Rss-Bridge/formats/MrssFormat.php
Roliga c8d5c85c76 formats: Add getMimeType() function (#1299)
Allows getting the expected MIME type of the format's output. A
corresponding MIME_TYPE constant is also defined in FormatAbstract for
the format implementations to overwrite.
2019-10-31 19:00:12 +01:00

164 lines
4.7 KiB
PHP

<?php
/**
* MrssFormat - RSS 2.0 + Media RSS
* http://www.rssboard.org/rss-specification
* http://www.rssboard.org/media-rss
*
* Validators:
* https://validator.w3.org/feed/
* http://www.rssboard.org/rss-validator/
*
* Notes about the implementation:
*
* - The item author is not supported as it needs to be an e-mail address to be
* valid.
* - The RSS specification does not explicitly allow to have more than one
* enclosure as every item is meant to provide one "story", thus having
* multiple enclosures per item may lead to unexpected behavior.
* On top of that, it requires to have a length specified, which RSS-Bridge
* can't provide.
* - The Media RSS extension comes in handy, since it allows to have multiple
* enclosures, even though they recommend to have only one enclosure because
* of the one-story-per-item reason. It only requires to specify the URL,
* everything else is optional.
* - Since the Media RSS extension has its own namespace, the output is a valid
* RSS 2.0 feed that works with feed readers that don't support the extension.
*/
class MrssFormat extends FormatAbstract {
const MIME_TYPE = 'application/rss+xml';
const ALLOWED_IMAGE_EXT = array(
'.gif', '.jpg', '.png'
);
public function stringify(){
$urlPrefix = (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on') ? 'https://' : 'http://';
$urlHost = (isset($_SERVER['HTTP_HOST'])) ? $_SERVER['HTTP_HOST'] : '';
$urlPath = (isset($_SERVER['PATH_INFO'])) ? $_SERVER['PATH_INFO'] : '';
$urlRequest = (isset($_SERVER['REQUEST_URI'])) ? $_SERVER['REQUEST_URI'] : '';
$feedUrl = $this->xml_encode($urlPrefix . $urlHost . $urlRequest);
$extraInfos = $this->getExtraInfos();
$title = $this->xml_encode($extraInfos['name']);
$icon = $extraInfos['icon'];
if(!empty($extraInfos['uri'])) {
$uri = $this->xml_encode($extraInfos['uri']);
} else {
$uri = REPOSITORY;
}
$items = '';
foreach($this->getItems() as $item) {
$itemTimestamp = $item->getTimestamp();
$itemTitle = $this->xml_encode($item->getTitle());
$itemUri = $this->xml_encode($item->getURI());
$itemContent = $this->xml_encode($this->sanitizeHtml($item->getContent()));
$entryID = $item->getUid();
$isPermaLink = 'false';
if (empty($entryID) && !empty($itemUri)) { // Fallback to provided URI
$entryID = $itemUri;
$isPermaLink = 'true';
}
if (empty($entryID)) // Fallback to title and content
$entryID = hash('sha1', $itemTitle . $itemContent);
$entryTitle = '';
if (!empty($itemTitle))
$entryTitle = '<title>' . $itemTitle . '</title>';
$entryLink = '';
if (!empty($itemUri))
$entryLink = '<link>' . $itemUri . '</link>';
$entryPublished = '';
if (!empty($itemTimestamp)) {
$entryPublished = '<pubDate>'
. $this->xml_encode(gmdate(DATE_RFC2822, $itemTimestamp))
. '</pubDate>';
}
$entryDescription = '';
if (!empty($itemContent))
$entryDescription = '<description>' . $itemContent . '</description>';
$entryEnclosures = '';
foreach($item->getEnclosures() as $enclosure) {
$entryEnclosures .= '<media:content url="'
. $this->xml_encode($enclosure)
. '" type="' . getMimeType($enclosure) . '"/>'
. PHP_EOL;
}
$entryCategories = '';
foreach($item->getCategories() as $category) {
$entryCategories .= '<category>'
. $category . '</category>'
. PHP_EOL;
}
$items .= <<<EOD
<item>
{$entryTitle}
{$entryLink}
<guid isPermaLink="{$isPermaLink}">{$entryID}</guid>
{$entryPublished}
{$entryDescription}
{$entryEnclosures}
{$entryCategories}
</item>
EOD;
}
$charset = $this->getCharset();
$feedImage = '';
if (!empty($icon) && in_array(substr($icon, -4), self::ALLOWED_IMAGE_EXT)) {
$feedImage .= <<<EOD
<image>
<url>{$icon}</url>
<title>{$title}</title>
<link>{$uri}</link>
</image>
EOD;
}
/* Data are prepared, now let's begin the "MAGIE !!!" */
$toReturn = <<<EOD
<?xml version="1.0" encoding="{$charset}"?>
<rss version="2.0" xmlns:media="http://search.yahoo.com/mrss/" xmlns:atom="http://www.w3.org/2005/Atom">
<channel>
<title>{$title}</title>
<link>{$uri}</link>
<description>{$title}</description>
{$feedImage}
<atom:link rel="alternate" type="text/html" href="{$uri}"/>
<atom:link rel="self" href="{$feedUrl}" type="application/atom+xml"/>
{$items}
</channel>
</rss>
EOD;
// Remove invalid non-UTF8 characters
ini_set('mbstring.substitute_character', 'none');
$toReturn = mb_convert_encoding($toReturn, $this->getCharset(), 'UTF-8');
return $toReturn;
}
public function display(){
$this
->setContentType(self::MIME_TYPE . '; charset=' . $this->getCharset())
->callContentType();
return parent::display();
}
private function xml_encode($text){
return htmlspecialchars($text, ENT_XML1);
}
}