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?
websocket_client client;
//start socket connection to server
try {
std::cout << "s
----------
client.connect(U("wss://XZXXXZZy.com/ws?account_id=4de3f308f2f8d3247As70228f94e0d2aAea&ws_key=reception")).wait();
}
catch (const std::exception&e)
{
std::cout << e.what() << std::endl;
}
//send messages to the server
//websocket_outgoing_message msg;
//msg.set_pong_message();
//std::cout << "\n...........2nd.........;";
//std::string data = "hii";
//client.send(msg).then([]() {
//
//
//
//
// /* Successfully sent the message. */ });
//std::cout << " Successfully sent the message.";
//std::cout << "\n...........3rd.........;";
//receive messages from the server
client.receive().then([](websocket_incoming_message msg) {
std::cout << "receiving data from socket";
return msg.extract_string();
}).then([](std::string body) {
//FETCHING THE DATA FROM BODY. "TEXT/JSON"
std::cout << "displaying the data";
std::cout << body << std::endl;
const json::value& v1 = body.substr;
utility::string_t jsonval = v1.serialize();
auto array = v1.at(U("rows")).as_array();
for (int i = 0; i<array.size(); ++i)
{
auto id = array[i].at(U("id")).as_string();
std::wcout << "\n" << id;
auto key = array[i].at(U("key")).as_string();
std::wcout << "\n" << key;
auto array2 = array[i].at(U("value")).as_array();
std::wcout << array2[0];
std::wcout << array2[1];
}
}
);
//close the connection
client.close().then([]() {
std::cout << "successfully close socket connction";
/* Successfully closed the connection. */
});
I have json response in my string body.but i dont know how to parse json data from websocket responses event. i want to display contacts from api responses.please help me..
MY JSON RESPONSES
--------------------------------------
.{"action":"refresh_dashboard","data":{"users_list":[{"user_id":"901e6076ff351cfc2195fb86f8438a26","extensions":["1002"],"name":"Karthik M"},{"user_id":"cc3f94ecc14ee9c55670dcde9adc1887","extensions":["1006"],"name":"Rounak S Kiran"},{"user_id":"6c29ebdb34e1761fdf9423c573087979","extensions":["1003"],"name":"Amar Nath"},{"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":"3258f7ae4ae1db60435cbcf583f64a89","extensions":["1009"],"name":"Test User"},{"user_id":"90bc84e5e8a3427fe35e99bd4386de95","extensions":["1010"],"name":"Prince T"},{"user_id":"b501ef5b270a196afc0eed557ca74237","extensions":["1005","+17325951060"],"name":"Jineed AJ"},{"user_id":"1422af351e06adeab2de92f5a633a444","extensions":["1004"],"name":"Ashok PA"}],"busy_users":[],"reg_users":[{"user_id":"cc3f94ecc14ee9c55670dcde9adc1887","status":"registered"},{"user_id":"901e6076ff351cfc2195fb86f8438a26","status":"registered"},{"user_id":"1422af351e06adeab2de92f5a633a444","status":"registered"},{"user_id":"3258f7ae4ae1db60435cbcf583f64a89","status":"registered"},{"user_id":"b55146df593ec8d09e5fe12a8a4c1108","status":"registered"},{"user_id":"6c29ebdb34e1761fdf9423c573087979","status":"registered"}],"contacts":[{"owner_id":"cc3f94ecc14ee9c55670dcde9adc1887","status":"ready"},{"owner_id":"901e6076ff351cfc2195fb86f8438a26","status":"ready"},{"owner_id":"1422af351e06adeab2de92f5a633a444","status":"ready"},{"owner_id":"3258f7ae4ae1db60435cbcf583f64a89","status":"ready"},{"owner_id":"b55146df593ec8d09e5fe12a8a4c1108","status":"ready"},{"owner_id":"6c29ebdb34e1761fdf9423c573087979","status":"ready"}]}}
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("data.users_list")) {
std::cout << "\n" << "users id " << e.second.get<std::string>("user_id") << "\n";
}
});
useful resources
Parse JSON array as std::string with Boost ptree
C++ boost parse dynamically generated json string (not a file)
I would like to update existing json file.
This is example json file:
{
"Foo": 51.32,
"Number": 100,
"Test": "Test1"
}
Logs from program:
Operation successfully performed
100
"Test1"
51.32
46.32
Done
Looks like everythink works as expected...
If I change fstream to ifstream to read and later ofstream to write it's working...
I tried use debugger and as I see I have wrong data in basic_ostream object... but I dont know why, I use data from string with corrected (updated data).
Any idea what is wrong :-) ?
You have a few problems here.
First the command json json_data(fs); reads to the end of the file setting the EOF flag. The stream will stop working until that flag is cleared.
Second the file pointer is at the end of the file. If you want to overwrite the file you need to move back to the beginning again:
if (fs.is_open())
{
json json_data(fs); // reads to end of file
fs.clear(); // clear flag
fs.seekg(0); // move to beginning
Unfortunately that still doesn't fix everything because if the file you write back is smaller than the one you read in there will be some of the old data tagged to the end of the new data:
std::cout << "Operation successfully performed\n";
std::cout << json_data.at("Number") << std::endl;
std::cout << json_data.at("Test") << std::endl;
std::cout << json_data.at("Foo") << std::endl;
json_data.at("Foo") = 4.32; // what if new data is smaller?
Json file:
{
"Foo": 4.32, // this number is smaller than before
"Number": 100,
"Test": "Test1"
}} // whoops trailing character from previous data!!
In this situation I would simply open one file for reading then another for writing, its much less error prone and expresses the intention to overwrite everything.
Something like:
#include "json.hpp"
#include <iostream>
#include <fstream>
#include <string>
using json = nlohmann::json;
void readAndWriteDataToFile(std::string fileName) {
json json_data;
// restrict scope of file object (auto-closing raii)
if(auto fs = std::ifstream(fileName))
{
json_data = json::parse(fs);
std::cout << "Operation successfully performed\n";
std::cout << json_data.at("Number") << std::endl;
std::cout << json_data.at("Test") << std::endl;
std::cout << json_data.at("Foo") << std::endl;
}
else
{
throw std::runtime_error(std::strerror(errno));
}
json_data.at("Foo") = 4.32;
std::cout << json_data.at("Foo") << std::endl;
std::string json_content = json_data.dump(3);
if(auto fs = std::ofstream(fileName))
{
fs.write(json_content.data(), json_content.size());
std::cout << "Done" << std::endl;
}
else
{
throw std::runtime_error(std::strerror(errno));
}
}
int main()
{
try
{
std::string fileName = "C:/new/json1.json";
readAndWriteDataToFile(fileName);
}
catch(std::exception const& e)
{
std::cerr << e.what() << '\n';
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
during CPPRest SDK (2.8) testing, I initialized an HTTP Request simulating user login to the local server, I am expecting a JSON string to be returned indicating if login succeed. here is the code I wrote.
void printJSON(json::value v)
{
if (!v.is_null()){
// Loop over each element in the object
for (auto iter = v.as_object().cbegin(); iter != v.as_object().cend(); ++iter){
const string &key = iter->first;
const json::value &value = iter->second;
if (value.is_object() || value.is_array()){
if(key.size() != 0){
std::wcout << "Parent: " << key.c_str() << std::endl;
}
printJSON(value);
if(key.size() != 0){
std::wcout << "End of Parent: " << key.c_str() << std::endl;
}
}else{
std::wcout << "Key: " << key.c_str() << ", Value: " << value.to_string().c_str() << std::endl;
}
}
}
}
void login(){
http_client client("http://localhost:8080/user");
http_request request(methods::POST);
request.headers().add("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
request.headers().add("Content-Length", "100");
request.headers().add("Host", "testhost.com");
request.headers().add("X-Requested-With", "XMLHttpRequest");
request.set_body("u_id=test_admin&pwd=123456789");
pplx::task<void> task = client.request(request)
.then([](http_response response)-> pplx::task<json::value>{
if(response.status_code() == status_codes::OK){
return response.extract_json();
} else {
return pplx::task_from_result(json::value());
};})
.then([](pplx::task<json::value> previousTask){
try{
const json::value & v = previousTask.get();
printJSON(v);
} catch(const http_exception &e){
std::cout<<e.what()<<std::endl;
}
});
try{
task.wait();
} catch(std::exception &e){
std::cout<<e.what()<<std::endl;
}
}
When I run this code, nothing happened, it seems request never reaches to the Server which has been tested using JSP, So I am pretty sure something went wrong in my code. please help, thanks
Vague.
If you're saying that the request is not reaching the server, there might be a problem with the listener at the time you executed this code.
Your request format is correct and running, you may try to wrap the body (u_id, pwd) into a json, and see if it works.
The bottomline is debugging or sharing your server code would probably help clarify things a bit more.
I'm writing program using Boost::Asio, I want to implement simple chat. Currently I'm struggling with problem that when I put some code inline of class function it's working, but when same code is provided by another class object is not. I think it could be connected to Boost::Asio, but I'm not sure:
void Connection::session(socket_ptr sock)
{
try{
for(;;) {
char mesg[1024];
boost::system::error_code error;
size_t length = sock->read_some(boost::asio::buffer(mesg), error);
if (error == boost::asio::error::eof){
disconnected(sock);
break;
}
else if (error)
throw boost::system::system_error(error);
message msg(mesg,length);
char *data;
data = msg.getData();
std::cout << "In session " << strlen(data) << " " << data;
/*This is working
string s_msg,s_data;
s_msg = mesg;
s_data = s_msg.substr(2,length);
std::vector<char> writable(s_data.size() + 1);
std::copy(s_data.begin(), s_data.end(), writable.begin());
std::cout << "In session " << strlen(&writable[0]) << " " << &writable[0];
send_all(sock,&writable[0],strlen(&writable[0]));
*/
send_all(sock,data,strlen(data));
}
}
catch (std::exception& e){
std::cerr << "Exception in thread: " << e.what() << "\n";
}
}
Class message that is only parsing data
message::message(char *c_msg, size_t length)
{
msg = c_msg;
id = msg.at(0);
data = msg.substr(2,length);
}
char* message::getData()
{
std::vector<char> writable(data.size() + 1);
std::copy(data.begin(), data.end(), writable.begin());
std::cout << data;
std::cout << &writable[0];
return &writable[0];
}
So when using class message this line:
std::cout << "In session " << strlen(data) << " " << data;
I get:
st String //this is cout from message getData
st String //this is cout from message getData
In session 0
With inline version:
In session 11 st String
So, in session function string is empty although message cout shows something opposite.
I don't know if it's important, but this function is invoked as new thread from main.
Regards,
Piotr
You're returning the address of a temporary:
char* message::getData()
{
std::vector<char> writable(data.size() + 1);
//...
return &writable[0];
}
This is undefined behaviour.
I'm assuming that data is just a std::string. You could do this instead:
const char* message::getData() const
{
return data.c_str();
}
I'm modifying the stock quoter example from the wustl CORBA release. The assignment is to implement a reply handler for the StockFactory class that handles calls to get_stock()
Here's my FactoryHandler implementation:
FactoryHandler_i.h:
#ifndef TAO_TUTORIALS_QUOTER_AMI_CLIENT_FACTORYHANDLER_I_H
#define TAO_TUTORIALS_QUOTER_AMI_CLIENT_FACTORYHANDLER_I_H
#include "QuoterS.h"
class Stock_Factory_Handler_i : public POA_Quoter::AMI_Stock_FactoryHandler
{
public:
Stock_Factory_Handler_i (int *response_count, ::Quoter::Stock_var& result);
void get_stock (::Quoter::Stock_ptr ami_return_val);
void get_stock_excep (::Messaging::ExceptionHolder * excep_holder);
private:
int *response_count_;
::Quoter::Stock_var& result_;
};
#endif /* TAO_TUTORIALS_QUOTER_AMI_CLIENT_HANDLER_I_H */
FactoryHandler_i.cpp:
#include "FactoryHandler_i.h"
#include "ace/streams.h"
Stock_Factory_Handler_i::
Stock_Factory_Handler_i (int *response_count, ::Quoter::Stock_var& result)
: response_count_ (response_count), result_ (result)
{
}
void
Stock_Factory_Handler_i::get_stock (::Quoter::Stock_ptr ami_return_val)
{
cout << "storing result" << endl;
result_ = ami_return_val;
(*this->response_count_)++;
}
void
Stock_Factory_Handler_i::get_stock_excep (::Messaging::ExceptionHolder * excep_holder)
{
// We ignore the exception, but this counts as a response, otherwise
// the application would not finish.
cerr << "Exception raised while getting stock"
<< endl;
(*this->response_count_)++;
}
And the client.cpp, from just before the part where changes have been made:
// ...
// Create and activate the handler...
int response_count = 0;
Single_Query_Stock_Handler_i handler_i (&response_count);
Quoter::AMI_Single_Query_StockHandler_var handler =
handler_i._this ();
// Create and activate the factory handler...
Quoter::Stock_var result;
Stock_Factory_Handler_i factory_handler_i (&response_count, result);
Quoter::AMI_Stock_FactoryHandler_var factory_handler =
factory_handler_i._this();
// Send all the requests, careful with error handling
int request_count = 0;
for (int i = 2; i != argc+1; ++i) {
try {
// Get the stock object
cout << "looking up stock symbol " << argv[i] << endl;
factory->sendc_get_stock (factory_handler.in (), argv[i]);
sleep(3); // wait for a response
cout << "converting result" << endl;
Quoter::Single_Query_Stock_var stock =
Quoter::Single_Query_Stock::_narrow (result.in ());
cout << "checking result" << endl;
CORBA::Any any;
any <<= stock;
CORBA::TypeCode_var tc = any.type();
cout << tc->kind() << endl;
if (CORBA::is_nil (stock.in ())) {
cerr << "Cannot get single query interface for <"
<< argv[i] << ">" << endl;
continue;
}
cout << "reading result" << endl;
stock->sendc_get_price_and_names (handler.in ());
request_count++;
}
catch (Quoter::Invalid_Stock_Symbol &) {
cerr << "Invalid stock symbol <"
<< argv[i] << ">" << endl;
}
}
while (response_count < 2 * request_count // multiply by 2 because both handlers increment response_count
&& orb->work_pending ()) {
orb->perform_work ();
}
// ...
When running the client, the output is:
looking up stock symbol MSFT
converting result
checking result
14
Cannot get single query interface for <MSFT>
(The 14 is the typecode for Stock, that's only for debugging)
Notably missing from the above is the "storing result" message that's supposed to be printed in the FactoryHandler's get_stock() callback method. I'm at a loss as to why, since the sendc_get_stock() method doesn't produce any (immediate) errors and is basically just a copy of the StockHandler's code, and from there it's the responsibility of the AMI/ORB interface to make the callback. But the original example (with a StockHandler only) works fine.
What am I doing wrong (and how do I fix it)?
EDIT: another bit of information: on the server side, StockFactory's get_stock() method does get called.
Sorry, I've no aswer for you. But a hint, ask your question at TOA's maling list at http://www.cs.wustl.edu/~schmidt/ACE-mail.html
HTH
I think that your problem is that work_pending returns true only if the ORB has immediate work to do, so it returns false in the time after your client sent his request and before the server sends his reply.
To validate that, simply remove the && orb->work_pending() condition from the loop, and use the version of perform_work that takes a timeout argument.