64      * @param callable $httpHandler callback which delivers psr7 request
68     public function fetchAuthToken(callable $httpHandler = null)  argument
74         $auth_token = $this->fetcher->fetchAuthToken($httpHandler);
100      * @param callable $httpHandler An HTTP handler to deliver PSR7 requests.
103     public function getClientName(callable $httpHandler = null)  argument
112         return $this->fetcher->getClientName($httpHandler);
169     public function getProjectId(callable $httpHandler = null)  argument
178         return $this->fetcher->getProjectId($httpHandler);
186      * @param callable $httpHandler callback which delivers psr7 request
194         callable $httpHandler = null  argument
218             $httpHandler