def list_metrics(self, page_size=None, page_token=None):
        """List metrics for the project associated with this client.

        See
        https://cloud.google.com/logging/docs/reference/v2/rest/v2/projects.metrics/list

        :type page_size: int
        :param page_size:
            Optional. The maximum number of metrics in each page of results
            from this request. Non-positive values are ignored. Defaults to a
            sensible value set by the API.

        :type page_token: str
        :param page_token:
            Optional. If present, return the next batch of metrics, using the
            value, which must correspond to the ``nextPageToken`` value
            returned in the previous response.  Deprecated: use the ``pages``
            property of the returned iterator instead of manually passing the
            token.

        :rtype: :class:`~google.api_core.page_iterator.Iterator`
        :returns: Iterator of :class:`~google.cloud.logging.metric.Metric`
                  accessible to the current client.
        """
        return self.metrics_api.list_metrics(self.project, page_size, page_token)