[Zope] Posible memory leak?

[Dieter Maurer]

Gabriel Genellina wrote at 2003-11-29 01:33 -0300:
 > At 27/11/2003 21:17, you wrote:
 > >I added a step in my manage_addTopic() script like
 > >this to make a local reference to the "View" attrib I'm
 > >trying to acquire:
 > >
 > >ob = Topic(...)
 > >ob.ViewAlias = self.View
 > >self._setObject(id, ob)
 > >ob = self._getOb(id)
 > >
 > >View is a PersistentMapping, so I presume it will act like
 > >a normal mutable Python object (so when I make changes
 > >to its contents, they'll show up in the alias).  I'll have
 > >to test this, anyway, to make sure, of course.
 > >
 > >In the __setstate__ method, Topic computes using the
 > >ViewAlias which is a local attribute:
 > >
 > >for view in self.ViewAlias.keys():
 > >         #... do some stuff with this view info
 > >         pass
 > 
 > Is this correct?

This looks okay.

 > Or there is a memory leak here?

I do not see one (which does not necessarily mean there are none).

 > In a previous post 
 > http://mail.zope.org/pipermail/zope/2002-January/107054.html Max M 
 > maxm at mxm.dk said:
 > 
 > >If your item is subclassing persistent you should expect them to stay in
 > >the zodb. And then you should not add them to a list in your own
 > >product, but create a subclass of ObjectManager and use the _setObject()
 > >method to add the item instances.
 > >
 > >Else your item class should not subclass persistent.

I do this routinely. There is only one problem: when you change
the list, you must tell the object that you did this.
The problem disappears when you use a persistent object, such
as a "PersistentList".

Your code does not use the problematic case.


 >  From this and other sources I've been told *not* to store a Persistent 
 > object as an attribute of another object,

Precisely, this does "ObjectManager": it stores its content items
(persistent objects) as attributes of itself.
As you see by this prominent example: there is not problem to do this.


-- 
Dieter