[Zope3-dev] Form framework, adapters and pau

[Jim Fulton]

Dominik Huber wrote:
> A few months ago the following code block was removed in editview.py, 
> editwizard.py and schemadisplay.py (revision 29418):
> 
>    def _setUpWidgets(self):
>        adapted = self.schema(self.context)
>        if adapted is not self.context:
>            if not ILocation.providedBy(adapted):
>                adapted = LocationProxy(adapted)
>            adapted.__parent__ = self.context
>        self.adapted = adapted
>        setUpEditWidgets(self, self.schema, source=self.adapted,
>                         names=self.fieldNames)
> 
> As a consequence each trusted adapter class should now implement 
> ILocation

One could, as an alternative, use an non-trusted adapter
that is public and rely on the underlying object protection.

 > that the TrustedAdapterFactory can set the location of adapter
> instances correctly. Otherwise, only the global authentication is 
> involved and the edit view fails if any local principal tries to edit a 
> certain field (security.canWrite(source, name) in zope.app.form.utility 
> line 207).
> 
> I would like to revert those changes. IMO a framework like the form 
> framework knows the context (location) and adapts that context to a 
> certain schema. If the following procedures depends on location 
> information, the framework itself should pass such informations in a 
> smart way. It's an unnecessary <se?lp=ende&p=/Mn4k.&search=unnecessary> 
> expense <se?lp=ende&p=/Mn4k.&search=expense> to force all schema 
> adapters to implement ILocation:
> 
> - The solution using the location proxy seems fairly famillar
>  compared with the container framework and containment that does not
>  provide ILocation.

Except that the object being location proxied is already security
proxied.  Location proxies were not designed to proxy security-proxied
objects.

> - An adapter that implements more than one interface cannot be registered
>  with the implicit adapts and implements informations.

True.

> - A regular schema does not extend ILocation therefore it is not obvious to
>  write an adapter implementing ILocation.

True.

> Any objections?

Yes. :)

Why not simply use an untrusted public adapter?

Jim

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