Hi there.
Possibly a rather stupid question, but I currently have some issues when
using multiple inheritance and subclassed SQLObjects.
As an overview, the idea is to override certain aspects of SQLObjects to
intercept various calls for event logging.
Additionally, event-logged classes may or may not also require additional
parameters which are defined in another class and then implemented using
multiple inheritance.
We're talking about a fairly large number of objects, so I don't feel like
writing individual definitions for each class I want to log for, nor do I
want to add individual properties for every class which requires them.
As an idea, I'll assume the following:
Class A - Event logging SQLObject class
Class B - Additional method / properties Object class.
Class C - A class requiring event logging and additional properties.
That said, an example:
#-------------------------------------
import logging
from sqlobject import *
from sqlobject.inheritance import InheritableSQLObject
log = logging.getLogger('testpython')
class A(InheritableSQLObject):
def _init(self, *args, **kw):
log.debug("A - _init")
InheritableSQLObject._init(self, *args, **kw)
class B(Object):
def _init(self, *args, **kw):
self.additonalproperty = "bogusstring" + self.id
class C(A, B):
bogusfield = IntCol()
def _init(self, *args, **kw):
log.debug("C - _init")
A._init(self, *args, **kw)
B._init(self, *args, **kw)
#-------------------------------------
Now, a couple of reasons I've used the following:
A._init has to be called before C._init, as self.id does not exist in B
before A._init has been executed.
But, if we execute the following, we see that although C._init is called
once, A._init executes twice.
#-------------------------------------
c = C.get(1)
2007-03-14 11:45:34,513 testpython DEBUG C - _init
2007-03-14 11:45:34,513 testpython DEBUG A - _init
2007-03-14 11:45:34,674 testpython DEBUG A - _init
#-------------------------------------
Further playing around and overriding the __init__ methods of the classes
A, B and C we have the following:
#-------------------------------------
import logging
from sqlobject import *
from sqlobject.inheritance import InheritableSQLObject
log = logging.getLogger('testpython')
class A(InheritableSQLObject):
def __init__(self, *args, **kw):
log.debug("A - __init__")
InheritableSQLObject.__init__(self, *args, **kw)
def _init(self, *args, **kw):
log.debug("A - _init")
InheritableSQLObject._init(self, *args, **kw)
class B(Object):
def _init(self, *args, **kw):
self.additonalproperty = "bogusstring" + self.id
class C(A, B):
bogusfield = IntCol()
def __init__(self, *args, **kw):
log.debug("C - __init__")
A.__init__(self, *args, **kw)
def _init(self, *args, **kw):
log.debug("C - _init")
A._init(self, *args, **kw)
B._init(self, *args, **kw)
#-------------------------------------
2007-03-14 11:45:34,513 testpython DEBUG C - __init__
2007-03-14 11:45:34,513 testpython DEBUG A - __init__
2007-03-14 11:45:34,513 testpython DEBUG C - _init
2007-03-14 11:45:34,513 testpython DEBUG A - _init
2007-03-14 11:45:34,674 testpython DEBUG A - __init__
2007-03-14 11:45:34,674 testpython DEBUG A - _init
Naturally, this makes the use of subclassing SQLObject slightly
unsatisfactory for event logging for my purposes, as we're talking about
numerous log events for every single operation.
Is there something I am missing here ? Or have I got some misconception
about how to implement this ?
Any assistance / advice appreciated.
Regards,
Ian
-------------------------------------------------------------------------
Take Surveys. Earn Cash. Influence the Future of IT
Join SourceForge.net's Techsay panel and you'll get the chance to share your
opinions on IT & business topics through brief surveys-and earn cash
http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV
_______________________________________________
sqlobject-discuss mailing list
sqlobject-discuss@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/sqlobject-discuss
