Question

I would like to have getObjPositionInParent as a sort criteria in a collection. I configured it as “available” in the site setup for collection views. But it is not available. Did I forget something?

Answer 1

You didn’t forget anything, but found a bug in Plone. The GopipIndex from plone.app.folder is used for the getObjPositionInParent index. But this index type is not registered for any collection criteria. The criterion registry in Products.ATContentTypes.criteria needs to include a mapping for the GopipIndex. Likely adding it to the SORT_INDICES list would be the right thing to do. To do this from outside, you can do something like:

# Make sort criteria available for the GopipIndex
from Products.ATContentTypes.criteria import _criterionRegistry
crit_reg = _criterionRegistry
crit_id = 'ATSortCriterion'
index = 'GopipIndex'

indices = crit_reg.criterion2index.get(crit_id, ())
crit_reg.criterion2index[crit_id] = indices + (index, )

value = crit_reg.index2criterion.get(index, ())
crit_reg.index2criterion[index] = value + (crit_id, )