diff options
Diffstat (limited to 'classes/FeedParser.php')
| -rw-r--r-- | classes/FeedParser.php | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/classes/FeedParser.php b/classes/FeedParser.php new file mode 100644 index 000000000..4b9c63f56 --- /dev/null +++ b/classes/FeedParser.php @@ -0,0 +1,245 @@ +<?php +class FeedParser { + + /** @var DOMDocument */ + private $doc; + + /** @var string|null */ + private $error = null; + + /** @var array<string> */ + private $libxml_errors = []; + + /** @var array<FeedItem> */ + private $items = []; + + /** @var string|null */ + private $link; + + /** @var string|null */ + private $title; + + /** @var FeedParser::FEED_*|null */ + private $type; + + /** @var DOMXPath|null */ + private $xpath; + + const FEED_RDF = 0; + const FEED_RSS = 1; + const FEED_ATOM = 2; + + function __construct(string $data) { + libxml_use_internal_errors(true); + libxml_clear_errors(); + $this->doc = new DOMDocument(); + $this->doc->loadXML($data); + + mb_substitute_character("none"); + + $error = libxml_get_last_error(); + + if ($error) { + foreach (libxml_get_errors() as $error) { + if ($error->level == LIBXML_ERR_FATAL) { + // currently only the first error is reported + $this->error ??= Errors::format_libxml_error($error); + $this->libxml_errors[] = Errors::format_libxml_error($error); + } + } + } + libxml_clear_errors(); + } + + function init() : void { + $root = $this->doc->firstChild; + $xpath = new DOMXPath($this->doc); + $xpath->registerNamespace('atom', 'http://www.w3.org/2005/Atom'); + $xpath->registerNamespace('atom03', 'http://purl.org/atom/ns#'); + $xpath->registerNamespace('media', 'http://search.yahoo.com/mrss/'); + $xpath->registerNamespace('rdf', 'http://www.w3.org/1999/02/22-rdf-syntax-ns#'); + $xpath->registerNamespace('slash', 'http://purl.org/rss/1.0/modules/slash/'); + $xpath->registerNamespace('dc', 'http://purl.org/dc/elements/1.1/'); + $xpath->registerNamespace('content', 'http://purl.org/rss/1.0/modules/content/'); + $xpath->registerNamespace('thread', 'http://purl.org/syndication/thread/1.0'); + + $this->xpath = $xpath; + + $root_list = $xpath->query("(//atom03:feed|//atom:feed|//channel|//rdf:rdf|//rdf:RDF)"); + + if (!empty($root_list) && $root_list->length > 0) { + + /** @var DOMElement|null $root */ + $root = $root_list->item(0); + + if ($root) { + switch (mb_strtolower($root->tagName)) { + case "rdf:rdf": + $this->type = $this::FEED_RDF; + break; + case "channel": + $this->type = $this::FEED_RSS; + break; + case "feed": + case "atom:feed": + $this->type = $this::FEED_ATOM; + break; + default: + $this->error ??= "Unknown/unsupported feed type"; + return; + } + } + + switch ($this->type) { + case $this::FEED_ATOM: + + $title = $xpath->query("//atom:feed/atom:title")->item(0); + + if (!$title) + $title = $xpath->query("//atom03:feed/atom03:title")->item(0); + + + if ($title) { + $this->title = $title->nodeValue; + } + + $link = $xpath->query("//atom:feed/atom:link[not(@rel)]")->item(0); + + if (!$link) + $link = $xpath->query("//atom:feed/atom:link[@rel='alternate']")->item(0); + + if (!$link) + $link = $xpath->query("//atom03:feed/atom03:link[not(@rel)]")->item(0); + + if (!$link) + $link = $xpath->query("//atom03:feed/atom03:link[@rel='alternate']")->item(0); + + /** @var DOMElement|null $link */ + if ($link && $link->hasAttributes()) { + $this->link = $link->getAttribute("href"); + } + + $articles = $xpath->query("//atom:entry"); + + if (empty($articles) || $articles->length == 0) + $articles = $xpath->query("//atom03:entry"); + + foreach ($articles as $article) { + array_push($this->items, new FeedItem_Atom($article, $this->doc, $this->xpath)); + } + + break; + case $this::FEED_RSS: + $title = $xpath->query("//channel/title")->item(0); + + if ($title) { + $this->title = $title->nodeValue; + } + + /** @var DOMElement|null $link */ + $link = $xpath->query("//channel/link")->item(0); + + if ($link) { + if ($link->getAttribute("href")) + $this->link = $link->getAttribute("href"); + else if ($link->nodeValue) + $this->link = $link->nodeValue; + } + + $articles = $xpath->query("//channel/item"); + + foreach ($articles as $article) { + array_push($this->items, new FeedItem_RSS($article, $this->doc, $this->xpath)); + } + + break; + case $this::FEED_RDF: + $xpath->registerNamespace('rssfake', 'http://purl.org/rss/1.0/'); + + $title = $xpath->query("//rssfake:channel/rssfake:title")->item(0); + + if ($title) { + $this->title = $title->nodeValue; + } + + $link = $xpath->query("//rssfake:channel/rssfake:link")->item(0); + + if ($link) { + $this->link = $link->nodeValue; + } + + $articles = $xpath->query("//rssfake:item"); + + foreach ($articles as $article) { + array_push($this->items, new FeedItem_RSS($article, $this->doc, $this->xpath)); + } + + break; + + } + + if ($this->title) $this->title = trim($this->title); + if ($this->link) $this->link = trim($this->link); + + } else { + $this->error ??= "Unknown/unsupported feed type"; + return; + } + } + + /** @deprecated use Errors::format_libxml_error() instead */ + function format_error(LibXMLError $error) : string { + return Errors::format_libxml_error($error); + } + + // libxml may have invalid unicode data in error messages + function error() : string { + return UConverter::transcode($this->error ?? '', 'UTF-8', 'UTF-8'); + } + + /** @return array<string> - WARNING: may return invalid unicode data */ + function errors() : array { + return $this->libxml_errors; + } + + function get_link() : string { + return clean($this->link ?? ''); + } + + function get_title() : string { + return clean($this->title ?? ''); + } + + /** @return array<FeedItem> */ + function get_items() : array { + return $this->items; + } + + /** @return array<string> */ + function get_links(string $rel) : array { + $rv = array(); + + switch ($this->type) { + case $this::FEED_ATOM: + $links = $this->xpath->query("//atom:feed/atom:link"); + + foreach ($links as $link) { + if (!$rel || $link->hasAttribute('rel') && $link->getAttribute('rel') == $rel) { + array_push($rv, clean(trim($link->getAttribute('href')))); + } + } + break; + case $this::FEED_RSS: + $links = $this->xpath->query("//atom:link"); + + foreach ($links as $link) { + if (!$rel || $link->hasAttribute('rel') && $link->getAttribute('rel') == $rel) { + array_push($rv, clean(trim($link->getAttribute('href')))); + } + } + break; + } + + return $rv; + } +} |