[Zope3-dev] LocationProxy and breadcrumbs

[Garrett Smith]

I'm trying to implement 'user folders' by way of principal annotations. 
I know historically this sort of thing was done using a 'Members' 
folder,  but this seems less than elegant given the principal 
annotations service.

I want users to be able to access their folders using this sort of path:

   /@@myfolder/...

I've create a view for ISite and written a traverser that looks for 
'index.html' and returns a location proxied Folder whose actual 
container is the user's principal annotations.

This works pretty well traversing from top to bottom. However, 
breadcrumbs are wrong -- the traversal back up the path leads to the 
annotations service, site manager, etc.

I've written my own version of LocationProxy that wraps all of the 
children down a traversal so that the current context's parent is within 
the wrapped hierarchy and not the persisted hierarchy. This works, but 
is fragile given the widespread direct use of '__parent__' throughout 
the code.

I don't think this case is unusual - it should be possible, if not easy, 
to create alternative paths to objects. I don't see this as a 
multi-parent scenario but merely a way to present the same data via 
different paths.

I was hoping someone could offer some insights to this. Perhaps I'm 
overlooking an existing facility.

  -- Garrett