public function setHeaders(EventInterface $event)
{
$method = $event->getRequest()->getMethod();
// Obviously we shouldn't bother doing any HTTP caching logic for non-GET/HEAD requests
if ($method !== 'GET' && $method !== 'HEAD') {
return;
}
$response = $event->getResponse();
$headers = $event->getResponse()->headers;
// Imbo defaults to 'public' as cache-control value - if it has changed from this value,
// assume the resource requested has explicitly defined its own caching rules and fall back
if ($headers->get('Cache-Control') !== 'public') {
return;
}
// Get configured HTTP cache defaults from configuration, then apply them
$config = $event->getConfig()['httpCacheHeaders'];
if (isset($config['maxAge'])) {
$response->setMaxAge((int) $config['maxAge']);
}
if (isset($config['sharedMaxAge'])) {
$response->setSharedMaxAge($config['sharedMaxAge']);
}
if (isset($config['public']) && $config['public']) {
$response->setPublic();
} else {
if (isset($config['public'])) {
$response->setPrivate();
}
}
if (isset($config['mustRevalidate']) && $config['mustRevalidate']) {
$headers->addCacheControlDirective('must-revalidate');
}
}
