t":null,"s":null,"op":10,"d":{"heartbeat_interval":41250,"_trace":["gateway-prd-main-cr3x"]}}

Even though we can compile and run the application, I figure the exception is being caused due to the fact that were passing a string containing a JSON Table and not a single element? Does this mean I need to manually parse the string and pull out each key-value-pair while simultaneously building the json array?

There must be a way to do this, it seems like basic needed functionality..

A similar unresolved question

Any help here would be greatly appreciated! Thank you for your time.

i am searching for how to parse json data from incoming websocket messages — Prince, Mar 08 '18 at 07:15

score 3 · Accepted Answer · answered Mar 15 '18 at 12:28

3

Try catching web::json::json_exception and print the message, it may give you a hint about what's wrong

answered Mar 15 '18 at 12:28

hks

71
4

i can see the data from the socket but unable to parse the data using jsoncpp packages .That is my question.I have implemented proper exception handling mechanisms. – Prince Mar 15 '18 at 13:04
jsoncpp packages showing error when i added from nuget. – Prince Mar 15 '18 at 14:12
@hks.not helpul – Prince Mar 16 '18 at 06:57

Prince · Answer 2 · 2018-03-16T12:08:12.807

I got the complete solution .please try to use boost pacakges from nuget. The documentation will help you to parse the json data from string. I think jsoncpp is not an updated packages available in the nuget.so please try boost packages available in the nuget.

MYJSON STRING

{"action":"refresh_dashboard","data":{"users_list":[{"user_id":"901e6076ff351cfc2195fb86f8438a26","extensions":["1002"],"name":"Karthik M"},{"user_id":"7d617ef5b2390d081d901b0d5cd108eb","extensions":["1015"],"name":"Synway User2"},{"user_id":"c8f667f7d663e81f6e7fa34b9296f067","extensions":["1012"],"name":"Rahib Video"},{"user_id":"cc3f94ecc14ee9c55670dcde9adc1887","extensions":["1006"],"name":"Rounak S Kiran"},{"user_id":"6c29ebdb34e1761fdf9423c573087979","extensions":["1003"],"name":"Amar Nath"},{"user_id":"8e15c2d95d4325cb07f0750846966be8","extensions":["1011"],"name":"TLS User"},{"user_id":"2fc4142bdacf83c1957bda0ad9d50e3d","extensions":["1014"],"name":"Synway User1"},{"user_id":"74d5b5a9aca1faa4c2f217ce87b621d8","extensions":["1008"],"name":"Robin Raju"},{"user_id":"a7ad7e73bf93ea83c8efdc1723cba198","extensions":["1007"],"name":"Arshad Arif"},{"user_id":"b55146df593ec8d09e5fe12a8a4c1108","extensions":["1001"],"name":"Rahib Rasheed"},{"user_id":"391391de005a8f5403c7b5591f462ea1","extensions":["1013"],"name":"Sangeeth J"},{"user_id":"3258f7ae4ae1db60435cbcf583f64a89","extensions":["1009"],"name":"Aby TL"},{"user_id":"90bc84e5e8a3427fe35e99bd4386de95","extensions":["1010"],"name":"Prince T"},{"user_id":"b501ef5b270a196afc0eed557ca74237","extensions":["1005"],"name":"Jineed AJ"},{"user_id":"1422af351e06adeab2de92f5a633a444","extensions":["1004"],"name":"Ashok PA"}],"busy_users":[],"reg_users":[{"user_id":"901e6076ff351cfc2195fb86f8438a26","status":"registered"},{"user_id":"6c29ebdb34e1761fdf9423c573087979","status":"registered"}],"contacts":[{"owner_id":"901e6076ff351cfc2195fb86f8438a26","status":"ready"},{"owner_id":"6c29ebdb34e1761fdf9423c573087979","status":"ready"}]}}

CODES

client.receive().then([](websocket_incoming_message msg) {
            std::cout << "receiving data from socket";

            // msg.message_type();
            return msg.extract_string();
            //1..i have one string
            //cout<<"\n///////////test"<< msg.extract_string().get().c_str();
            //  // 2.convert to json array
            //json::value::parse(   ::to_string_t(msg.extract_string().get()))
            //

        }).then([](std::string body) {

            //std::cout << "displaying the data";
            std::cout << body << std::endl;


            std::string ss = body;
            ptree pt;
            std::istringstream is(ss);
            read_json(is, pt);

            std::cout <<"\n 1st"<< "action:     " << pt.get<std::string>("action") << "\n";
            std::cout <<"\n 2nd"<< "data: " << pt.get<std::string>("data") << "\n";
            std::cout << "--------------------------------------------------------------";
            for (auto& e : pt.get_child("users_list")) {
                std::cout << "\n" << "users list " << e.second.get<std::string>("user_id") << "\n";



            }
        });

CPPRestSDK (casablanca) Extract JSON From Incoming WebSocket Messages (malformed token)

2 Answers2

MYJSON STRING

CODES

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