有没有一种方法可以解析来自字符串的HTTP请求并使用POCO获取其主体？

Question

I have a pretty old server application written in C++ which I have to support and develop. Its code history consists of more than 15 years of development. Most of the code is written manually, including net parts. There are many other parts which reinvent the wheel, eg Unicode support, etc.

My main goal is to gradually substitute bug-prone wheel-ish parts of code with some well designed and supported open source alternatives as a background refactoring process. Net code is priority. But I can't do it in one step.

Currently what I need is the ability to parse an HTTP request from string. I don't need to send or receive data, the old code does it and I need to integrate with it - at least for now. I need to read various headers, get URI and parse it - including query parameters.

The part I'm having trouble with is to get the request body. There is not way to achieve that with the HTTPRequest class. I see a method called stream() in the HTTPServerRequestImpl class, but that class seems to be some internal stuff for the HTTPServer - there is no way to construct it without a session, a socket and some params.

The problem is - I don't need to make network requests with POCO, at least for now. There are several other libraries which can solve my current tasks (httpxx, cpp-netlib) each with their own missing functionality, but it would be really great to integrate POCO from early stages, because it seems quite versatile, robust and can replace (I think) all manually-written old code in the near future. There is of course the way to just separate the request by new lines, but I would really prefer some POCO standard tool if it exists.

Here is my test project code (with some test HTTP data) for POCO, maybe it will help someone or give a better idea how I want to use the library:

#include <sstream>
#include <iostream>

#include <Poco/Net/HTTPRequest.h>
#include <Poco/URI.h>

int main()
{
    std::stringstream str;
    str <<
        "POST http://www.example.com/ajax/gw-light.php?api_version=1.0&api_token=1111&input=3&cid=23232 HTTP/1.1\n"
        "Host: www.example.com\n"
        "User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:48.0) Gecko/20100101 Firefox/48.0\n"
        "Accept: */*\n"
        "Accept-Language: en-US,en;q=0.7,uk;q=0.3\n"
        "Accept-Encoding: gzip, deflate\n"
        "Content-Type: text/plain;charset=UTF-8\n"
        "Origin: http://www.example.com\n"
        "Referer: http://www.example.com/album/10658860\n"
        "Content-Length: 331\n"
        "Cookie: __qca=dsgsfdgds; __utma=1234534543.5654604.1452342360.14123253.146543.84\n"
        "Connection: keep-alive\n"
        "\n"
        "[{\"method\":\"log.listen\",\"params\":{\"params\":{\"media\":{\"id\":\"72192840\",\"type\":\"song\"},\"type\":0,\"stat\":{\"seek\":0,\"pause\":0},\"lt\":235,\"ctxt\":{\"t\":\"artist_discography\",\"id\":7094080},\"payload\":{},\"dev\":{\"v\":\"00350497\",\"t\":0},\"ls\":[],\"ts_listen\":1472135022,\"timestamp\":1472747105},\"next_media\":{\"media\":{\"id\":\"72192841\",\"type\":\"song\"}}}}]\n";

    Poco::Net::HTTPRequest req;
    req.read( str );

    std::cout << "Host: " << req.getHost() << "\nMethod: " << req.getMethod() <<
            "\nUser-Agent: " << req.get( "User-Agent" ) << "\nURI: " << req.getURI() << std::endl;

    Poco::Net::NameValueCollection cookies;
    req.getCookies( cookies );
    for( auto curCookieIt = cookies.begin(); curCookieIt != cookies.end(); ++curCookieIt )
        std::cout << "Cookie: " << curCookieIt->first << "\n\tValue: " << curCookieIt->second << std::endl;

    Poco::URI uri( req.getURI() );
    auto params = uri.getQueryParameters();
    for( auto curParamIt = params.cbegin(); curParamIt != params.cend(); ++curParamIt )
        std::cout << curParamIt->first << " : " << curParamIt->second << std::endl;

    return 0;
}

Answer 1

HTTPRequest object knows nothing about body of request. So you can't get this information from HTTPRequest. If need send the request body use HTTPClientSession . From documentation:

To send a HTTP request to a HTTP server, first instantiate a HTTPClientSession object and specify the server's host name and port number. Then create a HTTPRequest object, fill it accordingly, and pass it as argument to the sendRequst() method. sendRequest() will return an output stream that can be used to send the request body, if there is any. After you are done sending the request body, create a HTTPResponse object and pass it to receiveResponse(). This will return an input stream that can be used to read the response body.