[Zope] Error Value: Can't pickle objects in acquisition wrappers

22 May 2006

      Hi,

I have a product with a container class to save a list of groups and
others objects..

The container class is:

class StorageAdapter(ObjectManager, BasicUserFolder):
....
....

this class have a function to add groups like that:

def addGroup(self, id="", nombre="", REQUEST =None):
	"""to add a new group"""

	#create a group
	grupo = Group(id, nombre)
	#add a group to container
	try:
		self._objects=self._objects+
			({'id':id,'meta_type':Group.meta_type},)
		self._setOb(id,grupo)
		object=self._getOb(id) 
		self._p_changed = 1
	except: return MessageDialog(
				title  ='error',
				message='error al añadir grupo',
				)    
	if REQUEST is not None:
                                                REQUEST['RESPONSE'].redirect(self.absolute_url()+'/gestGroupForm') 

The class group is simple like this.

class Group(ObjectManager, BasicUserFolder):
	"""Class Group"""

	meta_type = 'Group'
	title    ='Grupo'

	def __init__(self, id, nombre):

	_debug("init del Group")

	self.id=id 
	self.nombre=nombre 
	#acl to control this group
	f=AclUserFolder()       
	_debug("creo el acl del Group")
	try:    self._setObject('acl_users', f)
	except: return MessageDialog(
			title  ='error Acl Existente',
			message='Este Group ya contiene un ACL',
		)    
	self.__allow_groups__=self.acl_users 

...
...
...

the function addGroup is called from a dtml and the groups are added ok
and later I can view the result perfectly in dtml, but i want to add a
new attribute to class group then in the method __init__  i have add the
sentence:

	self.contacts=[]

this is the only change and then i obtain this error:

2006-05-22T16:29:14 ERROR Zope.SiteErrorLog
http://localhost:8080/prueba/ST/addGroup
Traceback (most recent call last):
  File "/usr/lib/zope/lib/python/ZPublisher/Publish.py", line 119, in
publish
    transactions_manager.commit()
  File "/usr/lib/zope/lib/python/Zope2/App/startup.py", line 234, in
commit
    transaction.commit()
  File "/usr/lib/zope/lib/python/transaction/_manager.py", line 84, in
commit
    self.get().commit(sub)
  File "/usr/lib/zope/lib/python/transaction/_transaction.py", line 381,
in commit
    self._saveCommitishError() # This raises!
  File "/usr/lib/zope/lib/python/transaction/_transaction.py", line 379,
in commit
    self._commitResources()
  File "/usr/lib/zope/lib/python/transaction/_transaction.py", line 424,
in _commitResources
    rm.commit(self)
  File "/usr/lib/zope/lib/python/ZODB/Connection.py", line 462, in
commit
    self._commit(transaction)
  File "/usr/lib/zope/lib/python/ZODB/Connection.py", line 503, in
_commit
    self._store_objects(ObjectWriter(obj), transaction)
  File "/usr/lib/zope/lib/python/ZODB/Connection.py", line 525, in
_store_objects
    p = writer.serialize(obj)  # This calls __getstate__ of obj
  File "/usr/lib/zope/lib/python/ZODB/serialize.py", line 330, in
serialize
    return self._dump(meta, obj.__getstate__())
TypeError: Can't pickle objects in acquisition wrappers.

i don't known where can be my error, if someone can help me.

thank

jose carlos