Comment 5 for bug 1400366

It's a list of currently appropriate sort keys that successfully pass trough the pagination check:
_decl_class_registry
_extra_keys
_sa_class_manager
checksum
container_format
created_at
deleted
deleted_at
disk_format
id
is_public
locations
members
metadata
min_disk
min_ram
name
owner
properties
protected
size
status
tags
updated_at
virtual_size

The first three and metadata belong to model class only and they not presented in db. So sorting by these keys will raise ArgumentError with 500 status code from glance.