mirror of
https://github.com/RSS-Bridge/rss-bridge.git
synced 2024-11-26 19:36:52 +03:00
411 lines
12 KiB
PHP
411 lines
12 KiB
PHP
<?php
|
|
/**
|
|
* This file is part of RSS-Bridge, a PHP project capable of generating RSS and
|
|
* Atom feeds for websites that don't have one.
|
|
*
|
|
* For the full license information, please view the UNLICENSE file distributed
|
|
* with this source code.
|
|
*
|
|
* @package Core
|
|
* @license http://unlicense.org/ UNLICENSE
|
|
* @link https://github.com/rss-bridge/rss-bridge
|
|
*/
|
|
|
|
/**
|
|
* An abstract class for bridges that need to transform existing RSS or Atom
|
|
* feeds.
|
|
*
|
|
* This class extends {@see BridgeAbstract} with functions to extract contents
|
|
* from existing RSS or Atom feeds. Bridges that need to transform existing feeds
|
|
* should inherit from this class instead of {@see BridgeAbstract}.
|
|
*
|
|
* Bridges that extend this class don't need to concern themselves with getting
|
|
* contents from existing feeds, but can focus on adding additional contents
|
|
* (i.e. by downloading additional data), filtering or just transforming a feed
|
|
* into another format.
|
|
*
|
|
* @link http://www.rssboard.org/rss-0-9-1 RSS 0.91 Specification
|
|
* @link http://web.resource.org/rss/1.0/spec RDF Site Summary (RSS) 1.0
|
|
* @link http://www.rssboard.org/rss-specification RSS 2.0 Specification
|
|
* @link https://tools.ietf.org/html/rfc4287 The Atom Syndication Format
|
|
*
|
|
* @todo The parsing functions should all be private. This class is complicated
|
|
* enough without having to consider children overriding functions.
|
|
*/
|
|
abstract class FeedExpander extends BridgeAbstract {
|
|
|
|
/**
|
|
* Holds the title of the current feed
|
|
*
|
|
* @var string
|
|
* @todo Rename this parameter to $title for clarity
|
|
*/
|
|
private $name;
|
|
|
|
/**
|
|
* Holds the URI of the feed
|
|
*
|
|
* @var string
|
|
*/
|
|
private $uri;
|
|
|
|
/**
|
|
* Holds the feed type during internal operations.
|
|
*
|
|
* @var string
|
|
* @todo Define possible values as constant instead of static strings
|
|
*/
|
|
private $feedType;
|
|
|
|
/**
|
|
* Collects data from an existing feed.
|
|
*
|
|
* Children should call this function in {@see BridgeInterface::collectData()}
|
|
* to extract a feed.
|
|
*
|
|
* @param string $url URL to the feed.
|
|
* @param int $maxItems Maximum number of items to collect from the feed
|
|
* (`-1`: no limit).
|
|
* @return self
|
|
*/
|
|
public function collectExpandableDatas($url, $maxItems = -1){
|
|
if(empty($url)) {
|
|
returnServerError('There is no $url for this RSS expander');
|
|
}
|
|
|
|
Debug::log('Loading from ' . $url);
|
|
|
|
/* Notice we do not use cache here on purpose:
|
|
* we want a fresh view of the RSS stream each time
|
|
*/
|
|
$content = getContents($url)
|
|
or returnServerError('Could not request ' . $url);
|
|
$rssContent = simplexml_load_string(trim($content));
|
|
|
|
Debug::log('Detecting feed format/version');
|
|
switch(true) {
|
|
case isset($rssContent->item[0]):
|
|
Debug::log('Detected RSS 1.0 format');
|
|
$this->feedType = 'RSS_1_0';
|
|
break;
|
|
case isset($rssContent->channel[0]):
|
|
Debug::log('Detected RSS 0.9x or 2.0 format');
|
|
$this->feedType = 'RSS_2_0';
|
|
break;
|
|
case isset($rssContent->entry[0]):
|
|
Debug::log('Detected ATOM format');
|
|
$this->feedType = 'ATOM_1_0';
|
|
break;
|
|
default:
|
|
Debug::log('Unknown feed format/version');
|
|
returnServerError('The feed format is unknown!');
|
|
break;
|
|
}
|
|
|
|
Debug::log('Calling function "collect_' . $this->feedType . '_data"');
|
|
$this->{'collect_' . $this->feedType . '_data'}($rssContent, $maxItems);
|
|
|
|
return $this;
|
|
}
|
|
|
|
/**
|
|
* Collect data from a RSS 1.0 compatible feed
|
|
*
|
|
* @link http://web.resource.org/rss/1.0/spec RDF Site Summary (RSS) 1.0
|
|
*
|
|
* @param string $rssContent The RSS content
|
|
* @param int $maxItems Maximum number of items to collect from the feed
|
|
* (`-1`: no limit).
|
|
* @return void
|
|
*
|
|
* @todo Instead of passing $maxItems to all functions, just add all items
|
|
* and remove excessive items later.
|
|
*/
|
|
protected function collect_RSS_1_0_data($rssContent, $maxItems){
|
|
$this->load_RSS_2_0_feed_data($rssContent->channel[0]);
|
|
foreach($rssContent->item as $item) {
|
|
Debug::log('parsing item ' . var_export($item, true));
|
|
$tmp_item = $this->parseItem($item);
|
|
if (!empty($tmp_item)) {
|
|
$this->items[] = $tmp_item;
|
|
}
|
|
if($maxItems !== -1 && count($this->items) >= $maxItems) break;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Collect data from a RSS 2.0 compatible feed
|
|
*
|
|
* @link http://www.rssboard.org/rss-specification RSS 2.0 Specification
|
|
*
|
|
* @param object $rssContent The RSS content
|
|
* @param int $maxItems Maximum number of items to collect from the feed
|
|
* (`-1`: no limit).
|
|
* @return void
|
|
*
|
|
* @todo Instead of passing $maxItems to all functions, just add all items
|
|
* and remove excessive items later.
|
|
*/
|
|
protected function collect_RSS_2_0_data($rssContent, $maxItems){
|
|
$rssContent = $rssContent->channel[0];
|
|
Debug::log('RSS content is ===========\n'
|
|
. var_export($rssContent, true)
|
|
. '===========');
|
|
|
|
$this->load_RSS_2_0_feed_data($rssContent);
|
|
foreach($rssContent->item as $item) {
|
|
Debug::log('parsing item ' . var_export($item, true));
|
|
$tmp_item = $this->parseItem($item);
|
|
if (!empty($tmp_item)) {
|
|
$this->items[] = $tmp_item;
|
|
}
|
|
if($maxItems !== -1 && count($this->items) >= $maxItems) break;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Collect data from a Atom 1.0 compatible feed
|
|
*
|
|
* @link https://tools.ietf.org/html/rfc4287 The Atom Syndication Format
|
|
*
|
|
* @param object $content The Atom content
|
|
* @param int $maxItems Maximum number of items to collect from the feed
|
|
* (`-1`: no limit).
|
|
* @return void
|
|
*
|
|
* @todo Instead of passing $maxItems to all functions, just add all items
|
|
* and remove excessive items later.
|
|
*/
|
|
protected function collect_ATOM_1_0_data($content, $maxItems){
|
|
$this->load_ATOM_feed_data($content);
|
|
foreach($content->entry as $item) {
|
|
Debug::log('parsing item ' . var_export($item, true));
|
|
$tmp_item = $this->parseItem($item);
|
|
if (!empty($tmp_item)) {
|
|
$this->items[] = $tmp_item;
|
|
}
|
|
if($maxItems !== -1 && count($this->items) >= $maxItems) break;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Convert RSS 2.0 time to timestamp
|
|
*
|
|
* @param object $item A feed item
|
|
* @return int The timestamp
|
|
*/
|
|
protected function RSS_2_0_time_to_timestamp($item){
|
|
return DateTime::createFromFormat('D, d M Y H:i:s e', $item->pubDate)->getTimestamp();
|
|
}
|
|
|
|
/**
|
|
* Load RSS 2.0 feed data into RSS-Bridge
|
|
*
|
|
* @param object $rssContent The RSS content
|
|
* @return void
|
|
*
|
|
* @todo set title, link, description, language, and so on
|
|
*/
|
|
protected function load_RSS_2_0_feed_data($rssContent){
|
|
$this->name = trim((string)$rssContent->title);
|
|
$this->uri = trim((string)$rssContent->link);
|
|
}
|
|
|
|
/**
|
|
* Load Atom feed data into RSS-Bridge
|
|
*
|
|
* @param object $content The Atom content
|
|
* @return void
|
|
*/
|
|
protected function load_ATOM_feed_data($content){
|
|
$this->name = (string)$content->title;
|
|
|
|
// Find best link (only one, or first of 'alternate')
|
|
if(!isset($content->link)) {
|
|
$this->uri = '';
|
|
} elseif (count($content->link) === 1) {
|
|
$this->uri = (string)$content->link[0]['href'];
|
|
} else {
|
|
$this->uri = '';
|
|
foreach($content->link as $link) {
|
|
if(strtolower($link['rel']) === 'alternate') {
|
|
$this->uri = (string)$link['href'];
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Parse the contents of a single Atom feed item into a RSS-Bridge item for
|
|
* further transformation.
|
|
*
|
|
* @param object $feedItem A single feed item
|
|
* @return object The RSS-Bridge item
|
|
*
|
|
* @todo To reduce confusion, the RSS-Bridge item should maybe have a class
|
|
* of its own?
|
|
*/
|
|
protected function parseATOMItem($feedItem){
|
|
// Some ATOM entries also contain RSS 2.0 fields
|
|
$item = $this->parseRSS_2_0_Item($feedItem);
|
|
|
|
if(isset($feedItem->id)) $item['uri'] = (string)$feedItem->id;
|
|
if(isset($feedItem->title)) $item['title'] = (string)$feedItem->title;
|
|
if(isset($feedItem->updated)) $item['timestamp'] = strtotime((string)$feedItem->updated);
|
|
if(isset($feedItem->author)) $item['author'] = (string)$feedItem->author->name;
|
|
if(isset($feedItem->content)) $item['content'] = (string)$feedItem->content;
|
|
|
|
//When "link" field is present, URL is more reliable than "id" field
|
|
if (count($feedItem->link) === 1) {
|
|
$this->uri = (string)$feedItem->link[0]['href'];
|
|
} else {
|
|
foreach($feedItem->link as $link) {
|
|
if(strtolower($link['rel']) === 'alternate') {
|
|
$item['uri'] = (string)$link['href'];
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
return $item;
|
|
}
|
|
|
|
/**
|
|
* Parse the contents of a single RSS 0.91 feed item into a RSS-Bridge item
|
|
* for further transformation.
|
|
*
|
|
* @param object $feedItem A single feed item
|
|
* @return object The RSS-Bridge item
|
|
*
|
|
* @todo To reduce confusion, the RSS-Bridge item should maybe have a class
|
|
* of its own?
|
|
*/
|
|
protected function parseRSS_0_9_1_Item($feedItem){
|
|
$item = array();
|
|
if(isset($feedItem->link)) $item['uri'] = (string)$feedItem->link;
|
|
if(isset($feedItem->title)) $item['title'] = (string)$feedItem->title;
|
|
// rss 0.91 doesn't support timestamps
|
|
// rss 0.91 doesn't support authors
|
|
// rss 0.91 doesn't support enclosures
|
|
if(isset($feedItem->description)) $item['content'] = (string)$feedItem->description;
|
|
return $item;
|
|
}
|
|
|
|
/**
|
|
* Parse the contents of a single RSS 1.0 feed item into a RSS-Bridge item
|
|
* for further transformation.
|
|
*
|
|
* @param object $feedItem A single feed item
|
|
* @return object The RSS-Bridge item
|
|
*
|
|
* @todo To reduce confusion, the RSS-Bridge item should maybe have a class
|
|
* of its own?
|
|
*/
|
|
protected function parseRSS_1_0_Item($feedItem){
|
|
// 1.0 adds optional elements around the 0.91 standard
|
|
$item = $this->parseRSS_0_9_1_Item($feedItem);
|
|
|
|
$namespaces = $feedItem->getNamespaces(true);
|
|
if(isset($namespaces['dc'])) {
|
|
$dc = $feedItem->children($namespaces['dc']);
|
|
if(isset($dc->date)) $item['timestamp'] = strtotime((string)$dc->date);
|
|
if(isset($dc->creator)) $item['author'] = (string)$dc->creator;
|
|
}
|
|
|
|
return $item;
|
|
}
|
|
|
|
/**
|
|
* Parse the contents of a single RSS 2.0 feed item into a RSS-Bridge item
|
|
* for further transformation.
|
|
*
|
|
* @param object $feedItem A single feed item
|
|
* @return object The RSS-Bridge item
|
|
*
|
|
* @todo To reduce confusion, the RSS-Bridge item should maybe have a class
|
|
* of its own?
|
|
*/
|
|
protected function parseRSS_2_0_Item($feedItem){
|
|
// Primary data is compatible to 0.91 with some additional data
|
|
$item = $this->parseRSS_0_9_1_Item($feedItem);
|
|
|
|
$namespaces = $feedItem->getNamespaces(true);
|
|
if(isset($namespaces['dc'])) $dc = $feedItem->children($namespaces['dc']);
|
|
if(isset($namespaces['media'])) $media = $feedItem->children($namespaces['media']);
|
|
|
|
if(isset($feedItem->guid)) {
|
|
foreach($feedItem->guid->attributes() as $attribute => $value) {
|
|
if($attribute === 'isPermaLink'
|
|
&& ($value === 'true' || (
|
|
filter_var($feedItem->guid, FILTER_VALIDATE_URL)
|
|
&& !filter_var($item['uri'], FILTER_VALIDATE_URL)
|
|
)
|
|
)
|
|
) {
|
|
$item['uri'] = (string)$feedItem->guid;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if(isset($feedItem->pubDate)) {
|
|
$item['timestamp'] = strtotime((string)$feedItem->pubDate);
|
|
} elseif(isset($dc->date)) {
|
|
$item['timestamp'] = strtotime((string)$dc->date);
|
|
}
|
|
|
|
if(isset($feedItem->author)) {
|
|
$item['author'] = (string)$feedItem->author;
|
|
} elseif (isset($feedItem->creator)) {
|
|
$item['author'] = (string)$feedItem->creator;
|
|
} elseif(isset($dc->creator)) {
|
|
$item['author'] = (string)$dc->creator;
|
|
} elseif(isset($media->credit)) {
|
|
$item['author'] = (string)$media->credit;
|
|
}
|
|
|
|
if(isset($feedItem->enclosure) && !empty($feedItem->enclosure['url'])) {
|
|
$item['enclosures'] = array((string)$feedItem->enclosure['url']);
|
|
}
|
|
|
|
return $item;
|
|
}
|
|
|
|
/**
|
|
* Parse the contents of a single feed item, depending on the current feed
|
|
* type, into a RSS-Bridge item.
|
|
*
|
|
* @param object $item The current feed item
|
|
* @return object A RSS-Bridge item, with (hopefully) the whole content
|
|
*/
|
|
protected function parseItem($item){
|
|
switch($this->feedType) {
|
|
case 'RSS_1_0':
|
|
return $this->parseRSS_1_0_Item($item);
|
|
break;
|
|
case 'RSS_2_0':
|
|
return $this->parseRSS_2_0_Item($item);
|
|
break;
|
|
case 'ATOM_1_0':
|
|
return $this->parseATOMItem($item);
|
|
break;
|
|
default: returnClientError('Unknown version ' . $this->getInput('version') . '!');
|
|
}
|
|
}
|
|
|
|
/** {@inheritdoc} */
|
|
public function getURI(){
|
|
return !empty($this->uri) ? $this->uri : parent::getURI();
|
|
}
|
|
|
|
/** {@inheritdoc} */
|
|
public function getName(){
|
|
return !empty($this->name) ? $this->name : parent::getName();
|
|
}
|
|
|
|
/** {@inheritdoc} */
|
|
public function getIcon(){
|
|
return !empty($this->icon) ? $this->icon : parent::getIcon();
|
|
}
|
|
}
|