我之前发布了一个问题,询问为什么我的服务器(C++和boost::asio
编写)无法与客户端(Javascript编写)建立连接。问题出在Javascript Websockets和boost::asio
sockets的不同吗?boost::asio
是否不支持Websockets?最简单的解决方法是什么?
我之前发布了一个问题,询问为什么我的服务器(C++和boost::asio
编写)无法与客户端(Javascript编写)建立连接。问题出在Javascript Websockets和boost::asio
sockets的不同吗?boost::asio
是否不支持Websockets?最简单的解决方法是什么?
Boost.Beast现在是Boost库的一部分,它是在Boost.Asio之上构建的,并按照您的期望方式工作。它附带示例代码和文档。在这里查看:www.boost.org/libs/beast
这是一个完整的程序,向回显服务器发送一条消息:
#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>
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>
// Sends a WebSocket message and prints the response
int main(int argc, char** argv)
{
try
{
// Check command line arguments.
if(argc != 4)
{
std::cerr <<
"Usage: websocket-client-sync <host> <port> <text>\n" <<
"Example:\n" <<
" websocket-client-sync echo.websocket.org 80 \"Hello, world!\"\n";
return EXIT_FAILURE;
}
std::string host = argv[1];
auto const port = argv[2];
auto const text = argv[3];
// The io_context is required for all I/O
net::io_context ioc;
// These objects perform our I/O
tcp::resolver resolver{ioc};
websocket::stream<tcp::socket> ws{ioc};
// Look up the domain name
auto const results = resolver.resolve(host, port);
// Make the connection on the IP address we get from a lookup
auto ep = net::connect(ws.next_layer(), results);
// Update the host_ string. This will provide the value of the
// Host HTTP header during the WebSocket handshake.
// See https://tools.ietf.org/html/rfc7230#section-5.4
host += ':' + std::to_string(ep.port());
// Set a decorator to change the User-Agent of the handshake
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");
}));
// Perform the websocket handshake
ws.handshake(host, "/");
// Send the message
ws.write(net::buffer(std::string(text)));
// This buffer will hold the incoming message
beast::flat_buffer buffer;
// Read a message into our buffer
ws.read(buffer);
// Close the WebSocket connection
ws.close(websocket::close_code::normal);
// If we get here then the connection is closed gracefully
// The make_printable() function helps print a ConstBufferSequence
std::cout << beast::make_printable(buffer.data()) << std::endl;
}
catch(std::exception const& e)
{
std::cerr << "Error: " << e.what() << std::endl;
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
req.set(http::field::user_agent, std::string(BOOST_BEAST_VERSION_STRING) + " websocket-client-coro");
? - user997112
boost::asio
传输。目前来看,你需要在asio
之上编写自己的websocket协议代码,或者使用像websocket++这样的现有库。 - Sean ClineWesocketpp
完美地工作了。谢谢。这绝对是在 C++ 中使用 Websockets 最简单的方法。首先安装boost
,然后将Websocketpp
作为一个仅包含头文件的库添加到项目中。 - dimitris93