def referenceRemoved(obj, event):
""" store information about the removed link integrity reference """
assert IReference.providedBy(obj)
assert obj is event.object # just making sure...
if not obj.relationship == referencedRelationship:
return # skip for other removed references
# if the object the event was fired on doesn't have a `REQUEST` attribute
# we can safely assume no direct user action was involved and therefore
# never raise a link integrity exception...
request = aq_get(obj, 'REQUEST', None)
if not request:
return
storage = ILinkIntegrityInfo(request)
storage.addBreach(obj.getSourceObject(), obj.getTargetObject())
def referencedObjectRemoved(obj, event):
""" check if the removal was already confirmed or redirect to the form """
# if the object the event was fired on doesn't have a `REQUEST` attribute
# we can safely assume no direct user action was involved and therefore
# never raise a link integrity exception...
request = aq_get(obj, 'REQUEST', None)
if not request:
return
info = ILinkIntegrityInfo(request)
# first we check if link integrity checking was enabled
if not info.integrityCheckingEnabled():
return
# since the event gets called for every subobject before it's
# called for the item deleted directly via _delObject (event.object)
# itself, but we do not want to present the user with a confirmation
# form for every (referred) subobject, so we remember and skip them...
info.addDeletedItem(obj)
if obj is not event.object:
return
# if the number of expected events has been stored to help us prevent
# multiple forms (i.e. in folder_delete), we wait for the next event
# if we know there will be another...
if info.moreEventsToExpect():
return
# at this point all subobjects have been removed already, so all
# link integrity breaches caused by that have been collected as well;
# if there aren't any (after things have been cleaned up),
# we keep lurking in the shadows...
if not info.getIntegrityBreaches():
return
# if the user has confirmed to remove the currently handled item in a
# previous confirmation form we won't need it anymore this time around...
if info.isConfirmedItem(obj):
return
# otherwise we raise an exception and pass the object that is supposed
# to be removed as the exception value so we can use it as the context
# for the view triggered by the exception; this is needed since the
# view is an adapter for the exception and a request, so it gets the
# exception object as the context, which is not very useful...
raise LinkIntegrityNotificationException(obj)
