the final answer is:
    def get_size ( self ) :
        return ''

found thanks to ajung's WebDAV logger

robert
----- Original Message -----
From: "Robert Rottermann" <robert@[...].ch> 
To: "Robert Rottermann" <robert@[...].ch> ; <zope@[...].org>
Sent: Wednesday, April 03, 2002 12:15 AM
Subject: Re: [Zope] webdav: collection does not work when I use file type
object as baseclass


>  I tested things some more.
>  It works most of the time. However sometimes I get
>  following error in the web dav client (Dreamweaver):
>  "could not understand server response"
> 
>  So I still would appreciate a hint very much.
> 
>  Robert
>  ----- Original Message -----
>  From: "Robert Rottermann" <robert@[...].ch>
>  To: "Robert Rottermann" <robert@[...].ch>; <zope@[...].org>
>  Sent: Tuesday, April 02, 2002 11:57 PM
>  Subject: Re: [Zope] webdav: collection does not work when I use file type
>  object as baseclass
> 
> 
>  > I have been digging into the problem some more.
>  > The culprit seems to be the method get_size()
>  > This Method is not defined for a collection (I did not find it  at
least)
>  > but for most of the "file" types.
>  > Webdav probably expects in getsize to find the length of the directory
but
>  > gets the length something else.
>  >
>  > Does anybody know what webdav expects as result of get_size()?
>  >
>  > I tried with
>  >     def get_size ( self ) :
>  >         return self.objectItems()
>  >
>  > this works but ...
>  >
>  >
>  > Robert
>  > ----- Original Message -----
>  > From: "Robert Rottermann" <robert@[...].ch>
>  > To: <zope@[...].org>
>  > Sent: Tuesday, April 02, 2002 11:10 PM
>  > Subject: [Zope] webdav: collection does not work when I use file type
>  object
>  > as baseclass
>  >
>  >
>  > > Hi there,
>  > >
>  > > I am creating a product that has a folderish and a file type aspect.
>  > > I therefore use both ObjectManager and DTMLMethod as its base classes.
>  > >
>  > > When I do that, I can not use Webdav to access folders which contains
>  > > instances of my product anymore.
>  > > If I get rid of the DTMLMethod as base class things work fine again.
>  > >
>  > > Is such a combination of base classes sensible?  If yes, what must I
do
>  to
>  > > have webdav working?
>  > >
>  > > thanks for your help.
>  > >
>  > > Robert
>  > > www.redcor.ch
>  > >
>  > >
>  > >
>  > > _______________________________________________
>  > > Zope maillist  -  Zope@[...].org
>  > > http://lists.zope.org/mailman/listinfo/zope
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>  > >
>  >
>  >
> 
> 
>  _______________________________________________
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