Method grab_url

dlib/http_client/http_client.cpp:486–721

// ----------------------------------------------------------------------------------------

    bool http_client::grab_url(const std::string& url, const std::string& method, const std::string& post_body)
    {
        error_field.clear();
        returned_headers.clear();
        http_return = 0;
        returned_body.clear();

        std::string to_use_method = strtoupper(method);

        std::string scheme, user, pass, host, path;
        short port;
        if ( !parse_url(url, scheme, user, pass, host, port, path) )
        {
            error_field = "Couldn't parse the URL!";
            return false;
        }

        // Build request
        std::stringstream ret;
        ret << to_use_method << ' ' << path << " HTTP/1.0\r\n"
            << "Host: " << host;
        if (port != 80 && port != 443) ret << ':' << port;
        ret << "\r\n";

        bool content_length_said = false;

        set_header("Connection", "Close");
        for (stringmap::iterator ci = headers.begin(); ci != headers.end(); ++ci)
        {
            std::string head = strtolower(ci->first);

            if ( head == "content-length" )
            {
                content_length_said = true;
            }

            ret << ci->first << ':' << ' ' << ci->second << "\r\n";
        }

        if ( !content_length_said && to_use_method != "GET" )
            ret << "Content-Length: " << static_cast<unsigned int>(post_body.size()) << "\r\n";

        std::stringstream cookie_ss;
        for (stringmap::iterator ci = cookies.begin(); ci != cookies.end(); ++ci)
        {
            std::string var = ci->first ; trim(var);
            std::string val = ci->second; trim(val);

            if ( val.empty() || var.empty() )
                continue;

            if ( !cookie_ss.str().empty() )
                cookie_ss << ';' << ' ';

            cookie_ss << urlencode(var) << '=' << urlencode(val);
        }

        if ( !cookie_ss.str().empty() )