def modify_snapshot_attribute(snapshot_id, attribute='createVolumePermission', operation_type='add', vars = {})
params = {'SnapshotId' => snapshot_id,
'Attribute' => attribute,
'OperationType' => operation_type}
params.update(amazonize_list('UserId', Array(vars[:user_id]))) if vars[:user_id]
params.update(amazonize_list('UserGroup', Array(vars[:user_group]))) if vars[:user_group]
link = generate_request("ModifySnapshotAttribute", params)
request_info(link, RightBoolResponseParser.new(:logger => @logger))
rescue Exception
on_exception
end