Re: collections containing collections

Thanks, Dave!  I think we are converging on this so I will try and write it as
a proposal.   See following mail.
All the best, Ashok

On 1/29/2013 3:55 PM, David Wood wrote:
> My 2 cents:
>
> On Jan 29, 2013, at 09:32, "Wilde, Erik"<Erik.Wilde@emc.com>  wrote:
>
>> hello ashok.
>>
>> On 2013-01-29 2:21 , "Ashok Malhotra"<ashok.malhotra@oracle.com>  wrote:
>>> 3. Can collections contain collections?
>>> There seems to be agreement that, yes, collections can contain
>>> collections.
>>> There also seems to be agreement that collections are LDPRs and should
>>> be added to collections like any other LDPR.  I think this is settled
>>> but, personally,
>>> I would like to see a line in the spec saying collections can be added to
>>> collections
>>> just like any other LDPR rather than leaving this as an exercise for the
>>> reader.
>> so if collections can contain collections, i can POST a collection
>> representation to a collection. so far so good.
> Yes
>
>> if i GET all members of a
>> collection that is nested, do i GET a mix of collections and members?
> Yes, but just the collections and members that exist at that level.  That is, if a collection "foo" has a member "bar" and a sub collection "baz" then a GET would return those, but not baz's subcollections or members.
>
>> the
>> models of collections and members must have some difference (and hopefully
>> do have quite a bit of overlap), because a collection has a list of
>> members (and a member doesn't have that), and a member has (embedded or
>> linked) content and a collection doesn't have that. if we make collections
>> nestable, then implementations always must be aware that the set of
>> resources returned is heterogeneous (members and/or collections).
> Sure
>
>> if we take the delete model of "always deleting what's managed by the
>> server", then deleting nested collections deletes everything directly or
>> indirectly contained in that tree, i suppose.
> Yes.
>
> Regards,
> Dave
> --
> http://about.me/david_wood
>
>
>> i am not saying that we shouldn't be doing it, but i just want to say that
>> this has  number of non-trivial side-effects on the complexity of the
>> model (i know because we're just going through the exact same exercise
>> internally, where things are even worse because things can be moved and
>> even linked into multiple collections). it certainly is doable, but rather
>> than saying "why not do it?", i think we should only be doing it if we
>> have people enthusiastically saying that this is critically necessary for
>> LDP.
>>
>> cheers,
>>
>> dret.
>>
>>

Received on Tuesday, 29 January 2013 21:01:20 UTC