'Makes REST API call to list snapshots under a volume.
:param otype: block
:param otypename: either volume or consistency-group should be
provided
:param ouri: uri of volume or consistency-group
:returns: list of snapshots'

def snapshot_list_uri(self, otype, otypename, ouri):

    (s, h) = common.service_json_request(self.ipaddr, self.port, 'GET', Snapshot.URI_SNAPSHOT_LIST.format(otype, otypename, ouri), None)
    o = common.json_decode(s)
    return o['snapshot']
