django-profiletools 0.1.3

Features

• Lazy loading of your authenticated profile record across the request object lifetime. That means in the Python code and the templates.

• Name your profile model anything you want in settings.AUTH_PROFILE_MODULE.

Installation

Get the code:

pip install django-profiletools

Install the middleware and context_processor in your settings.py:

TEMPLATE_CONTEXT_PROCESSORS = (
    ...
    'profiletools.context_processors.fetch_profile',
)

MIDDLEWARE_CLASSES = (
...
'profiletools.middleware.LazyProfileMiddleware',
)

Also in settings.py, set the AUTH_PROFILE_MODULE to your profile model:

AUTH_PROFILE_MODULE = "profiles.Profile"

Based on that, your profile model should resemble something like:

# profiles.models.Profile.py
from django.contrib.auth.models import User
from django.db import models

class Profile(models.Model):

    user = models.OneToOneField(User)

    def __unicode__(self):
        return self.user.username

note: If you don’t use profiles.models.Profile, say members.models.UserProfile go ahead and change the AUTH_PROFILE_MODULE to “members.UserProfile”.

Usage

In your templates:

{{ request.my_profile }}

In your functional views:

profile = request.my_profile

In your class-based views:

profile = self.request.my_profile

Call my_profile as many times as you want, it only loads once. So if you call it 100 times in a view, the SQL SELECT is only done the first time. If no user is found then the my_profile call result is None, which makes it easier to handle templates which need to be able to handle unauthenticated users (like the about page).

note: If you are using the members.UserProfile example, you’ll need to call that by using request.my_userprofile.

Problems with Python’s “is” evaluation and “type” built-in

If you use the is evaluation before doing anything else with the my_profile object, it will behave in a slightly unexpected manner:

The will always return false. For example:

>>> print(request.my_profile is None)
False
>>> p = request.user.get_profile()
>>> print(request.my_profile is p)
False

Also, the type built-in will return a django.utils.functional.SimpleLazyObject object:

>>> print(type)
<class 'django.utils.functional.SimpleLazyObject'>

Keep in mind what is placed in the my_profile value is not a ModelClass instance or None object, but rather a django.utils.functional.SimpleLazyObject.

How to evaluate the my_profile object

Use == to evaluate the my_profile object. This forces the object to be evaluated and won’t return frustrating false-positives.

Inspiration

The lazy loading of profiles was inspired by the rather incredible Noah Kantrowitz.