qBittorrent/src/base/rss/private/rssparser.cpp
Vladimir Golovnev (Glassez) 6662081044 Improve RSS parsing logic.
2016-01-04 06:59:07 +03:00

467 lines
17 KiB
C++

/*
* Bittorrent Client using Qt and libtorrent.
* Copyright (C) 2015 Vladimir Golovnev <glassez@yandex.ru>
* Copyright (C) 2012 Christophe Dumez <chris@qbittorrent.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* In addition, as a special exception, the copyright holders give permission to
* link this program with the OpenSSL project's "OpenSSL" library (or with
* modified versions of it that use the same license as the "OpenSSL" library),
* and distribute the linked executables. You must obey the GNU General Public
* License in all respects for all of the code used other than "OpenSSL". If you
* modify file(s), you may extend this exception to your version of the file(s),
* but you are not obligated to do so. If you do not wish to do so, delete this
* exception statement from your version.
*
* Contact : chris@qbittorrent.org
*/
#include <QDebug>
#include <QDateTime>
#include <QRegExp>
#include <QStringList>
#include <QVariant>
#include <QXmlStreamReader>
#include "rssparser.h"
namespace
{
const char shortDay[][4] = {
"Mon", "Tue", "Wed",
"Thu", "Fri", "Sat",
"Sun"
};
const char longDay[][10] = {
"Monday", "Tuesday", "Wednesday",
"Thursday", "Friday", "Saturday",
"Sunday"
};
const char shortMonth[][4] = {
"Jan", "Feb", "Mar", "Apr",
"May", "Jun", "Jul", "Aug",
"Sep", "Oct", "Nov", "Dec"
};
// Ported to Qt from KDElibs4
QDateTime parseDate(const QString &string)
{
const QString str = string.trimmed();
if (str.isEmpty())
return QDateTime::currentDateTime();
int nyear = 6; // indexes within string to values
int nmonth = 4;
int nday = 2;
int nwday = 1;
int nhour = 7;
int nmin = 8;
int nsec = 9;
// Also accept obsolete form "Weekday, DD-Mon-YY HH:MM:SS ±hhmm"
QRegExp rx("^(?:([A-Z][a-z]+),\\s*)?(\\d{1,2})(\\s+|-)([^-\\s]+)(\\s+|-)(\\d{2,4})\\s+(\\d\\d):(\\d\\d)(?::(\\d\\d))?\\s+(\\S+)$");
QStringList parts;
if (!str.indexOf(rx)) {
// Check that if date has '-' separators, both separators are '-'.
parts = rx.capturedTexts();
bool h1 = (parts[3] == QLatin1String("-"));
bool h2 = (parts[5] == QLatin1String("-"));
if (h1 != h2)
return QDateTime::currentDateTime();
}
else {
// Check for the obsolete form "Wdy Mon DD HH:MM:SS YYYY"
rx = QRegExp("^([A-Z][a-z]+)\\s+(\\S+)\\s+(\\d\\d)\\s+(\\d\\d):(\\d\\d):(\\d\\d)\\s+(\\d\\d\\d\\d)$");
if (str.indexOf(rx))
return QDateTime::currentDateTime();
nyear = 7;
nmonth = 2;
nday = 3;
nwday = 1;
nhour = 4;
nmin = 5;
nsec = 6;
parts = rx.capturedTexts();
}
bool ok[4];
const int day = parts[nday].toInt(&ok[0]);
int year = parts[nyear].toInt(&ok[1]);
const int hour = parts[nhour].toInt(&ok[2]);
const int minute = parts[nmin].toInt(&ok[3]);
if (!ok[0] || !ok[1] || !ok[2] || !ok[3])
return QDateTime::currentDateTime();
int second = 0;
if (!parts[nsec].isEmpty()) {
second = parts[nsec].toInt(&ok[0]);
if (!ok[0])
return QDateTime::currentDateTime();
}
bool leapSecond = (second == 60);
if (leapSecond)
second = 59; // apparently a leap second - validate below, once time zone is known
int month = 0;
for ( ; (month < 12) && (parts[nmonth] != shortMonth[month]); ++month);
int dayOfWeek = -1;
if (!parts[nwday].isEmpty()) {
// Look up the weekday name
while (++dayOfWeek < 7 && (shortDay[dayOfWeek] != parts[nwday]));
if (dayOfWeek >= 7)
for (dayOfWeek = 0; dayOfWeek < 7 && (longDay[dayOfWeek] != parts[nwday]); ++dayOfWeek);
}
// if (month >= 12 || dayOfWeek >= 7
// || (dayOfWeek < 0 && format == RFCDateDay))
// return QDateTime;
int i = parts[nyear].size();
if (i < 4) {
// It's an obsolete year specification with less than 4 digits
year += (i == 2 && year < 50) ? 2000 : 1900;
}
// Parse the UTC offset part
int offset = 0; // set default to '-0000'
bool negOffset = false;
if (parts.count() > 10) {
rx = QRegExp("^([+-])(\\d\\d)(\\d\\d)$");
if (!parts[10].indexOf(rx)) {
// It's a UTC offset ±hhmm
parts = rx.capturedTexts();
offset = parts[2].toInt(&ok[0]) * 3600;
int offsetMin = parts[3].toInt(&ok[1]);
if (!ok[0] || !ok[1] || offsetMin > 59)
return QDateTime();
offset += offsetMin * 60;
negOffset = (parts[1] == QLatin1String("-"));
if (negOffset)
offset = -offset;
}
else {
// Check for an obsolete time zone name
QByteArray zone = parts[10].toLatin1();
if (zone.length() == 1 && isalpha(zone[0]) && toupper(zone[0]) != 'J') {
negOffset = true; // military zone: RFC 2822 treats as '-0000'
}
else if (zone != "UT" && zone != "GMT") { // treated as '+0000'
offset = (zone == "EDT")
? -4 * 3600
: ((zone == "EST") || (zone == "CDT"))
? -5 * 3600
: ((zone == "CST") || (zone == "MDT"))
? -6 * 3600
: (zone == "MST" || zone == "PDT")
? -7 * 3600
: (zone == "PST")
? -8 * 3600
: 0;
if (!offset) {
// Check for any other alphabetic time zone
bool nonalpha = false;
for (int i = 0, end = zone.size(); (i < end) && !nonalpha; ++i)
nonalpha = !isalpha(zone[i]);
if (nonalpha)
return QDateTime();
// TODO: Attempt to recognize the time zone abbreviation?
negOffset = true; // unknown time zone: RFC 2822 treats as '-0000'
}
}
}
}
QDate qdate(year, month + 1, day); // convert date, and check for out-of-range
if (!qdate.isValid())
return QDateTime::currentDateTime();
QTime qTime(hour, minute, second);
QDateTime result(qdate, qTime, Qt::UTC);
if (offset)
result = result.addSecs(-offset);
if (!result.isValid())
return QDateTime::currentDateTime(); // invalid date/time
if (leapSecond) {
// Validate a leap second time. Leap seconds are inserted after 23:59:59 UTC.
// Convert the time to UTC and check that it is 00:00:00.
if ((hour*3600 + minute*60 + 60 - offset + 86400*5) % 86400) // (max abs(offset) is 100 hours)
return QDateTime::currentDateTime(); // the time isn't the last second of the day
}
return result;
}
}
using namespace Rss::Private;
// read and create items from a rss document
void Parser::parse(const QByteArray &feedData)
{
qDebug() << Q_FUNC_INFO;
QXmlStreamReader xml(feedData);
bool foundChannel = false;
while (xml.readNextStartElement()) {
if (xml.name() == "rss") {
// Find channels
while (xml.readNextStartElement()) {
if (xml.name() == "channel") {
parseRSSChannel(xml);
foundChannel = true;
break;
}
else {
qDebug() << "Skip rss item: " << xml.name();
xml.skipCurrentElement();
}
}
break;
}
else if (xml.name() == "feed") { // Atom feed
parseAtomChannel(xml);
foundChannel = true;
break;
}
else {
qDebug() << "Skip root item: " << xml.name();
xml.skipCurrentElement();
}
}
if (xml.hasError())
emit finished(xml.errorString());
else if (!foundChannel)
emit finished(tr("Invalid RSS feed."));
else
emit finished(QString());
}
void Parser::parseRssArticle(QXmlStreamReader &xml)
{
QVariantHash article;
while(!xml.atEnd()) {
xml.readNext();
if(xml.isEndElement() && xml.name() == "item")
break;
if (xml.isStartElement()) {
if (xml.name() == "title") {
article["title"] = xml.readElementText().trimmed();
}
else if (xml.name() == "enclosure") {
if (xml.attributes().value("type") == "application/x-bittorrent")
article["torrent_url"] = xml.attributes().value("url").toString();
}
else if (xml.name() == "link") {
QString link = xml.readElementText().trimmed();
if (link.startsWith("magnet:", Qt::CaseInsensitive))
article["torrent_url"] = link; // magnet link instead of a news URL
else
article["news_link"] = link;
}
else if (xml.name() == "description") {
article["description"] = xml.readElementText().trimmed();
}
else if (xml.name() == "pubDate") {
article["date"] = parseDate(xml.readElementText().trimmed());
}
else if (xml.name() == "author") {
article["author"] = xml.readElementText().trimmed();
}
else if (xml.name() == "guid") {
article["id"] = xml.readElementText().trimmed();
}
}
}
if (!article.contains("torrent_url") && article.contains("news_link"))
article["torrent_url"] = article["news_link"];
if (!article.contains("id")) {
// Item does not have a guid, fall back to some other identifier
const QString link = article.value("news_link").toString();
if (!link.isEmpty()) {
article["id"] = link;
}
else {
const QString title = article.value("title").toString();
if (!title.isEmpty()) {
article["id"] = title;
}
else {
qWarning() << "Item has no guid, link or title, ignoring it...";
return;
}
}
}
emit newArticle(article);
}
void Parser::parseRSSChannel(QXmlStreamReader &xml)
{
qDebug() << Q_FUNC_INFO;
Q_ASSERT(xml.isStartElement() && xml.name() == "channel");
while(!xml.atEnd()) {
xml.readNext();
if (xml.isStartElement()) {
if (xml.name() == "title") {
QString title = xml.readElementText();
emit feedTitle(title);
}
else if (xml.name() == "lastBuildDate") {
QString lastBuildDate = xml.readElementText();
if (!lastBuildDate.isEmpty()) {
if (m_lastBuildDate == lastBuildDate) {
qDebug() << "The RSS feed has not changed since last time, aborting parsing.";
return;
}
m_lastBuildDate = lastBuildDate;
}
}
else if (xml.name() == "item") {
parseRssArticle(xml);
}
}
}
}
void Parser::parseAtomArticle(QXmlStreamReader &xml)
{
QVariantHash article;
bool doubleContent = false;
while(!xml.atEnd()) {
xml.readNext();
if(xml.isEndElement() && (xml.name() == "entry"))
break;
if (xml.isStartElement()) {
if (xml.name() == "title") {
article["title"] = xml.readElementText().trimmed();
}
else if (xml.name() == "link") {
QString link = ( xml.attributes().isEmpty() ?
xml.readElementText().trimmed() :
xml.attributes().value("href").toString() );
if (link.startsWith("magnet:", Qt::CaseInsensitive))
article["torrent_url"] = link; // magnet link instead of a news URL
else
// Atom feeds can have relative links, work around this and
// take the stress of figuring article full URI from UI
// Assemble full URI
article["news_link"] = ( m_baseUrl.isEmpty() ? link : m_baseUrl + link );
}
else if ((xml.name() == "summary") || (xml.name() == "content")){
if (doubleContent) { // Duplicate content -> ignore
xml.readNext();
while ((xml.name() != "summary") && (xml.name() != "content"))
xml.readNext();
continue;
}
// Try to also parse broken articles, which don't use html '&' escapes
// Actually works great for non-broken content too
QString feedText = xml.readElementText(QXmlStreamReader::IncludeChildElements);
if (!feedText.isEmpty())
article["description"] = feedText.trimmed();
doubleContent = true;
}
else if (xml.name() == "updated") {
// ATOM uses standard compliant date, don't do fancy stuff
QDateTime articleDate = QDateTime::fromString(xml.readElementText().trimmed(), Qt::ISODate);
article["date"] = (articleDate.isValid() ? articleDate : QDateTime::currentDateTime());
}
else if (xml.name() == "author") {
xml.readNext();
while(xml.name() != "author") {
if(xml.name() == "name")
article["author"] = xml.readElementText().trimmed();
xml.readNext();
}
}
else if (xml.name() == "id") {
article["id"] = xml.readElementText().trimmed();
}
}
}
if (!article.contains("torrent_url") && article.contains("news_link"))
article["torrent_url"] = article["news_link"];
if (!article.contains("id")) {
// Item does not have a guid, fall back to some other identifier
const QString link = article.value("news_link").toString();
if (!link.isEmpty()) {
article["id"] = link;
}
else {
const QString title = article.value("title").toString();
if (!title.isEmpty()) {
article["id"] = title;
}
else {
qWarning() << "Item has no guid, link or title, ignoring it...";
return;
}
}
}
emit newArticle(article);
}
void Parser::parseAtomChannel(QXmlStreamReader &xml)
{
qDebug() << Q_FUNC_INFO;
Q_ASSERT(xml.isStartElement() && xml.name() == "feed");
m_baseUrl = xml.attributes().value("xml:base").toString();
while (!xml.atEnd()) {
xml.readNext();
if (xml.isStartElement()) {
if (xml.name() == "title") {
QString title = xml.readElementText();
emit feedTitle(title);
}
else if (xml.name() == "updated") {
QString lastBuildDate = xml.readElementText();
if (!lastBuildDate.isEmpty()) {
if (m_lastBuildDate == lastBuildDate) {
qDebug() << "The RSS feed has not changed since last time, aborting parsing.";
return;
}
m_lastBuildDate = lastBuildDate;
}
}
else if (xml.name() == "entry") {
parseAtomArticle(xml);
}
}
}
}