[z3] [Fwd: Re: [Zope3-Users] sqlos - getting factory of NoneType]

[Brian Sutherland]

On Sat, Jan 07, 2006 at 06:26:19PM +0000, Christian Lück wrote:
> Hi
> 
> The problem with sqlos seems: It does only work if ONE AND ONLY ONE
> factory for the content component (interface) in question is registered.
> And this one-and-only factory has to be registered with the
> zcml-directive in a special sqlos namespace, ie.
> 
>   <sqlos:factory
>       id="quotationtool.BookSQLObject"
>       component=".book.Book"
>       title="BookSQLObject"
>       description="A book object for the sql resourcedb."
>       />
> 
> When a second factory is registered for the same interface, ie.
> 
>   <factory
>       id="quotationtool.BookWithInitialValues"
>       component=".book.BookFactory"
>       title="BookWithInitialValues"
>       description="A factory for book object with initial values."
>       />
> 
> sqlos fails to get the objects stored on the database (you get blank
> browser pages).
> The reason seems to be the implementation of
> sqlos.container.SQLObjectContainer, which maps between sql-unique-keys
> (SQLObject-names) and zope-object-names. The mapping mechanism makes use
> of the factory.

Yes, I have seen this problem before. You cannot mix sqlos:factory and
factory and expect things to work.

And yes, this is a _big_ problem which I think requires a re-think of
how we do this. But that re-think is not yet thunk.

So please try this patch (untested). If it works for you, I will add it
to the source.

Index: container.py
===================================================================
--- container.py        (revision 21506)
+++ container.py        (working copy)
@@ -106,7 +106,9 @@
         (name, object) for the objects that appear in the folder.
         """
         for factoryName in self.allowedFactories():
-            factory = zapi.getUtility(IISQLObject, factoryName, context=self)
+            factory = zapi.queryUtility(IISQLObject, factoryName, context=self)
+            if factory is None:
+                continue
             for obj in factory.select():
                 name = '%s.%s' % (factoryName, obj.id)
                 yield (name, contained(obj, parent=self, name=name))

> This way it works, I see the sql-objects and can even edit them :) - But
> works yust to run into the next bigger problem... (I can't create
> objects due to rollback problems) :((((

If you post a traceback here, there is a chance someone can give you a
quick answer.

-- 
Brian Sutherland

Metropolis - "it's the first movie with a robot. And she's a woman.
              And she's EVIL!!"