Comment 0 for bug 1676437

Please see here: https://specs.openstack.org/openstack/api-wg/guidelines/errors.html. Currently we're returning errors that look like:

{
    "message": "<error message>",
    "code": 400
}

This is not robust enough to meet the needs of clients, especially when the request generates several errors that we wish to communicate in a uniform, machine-friendly way.