[Zope3-dev] future of fssync (was: RE: [SpringCleaning07])

[Uwe Oestermeier]

Jim Fulton <jim at zope.com> on Mittwoch, 24. Januar 2007 at 16:48 Uhr +0100
wrote:
>
>Maybe, but I like your idea of using utilities below.  My original  
>thinking was
>along these lines: fssync should strive to serialize "all" object  
>data.  (Note that it isn't always obvious what data is intrinsic to  
>an object.)  I felt therefore, that inheriting synchronization  
>adapters would be bad.  If someone created a subclass and forgot to  
>create an adapter, then their data would be serialized incompletely.   
>I like the idea of using named utilities, using dotted class names as  
>utility ids.  See below.

Ok, I will give named utilities a try.
>
>> 	- Can zope.app.fssync.fspickle be replaced by zope.xmlpickle? (It  
>> seems
>> that fspickle preserves location ids but it does not seem to  
>> preserve the
>> order of dict items)
>
>I'm a bit rusty on this.  I would think that these can be combined.   
>It should, I think, be possible to generate location-aware pickles  
>and then use zmlpickle to represent these as XML.  The trick, I  
>think, would be use the pickle persistent-reference mechanism to  
>refer to other objects by location, when necessary.  I say this  
>without looking at the code. :)  If you need me to dig deeper, I'll  
>try to find time to do so.

I found such a combination in zope.fssync.server.entryadapter. There a
location-aware pickle was created by fspickle.dumps and converted via
xmlpickle.toxml. This version generated xmlpickles with changing dict
representations which in turn led to false alarms that objects had been
modified. 

I will try to combine the xmlpickle._PicklerThatSortsDictItems with the
fspickle.ParentPersistentIdGenerator and see whether this solves the
problem. If this doesn't work, I will ask you for further assistance.
		
>
Uwe
>



________________________________________________________________
Dr. Uwe Oestermeier
Institut für Wissensmedien
Knowledge Media Research Center
Konrad-Adenauer-Str. 40
D-72072 Tuebingen
Germany
u.oestermeier at iwm-kmrc.de
Tel. +49 7071 979-208
Fax +49 7071 979-100