/**
* Evaluates the result of the given callback
*
* @param string $key Unique key for this
* @param callable $callback Callback for evaluating the content
* @return mixed Result of $callback()
*/
public function getContent($key, $callback)
{
if ($this->nestedContentFilter) {
return $this->nestedContentFilter->getContent($key, $callback);
} else {
return call_user_func($callback);
}
}
public function getContent($key, $callback)
{
$cache = $this->getCache();
// Return cached value if available
$cacheEnabled = \Config::inst()->get(get_class(), 'cache_enabled');
$result = isset($_GET['flush']) || !$cacheEnabled ? null : $cache->load($key);
if ($result) {
return $result;
}
// Fallback to generate result
$result = parent::getContent($key, $callback);
$cache->save($result, $key);
return $result;
}
public function getContent($key, $callback)
{
// Bypass rate limiting if flushing, or timeout isn't set
$timeout = \Config::inst()->get(get_class(), 'lock_timeout');
if (isset($_GET['flush']) || !$timeout) {
return parent::getContent($key, $callback);
}
// Generate result with rate limiting enabled
$limitKey = $this->getCacheKey($key);
$cache = $this->getCache();
if ($lockedUntil = $cache->load($limitKey)) {
if (time() < $lockedUntil) {
// Politely inform visitor of limit
$response = new \SS_HTTPResponse_Exception('Too Many Requests.', 429);
$response->getResponse()->addHeader('Retry-After', 1 + $lockedUntil - time());
throw $response;
}
}
// Apply rate limit
$cache->save(time() + $timeout, $limitKey);
// Generate results
$result = parent::getContent($key, $callback);
// Reset rate limit with optional cooldown
if ($cooldown = \Config::inst()->get(get_class(), 'lock_cooldown')) {
// Set cooldown on successful query execution
$cache->save(time() + $cooldown, $limitKey);
} else {
// Without cooldown simply disable lock
$cache->remove($limitKey);
}
return $result;
}
