django-eav provides an Entity-Attribute-Value storage model for django apps.
For a decent explanation of what an Entity-Attribute-Value storage model is, check Wikipedia.
This software was inspired / derived from the excellent eav-django written by Andrey Mikhaylenko.
There are a few notable differences between this implementation and the eav-django implementation.
- This one is called django-eav, whereas the other is called eav-django.
- This app allows you to to 'attach' EAV attributes to any existing django model (even from third-party apps) without making any changes to the those models' code.
- This app has slightly more robust (but still not perfect) filtering.
You can install django-eav directly from guthub:
pip install -e git+git://github.com/mvpdev/django-eav.git#egg=django-eav
Django Sites Framework
As of Django 1.7, the Sites framework is not enabled by default; Django-EAV requires this framework. To enable the sites framework, follow these steps:
django.contrib.sites to your INSTALLED_APPS setting. Be sure to add sites to the installed apps list BEFORE eav!
SITE_ID = 1
eav to your
INSTALLED_APPS in your project's
settings.py file. Be sure to add eav to the installed apps list AFTER the sites framework!
Register your model(s)
Before you can attach eav attributes to your model, you must register your model with eav:
>>> import eav >>> eav.register(MyModel)
Generally you would do this in your
models.py immediate after your model
declarations. Alternatively, you can use the registration decorator provided:
from eav.decorators import register_eav @register_eav() class MyModel(models.Model): ...
Create some attributes
>>> from eav.models import Attribute >>> Attribute.objects.create(name='Weight', datatype=Attribute.TYPE_FLOAT) >>> Attribute.objects.create(name='Color', datatype=Attribute.TYPE_TEXT)
Assign eav values
>>> m = MyModel() >>> m.eav.weight = 15.4 >>> m.eav.color = 'blue' >>> m.save() >>> m = MyModel.objects.get(pk=m.pk) >>> m.eav.weight 15.4 >>> m.eav.color blue >>> p = MyModel.objects.create(eav__weight = 12, eav__color='red')
Filter on eav values
>>> MyModel.objects.filter(eav__weight=15.4) >>> MyModel.objects.exclude(name='bob', eav__weight=15.4, eav__color='red')