Simple follower/following relationship in Django

gistfile1.py

$ ./manage.py shell
Python 2.7.5 (default, Aug 25 2013, 00:04:04)
[GCC 4.2.1 Compatible Apple LLVM 5.0 (clang-500.0.68)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> from followers.models import *
>>> john = User.objects.create_user('john', '[email protected]', 'password')
>>> paul = User.objects.create_user('paul', '[email protected]', 'password')
>>> george = User.objects.create_user('george', '[email protected]', 'password')
>>> ringo = User.objects.create_user('ringo', '[email protected]', 'password')

>>> john.following.add(Follower(following=paul))
>>> john.following.add(Follower(following=george))

>>> paul.following.add(Follower(following=john))

>>> ringo.following.add(Follower(following=john))
>>> ringo.following.add(Follower(following=paul))
>>> ringo.following.add(Follower(following=george))

>>> john.followers.all()
[<Follower: paul follows john>, <Follower: ringo follows john>]

>>> paul.followers.all()
[<Follower: john follows paul>, <Follower: ringo follows paul>]

>>> george.followers.all()
[<Follower: john follows george>, <Follower: ringo follows george>]

>>> john.following.all()
[<Follower: john follows paul>, <Follower: john follows george>]

>>> ringo.following.all()
[<Follower: ringo follows john>, <Follower: ringo follows paul>, <Follower: ringo follows george>]

>>> ringo.followers.all()
[]

models.py

from django.db import models
from django.contrib.auth import get_user_model

User = get_user_model()


class Follower(models.Model):
    follower = models.ForeignKey(User, related_name='following')
    following = models.ForeignKey(User, related_name='followers')
    
    class Meta:
        unique_together = ('follower', 'following')

    def __unicode__(self):
        return u'%s follows %s' % (self.follower, self.following)

what is the following in john.following.add(.....) ?

very good

dwwdw

How can we ensure that follower and following are not same ??
Like John follows John doesn't make any sense?

I think you can achieve that programmatically, you just have to check if the user that will follow John is not John itself

I'm currently working on something like that if someone has a better solution I'm interested

what is the following in john.following.add(.....) ?

django ORM provides some attributes and methods we don't have to use it if it makes no sense

Follower.objects.create(follower=foo, following=bar)

Im new to django, but why the class name is Follower? Why not something like ProfileRelation or anything else different? Sr if my question doen't make sense.

Im new to django, but why the class name is Follower? Why not something like ProfileRelation or anything else different? Sr if my question doen't make sense.

You can name it whatever you like. When I wrote this nearly 7 years ago it was just a very quick and dirty example to illustrate a many-to-many relationship between users. I was just quickly answering someone's question on Reddit I think. It seems to have gained some attention lately for some reason.

How can we ensure that follower and following are not same ??
Like John follows John doesn't make any sense?

I would put a check in the Follower.save method to make sure follower and following are not the same user.

Edit: Actually, it's probably better to put that type of validation in a Model Form, or the Model's clean method rather than the Model save method.

def clean(self):
        if self.follower == self.following:
            raise ValidationError("One Cannot follow themselves")

This can be a one way

Yeah that looks pretty clean. No pun intended.

Hi Mike, why did you choose to use ForeignKey instead of ManyToMany Relationship?
A user should be able to follow multiple users and multiple users should also be able to follow a user. Is using a foreignkey not going to restrict it to just one user being able to follow multiple users and multiple users not being able to follow a user...or vice versa?

@Olamidun if I chose a ManyToMany field, that would have to have been implemented directly on the User model which is an unnecessary complication. This method is essentially a through model on a M2M field without declaring it that way.