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Trying to extend AbstractUser to create multiple user types in Django

So I have been searching all around the internet for a full example of how to user AbstractUser when u have at least 2 different models. Didn't find anything conclusive.. at least that would work on latest version of Django (2.0.1).
I have 2 models, teacher and student, and registration needs to be different. Besides username, email, name and surname, I need for example, for the student, to upload a profile picture, email, phone, student_ID. And for teacher, bio, academic title and website. Did I start good ? What is the right approach ?
class Profile(AbstractUser):
photo = models.ImageField(upload_to='students_images')
email = models.EmailField()
phone = models.CharField(max_length=15, )
class Student(Profile):
student_ID = models.CharField(unique=True, max_length=14,
validators=[RegexValidator(regex='^.{14}$',
message='The ID needs to be 14 characters long.')])
def __str__(self):
return self.name
class Teacher(Profile):
academic_title = models.CharField(max_length=30)
bio = models.TextField()
website = models.URLField(help_text="E.g.: https://www.example.com", blank=True)

Your goals can be accomplished using a 'Profile' pattern. You don't necessarily need to use a custom user model for this. But you need to have a single common model to for authentication; you can use the builtin django user for this or a custom class... Your Student and Teacher models should be OnetoOne relationships. This is the recommended solution per the documentation.
If you wish to store information related to User, you can use a OneToOneField to a model containing the fields for additional information. This one-to-one model is often called a profile model, as it might store non-auth related information about a site user.
In your case, you may do something like this:
class StudentProfile(models.Model):
user = models.OneToOneField('User', related_name='student_profile')
# additional fields for students
class TeacherProfile(models.Model):
user = models.OneToOneField('User', related_name='teacher_profile')
# additional fields for teachers
Then you can create your registration forms based on these profile models.
class StudentResistrationForm(forms.ModelForm):
class Meta:
model = StudentProfile
fields = (...)
class TeacherRegistrationForm(forms.ModelForm):
class Meta:
model = TeacherProfile
fields = (...)
You can create the user instance to which the profile is related to at the same time you create the profile. You might do this with formsets, for example.

add
class Meta:
abstract = True
to profile model
and change AbstractUser to models.Model

User with permission to modify only one field of the model in the Django Admin

I have a user named ExpertUser who should only be able to modify an attribute of the called model (money) of the users in the Django Admin.
I have tried adding permissions in the model using the Meta but when entering with that permission I can not modify anything since I do not have access to any user.
My model is this:
class Client(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
money = models.FloatField(default=1000)
def __str__(self):
return self.user.username
class Meta:
permissions = (("can_view_money", "Can view money"),)

Have a look at Django Guardian. That provides more flexibility in assigning permissions on various levels. Django only lets you set permissions at object level, so in your case you were only able to set permission to create/edit/delete Client objects.
http://django-guardian.readthedocs.io/en/v1.4.8/index.html
If that doesn't suffice, there are a few other packages with the desired functionality:
https://djangopackages.org/grids/g/perms/

Create editable set of model objects in django admin

I'm trying to create editable set of objects.
I have Visitor model, which can contain set of models Sibling. But the set may be blank. This set should be editable in Django admin, and, I would like it will be generated by built-in tools.
Here is my approach to do this:
class Sibling(models.Model):
VisitorID = models.ForeignKey('Visitor')
# ... some fields
class Visitor(models.Model):
# ... some fields
Siblings = models.ManyToManyField(Sibling, blank=True)
It is bad way because there are all Siblings from all Visitors in the auto-generated form in django admin, but I want only those which are related to specific Visitor.
Could anyone help me or give advice?

One way achieve this with a Serializer class
class Sibling(models.Model):
VisitorID = models.ForeignKey('Visitor')
# ... some fields
class Visitor(models.Model):
# ... some fields
class VisitorSerializer(serializers.ModelSerializer):
sibling = serializers.RelatedField(source='sibling')
class Meta:
model = Visitor
# List all fields in Visitor plus sibling
fields = ('id', 'somefieldinvisitormodel', 'sibling')
The serializer class allows you to override what's being displayed in admin without having to mess with your models. This also allows you to remove the extra relationship you added within visitor.
This isn't an entirely automated solution, but it's close.

Defining the name of a ManyToOne relationship in Django

I would like to define a django model which has many-to-one relationship with itself. It is a user profile, connected as a OneToOne field with the authentication user model. I would like to save which user (if any) was the one who referred the 'current' user to my system. This means I have the following definition:
class UserProfile(models.Model):
user = models.OneToOneField(User, blank=True, related_name='profile')
class Meta:
abstract = True
class SpecificUserProfile(UserProfile):
referrer = models.ForeignKey('self')
I saw the django defaults to naming the set of referenced models by the name of the class with a suffix _set. I believe I will be getting something along the lines of specific_user_profile_set. I would much prefer to have it named u1.referrer and u2.referred or u2.referred_set. Is there any way this can be achieved?

related_name='profile'
This is the argument to define a name for any related field, so:
class SpecificUserProfile(UserProfile):
referrer = models.ForeignKey('self', related_name='referred')

Django Rest Framework not saving foreign key for a small number of requests

I am using Django Rest Framework to provide API to a mobile app. I have two models, Order and User. Order has a foreign key relation to User.
For about 1% or so of all my order objects, the User field is null. I've been testing this behavior using cURL.
If I do a cURL without a user object, it tells me "This field is required".
If done with a wrong user object, it tells me that the object does not exist. Both of these are the intended and expected behaviors.
I'm trying to figure out how it is possible for some of the Order objects to be saved without a user field. Is there something I'm not taking into account?
My views:
class OrderList (generics.ListCreateAPIView):
model = Order
serializer_class = OrderSerializer
And serializer:
class OrderSerializer (serializers.ModelSerializer):
user = serializers.SlugRelatedField(slug_field = 'user')
partial = True
class Meta:
model = Order
Models:
class User (models.Model):
uid = models.CharField(max_length =200, unique=True)
class Order (models.Model):
uid = models.ForeignKey (User, related_name = "orders", verbose_name = "User",blank=True, null=True)

You could use two different ModelSerializer classes, one for creation, that makes sure, that an Order object can't be created without a related User and one for updating orders, that passes required=False to the related field's constructor, so that you still can save existing orders that haven't a related User.

Try adding default=None to your models.ForeignKey declaration. You could also just create an anonymous user in the users table and when the user isn't specified it could set the anonymous user instead.