mirror of
https://code.mensbeam.com/MensBeam/Arsse.git
synced 2024-12-22 21:22:40 +00:00
358 lines
No EOL
17 KiB
PHP
358 lines
No EOL
17 KiB
PHP
<?php
|
|
declare(strict_types=1);
|
|
namespace JKingWeb\Arsse;
|
|
use PicoFeed\Reader\Reader;
|
|
use PicoFeed\PicoFeedException;
|
|
use PicoFeed\Reader\Favicon;
|
|
use PicoFeed\Config\Config;
|
|
|
|
class Feed {
|
|
public $data = null;
|
|
public $favicon;
|
|
public $parser;
|
|
public $reader;
|
|
public $resource;
|
|
public $modified = false;
|
|
public $lastModified;
|
|
public $nextFetch;
|
|
public $newItems = [];
|
|
public $changedItems = [];
|
|
|
|
public function __construct(int $feedID = null, string $url, string $lastModified = '', string $etag = '', string $username = '', string $password = '') {
|
|
// fetch the feed
|
|
$this->download($url, $lastModified, $etag, $username, $password);
|
|
// format the HTTP Last-Modified date returned
|
|
$lastMod = $this->resource->getLastModified();
|
|
if(strlen($lastMod)) {
|
|
$this->lastModified = \DateTime::createFromFormat("!D, d M Y H:i:s e", $lastMod);
|
|
}
|
|
$this->modified = $this->resource->isModified();
|
|
//parse the feed, if it has been modified
|
|
if($this->modified) {
|
|
$this->parse();
|
|
// ascertain whether there are any articles not in the database
|
|
$this->matchToDatabase($feedID);
|
|
// if caching header fields are not sent by the server, try to ascertain a last-modified date from the feed contents
|
|
if(!$this->lastModified) $this->lastModified = $this->computeLastModified();
|
|
// we only really care if articles have been modified; if there are no new articles, act as if the feed is unchanged
|
|
if(!sizeof($this->newItems) && !sizeof($this->changedItems)) $this->modified = false;
|
|
}
|
|
// compute the time at which the feed should next be fetched
|
|
$this->nextFetch = $this->computeNextFetch();
|
|
}
|
|
|
|
public function download(string $url, string $lastModified = '', string $etag = '', string $username = '', string $password = ''): bool {
|
|
try {
|
|
$config = new Config;
|
|
$config->setClientUserAgent(Data::$conf->userAgentString);
|
|
$config->setGrabberUserAgent(Data::$conf->userAgentString);
|
|
|
|
$this->reader = new Reader($config);
|
|
$this->resource = $this->reader->download($url, $lastModified, $etag, $username, $password);
|
|
} catch (PicoFeedException $e) {
|
|
throw new Feed\Exception($url, $e);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
public function parse(): bool {
|
|
try {
|
|
$this->parser = $this->reader->getParser(
|
|
$this->resource->getUrl(),
|
|
$this->resource->getContent(),
|
|
$this->resource->getEncoding()
|
|
);
|
|
$feed = $this->parser->execute();
|
|
|
|
// Grab the favicon for the feed; returns an empty string if it cannot find one.
|
|
// Some feeds might use a different domain (eg: feedburner), so the site url is
|
|
// used instead of the feed's url.
|
|
$this->favicon = (new Favicon)->find($feed->siteUrl);
|
|
} catch (PicoFeedException $e) {
|
|
throw new Feed\Exception($this->resource->getUrl(), $e);
|
|
}
|
|
|
|
// PicoFeed does not provide valid ids when there is no id element. Its solution
|
|
// of hashing the url, title, and content together for the id if there is no id
|
|
// element is stupid. Many feeds are frankenstein mixtures of Atom and RSS, but
|
|
// some are pure RSS with guid elements while others use the Dublin Core spec for
|
|
// identification. These feeds shouldn't be duplicated when updated. That should
|
|
// only be reserved for severely broken feeds.
|
|
|
|
foreach ($feed->items as $f) {
|
|
// Hashes used for comparison to check for updates and also to identify when an
|
|
// id doesn't exist.
|
|
$content = $f->content.$f->enclosureUrl.$f->enclosureType;
|
|
// if the item link URL and item title are both equal to the feed link URL, then the item has neither a link URL nor a title
|
|
if($f->url==$feed->siteUrl && $f->title==$feed->siteUrl) {
|
|
$f->urlTitleHash = "";
|
|
} else {
|
|
$f->urlTitleHash = hash('sha256', $f->url.$f->title);
|
|
}
|
|
// if the item link URL is equal to the feed link URL, it has no link URL; if there is additionally no content, these should not be hashed
|
|
if(!strlen($content) && $f->url==$feed->siteUrl) {
|
|
$f->urlContentHash = "";
|
|
} else {
|
|
$f->urlContentHash = hash('sha256', $f->url.$content);
|
|
}
|
|
// if the item's title is the same as its link URL, it has no title; if there is additionally no content, these should not be hashed
|
|
if(!strlen($content) && $f->title==$f->url) {
|
|
$f->titleContentHash = "";
|
|
} else {
|
|
$f->titleContentHash = hash('sha256', $f->title.$content);
|
|
}
|
|
|
|
// If there is an id element then continue. The id is used already.
|
|
$id = (string)$f->xml->id;
|
|
if ($id !== '') {
|
|
continue;
|
|
}
|
|
|
|
// If there is a guid element use it as the id.
|
|
$id = (string)$f->xml->guid;
|
|
if ($id !== '') {
|
|
$f->id = hash('sha256', $id);
|
|
continue;
|
|
}
|
|
|
|
// If there is a Dublin Core identifier use it.
|
|
$id = (string)$f->xml->children('http://purl.org/dc/elements/1.1/')->identifier;
|
|
if ($id !== '') {
|
|
$f->id = hash('sha256', $id);
|
|
continue;
|
|
}
|
|
|
|
// If there aren't any of those there is no id.
|
|
$f->id = '';
|
|
}
|
|
$this->data = $feed;
|
|
return true;
|
|
}
|
|
|
|
protected function deduplicateItems(array $items): array {
|
|
/* Rationale:
|
|
Some newsfeeds (notably Planet) include multiple versions of an
|
|
item if it is updated. As we only care about the latest, we
|
|
try to remove any "old" versions of an item that might also be
|
|
present within the feed.
|
|
*/
|
|
$out = [];
|
|
foreach($items as $item) {
|
|
foreach($out as $index => $check) {
|
|
// if the two items both have IDs and they differ, they do not match, regardless of hashes
|
|
if($item->id && $check->id && $item->id != $check->id) continue;
|
|
// if the two items have the same ID or any one hash matches, they are two versions of the same item
|
|
if(
|
|
($item->id && $check->id && $item->id == $check->id) ||
|
|
($item->urlTitleHash && $item->urlTitleHash == $check->urlTitleHash) ||
|
|
($item->urlContentHash && $item->urlContentHash == $check->urlContentHash) ||
|
|
($item->titleContentHash && $item->titleContentHash == $check->titleContentHash)
|
|
) {
|
|
if(// because newsfeeds are usually order newest-first, the later item should only be used if...
|
|
// the later item has an update date and the existing item does not
|
|
($item->updatedDate && !$check->updatedDate) ||
|
|
// the later item has an update date newer than the existing item's
|
|
($item->updatedDate && $check->updatedDate && $item->updatedDate->getTimestamp() > $check->updatedDate->getTimestamp()) ||
|
|
// neither item has update dates, both have publish dates, and the later item has a newer publish date
|
|
(!$item->updatedDate && !$check->updatedDate && $item->publishedDate && $check->publishedDate && $item->publishedDate->getTimestamp() > $check->publishedDate->getTimestamp())
|
|
) {
|
|
// if the later item should be used, replace the existing one
|
|
$out[$index] = $item;
|
|
continue 2;
|
|
} else {
|
|
// otherwise skip the item
|
|
continue 2;
|
|
}
|
|
}
|
|
}
|
|
// if there was no match, add the item
|
|
$out[] = $item;
|
|
}
|
|
return $out;
|
|
}
|
|
|
|
public function matchToDatabase(int $feedID = null): bool {
|
|
// first perform deduplication on items
|
|
$items = $this->deduplicateItems($this->data->items);
|
|
// if we haven't been given a database feed ID to check against, all items are new
|
|
if(is_null($feedID)) {
|
|
$this->newItems = $items;
|
|
return true;
|
|
}
|
|
// get as many of the latest articles in the database as there are in the feed
|
|
$articles = Data::$db->articleMatchLatest($feedID, sizeof($items));
|
|
// arrays holding new, edited, and tentatively new items; items may be tentatively new because we perform two passes
|
|
$new = $tentative = $edited = [];
|
|
// iterate through the articles and for each determine whether it is existing, edited, or entirely new
|
|
foreach($items as $index => $i) {
|
|
$found = false;
|
|
foreach($articles as $a) {
|
|
// if the item has an ID and it doesn't match the article ID, the two don't match, regardless of hashes
|
|
if($i->id && $i->id !== $a['guid']) continue;
|
|
if(
|
|
// the item matches if the GUID matches...
|
|
($i->id && $i->id === $a['guid']) ||
|
|
// ... or if any one of the hashes match
|
|
($i->urlTitleHash && $i->urlTitleHash === $a['url_title_hash']) ||
|
|
($i->urlContentHash && $i->urlContentHash === $a['url_content_hash']) ||
|
|
($i->titleContentHash && $i->titleContentHash === $a['title_content_hash'])
|
|
) {
|
|
if($i->updatedDate && $i->updatedDate->getTimestamp() !== $match['edited_date']) {
|
|
// if the item has an edit timestamp and it doesn't match that of the article in the database, the the article has been edited
|
|
// we store the item index and database record ID as a key/value pair
|
|
$found = true;
|
|
$edited[$index] = $a['id'];
|
|
break;
|
|
} else if($i->urlTitleHash !== $a['url_title_hash'] || $i->urlContentHash !== $a['url_content_hash'] || $i->titleContentHash !== $a['title_content_hash']) {
|
|
// if any of the hashes do not match, then the article has been edited
|
|
$found = true;
|
|
$edited[$index] = $a['id'];
|
|
break;
|
|
} else {
|
|
// otherwise the item is unchanged and we can ignore it
|
|
$found = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if(!$found) $tentative[] = $index;
|
|
}
|
|
if(sizeof($tentative) && sizeof($items)==sizeof($articles)) {
|
|
// if we need to, perform a second pass on the database looking specifically for IDs and hashes of the new items
|
|
$ids = $hashesUT = $hashesUC = $hashesTC = [];
|
|
foreach($tentative as $index) {
|
|
$i = $items[$index];
|
|
if($i->id) $ids[] = $i->id;
|
|
if($i->urlTitleHash) $hashesUT[] = $i->urlTitleHash;
|
|
if($i->urlContentHash) $hashesUC[] = $i->urlContentHash;
|
|
if($i->titleContentHash) $hashesTC[] = $i->titleContentHash;
|
|
}
|
|
$articles = Data::$db->articleMatchIds($feedID, $ids, $hashesUT, $hashesUC, $hashesTC);
|
|
foreach($tentative as $index) {
|
|
$i = $items[$index];
|
|
$found = false;
|
|
foreach($articles as $a) {
|
|
// if the item has an ID and it doesn't match the article ID, the two don't match, regardless of hashes
|
|
if($i->id && $i->id !== $a['guid']) continue;
|
|
if(
|
|
// the item matches if the GUID matches...
|
|
($i->id && $i->id === $a['guid']) ||
|
|
// ... or if any one of the hashes match
|
|
($i->urlTitleHash && $i->urlTitleHash === $a['url_title_hash']) ||
|
|
($i->urlContentHash && $i->urlContentHash === $a['url_content_hash']) ||
|
|
($i->titleContentHash && $i->titleContentHash === $a['title_content_hash'])
|
|
) {
|
|
if($i->updatedDate && $i->updatedDate->getTimestamp() !== $match['edited_date']) {
|
|
// if the item has an edit timestamp and it doesn't match that of the article in the database, the the article has been edited
|
|
// we store the item index and database record ID as a key/value pair
|
|
$found = true;
|
|
$edited[$index] = $a['id'];
|
|
break;
|
|
} else if($i->urlTitleHash !== $a['url_title_hash'] || $i->urlContentHash !== $a['url_content_hash'] || $i->titleContentHash !== $a['title_content_hash']) {
|
|
// if any of the hashes do not match, then the article has been edited
|
|
$found = true;
|
|
$edited[$index] = $a['id'];
|
|
break;
|
|
} else {
|
|
// otherwise the item is unchanged and we can ignore it
|
|
$found = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if(!$found) $new[] = $index;
|
|
}
|
|
} else {
|
|
// if there are no tentatively new articles and/or the number of stored articles is less than the size of the feed, don't do a second pass; assume any tentatively new items are in fact new
|
|
$new = $tentative;
|
|
}
|
|
// TODO: fetch full content when appropriate
|
|
foreach($new as $index) {
|
|
$this->newItems[] = $items[$index];
|
|
}
|
|
foreach($edited as $index => $id) {
|
|
$this->changedItems[$id] = $items[$index];
|
|
}
|
|
return true;
|
|
}
|
|
|
|
public function computeNextFetch(): \DateTime {
|
|
$now = new \DateTime();
|
|
if(!$this->modified) {
|
|
$diff = $now->getTimestamp() - $this->lastModified->getTimestamp();
|
|
$offset = $this->normalizeDateDiff($diff);
|
|
$now->modify("+".$offset);
|
|
} else {
|
|
$offsets = [];
|
|
$dates = $this->gatherDates();
|
|
if(sizeof($dates) > 3) {
|
|
for($a = 0; $a < 3; $a++) {
|
|
$diff = $dates[$a+1] - $dates[$a];
|
|
$offsets[] = $this->normalizeDateDiff($diff);
|
|
}
|
|
if($offsets[0]==$offsets[1] || $offsets[0]==$offsets[2]) {
|
|
$now->modify("+".$offsets[0]);
|
|
} else if($offsets[1]==$offsets[2]) {
|
|
$now->modify("+".$offsets[1]);
|
|
} else {
|
|
$now->modify("+ 1 hour");
|
|
}
|
|
} else {
|
|
$now->modify("+ 1 hour");
|
|
}
|
|
}
|
|
return $now;
|
|
}
|
|
|
|
public static function nextFetchOnError($errCount): \DateTime {
|
|
if($errCount < 3) {
|
|
$offset = "5 minutes";
|
|
} else if($errCount < 15) {
|
|
$offset = "3 hours";
|
|
} else {
|
|
$offset = "1 day";
|
|
}
|
|
return new \DateTime("now + ".$offset);
|
|
}
|
|
|
|
protected function normalizeDateDiff(int $diff): string {
|
|
if($diff < (30 * 60)) { // less than 30 minutes
|
|
$offset = "15 minutes";
|
|
} else if($diff < (60 * 60)) { // less than an hour
|
|
$offset = "30 minutes";
|
|
} else if($diff < (3 * 60 * 60)) { // less than three hours
|
|
$offset = "1 hour";
|
|
} else if($diff >= (36 * 60 * 60)) { // more than 36 hours
|
|
$offset = "1 day";
|
|
} else {
|
|
$offset = "3 hours";
|
|
}
|
|
return $offset;
|
|
}
|
|
|
|
public function computeLastModified() {
|
|
if(!$this->modified) {
|
|
return $this->lastModified;
|
|
} else {
|
|
$dates = $this->gatherDates();
|
|
}
|
|
if(sizeof($dates)) {
|
|
$now = new \DateTime();
|
|
$now->setTimestamp($dates[0]);
|
|
return $now;
|
|
} else {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
protected function gatherDates(): array {
|
|
$dates = [];
|
|
foreach($this->data->items as $item) {
|
|
if($item->updatedDate) $dates[] = $item->updatedDate->getTimestamp();
|
|
if($item->publishedDate) $dates[] = $item->publishedDate->getTimestamp();
|
|
}
|
|
$dates = array_unique($dates, \SORT_NUMERIC);
|
|
rsort($dates);
|
|
return $dates;
|
|
}
|
|
} |