websocketpp获取nginx反代后的客户端真实ip

测试代码：
server::connection_ptr con = m_server.get_con_from_hdl(hdl);
auto addr = con->get_socket().remote_endpoint().address();
auto host = con->get_host();
auto uri = con->get_uri();
auto _request = con->get_request();
auto raw_head = con->get_request().raw_head();
auto param2 = con->get_request().get_headers();
auto param3 = con->get_request().raw();
auto param4 = con->get_request_header("X-Real_IP");
auto param5 = con->get_request_header("X_Forward_For");