9:52 a.m.
On 12/10/14, 9:22 AM, Kabir Khan wrote:
> On 9 Dec 2014, at 21:00, Brian Stansberry <brian.stansberry(a)redhat.com> wrote:
>
> Off and on we've had discussions around the idea of "attribute
groups".
> We've got some use cases that are crying out for such a thing[1], so I'd
> like to propose doing something concrete but simple for these for WF 9,
> ideally in the next month.
>
> A big part of my goal here is to ensure that whatever we do doesn't
> preclude something more advanced in any next generation management
> stuff, e.g. David's stuff.
>
> PART I Concepts
>
> 1) What is an attribute group?
>
> The "attribute group" concept I propose is simply a collection of
> attributes associated with the same resource type that are independently
> configurable but are statically declared to be conceptually related. The
> group has a name, and members. The name provides a brief indication of
> the nature of the relationship.
>
> The goal is to provide information to the user to help them better
> understand the relationship between attributes. In particular,
> management tools could use this information to visually present related
> attributes together, e.g. in a tab or other grouping widget in the web
> console.
>
> 2) What isn't an attribute group?
>
> Something relevant to writes.
>
> 3) Why would I use a child resource instead of an attribute group?
>
> Because the attributes control a discrete piece of functionality and you
> need to be able to turn that on or off as a unit. So you add/remove the
> resource.
>
> 4) Why would I use a complex attribute with a bunch of fields instead of
> n>1 simple attributes in a group.
>
> a) Because the attributes control a discrete piece of functionality and
> you need to be able to turn that off as a unit. So users can undefine
> the complex attribute.
>
> b) Because it's a common use case that modifications to n>1 of the
> fields should be done atomically and you don't want to force users to
> use a CLI batch. So you let them use write-attribute and specify the
> value of all the fields.
Why not something along the lines of :write-attribute-group(name=mygroup, value={attr1=a,
attr2=b})?
Internally that could create a composite for us, giving complex attribute functionality
while avoiding the messy resource descriptions
On the branch of the thread where I'm discussing with Tomaz, he raised
the same idea, which I think is a good one. I think a "write-attributes"
with no relationship to attribute-group makes more sense though.
--
Brian Stansberry
Senior Principal Software Engineer
JBoss by Red Hat