Motivation
----------

In an effort to provide useful constructs in each of our projects, a
need arose for a base model class in Django to provide some common
fields and functionality as an abstract base model, including adding
arbitrary properties to the model that can also persist.

By moving this functionality into a standalone module, we are now
able to import and use this base model class across all of our
projects.

Currently the BaseModel class contains the following extra fields in
an abstract Django Model:

- time_created = DateTimeField(auto_now_add=True)
- time_modified = DateTimeField(auto_now=True)
- last_modified_by = ForiegnKey(django.contrib.auth.models.User)
- attributes = GenericRelation(ModelAttribute)

ModelAttribute is simple model that utilizes Django's ContentTypes
and generic relations to facilitate creating arbitrary name/value
pairs associated with any model that inherits from BaseModel.

Installation
------------

Simply add this module to your Python path, then add the following to
your Django settings.py INSTALLED_APPS section:

django_base_model

Once that is in place run the following management command to update
your database:

./manage.py syncdb

Usage
-----

Whenever you would like to create a model with the additional fields,
do the following:

from django_base_model.models import BaseModel


class MyModel(BaseModel):
    ...

By default, BaseModelManager is already associated with the "objects"
property of any model that inherits from BaseModel. If you plan on
overriding or adding some additional methods on the ModelManager
associated with the model, then you'll also want to make sure your
custom ModelManager inherits from BaseModelManager:

class MyModelManager(BaseModelManager):
    ...

And in your model do the following:

class MyModel(BaseModel):
    ...
    objects = MyModelManager()
    ...

Lastly, if you would like support for keeping track of who made the
last change to the object in the Django admin and seeing when the
model was created and last modified for any model that inherits from
BaseModel, you can also setup a ModelAdmin object that will help take
care of that for you:

from django_base_model.admin import BaseModelAdmin


class MyModelAdmin(BaseModelAdmin):
    ...

There are three methods on the BaseModelAdmin class that you can
utilize for things such as the list_display property on a ModelAdmin
object:

 - last_modified_by_name (formatted Django User name)
 - last_edited (formatted time_modified)
 - created_on (formatted time_created)

These methods will display more reasonably formatted versions of the
values stored with the model, but the BaseModelAdmin display makes no
assumptions of what you would like to appear in the object listing
pages of the Django admin so you will have to add them in yourself
to the properties on your custom ModelAdmin class.  Please consult
the Django documentation for more details on how to do so here:

https://docs.djangoproject.com/en/1.4/ref/contrib/admin/