function CacheTagsChecksumTrait::isValid

Implements \Drupal\Core\Cache\CacheTagsChecksumInterface::isValid()

File

core/lib/Drupal/Core/Cache/CacheTagsChecksumTrait.php, line 105

Class

CacheTagsChecksumTrait

A trait for cache tag checksum implementations.

Namespace

Code

public function isValid($checksum, array $tags) {
    // Any cache reads in this request involving cache tags whose invalidation
    // has been delayed due to an in-progress transaction are not allowed to use
    // data stored in cache; it must be assumed to be stale. This forces those
    // results to be computed instead. Together with the logic in
    // ::getCurrentChecksum(), it also prevents that computed data from being
    // written to the cache.
    if (!empty(array_intersect($tags, $this->delayedTags))) {
        return FALSE;
    }
    return $checksum == $this->calculateChecksum($tags);
}