I am currently trying to get a working tls websocket client running in C++ (which is a pain in the ass) and I have tried CPP Rest SDK as well as Websocket++. Both spit out a bunch of compile errors (see below). When I tried compiling it using Websocket++ without tls, it compiles so the error clearly is related to SSL.
I tried different OpenSSL versions (1.0.1, 1.0.2, 1.1.0), different C++ versions (11, 14 and even 17), and I just can't get it to compile.
I googled and none of the solutions worked. I am on Ubuntu 16 and the build command I am using looks like this:
g++ source/* -o test.out -Iinclude/ -std=c++14 -L/lib64 -lcurl -lboost_system -lssl -lcrypto -l pthread
Here are some of the errors:
/usr/include/boost/asio/ssl/detail/impl/openssl_init.ipp: In constructor ‘boost::asio::ssl::detail::openssl_init_base::do_init::do_init()’:
/usr/include/boost/asio/ssl/detail/impl/openssl_init.ipp:43:23: error: expected id-expression before ‘(’ token
mutexes_.resize(::CRYPTO_num_locks());
/usr/include/boost/asio/ssl/detail/impl/engine.ipp:221:9: error: ‘SSL_R_SHORT_READ’ was not declared in this scope
ERR_PACK(ERR_LIB_SSL, 0, SSL_R_SHORT_READ),
And here is the basic source code:
#include <websocketpp/config/asio_client.hpp>
#include <websocketpp/client.hpp>
#include <iostream>
// pull out the type of messages sent by our config
typedef websocketpp::config::asio_tls_client::message_type::ptr message_ptr;
typedef websocketpp::client<websocketpp::config::asio_tls_client> client;
using websocketpp::lib::placeholders::_1;
using websocketpp::lib::placeholders::_2;
using websocketpp::lib::bind;
void on_close(client* c, websocketpp::connection_hdl hdl) {
c->get_alog().write(websocketpp::log::alevel::app, "Connection Closed");
}
int main(int argc, char* argv[]) {
client c;
std::string uri = "wss://gateway.discord.gg/";
if (argc == 2) {
uri = argv[1];
}
try {
// set logging policy if needed
c.clear_access_channels(websocketpp::log::alevel::frame_header);
c.clear_access_channels(websocketpp::log::alevel::frame_payload);
//c.set_error_channels(websocketpp::log::elevel::none);
// Initialize ASIO
c.init_asio();
// Register our handlers
c.set_open_handler(bind(&on_open,&c,::_1));
c.set_fail_handler(bind(&on_fail,&c,::_1));
c.set_message_handler(bind(&on_message,&c,::_1,::_2));
c.set_close_handler(bind(&on_close,&c,::_1));
// Create a connection to the given URI and queue it for connection once
// the event loop starts
websocketpp::lib::error_code ec;
client::connection_ptr con = c.get_connection(uri, ec);
c.connect(con);
// Start the ASIO io_service run loop
c.run();
} catch (const std::exception & e) {
std::cout << e.what() << std::endl;
} catch (websocketpp::lib::error_code e) {
std::cout << e.message() << std::endl;
} catch (...) {
std::cout << "other exception" << std::endl;
}
}