I am slowly coming to grips with using external methods to reach into the ZODB. Right now, I am trying to create an instance of a folderish ZClass and then populate it with (pre-existing) images from elsewhere in the ZODB. (The following URL has been very helpful http://www.zope.org/Members/tazzzzz/addZClasses.) Excerpts of my external method: # create an instance of MyClass container=parent.Control_Panel.Products.MyProduct.MyClass(container_id) # make container a child object of parent parent._setObject(container_id, container) # set various attributes of container container.id = container_id container.foo = foobar # assume image points to a proper ZClass Image container.manage_addImage(image.id, image.data, '') A few questions: *) The final manage_addImage call occassionally fails with a seek error on image.data. <!-- Error type: AttributeError Error value: seek --> File /usr/local2/Zope/lib/python/OFS/Image.py, line 265, in _read_data (Object: default_image) AttributeError: (see above) I have verified that image is a valid Image and that: repr(image) = <Image instance at 8551e90> len(image.data) = 13611 type(image.data) = <extension class Acquisition.ImplicitAcquirerWrapper at 40160680> repr(image.content_type) = 'image/jpeg' Can someone offer advice as to why my read of image.data fails? *) What happens to container if I *don't* execute parent._setObject(container_id, container)? Doing this, I notice that the size of Data.fs does not increase (before running external method compard to after). Does this mean that Zope has somehow recognized that container doesn't have a parent and deleted it? I'm worried that I could corrupt my database during development of external methods that create/delete/manipulate the ZODB. Cheers, Darran. -- Darran Edmundson [Darran.Edmundson@anu.edu.au]