摘要：
教程：一组示例程序的详细演练。Websocketpp：所有库代码和默认配置文件。WebSocket++是一个仅包含头文件的库。您可以开始使用它，方法是在项目的包含路径中包含websocketpp源目录，并在程序中包含适当的WebSocket++头文件。您可能还需要包含和/或链接到相应的Boost/系统库。examples_Server下有echo，echo_Client通常用作入门示例。接下来，在Windows上运行此示例。
websocketpp
https://github.com/zaphoyd/websocketpp
https://docs.websocketpp.org/getting_started.html
仓库包含如下几个目录：
- docs: 文档
- examples: 示例程序演示如何为WebSocket客户端和服务器构建一些常用模式的基本版本。
- test: 单元测试确认您的代码正常工作，并帮助检测平台特定的问题。
- tutorials: 一组示例程序的详细演练。
- websocketpp: 所有库代码和默认配置文件。
WebSocket ++是仅包含头文件的库。您可以通过在项目的包含路径中包含websocketpp源目录，并在程序中包含适当的WebSocket++头文件，来开始使用它。您可能还需要包含和/或链接到适当的Boost/系统库。
在examples下有echo_server和echo_client，一般作为入门的例子。
下面在Windows上来运行这个例子。
首先，下载boost：https://www.boost.org/users/download/
接下来编译boost：
打开命令行，运行bootstrap.bat
接下来运行b2.exe
不出意外的话，就编好了（我这里都是默认配置来编译的，使用的是VS2019）
VS2019中新建websocketpp_server console
删掉main.cpp，将echo_server.cpp拷贝过来加入到工程中去
VS2019中新建websocketpp_client console
删掉main.cpp，将echo_client.cpp拷贝过来加入到工程中去
工程设置：
Include路径：
D:GitWorkoost_1_72_0
D:GitWorkwebsocketpp-master
Lib路径：
D:GitWorkoost_1_72_0stagelib
链接libboost_date_time-vc142-mt-gd-x64-1_72.lib
Debug x64配置构建运行：
可以使用在线WebSocket网站进行测试
服务端收到信息：
如果要在Qt中使用，可参考以下pro配置：
QT -= gui CONFIG += c++11 console CONFIG -= app_bundle DEFINES += QT_DEPRECATED_WARNINGS # Default rules for deployment. qnx: target.path = /tmp/$${TARGET}/bin else: unix:!android: target.path = /opt/$${TARGET}/bin !isEmpty(target.path): INSTALLS += target HEADERS += echo_handler.hpp # 没用到，里面内容可注释掉 SOURCES += echo_server.cpp win32: LIBS += -L$$PWD/../../../boost_1_72_0/stage/lib/ -llibboost_date_time-vc142-mt-gd-x64-1_72 win32: LIBS += -lWs2_32 -lwsock32 INCLUDEPATH += $$PWD/../../ INCLUDEPATH += $$PWD/../../../boost_1_72_0 DEPENDPATH += $$PWD/../../../boost_1_72_0/stage
关于主动发送信息，可以使用send方法，可以开一个线程，如果有内容，就发送，broadcast_server可以参考一下：
#include <websocketpp/config/asio_no_tls.hpp> #include <websocketpp/server.hpp> #include <iostream> #include <set> /*#include <boost/thread.hpp> #include <boost/thread/mutex.hpp> #include <boost/thread/condition_variable.hpp>*/ #include <websocketpp/common/thread.hpp> typedef websocketpp::server<websocketpp::config::asio> server; using websocketpp::connection_hdl; using websocketpp::lib::placeholders::_1; using websocketpp::lib::placeholders::_2; using websocketpp::lib::bind; using websocketpp::lib::thread; using websocketpp::lib::mutex; using websocketpp::lib::lock_guard; using websocketpp::lib::unique_lock; using websocketpp::lib::condition_variable; /* on_open insert connection_hdl into channel * on_close remove connection_hdl from channel * on_message queue send to all channels */ enum action_type { SUBSCRIBE, UNSUBSCRIBE, MESSAGE }; struct action { action(action_type t, connection_hdl h) : type(t), hdl(h) {} action(action_type t, connection_hdl h, server::message_ptr m) : type(t), hdl(h), msg(m) {} action_type type; websocketpp::connection_hdl hdl; server::message_ptr msg; }; class broadcast_server { public: broadcast_server() { // Initialize Asio Transport m_server.init_asio(); // Register handler callbacks m_server.set_open_handler(bind(&broadcast_server::on_open,this,::_1)); m_server.set_close_handler(bind(&broadcast_server::on_close,this,::_1)); m_server.set_message_handler(bind(&broadcast_server::on_message,this,::_1,::_2)); } void run(uint16_t port) { // listen on specified port m_server.listen(port); // Start the server accept loop m_server.start_accept(); // Start the ASIO io_service run loop try { m_server.run(); } catch (const std::exception & e) { std::cout << e.what() << std::endl; } } void on_open(connection_hdl hdl) { { lock_guard<mutex> guard(m_action_lock); //std::cout << "on_open" << std::endl; m_actions.push(action(SUBSCRIBE,hdl)); } m_action_cond.notify_one(); } void on_close(connection_hdl hdl) { { lock_guard<mutex> guard(m_action_lock); //std::cout << "on_close" << std::endl; m_actions.push(action(UNSUBSCRIBE,hdl)); } m_action_cond.notify_one(); } void on_message(connection_hdl hdl, server::message_ptr msg) { // queue message up for sending by processing thread { lock_guard<mutex> guard(m_action_lock); //std::cout << "on_message" << std::endl; m_actions.push(action(MESSAGE,hdl,msg)); } m_action_cond.notify_one(); } void process_messages() { while(1) { unique_lock<mutex> lock(m_action_lock); while(m_actions.empty()) { m_action_cond.wait(lock); } action a = m_actions.front(); m_actions.pop(); lock.unlock(); if (a.type == SUBSCRIBE) { lock_guard<mutex> guard(m_connection_lock); m_connections.insert(a.hdl); } else if (a.type == UNSUBSCRIBE) { lock_guard<mutex> guard(m_connection_lock); m_connections.erase(a.hdl); } else if (a.type == MESSAGE) { lock_guard<mutex> guard(m_connection_lock); con_list::iterator it; for (it = m_connections.begin(); it != m_connections.end(); ++it) { m_server.send(*it,a.msg); } } else { // undefined. } } } private: typedef std::set<connection_hdl,std::owner_less<connection_hdl> > con_list; server m_server; con_list m_connections; std::queue<action> m_actions; mutex m_action_lock; mutex m_connection_lock; condition_variable m_action_cond; }; int main() { try { broadcast_server server_instance; // Start a thread to run the processing loop thread t(bind(&broadcast_server::process_messages,&server_instance)); // Run the asio loop with the main thread server_instance.run(9002); t.join(); } catch (websocketpp::exception const & e) { std::cout << e.what() << std::endl; } }