C++实现websocket服务端客户端(基于boost，亲测可行！)

曾经终败给现在 2023-10-12 16:10 20阅读 0赞

**整篇文章基本参考了[https://blog.csdn.net/jianghuan0122/article/details/123528907][https_blog.csdn.net_jianghuan0122_article_details_123528907]，文章记录了如何在现有条件下实现该参考示例(参考示例存在报错，并且参考示例没有介绍环境安装，正确源码附于文末)**

自身环境：ubuntu18.04+gcc7.5.0+boost1.7,3

### 环境配置 ###

gcc或者g++一般都有，这里主要介绍一下boost的配置方法  
  执行如下代码：

wget https://boostorg.jfrog.io/artifactory/main/release/1.73.0/source/boost_1_73_0.tar.bz2 --no-check-certificate
    tar xvf boost_1_73_0.tar.bz2
    cd boost_1_73_0
    ./bootstrap.sh --prefix=/usr 
    ./b2 
    sudo ./b2 install
    cat /usr/include/boost/version.hpp | grep "BOOST_LIB_VERSION"

装完后发现还是会报错：\#include ＜boost/beast/core.hpp＞ no such file  
  这个时候再加一个：

sudo apt-get install libboost-all-dev

然后编译执行代码就可以了，在这里说明下我不太确定是否要执行那个apt-get，理论上前面是源码编译就没问题了，后面估计是默认库的安装，但是我当时没太注意顺序，两个都做了一下才成功、  
**boost安装参考**：[https://blog.csdn.net/HandsomeHong/article/details/128813619][https_blog.csdn.net_HandsomeHong_article_details_128813619]

还有就是参考的示例存在报错，是关于C++11codecvt部分的，没有时间去改bug了，就直接换了一套string和wstring的相互转化，主要参考了：[https://blog.csdn.net/juluwangriyue/article/details/115680861][https_blog.csdn.net_juluwangriyue_article_details_115680861]  
  这个需要加两个头文件\#include <wchar.h> \#include <locale.h>

### 示例源码 ###

#### server.cpp(需要换自己的IP) ####

#include <boost/beast/core.hpp>
    #include <boost/beast/websocket.hpp>
    #include <boost/asio/ip/tcp.hpp>
    #include <cstdlib>
    #include <functional>
    #include <iostream>
    #include <string>
    #include <thread>
    #include <codecvt>
    #include <wchar.h>
    #include <locale.h>
    namespace beast = boost::beast;         // from <boost/beast.hpp>
    namespace http = beast::http;           // from <boost/beast/http.hpp>
    namespace websocket = beast::websocket; // from <boost/beast/websocket.hpp>
    namespace net = boost::asio;            // from <boost/asio.hpp>
    using tcp = boost::asio::ip::tcp;       // from <boost/asio/ip/tcp.hpp>
    std::wstring string_to_wstring(const std::string& str)
    {
        
    	std::wstring r;
        const char *source = str.c_str();
        wchar_t *dest = NULL;
        int len = 0;
        int ret = 0;
        len = strlen(source) + 1;
        if(len <= 1)
            return 0;
        dest = new wchar_t[len];
        ret = mbstowcs(dest, source, len);
        r = std::wstring(dest);
        delete[] dest;
    	return r;
    }
    
    std::string wstring_to_string(const std::wstring& ws)
    {
        
    	std::string r = "";
        const wchar_t *source = ws.c_str();
        char *dest = NULL;
        int len = 0;
        int ret = 0;
        len = wcslen(source) + 1;
        if(len <= 1)
            return 0;
        dest = new char[len*sizeof(wchar_t)];
        ret = wcstombs(dest, source, len*sizeof(wchar_t));
        r = std::string(dest);
        delete[] dest;
    	return r;
    }
    
    std::string ansi_to_utf8(const std::string& s)
    {
        
    	static std::wstring_convert<std::codecvt_utf8<wchar_t> > conv;
    	return conv.to_bytes(string_to_wstring(s));
    }
    std::string utf8_to_ansi(const std::string& s)
    {
        
    	static std::wstring_convert<std::codecvt_utf8<wchar_t> > conv;
    	return wstring_to_string(conv.from_bytes(s));
    }
     
    void do_session(tcp::socket& socket)
    {
        
    	try
    	{
        
    		websocket::stream<tcp::socket> ws{
         std::move(socket) };
    		ws.set_option(websocket::stream_base::decorator(
    			[](websocket::response_type& res)
    		{
        
    			res.set(http::field::server,
    				std::string(BOOST_BEAST_VERSION_STRING) +
    				" websocket-server-sync");
    		}));
    		ws.accept();//等待客户端连接
    		for (;;)
    		{
        
    			std::string text = "{\"send\": 123}"; // 发送的消息内容，以一个json数据包的格式	
    			ws.write(net::buffer(ansi_to_utf8(text)));// 发送消息
    		
    			beast::flat_buffer buffer;// 这个缓冲区将保存传入的消息
    			ws.read(buffer);// 读取一条消息
    			auto out = beast::buffers_to_string(buffer.cdata());
    			std::cout << utf8_to_ansi(out) << std::endl;
     
    			sleep(1); //等待1秒
     
    			/*
    			// 将读取到的消息再发送回客户端
    			ws.text(ws.got_text());
    			ws.write(buffer.data());
    			*/
    		}
    	}
    	catch (beast::system_error const& se)
    	{
        
    		if (se.code() != websocket::error::closed)
    			std::cerr << "Error: " << se.code().message() << std::endl;
    	}
    	catch (std::exception const& e)
    	{
        
    		std::cerr << "Error: " << e.what() << std::endl;
    	}
    }
     
    int main(int argc, char* argv[])
    {
        
    	try
    	{
        
    		auto const address = net::ip::make_address("192.168.1.116");//绑定ip地址
    		auto const port = static_cast<unsigned short>(std::atoi("20000"));//绑定端口号
    		net::io_context ioc{
         1 };
    		tcp::acceptor acceptor{
         ioc,{
         address, port } };
    		for (;;)
    		{
        
    			tcp::socket socket{
         ioc };
    			acceptor.accept(socket);
    			// 开启线程等待客户端的连接请求
    			std::thread{
         std::bind(&do_session,std::move(socket)) }.detach();
    		}
    	}
    	catch (const std::exception & e)
    	{
        
    		std::cerr << "Error: " << e.what() << std::endl;
    		return EXIT_FAILURE;
    	}
    }

#### client.cpp(需要换自己的IP) ####

#include<time.h> 
     
    #include <boost/beast/core.hpp>
    #include <boost/beast/websocket.hpp>
    #include <boost/asio/connect.hpp>
    #include <boost/asio/ip/tcp.hpp>
    #include <cstdlib>
    #include <iostream>
    #include <string>
    #include <locale>
    #include <codecvt>
    #include <wchar.h>
    #include <locale.h>
    namespace beast = boost::beast;         // from <boost/beast.hpp>
    namespace http = beast::http;           // from <boost/beast/http.hpp>
    namespace websocket = beast::websocket; // from <boost/beast/websocket.hpp>
    namespace net = boost::asio;            // from <boost/asio.hpp>
    using tcp = boost::asio::ip::tcp;       // from <boost/asio/ip/tcp.hpp>
    std::wstring string_to_wstring(const std::string& str)
    {
        
    	std::wstring r;
        const char *source = str.c_str();
        wchar_t *dest = NULL;
        int len = 0;
        int ret = 0;
        len = strlen(source) + 1;
        if(len <= 1)
            return 0;
        dest = new wchar_t[len];
        ret = mbstowcs(dest, source, len);
        r = std::wstring(dest);
        delete[] dest;
    	return r;
    }
    
    std::string wstring_to_string(const std::wstring& ws)
    {
        
    	std::string r = "";
        const wchar_t *source = ws.c_str();
        char *dest = NULL;
        int len = 0;
        int ret = 0;
        len = wcslen(source) + 1;
        if(len <= 1)
            return 0;
        dest = new char[len*sizeof(wchar_t)];
        ret = wcstombs(dest, source, len*sizeof(wchar_t));
        r = std::string(dest);
        delete[] dest;
    	return r;
    }
    
    std::string ansi_to_utf8(const std::string &s)
    {
        
    	static std::wstring_convert<std::codecvt_utf8<wchar_t> > conv;
    	return conv.to_bytes(string_to_wstring(s));
    }
    std::string utf8_to_ansi(const std::string& s)
    {
        
    	static std::wstring_convert<std::codecvt_utf8<wchar_t> > conv;
    	return wstring_to_string(conv.from_bytes(s));
    }
     
    int main(int argc, char** argv)
    {
        
    	int num = 0;//接收到包的个数
     
    	try
    	{
        
    		net::io_context ioc;
    		tcp::resolver resolver{
         ioc };
    		websocket::stream<tcp::socket> ws{
         ioc };
    		auto const address = net::ip::make_address("192.168.1.116"); //服务器地址
    		auto const port = static_cast<unsigned short>(std::atoi("20000"));//服务器端口号
    		tcp::endpoint endpoint{
         address, port };
    		auto const results = resolver.resolve(endpoint);
    		// 在我们从查找中获得的IP地址上建立连接
    		net::connect(ws.next_layer(), results.begin(), results.end());
    		ws.set_option(websocket::stream_base::decorator(
    			[](websocket::request_type& req)
    		{
        
    			req.set(http::field::user_agent,
    				std::string(BOOST_BEAST_VERSION_STRING) +
    				" websocket-client-coro");
    		}));
     
    		ws.handshake("192.168.1.116", "/"); //发送握手消息
    		while (true)
    		{
        
    			beast::flat_buffer buffer;//创建一个缓冲区用于存放接收到的消息	
    			ws.read(buffer);// 读取一条消息到缓冲区
    			std::string out;
    			out = beast::buffers_to_string(buffer.cdata());
    			std::cout << utf8_to_ansi(out) << std::endl; //输出消息到控制台显示
     
    			//解析json数据包
    			if (out != "") //未解析json，只是判断内容是否为空
    			{
        		
    				std::string text = "{\"result\": 0}";//发送的消息内容，以一个json数据包的格式
    				ws.write(net::buffer(ansi_to_utf8(text))); // 发送消息
     
    				num++;//增加计数
     
    				//当前时间
    				time_t now = time(NULL);
    				tm* tm_t = localtime(&now);
    				std::stringstream ss;
    				ss << tm_t->tm_year + 1900 << "-" << tm_t->tm_mon + 1 << "-" << tm_t->tm_mday
    					<< " " << tm_t->tm_hour << ":" << tm_t->tm_min << ":" << tm_t->tm_sec;
     
    				std::cout << "当前时间：" << ss.str() << "，第 " << num << "个"<<std::endl;
    			}			
    		}
    	
    		ws.close(websocket::close_code::normal);// 关闭WebSocket连接
    	}
    	catch (std::exception const& e)
    	{
        
    		std::cerr << "Error: " << e.what() << std::endl;
    		return EXIT_FAILURE;
    	}
    	return EXIT_SUCCESS;
    }

编译的命令如下：

g++ server.cpp -o server -lpthread -std=c++11
    g++ client.cpp -o client -std=c++11 -lpthread

[https_blog.csdn.net_jianghuan0122_article_details_123528907]: https://blog.csdn.net/jianghuan0122/article/details/123528907
[https_blog.csdn.net_HandsomeHong_article_details_128813619]: https://blog.csdn.net/HandsomeHong/article/details/128813619
[https_blog.csdn.net_juluwangriyue_article_details_115680861]: https://blog.csdn.net/juluwangriyue/article/details/115680861