Qt寫websocketpp服務端

一、下載websocketpp，地址爲https://github.com/zaphoyd/websocketpp，版本爲0.7。

二、下載boost，地址爲https://www.boost.org/，版本爲1.6.3。

三、說明：websocketpp並非必須須要boost，若是C++編譯爲C11以上，是能夠不用的。

四、Qt建立一個console工程(如：websocketServer)，將下載下來的websocket_master裏面的websocket文件夾放到該工程目錄下，在webSocketServer.pro文件中添加include(websocket/websocket.pri)，

五、建立websocket_server類，頭文件websocket_server.h內容以下：

#include <websocketpp/config/asio_no_tls.hpp>
#include <websocketpp/server.hpp>

#include <websocketpp/impl/connection_impl.hpp>
#include <websocketpp/config/core.hpp>
#include <websocketpp/connection.hpp>
#include <websocketpp/endpoint.hpp>
#include <websocketpp/close.hpp>
#include <websocketpp/uri.hpp>

#include <map>
#include <string>
#include <sstream>
#include <cstdlib>
#include <iostream>
#include <QDateTime>

using websocketpp::lib::placeholders::_1;
using websocketpp::lib::placeholders::_2;

using websocketpp::lib::bind;
using websocketpp::endpoint;
using websocketpp::connection;

typedef websocketpp::server<websocketpp::config::asio> server;
typedef server::message_ptr message_ptr;

/////////////////////////////////////////////////////////////////////
class connection_metadata
{
public:
    typedef websocketpp::lib::shared_ptr<connection_metadata> ptr;
    connection_metadata(websocketpp::connection_hdl hdl,std::string strRemote) :
        m_hdl(hdl),strRemote(strRemote)
    {}

    void setDateTime()
    {
        dt = QDateTime::currentDateTime();
    }

    QDateTime getDateTime() const
    {
        return dt;
    }

    void sethdl(websocketpp::connection_hdl hdl)
    {
        m_hdl = hdl;
    }

    websocketpp::connection_hdl gethdl()
    {
        return m_hdl;
    }

    void update_time()
    {
        dt = QDateTime::currentDateTime();
    }

    void setRemote(std::string strRemote)
    {
        this->strRemote = strRemote;
    }

    std::string getRemote() const
    {
        return strRemote;
    }

private:
    QDateTime dt;
    std::string strRemote;
    websocketpp::connection_hdl m_hdl;
};

/////////////////////////////////////////////////////////////////////

class websocket_server
{
public:
    websocket_server();
    ~websocket_server();

    static void on_open(server* s,websocket_server* pWebSocket,websocketpp::connection_hdl hdl);
    static void on_close(server* s,websocket_server* pWebSocket,websocketpp::connection_hdl hdl);
    static void on_message(server* s,websocket_server* pWebSocket,websocketpp::connection_hdl hdl,message_ptr msg);

    void start(int port);

private:
    typedef std::map<std::string,connection_metadata::ptr> con_list;

    server echo_server;
    con_list m_connection_list;

    websocketpp::lib::shared_ptr<websocketpp::lib::thread> m_thread;
};

六、websocket_server.cpp內容以下：      

websocket_server::websocket_server()
{
    m_connection_list.clear();
}

websocket_server::~websocket_server()
{
    for(con_list::iterator iter = m_connection_list.begin();iter != m_connection_list.end();)
    {
        echo_server.close(iter->second->gethdl(),websocketpp::close::status::going_away,"");
        m_connection_list.erase(iter++);
    }

    echo_server.stop_perpetual();
    m_thread->join();
}

//鏈接

void websocket_server::on_open(server *s,websocket_server* pWebSocket,websocketpp::connection_hdl hdl)
{
    server::connection_ptr con  = s->get_con_from_hdl(hdl);
    const std::string strRemote = con->get_remote_endpoint();
    con_list::iterator iter = pWebSocket->m_connection_list.find(strRemote);

    if(iter == pWebSocket->m_connection_list.end())
    {
        connection_metadata* pmetadata = new connection_metadata(hdl,strRemote);
        pWebSocket->m_connection_list.insert(make_pair(strRemote,pmetadata));
    }
    else
    {
        iter->second->sethdl(hdl);
    }
}

//斷開
void websocket_server::on_close(server* s,websocket_server* pWebSocket,websocketpp::connection_hdl hdl)
{
    server::connection_ptr con  = s->get_con_from_hdl(hdl);
    const std::string strRemote = con->get_remote_endpoint();
    con_list::iterator iter = pWebSocket->m_connection_list.find(strRemote);

    if(iter != pWebSocket->m_connection_list.end())
    {
        pWebSocket->m_connection_list.erase(iter);
    }
}

//通訊
void websocket_server::on_message(server* s,websocket_server* pWebSocket,websocketpp::connection_hdl hdl, message_ptr msg)
{
    if(msg->get_opcode() == websocketpp::frame::opcode::text)
    {
        server::connection_ptr con  = s->get_con_from_hdl(hdl);
        const std::string strRemote = con->get_remote_endpoint();
　　　　 std::cout << strRemote <<std::endl;
    }

    std::cout << "on_message called with hdl: " << hdl.lock().get() << " and message: " << msg->get_payload() << std::endl;

    if(msg->get_payload() == "stop-listening")
    {
        s->stop_listening();
        return;
    }

    try
    {
        s->send(hdl, msg->get_payload(),msg->get_opcode());//接收到的數據原路返回
    }

    catch (const websocketpp::lib::error_code& e)
    {
        std::cout << "Echo failed because: " << e << "(" << e.message() << ")" << std::endl;
    }
}

void websocket_server::start(int port)
{
    try
    {
        // Set logging settings
        echo_server.set_access_channels(websocketpp::log::alevel::all);
        echo_server.clear_access_channels(websocketpp::log::alevel::frame_payload);

        // Initialize Asio
        echo_server.init_asio();
        echo_server.start_perpetual();

        echo_server.set_open_handler(bind(&on_open,&echo_server,this,::_1));
        echo_server.set_close_handler(bind(&on_close,&echo_server,this,::_1));
        echo_server.set_message_handler(bind(&on_message,&echo_server,this,::_1,::_2));

        // Listen on port 9002
        echo_server.listen(port);

        // Start the server accept loop
        echo_server.start_accept();

        // Start the ASIO io_service run loop        //echo_server.run();        m_thread = websocketpp::lib::make_shared<websocketpp::lib::thread>(&server::run,&echo_server);//用線程m_thread的run函數來跑echo_server的run，這樣能夠避免程序卡在echo_server的run裏    }    catch (websocketpp::exception const & e)    {        std::cout << e.what() << std::endl;    }    catch (...)    {        std::cout << "other exception" << std::endl;    }}