Re: [ZODB-Dev] Persistent object has empty __dict__ for a little while
On Wed, Jan 06, 2010 at 06:37:31PM -0500, Jim Fulton wrote: __dict__ is a special variable. Accessing it doesn't cause an object to be activated. Rather than doing: clone.__dict__.update(field.__dict__) I would do: clone.__setstate__(field.__getstate__) Nitpick: clone.__setstate__(field.__getstate__()) Alternatively, you can assure that field is acticated first, using _p_activate or by accessing an attribute. Regards, Marius Gedminas -- Those of you thinking that grown men with serious jobs should be above such phrases as way friendlier should realise that in the 21st century, adult appropriation of infantilisms is de rigueur, innit? -- Stuart Jeffries signature.asc Description: Digital signature ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] Persistent object has empty __dict__ for a little while
On Thu, Jan 7, 2010 at 7:04 AM, Marius Gedminas mar...@gedmin.as wrote: On Wed, Jan 06, 2010 at 06:37:31PM -0500, Jim Fulton wrote: __dict__ is a special variable. Accessing it doesn't cause an object to be activated. Rather than doing: clone.__dict__.update(field.__dict__) I would do: clone.__setstate__(field.__getstate__) Nitpick: clone.__setstate__(field.__getstate__()) Yup. Thanks. Jim -- Jim Fulton ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] Persistent object has empty __dict__ for a little while
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Hash: SHA1
Martin Aspeli wrote:
Hi,
This one is pretty high no the list of weirdest things to have happened
to me in a while. Basically, I have a persistent object that has an
empty __dict__() on the first request, until it suddenly decides to have
data again.
I'm on ZODB 3.9.3, using Zope 2.12 and Plone 4. I have a persistent
object, /plone/portal_registry:
class Registry(registry.Registry, SimpleItem):
pass
The base class is:
class Registry(Persistent):
def __init__(self):
self._records = Records(self)
Records is:
class Records(Persistent):
__parent__ = None
def __init__(self, parent):
self.__parent__ = parent
self.data = OOBTree()
def __getitem__(self, name):
return self.data.__getitem__(name)
The BTree contains string keys and Record objects as values. Record is:
class Record(Persistent):
__name__ = u
__parent__ = None
field = None
__parent__ is set to records.__parent__, which is going to be the
Registry object.
field is set to a special persistent field class inheriting from
zope.schema's fields, but mixing in persistence. In this case, I have a
list field:
class PersistentField(persistent.Persistent):
Base class for persistent field definitions.
class PersistentCollectionField(PersistentField,
zope.schema._field.AbstractCollection):
class List(PersistentCollectionField, zope.schema.List):
pass
I then have some code like this:
def cloneField(self, field):
clone = field.__class__.__new__(field.__class__)
clone.__dict__.update(field.__dict__)
for name, attr in field.__dict__.items():
if IField.providedBy(attr):
clone.__dict__[name] = self.cloneField(attr)
return clone
This is used like so:
registry = getUtility(IRegistry) # persistent/local
clone = self.cloneField(registry.records[recordName].field)
This seems to work always *except* on the first request immediately
after starting up Zope. In this case, field.__dict__ is {}. If I poke at
it long enough in pdb, it suddenly springs into life and contains values
again.
Can anyone enlighten me as to:
- why this may happen
- how I can ensure it stops happening :-)
You have a ghost, likely: try getting it to unghostify by accessing an
attribute, or calling '_p_activate' (accessing '__dict__' doesn't
provoke the auto-activation).
Tres.
- --
===
Tres Seaver +1 540-429-0999 tsea...@palladion.com
Palladion Software Excellence by Designhttp://palladion.com
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Re: [ZODB-Dev] Persistent object has empty __dict__ for a little while
On Wed, Jan 6, 2010 at 10:40 AM, Martin Aspeli optilude+li...@gmail.com wrote:
Hi,
This one is pretty high no the list of weirdest things to have happened
to me in a while. Basically, I have a persistent object that has an
empty __dict__() on the first request, until it suddenly decides to have
data again.
I'm on ZODB 3.9.3, using Zope 2.12 and Plone 4. I have a persistent
object, /plone/portal_registry:
class Registry(registry.Registry, SimpleItem):
pass
The base class is:
class Registry(Persistent):
def __init__(self):
self._records = Records(self)
Records is:
class Records(Persistent):
__parent__ = None
def __init__(self, parent):
self.__parent__ = parent
self.data = OOBTree()
def __getitem__(self, name):
return self.data.__getitem__(name)
The BTree contains string keys and Record objects as values. Record is:
class Record(Persistent):
__name__ = u
__parent__ = None
field = None
__parent__ is set to records.__parent__, which is going to be the
Registry object.
field is set to a special persistent field class inheriting from
zope.schema's fields, but mixing in persistence. In this case, I have a
list field:
class PersistentField(persistent.Persistent):
Base class for persistent field definitions.
class PersistentCollectionField(PersistentField,
zope.schema._field.AbstractCollection):
class List(PersistentCollectionField, zope.schema.List):
pass
I then have some code like this:
def cloneField(self, field):
clone = field.__class__.__new__(field.__class__)
clone.__dict__.update(field.__dict__)
for name, attr in field.__dict__.items():
if IField.providedBy(attr):
clone.__dict__[name] = self.cloneField(attr)
return clone
This is used like so:
registry = getUtility(IRegistry) # persistent/local
clone = self.cloneField(registry.records[recordName].field)
This seems to work always *except* on the first request immediately
after starting up Zope. In this case, field.__dict__ is {}. If I poke at
it long enough in pdb, it suddenly springs into life and contains values
again.
Can anyone enlighten me as to:
- why this may happen
- how I can ensure it stops happening :-)
__dict__ is a special variable. Accessing it doesn't cause an object
to be activated.
Rather than doing:
clone.__dict__.update(field.__dict__)
I would do:
clone.__setstate__(field.__getstate__)
Alternatively, you can assure that field is acticated first, using
_p_activate or by accessing an
attribute.
Jim
--
Jim Fulton
___
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