[Zope-dev] Re: zope.sqlalchemy, integration ideas

[Martijn Faassen]

Brian Sutherland wrote:
[snip]
> I'll note that there is a difference between where things are published
> (IAbsoluteURL) and where you should go to find their canonical
> representation.
> 
> One problem I've found with using IAbsoluteURL and location proxies is
> getting the object directly from the database. In this situation you
> don't have an LocationProxy and IAbsoluteURL doesn't work.
> 
> It's pretty nasty when IAbsoluteURL sometimes works and sometimes
> doesn't for what essentially is the same object.

Agreed, we should ideally always get our objects from the db already 
properly wrapped in a location proxy (or providing ILocation directly). 
I think we can do this with containers based on relations; those 
containers are under our control after all.

Is a direct one on one relation possible in SQLAlchemy? I.e. an object 
foo that has an attribute 'bar' that is another ORM-ed object. If so we 
also need to take care of that case somehow.

This is the "it should work like ZODB-backed objects" pattern I've been 
trying to follow as a design guideline. Since for contained objects I 
can always get the URL, it should work that way for RDB-based contained 
objects too.

Regards,

Martijn