def _get_schema(self):
        time_now = int(datetime.datetime.utcnow().strftime('%s'))
        if ((self.column_families is None or
             (time_now - self.last_schema_sync_time < 3600))):
            return False
        url = 'http://%s:%i/%s/keyspaces' % (self.config['host'],
                                             int(self.config['port']),
                                             self.config['cluster_id'])
        try:
            response = urllib2.urlopen(url)
        except Exception, err:
            self.log.error('%s: %s', url, err)
            return False

        try:
            result = json.load(response)
            column_families = []
            for ks in result:
                i = []
                for cf in result[ks]['column_families']:
                    i.append("%s.%s" % (ks, cf))
                column_families.append(i)
            self.column_families = ','.join(sum(column_families, []))
            self.log.debug('DseOpsCenterCollector columnfamilies = %s',
                           self.column_families)
            self.last_schema_sync_time = time_now
            return True

        except (TypeError, __HOLE__):
            self.log.error(
                "Unable to parse response from opscenter as a json object")
            return False
dataset/ETHPy150Open python-diamond/Diamond/src/collectors/dseopscenter/dseopscenter.py/DseOpsCenterCollector._get_schema