I think required attributes aren't handled optimally in MBUI forms.

Server side attribute description provides three related flags:

• required := attribute must be set, or an alternative must be set
• alternatives := list of alternatives
• nillable := !required || count(alternative-attributes) > 0

Currently, attributes marked as required and having alternatives are treated as optional in HAL:

• no asterisk (probably good),
• placed into "Optional" group,
• it is not enforced that the attribute or an alternative has to be set (on the server this is enforced).

I suggest following behaviour instead:

• still no asterisk (so a user doesn't get the feeling that he has to fill in both alternative attributes),
• placed into "default" group (so that it's by default visible when creating a resource, and the eventual error message is immediately visible without having to open the "Optional" group when editing a resource),
• it is enforced that a required attribute or its' alternative has to be set.

cmiranda@redhat.com, hpehl@redhat.com what do you think?