Editing document with cadaver raises ValueError

[sgillies]

manage_afterPUT is getting a closed file from WebDAVSupport.PUT.

Traceback (innermost last):
  Module ZPublisher.Publish, line 115, in publish
  Module ZPublisher.mapply, line 88, in mapply
  Module ZPublisher.Publish, line 41, in call_object
  Module Products.Archetypes.WebDAVSupport, line 117, in PUT
  Module Products.ATContentTypes.content.document, line 258, in manage_afterPUT
ValueError: I/O operation on closed file

I originally reported this in the Marshall tracker, but Sidnei said it was certainly an ATCT bug.

Using: Plone 2.5.1, Zope 2.9.5, Marshall 0.6.1, python-libxml2 2.6.21.

The bug can be reproduced by following the Marshall tutorial at

 http://plone.org/documentation/tutorial/xml-in-plone-with-marshall

I followed Paul Everitt's steps to the letter.

  $ cadaver http://localhost:8080/plone
  $ edit front-page

The traceback I reported above occurs immediately after writing from vi (cadaver's editor).

[hannosch]

This needs verification against a current Plone release.

[keul]

We were not able to fix this in the TuneUp:

The problem is the use of cElementTree in the atxml.py source. If you don't have the cElementTree but use the python native elementree, you'll get no error.

The problem:

    def processXml(self, context, node):
        """ handle the start of a xml tag with this namespace
        the namespace and the name of the tag are bound to node.

        if this method return false then the node is assumed to
        be junk and it is discarded.
        """ 
        tag, ns = utils.fixtag(node.tag,context.ns_map)
        attribute = self.getAttributeByName( tag )
        if attribute is None:
            return False
        node.attribute = attribute  # <!-- wrong with cElementTree
        return attribute.processXml( context, node)

Doing node.attribute = attribute in bad when the class in implemented in C language. Seems that you can't add additional attributes to native objects.

[keul]

The problem isn't related to the use of Cadaver or editing content using webdav, but only to the internal usage of cElementTree.

Lets open a new ticket for this (#9026).

For users that wanna modify the content with Cadaver: for now simply remove the cElementTree dependency.