null]; /** * Fetches the auth token. In this case it returns a null value. * * @param callable $httpHandler * @return array */ public function fetchAuthToken(callable $httpHandler = null) { return $this->token; } /** * Returns the cache key. In this case it returns a null value, disabling * caching. * * @return string|null */ public function getCacheKey() { return null; } /** * Fetches the last received token. In this case, it returns the same null * auth token. * * @return array */ public function getLastReceivedToken() { return $this->token; } /** * This method has no effect for AnonymousCredentials. * * @param array $metadata metadata hashmap * @param string $authUri optional auth uri * @param callable $httpHandler callback which delivers psr7 request * @return array updated metadata hashmap */ public function updateMetadata($metadata, $authUri = null, callable $httpHandler = null) { return $metadata; } /** * This method always returns null for AnonymousCredentials. * * @return string|null */ public function getQuotaProject() { return null; } }