RequestParser.cpp

Go to the documentation of this file.

/*
 * SNode.C - a slim toolkit for network communication
 * Copyright (C) Volker Christian <me@vchrist.at>
 *               2020, 2021, 2022, 2023, 2024, 2025
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published
 * by the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
 
#include "web/http/server/RequestParser.h"
 
#ifndef DOXYGEN_SHOULD_SKIP_THIS
 
#include "web/http/http_utils.h"
 
#include <regex>
#include <tuple>
#include <utility>
 
#endif /* DOXYGEN_SHOULD_SKIP_THIS */
 
namespace web::http::server {
 
    RequestParser::RequestParser(core::socket::stream::SocketContext* socketContext,
                                 const std::function<void()>& onRequestStart,
                                 const std::function<void(Request&&)>& onRequestParsed,
                                 const std::function<void(int, const std::string&)>& onRequestParseError)
        : Parser(socketContext)
        , onRequestStart(onRequestStart)
        , onRequestParsed(onRequestParsed)
        , onRequestParseError(onRequestParseError) {
    }
 
    bool RequestParser::methodSupported(const std::string& method) const {
        return supportedMethods.contains(method);
    }
 
    void RequestParser::begin() {
        onRequestStart();
    }
 
    void RequestParser::parseStartLine(const std::string& line) {
        parserState = Parser::ParserState::HEADER;
 
        if (!line.empty()) {
            std::string remaining;
 
            std::tie(request.method, remaining) = httputils::str_split(line, ' ');
            std::tie(request.url, request.httpVersion) = httputils::str_split(remaining, ' ');
 
            std::string queriesLine;
            std::tie(std::ignore, queriesLine) = httputils::str_split(request.url, '?');
 
            if (!methodSupported(request.method)) {
                parseError(400, "Bad request method: " + request.method);
            } else if (request.url.empty() || request.url.front() != '/') {
                parseError(400, "Malformed request");
            } else {
                std::smatch httpVersionMatch;
                if (!std::regex_match(request.httpVersion, httpVersionMatch, httpVersionRegex)) {
                    parseError(400, "Wrong protocol-version: " + request.httpVersion);
                } else {
                    httpMajor = std::stoi(httpVersionMatch.str(1));
                    httpMinor = std::stoi(httpVersionMatch.str(2));
 
                    while (!queriesLine.empty()) {
                        std::string query;
 
                        std::tie(query, queriesLine) = httputils::str_split(queriesLine, '&');
                        request.queries.insert(httputils::str_split(query, '='));
                    }
                }
            }
        } else {
            parseError(400, "Request-line empty");
        }
    }
 
    void RequestParser::analyzeHeader() {
        Parser::analyzeHeader();
 
        if (headers.contains("Connection")) {
            const std::string& connection = headers["Connection"];
            if (web::http::ciContains(connection, "keep-alive")) {
                request.connectionState = ConnectionState::Keep;
            } else if (web::http::ciContains(connection, "close")) {
                request.connectionState = ConnectionState::Close;
            }
        }
 
        if (headers.contains("Cookie")) {
            std::string& cookiesLine = headers["Cookie"];
 
            while (!cookiesLine.empty()) {
                std::string cookieLine;
                std::tie(cookieLine, cookiesLine) = httputils::str_split(cookiesLine, ',');
 
                while (!cookieLine.empty()) {
                    std::string cookie;
                    std::tie(cookie, cookieLine) = httputils::str_split(cookieLine, ';');
 
                    std::string cookieName;
                    std::string cookieValue;
                    std::tie(cookieName, cookieValue) = httputils::str_split(cookie, '=');
 
                    httputils::str_trimm(cookieName);
                    httputils::str_trimm(cookieValue);
 
                    request.cookies.emplace(cookieName, cookieValue);
                }
            }
 
            headers.erase("Cookie");
        }
 
        if (transferEncoding != TransferEncoding::Chunked && contentLength == 0) {
            parsingFinished();
        } else {
            parserState = Parser::ParserState::BODY;
        }
    }
 
    void RequestParser::parsingFinished() {
        request.httpMajor = httpMajor;
        request.httpMinor = httpMinor;
        request.headers = std::move(Parser::headers);
        request.body = std::move(content);
 
        onRequestParsed(std::move(request));
 
        reset();
 
        parserState = ParserState::BEGIN;
    }
 
    void RequestParser::parseError(int code, const std::string& reason) {
        onRequestParseError(code, reason);
 
        reset();
 
        parserState = ParserState::ERROR;
    }
 
} // namespace web::http::server