[Zope] ZCA / five / zcml overrides issue...

[Bruno Desthuilliers]

Hi there

I probably missed some point about how this Component Architecture /
ZCML config stuff is supposed to work with zope 2.10+ (actually Zope
2.10.5), ,so any hint or pointer welcome...

Here's my problem:

I use a third-part product (ContentMirror) that defines some interfaces
and their implementations, and register the adapters in it's
configure.zcml. It also defines a couple zcml directives, with actions
that call  component.getMultiAdapter to retrieve the implementation for
these interfaces.

I'd like to provide my own implementation for one of these interfaces.
So I wrote the implementation, added an <include> of the ContentMirror
package in my own configure.zcml, and an overrides.zcml with the
registration directive for my own implementation:

<configure xmlns="http://namespaces.zope.org/zope">
  <!-- use our own PeerFactory implementation instead -->
  <adapter
     for="ore.contentmirror.interfaces.IMirrored
ore.contentmirror.interfaces.ISchemaTransformer"
     provides="ore.contentmirror.interfaces.IPeerFactory"
     factory=".peer.ManagedSchemaPeerFactory"
     />
</configure>


Bad luck, the whole thing then crashes when ContentMirror's own zcml
directive are executed - looks like none of the adapter are effectively
registred by that time (it of course worked just fine - but with the
original IPeerfactory implementation - before I added this override).

Here's the traceback I get at startup:

2010-03-23 11:41:41 ERROR Application Couldn't install Five
Traceback (most recent call last):
  File "/home/zope/share/Plone-3.0.6/lib/python/OFS/Application.py",
line 786, in install_product
    initmethod(context)
  File
"/home/zope/share/Plone-3.0.6/lib/python/Products/Five/__init__.py",
line 28, in initialize
    zcml.load_site()
  File "/home/zope/share/Plone-3.0.6/lib/python/Products/Five/zcml.py",
line 53, in load_site
    _context = xmlconfig.file(file)
  File
"/home/zope/share/Plone-3.0.6/lib/python/zope/configuration/xmlconfig.py",
line 581, in file
    context.execute_actions()
  File
"/home/zope/share/Plone-3.0.6/lib/python/zope/configuration/config.py",
line 612, in execute_actions
    callable(*args, **kw)
  File
"/home/zope/share/Products/ProductsOTHERS/ContentMirror/eggs/ore.contentmirror-0.5.2b2-py2.4.egg/ore/contentmirror/loader.py", 


line 39, in load
    peer_class = self.peer( instance, transformer )
  File
"/home/zope/share/Products/ProductsOTHERS/ContentMirror/eggs/ore.contentmirror-0.5.2b2-py2.4.egg/ore/contentmirror/loader.py", 


line 51, in peer
    interfaces.IPeerFactory )
  File "/home/zope/share/Plone-3.0.6/lib/python/zope/component/_api.py",
line 103, in getMultiAdapter
    raise ComponentLookupError(objects, interface, name)
ConfigurationExecutionError:
zope.component.interfaces.ComponentLookupError: ((<ATDocument at
transient>, <ore.contentmirror.transform.SchemaTransformer object at
0xb6e028c>), <InterfaceClass ore.contentmirror.interfaces.IPeerFactory>,
u'')
  in:
  File
"/home/zope/share/Products/ProductsOTHERS/ContentMirror/eggs/ore.contentmirror-0.5.2b2-py2.4.egg/ore/contentmirror/content.zcml", 


line 3.4-3.80
      <ore:mirror
content="Products.ATContentTypes.content.document.ATDocument" />



I obviously did something wrong - but what ???

TIA
-- 
bruno desthuilliers
bruno at websiteburo.com