[Zope-dev] Is _getOb() best way to grab a ref to a particular object?

[Andrew Wilcox]

Right, what I'm looking for is to reference an absolute object, sort of
like saying "/usr/bin/sendmail" in the filesystem.  The note about avoiding
an acquisition wrapper by using aq_base is helpful.  Hmm, I don't know why
I thought I needed _getOb().  Some test I did that confused me because the
result was being rendered, and I didn't realize that was happening in the
publisher.  I think.

Anyway, let's say I want to grab /topfolder/subfolder/myobj, and I know
they exist, so I'm not worried about acquisition along the way.  So what
I've got now is:

    obj = REQUEST.PARENTS[-1].topfolder.subfolder.myobj

or

    na_obj = REQUEST.PARENTS[-1].topfolder.subfolder.myobj.aq_base

Ok, that's pretty straightforward!

Thanks!

Andrew


At 09:25 AM 11/22/99 -0500, Brian Lloyd wrote:
>> I need to grab a reference to a particular object in the ZODB from an
>> external method, bypassing acquisition.  Is this the right 
>> way to do it:
>> 
>>     def test(self, REQUEST=None):
>>         """doc string"""
>>         myobj =
>> REQUEST.PARENTS[-1].aTopLevelFolder.anotherFolder._getOb('id_o
>> f_myobj')
>>         ...do stuff with myobj: myobj.title, myobj.index_html,
>> myobj.property = 123 ...
>
>Maybe, maybe not... _getOb will not return an acquired object, but
>if the object exists it _will_ be returned as a "wrapped" object
>so acquisition will be preserved in the result. I'm not clear from
>your example whether this is what you want. If you want the *resulting*
>object to be non-acquiring, you'll want to do something like:
>
>def test(self, REQUEST=None):
>  """ """
>  # get object named 'foo' from self, but dont allow it
>  # to be found via acquisition.
>
>  obj=self._getOb('foo')
>
>  # while we know that foo is not acquired from above, it 
>  # is still wrapped in the context of 'self', so to disable 
>  # acquisition we need to unwrap it.
>
>  non_aquiring_obj=obj.aq_base
>
>  ...
>
>Hope this helps!
>
>
>Brian Lloyd        brian@digicool.com
>Software Engineer  540.371.6909              
>Digital Creations  http://www.digicool.com 
>
>
>
>