/**
* Extracts OpenGraph informations from the given URL.
*
* @param string $url URL to fetch informations from.
* @return array Extracted informations.
*/
protected function _extractInformations($url)
{
$attributes = $this->_Dom->extractAttributes($this->_Http->get($url), ['meta' => ['property' => '#^og:.+#i', 'content']]);
$og = [];
if (empty($attributes['meta'])) {
throw new Exception("Unable to extract OpenGraph data from '{$url}'.");
} else {
foreach ($attributes['meta'] as $meta) {
if (!isset($og[$meta['property']])) {
$og[$meta['property']] = trim($meta['content']);
}
}
}
return $og;
}
/**
* Extracts an oEmbed endpoint from the given URL.
*
* @param string $url URL from which to extract an endpoint.
* @param string $endpoint The extracted endpoint.
* @param string $format The extracted format.
* @return boolean If an endpoint was extracted.
*/
protected function _extractEndpoint($url, &$endpoint, &$format)
{
$attributes = $this->_Dom->extractAttributes($this->_Http->get($url), ['link' => ['rel' => '#alternate#i', 'type', 'href']]);
foreach ($attributes['link'] as $link) {
if (preg_match('#(?<format>json|xml)#i', $link['type'], $matches)) {
$endpoint = $link['href'];
$format = $matches['format'];
return true;
}
}
return false;
}
/**
* Extracts URLs from an HTML source.
*
* @param string $html The HTML source to extract URLs from.
* @return array Extracted URLs.
*/
protected function _extractUrls($html)
{
$options = ['a' => 'href', 'embed' => 'src', 'iframe' => 'src'];
try {
$attributes = $this->_Dom->extractAttributes($html, $options);
} catch (Exception $Exception) {
$this->_Logger->log(Logger::notice, 'Error parsing HTML source', ['exception' => $Exception, 'html' => $html]);
return [];
}
$urls = [];
foreach ($options as $tagName => $attributeName) {
foreach ($attributes[$tagName] as $tag) {
$urls[] = $tag[$attributeName];
}
}
return $urls;
}
