gpt4 book ai didi

c++ - 如何使用 Beast C++ 库从 HTTP 重定向到 HTTPS?

转载 作者:塔克拉玛干 更新时间:2023-11-03 00:23:06 27 4
gpt4 key购买 nike

我正在研究 Boost.Beast 库。我尝试提出一个请求,其响应是:

HTTP/1.1 301 Moved Permanently
Cache-Control: public
Content-Type: text/html; charset=UTF-8
Location: https://www.example.com/target/xxx/

然后,我尝试使用此位置字段发出请求,但收到错误的请求响应。

如何进行重定向?有例子吗?

这是我的代码:

boost::asio::io_service ios;
tcp::resolver resolver{ios};
tcp::socket socket{ios};
auto const lookup = resolver.resolve( tcp::resolver::query(host, port) );
boost::asio::connect(socket, lookup);

// Set up an HTTP GET request message
http::request<http::string_body> req{http::verb::get, target, 11};
req.set(http::field::host, host);
req.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING);

// Send the HTTP request to the remote host
http::write(socket, req);

// This buffer is used for reading and must be persisted
boost::beast::flat_buffer buffer;

// Declare a container to hold the response
http::response<http::dynamic_body> res;

// Receive the HTTP response
http::read(socket, buffer, res);

if( res.base().result_int() == 301 ) {
req.set(http::field::location, res.base()["Location"]);
http::write(socket, req);
boost::beast::flat_buffer buffer1;
http::read(socket, buffer1, res);
}
std::cout << req << std::endl;
std::cout << res << std::endl;

谢谢

最佳答案

当您重定向时,您不能只是“替换”现有请求中的位置。您甚至不能使用相同的套接字,除非在极少数情况下重定向的目标位于相同的 TCP 端点上。

因为主机名、协议(protocol)和路径可能已经改变,你必须解析位置,获取方案、主机、路径部分。然后您必须再次进行正确的主机解析,并确保在 Host header 中使用正确的主机名。

这是一个示例,显示在“错误”的 url http://boost.org/user/license.html 请求 Boost 许可证,它将立即重定向到 http://www.boost.org/user/license.html

NOTE I've used network::uri to do the URI parsing for us: https://github.com/reBass/uri

演示

#include <iostream>
#include <boost/beast.hpp>
#include <boost/beast/http.hpp>
#include <network/uri.hpp>
#include <boost/asio.hpp>
#include <string>

using boost::asio::ip::tcp;
namespace http = boost::beast::http;

struct Requester {
void do_request(std::string const& url) {
network::uri u{url};
auto const lookup = resolver_.resolve( tcp::resolver::query(u.host().to_string(), u.scheme().to_string()) );

// Set up an HTTP GET request message
tcp::socket socket{ios};
boost::asio::connect(socket, lookup);

http::request<http::string_body> req{http::verb::get, u.path().to_string(), 11};
req.keep_alive(true);

req.set(http::field::host, u.host().to_string());
req.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING);

std::cout << "Target: " << url << "\n";
std::cout << req << "\n";

http::write(socket, req);
boost::beast::flat_buffer buffer;
http::response<http::dynamic_body> res;
http::read(socket, buffer, res);

switch(res.base().result_int()) {
case 301:
std::cout << "Redirecting.....\n";
do_request(res.base()["Location"].to_string());
break;
case 200:
std::cout << res << "\n";
break;
default:
std::cout << "Unexpected HTTP status " << res.result_int() << "\n";
break;
}
}
private:
boost::asio::io_service ios;
tcp::resolver resolver_{ios};
};

int main() {
try {
Requester requester;
requester.do_request("http://boost.org/users/license.html"); // redirects to http://www.boost.org/...
} catch(std::exception const& e) {
std::cerr << "Exception: " << e.what() << "\n";
}
}

这打印:

Target: http://boost.org/users/license.html
GET /users/license.html HTTP/1.1
Host: boost.org
User-Agent: Boost.Beast/109


Redirecting.....
Target: http://www.boost.org/users/license.html
GET /users/license.html HTTP/1.1
Host: www.boost.org
User-Agent: Boost.Beast/109


HTTP/1.1 200 OK
Date: Sun, 27 Aug 2017 22:25:20 GMT
Server: Apache/2.2.15 (CentOS)
Accept-Ranges: bytes
Connection: close
Transfer-Encoding: chunked
Content-Type: text/html

90fd
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<title>Boost Software License</title>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii" />
<link rel="icon" href="/favicon.ico" type="image/ico" />
<link rel="stylesheet" type="text/css" href="../style-v2/section-boost.css" />
<!--[if IE 7]> <style type="text/css"> body { behavior: url(/style-v2/csshover3.htc); } </style> <![endif]-->
</head><!--
Note: Editing website content is documented at:
http://www.boost.org/development/website_updating.html
-->

<body>
ENTIRE LICENSE BODY SNIPPED
</body>
</html>

0

关于c++ - 如何使用 Beast C++ 库从 HTTP 重定向到 HTTPS?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/45880254/

27 4 0
Copyright 2021 - 2024 cfsdn All Rights Reserved 蜀ICP备2022000587号
广告合作:1813099741@qq.com 6ren.com