Call stacks for Model classes

[malhar]

So, there is a huge Django app with multiple classes in Model. I am interested in getting call stacks of some classes. I have few questions in the approach and few questions regarding the implementation. I am using Django 1.4.20 and python 2.7

1. What if we decide to write a decorator for the class/ methods? 
Ex. 

@trackitdown
Class A(models.Model):

or 

@trackitdown

def some_method(): # method in models.py

This is because I do not want to disturb the existing code. I wish to achieve following-
I. If it is a class, track all "calls" whenever QuerySetAPI methods, save, delete is called. 
II. while doing following-

objects =classWhichIsAManager()# overriding default manager Custom manager

this should be decorator's task.
III. override using get_query_set() , and save(), delete()

How do you see this approach? I obviously was not able to implement this because of peculiar behavior of Model and ModelBase.

2. Is it okay to decorate a class, define decorator as a class and override methods in it? How much is this encouraged?

3. If I use Mixins, and try to implement the same, I still do not get how do we override 

objects=classWhichIsAManager()

outside the model class? that too without loosing attributes of original model class.

4. Having said this, I wish to implement a library which will take care calls stacks of model classes/ methods. 

Is there a fundamental flaw in my approach? I can see that I am trying to play with some unknown business of ModelBase(Foreign Key constraints, etc) New approaches and comments are equally welcome!

[Shai Berger]

Hi,

Please ask questions about developing with Django on the django-users group.
This group is for discussions about the development of Django itself.

(as a general rule: decorating single methods should work fine; trying to use
decorators on model classes will probably be painful. These classes use
special metaclasses which make them behave differently in many respects).

Thanks,
Shai.