/**
* Checks a given URL (+shortened) against the cache to verify if they were
* previously posted on the channel.
*
* @param string $url The URL to check against
* @param string $shortenedUrl The shortened URL to check against
*
* @return bool
*/
protected function checkUrlCache($url, $shortenedUrl)
{
$cache = array();
$source = $this->getEvent()->getSource();
/**
* Transform URL (+shortened) into HEX CRC32 checksum to prevent
* problems and minimize cache size for less bloat
*/
$url = $this->getUrlChecksum($url);
$shortenedUrl = $this->getUrlChecksum($shortenedUrl);
$cache['url'] = $this->cache->fetch('urlCache');
$cache['shortened'] = $this->cache->fetch('shortCache');
$expire = $this->getConfig('url.expire', 1800);
$this->debug("Cache expire: {$expire}");
/**
* If cache expiration is enabled, check if given URL has expired in
* cache; if expire is disabled, check if the URL is listed
*/
if ($expire > 0 && isset($cache['url'][$source], $cache['shortened'][$source])) {
unset($cache, $url, $shortenedUrl, $expire);
return true;
}
unset($cache, $url, $shortenedUrl, $expire);
return false;
}
/**
* Updates the cache and adds the given URL (+shortened) to the cache. It
* also handles cleaning the cache of old entries as well.
*
* @param string $url The URL to add to the cache
* @param string $shortenedUrl The shortened to add to the cache
*
* @return bool
*/
protected function updateUrlCache($url, $shortenedUrl)
{
$cache = array();
$source = $this->getEvent()->getSource();
$cache['urlCache'] = $this->cache->fetch('urlCache');
$cache['shortCache'] = $this->cache->fetch('shortCache');
/**
* Transform URL (+shortened) into HEX CRC32 checksum to prevent
* problems and minimize cache size for less bloat
*/
$url = $this->getUrlChecksum($url);
$shortenedUrl = $this->getUrlChecksum($shortenedUrl);
$time = time();
/**
* Handle URL cache and remove old entries that surpass the limit if
* enabled
*/
$cache['urlCache'][$source][$url] = $time;
if ($this->limit > 0 && count($cache['urlCache'][$source]) > $this->limit) {
asort($cache['urlCache'][$source], SORT_NUMERIC);
array_shift($cache['urlCache'][$source]);
}
/**
* Handle shortened cache and remove old entries that surpass the
* limit if enabled
*/
$cache['shortCache'][$source][$shortenedUrl] = $time;
if ($this->limit > 0 && count($cache['shortCache'][$source]) > $this->limit) {
asort($cache['shortCache'][$source], SORT_NUMERIC);
array_shift($cache['shortCache'][$source]);
}
$this->cache->store('urlCache', $cache['urlCache'], $this->expire);
$this->cache->store('shortCache', $cache['shortCache'], $this->expire);
unset($url, $shortenedUrl, $time);
}