Re: [ZODB-Dev] Persistent object has empty __dict__ for a little while
On Thu, Jan 7, 2010 at 7:04 AM, Marius Gedminas 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
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 Wed, Jan 6, 2010 at 10:40 AM, 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 :-)
__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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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 Design"http://palladion.com
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Re: [ZODB-Dev] Persistent object has empty __dict__ for a little while
2010/1/6 Martin Aspeli :
> 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 :-)
I don't know if this should ever happen when you access
persistentobj.__dict__, but it sounds as if it is in the ghost state.
What is clone._p_state at this point (-1 would be a ghost object, 0 =
normal object, 1 = modified object).
You could do clone._p_activate() first.
Laurence
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