def get_metrics(self, path, from_time, to_time, metrics, view, params=None):
    """
    Generic function for querying metrics.

    @param from_time: A datetime; start of the period to query (optional).
    @param to_time: A datetime; end of the period to query (default = now).
    @param metrics: List of metrics to query (default = all).
    @param view: View to materialize ('full' or 'summary')
    @param params: Other query parameters.
    @return: List of metrics and their readings.
    """
    if not params:
      params = { }
    if from_time:
      params['from'] = from_time.isoformat()
    if to_time:
      params['to'] = to_time.isoformat()
    if metrics:
      params['metrics'] = metrics
    if view:
      params['view'] = view
    resp = self.get(path, params=params)
    return types.ApiList.from_json_dict(resp, self, types.ApiMetric)