[Kolab-devel] No x-uid please. (was: Re: [NEW KEP] KEP #17: Kolab XML Format 3.0)

[Jeroen van Meeuwen (Kolab Systems)]

On 2012-03-13 13:22, Christian Mollekopf wrote:
> On 2012-03-13 1:18, Jeroen van Meeuwen (Kolab Systems) wrote:
>> If a Kolab client aware of the meaning of an x-uid attribute value
>> reads a distribution list object edited by a client that has no
>> understanding of the x-uid attribute value, the behaviour between 
>> the
>> two clients is going to be different.
>>
>> Remember we've been there before and it wasn't pretty.
>>
>> Different clients showing different behaviour, precedence rules,
>> conflict detection between asynchronous edits and conflict resolving
>> all kick in here, and for no good reason.
>>
>
> No they don't, the behavior is very clear, there is no possibility 
> for
> conflicts and we don't need precedence rules or conflict resolving.
>
> There is a mailto uri which serves the purpose of having an email
> distribution list and is not directly connected to a contact. There 
> is
> no need or desire to synchronize that to a Contact instance.
> The x-uid property serves the additional purpose of being able to 
> link
> a Contact object to that member, so it's easy to get to it. That is 
> an
> additional usecase and there is no need to have the properties
> synchronized in any way.
>

If the contact is referred to in a distribution list "Kolab Systems 
Employees", and the actual contact object has "Jeroen van Meeuwen (Kolab 
Systems)" as the display name for one of its identities, and 
"vanmeeuwen at kolabsys.com" as the email address for that identity;

- A client might update a distribution list to refer to the recipient 
address used in the distribution list as 'mailto:Jeroen 
<kanarip at kolabsys.com>' while the x-uid remains the same, causing 
de-synchronized state.

- A client might update the actual contact object's display name (to 
"Jeroen van Meeuwen") or email address (to 
"jeroen.vanmeeuwen at kolabsys.com") corresponding with the identity, while 
a mailto: value for the member element in a distribution list remains 
"mailto: Jeroen van Meeuwen (Kolab Systems) <vanmeeuwen at kolabsys.com>", 
causing de-synchronized state.

- A client not aware of the x-uid attribute, nor what it's value means, 
has *no* chance in either of the aforementioned cases to refer back to 
the contact object.

Kind regards,

Jeroen van Meeuwen

-- 
Systems Architect, Kolab Systems AG

e: vanmeeuwen at kolabsys.com
m: +44 74 2516 3817
w: http://www.kolabsys.com

pgp: 9342 BF08