Develop Reference

Using User Profile automatically load information into form fields

In my pervious question I asked how I can automatically save the user submitting the form. I found the form_valid method to be the best in that case. However in my models I also have a user profile model like this
models.py
....
class Profile(models.Model):
user = models.OneToOneField(User,on_delete=models.CASCADE)
title = models.CharField(max_length=24)
first_name = models.CharField(max_length=35)
last_name = models.CharField(max_length=35)
email = models.EmailField(max_length=64)
phone_number = models.CharField(max_length=12)
department = models.ForeignKey(Department,null=True,on_delete=models.SET_NULL)
supervisor = models.ForeignKey('self',blank=True,null=True,on_delete=models.SET_NULL)
...
As you can see I used the One to One method to make my UserProfile
As before in my models.py I have my reports model
...
class Report(models.Model):
id = models.UUIDField(primary_key=True,default=uuid.uuid1,editable=False)
department = models.ForeignKey(Company,null=True,on_delete=models.SET_NULL)
user= models.ForeignKey(User,on_delete=models.PROTECT)
submission_date= models.DateField(auto_now=True) #invisible to user
submission_time = models.TimeField(auto_now=True) #invisible to ,user
date = models.DateField(default=now,blank=False)
time = models.TimeField(default=now,blank=False,help_text="hh:mm:ss")
location = PlainLocationField()
building = models.ForeignKey(bld,null=True,on_delete=models.SET_NULL)
size = models.PositiveIntegerField()
notes = models.TextField(blank=True)
def __str__(self):
return f'{self.date} {self.time} ({self.department})
...
My question how I can make it so that the department field will load from the user profile? I would hope to eventually make it possible for users in the same department to be able to view and update each others Reports.
As before:
form.py
class ReportForm(forms.ModelForm):
class Meta:
model = Report
fields = '__all__'
location = PlainLocationField()
def redirect():
return redirect("Report")
views.py
class ReportCreate(LoginRequiredMixin,CreateView):
Template = "templates\reports\Report.html"
model = Report
fields = '__all__'
def form_valid(self, form):
form.instance.user = self.request.user
form.instance.save()
return super(ReportCreate, self).form_valid(form)
def get_success_url(self):
return reverse('Report')
def get_absolute_url(self):
return reverse('Report', kwargs={'pk':self.pk})

I advise you to use related_name in your ForeignKeys. Set the department field of both models as following:
class Profile(models.Model):
...
department = models.ForeignKey(Department, null=True, on_delete=models.SET_NULL, related_name='profiles')
...
class Report(models.Model):
...
department = models.ForeignKey(Department, null=True, on_delete=models.SET_NULL, related_name='reports')
...
From now on, Department objects that are related to User.Profile you can access like that:
Department.profiles.all() # it returns QuerySet of all related to Department Profile objects
Department.reports.all() # it returns QuerySet of all related to Department Report objects
And you can use it in making QuerySet for user:
Report.objects.filter(department=self.request.user.profile.department)
# it returns all Report objects, that have exactly the same department as the user
Or using our new relationship:
department = self.request.user.profile.department
reports_for_user = department.reports.all()
But I can see one problem. You are using Company model for ForeignKey in Report. It has to be the same Department model for both Profile and Report models for such easy option to work. Also you definitely should not mix naming in single project. You can set relation with Company as another field:
company = models.ForeignKey(Company, null=True, on_delete=models.SET_NULL)

Here are some steps to help you autofill some fields:
Get the user from self.request.user. How to access current user in Django class based view
Get the profile: get user profile in django
Pass the required fields as context variables: https://www.geeksforgeeks.org/how-to-pass-additional-context-into-a-class-based-view-django/
Pass it into javascript. How can I pass my context variables to a javascript file in Django?
Set the value like this: Set the value of an input field
DONE!

Django: implement multiple user levels / roles / types

I have been using Django for quite a while but never have I thought of this until now.
Currently, I have a project that contains different user levels. Usually, in my past experience, I only developed systems using Django with only two user levels which are superuser and normal/regular user. So my question is what are the effective ways to present these different user levels in the model/database? Here, I'm going to use a school system as an example and also provide some of my initial thoughts on implementing it.
User levels:
Admin (superuser & staff)
Principal
Teacher
Students
Method #1: Add new tables based on each user level
from django.contrib.auth.models import AbstractUser
from django.db import models
class User(AbstractUser):
user = models.CharfieldField(max_length = 10, unique = True)
class Admin(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE, primary_key=True)
class Pricipal(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE, primary_key=True)
class Teacher(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE, primary_key=True)
class Student(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE, primary_key=True)
Method #2: Add additional user types attributes in the User model
from django.contrib.auth.models import AbstractUser
from django.db import models
class User(AbstractUser):
user = models.CharfieldField(max_length = 10, unique = True)
is_superuser = models.BooleanField(default = False)
is_staff = models.BooleanField(default = False)
is_principal = models.BooleanField(default = False)
is_teacher = models.BooleanField(default = False)
is_student = models.BooleanField(default = False
'''
User table in DB:
user | is_superuser | is_staff | is_principal | is_teacher | is_student
'''
My thoughts:
In Method #1, as the built-in User model has two fields, is_staff and is_superuser, Is it possible to implement/change the fields into a SuperUser/Admin table as in the example above? This means that when I create an admin/superuser, I want it to add a new row into the Admin table, instead of adding a new user and updating the user's is_superuser and is_staff fields into 1 in the built-in User model.
In Method #2, the problem with it is that tables with different access privileges are directly connected to it. For example, Salary model (which cannot be accessed by Student user) has a direct link with the User model (contains Student user).
I hope I am able to get some insights and also a proper effective way of implementing this so that to prevent any implementation inconvenience and mistakes in the future. Thank you very much.

I think you are in the right path with method #2. It is lighter, and more straightforward.
I would not use a custom "user-like" model for each permission level. Over-complicated, does not scale, and multiply the number of queries, with no very benefit for your problem. Not your UML schema but its content must guarantee your permission requirements.
If the permission levels are not mutual-exclusive :
from django.db import models
from django.contrib.postgres.fields import ArrayField
class User(AbstractUser):
ADMIN = 0
PRINCIPLE = 1
TEACHER = 2
STUDENT = 3
USER_LEVEL_CHOICES = (
(ADMIN, "Admin"),
(PRINCIPLE, "Principle"),
(TEACHER, "Teacher"),
(STUDENT, "Student"),
)
status = ArrayField(
models.IntegerField(choices=USER_LEVEL_CHOICES, blank=True, default=STUDENT),
)
But you need to have a wider reflexion.
I think you are talking about two separate problems : polymorphism, and permissions
Polymorphism :
Polymorphism is the ability of an object to take on many forms. For a Django model, it can be done with many strategies : OneToOneField -as you mentioned- multi-table inheritance, abstract models, or proxy-models.
Very good resources : this article, and Django doc about model inheritance
This very complex problem all refer to : how much your several forms of a same entity are similar, or different. And which operations are particularly similar or different (data shape, querying, permission, ...etc)
Permissions design :
You can choose among several patterns
Model-oriented permission : A user is granted "add", "view", "edit" or "delete" permission to a Model. This is done in Django with the built-in Permission model, that have a ForeignKey to ContentType
Object-oriented permission : A user is granted "add", "view", "edit" or "delete" permission for each Model instance. Some packages provides this ability, django-guardian for example.
Rule-oriented permission : A user is granted permission to a Model instance through custom logic instead of M2M table. The django rules package provide this kind of architecture.

You can create from AbstractUser (a full User model, complete with fields, including is_superuser and is_staff) a Profile and then, once you have the profile, give the chance of users to create other type of profile (Student, Teacher or Principle) which could have functionalities of its own.
For instances, in your models.py
class Profiles(AbstractUser):
date_of_birth = models.DateField(max_length=128, blank=True, null=True, default=None, verbose_name=_(u'Date of birth'))
principle = models.OneToOneField(Principles, null=True, blank=True, verbose_name=_(u'Principles'), on_delete=models.CASCADE)
teacher = models.OneToOneField(Teachers, null=True, blank=True, verbose_name=_(u'Teachers'), on_delete=models.CASCADE)
student = models.OneToOneField(Students, null=True, blank=True, verbose_name=_(u'Students'), on_delete=models.CASCADE)
class Meta:
db_table = 'profiles'
verbose_name = _('Profile')
verbose_name_plural = _('Profiles')
To that model you can add class methods, such as
def is_teacher(self):
if self.teacher:
return True
else:
return False
Then, your Teachers model could look like this
class Teachers(models.Model):
image = models.FileField(upload_to=UploadToPathAndRename(settings.TEACHERS_IMAGES_DIR), blank=True, null=True, verbose_name=_('Teacher logo'))
name = models.CharField(blank=False, null=False, default=None, max_length=255, validators=[MaxLengthValidator(255)], verbose_name=_('Name'))
street = models.CharField( max_length=128, blank=False, null=True, default=None, verbose_name=_('Street'))
created_by = models.ForeignKey('Profiles', null=True, blank=True, on_delete=models.SET_NULL)

One of the methods that I used in several projects is this (pseudo code):
class User(AbstractUser):
ADMIN = 0
PRINCIPLE = 1
TEACHER = 2
STUDENT = 3
USER_LEVEL_CHOICES = (
(ADMIN, "Admin"),
(PRINCIPLE, "Principle"),
(TEACHER, "Teacher"),
(STUDENT, "Student"),
)
user_level = models.IntgerField(choices=USER_LEVEL_CHOICES)
def lvl_decorator():
def check_lvl(func):
def function_wrapper(self, actor, action_on, *args, **kwargs):
if 'action_lvl' not in action_on: # then action_on is user
if actor.user_lvl < action_on.user_lvl:
return True
return False
else: # then action_on is action of some kind for that user (you can add action_lvl to ... and pas them to this wapper)
if actor.user_lvl < action_on.action_lvl:
return True
return False
return function_wrapper
return check_lvl
Then you can write wrapper function with this logic for any action check if action level is bigger than user level e.g.: if someone wants to change superuser password he/she should be logged-in with level-0-user but for changing normal user's password he/she should be level 0, 1. This logic also can be applied to class, functions, etc actions.
Create base class and then add lvl_decorator to it then inherent from it => this keeps your code super clean and prevents further copy paste.
example of what i mean:
def lvl_decorator():
def check_lvl(func):
def function_wrapper(self, actor, action_on, *args, **kwargs):
if 'action_lvl' not in action_on: # then action_on is user
if actor.user_lvl < action_on.user_lvl:
return True
return False
else:
if actor.user_lvl < action_on.action_lvl:
return True
return False
return function_wrapper
return check_lvl
class BaseClass(type):
def __new__(cls, name, bases, local):
for attr in local:
value = local[attr]
if callable(value):
local[attr] = lvl_decorator()
return type.__new__(cls, name, bases, local)
# in other locations like views.py use this sample
class FooViewDjango(object, ApiView): # don't remove object or this won't work, you can use any Django stuff you need to inherent.
__metaclass__ = BaseClass
def baz(self):
print('hora hora')
Use this base class in any where you want.

How to avoid this redundancy when using Django model inheritance?

All pages in my Django website have a footer link "Feedback/Questions". If the new person comes to the site and clicks that link, they should be directed to a form with a pulldown to indicate if they have feedback versus a question and fields for their email address and their feedback or question. The page will have a simple header all non-authenticated users will see. On the other hand, if a site member signs in and is authenticated, they should see the same form but without the email field (since I already know their email address) and a different authenticated header containing the site's internal navbar, buttons, etc.
My initial thought was to create an abstract class FeedbackQuestion:
class FeedbackQuestion(models.Model):
submission_type = ... (type, i.e. feedback or question)
submission_text = ... (actual feedback or question)
...
class Meta:
abstract = True
Then I'd create two separate concrete child classes:
class AnonFeedbackQuestion(FeedbackQuestion):
email = models.EmailField(...)
class Meta:
db_table = anon_feedback_question
class AuthFeedbackQuestion(FeedbackQuestion):
user = models.ForeignKey(User, related_name="user")
class Meta:
db_table = auth_feedback_question
These two classes would have their own model forms:
class AnonFeedbackQuestionForm(ModelForm):
class Meta:
model = AnonFeedbackQuestion
fields = ['submission_type', 'submission_text', 'email']
class AuthFeedbackQuestionForm(ModelForm):
class Meta:
model = AuthFeedbackQuestion
fields = ['submission_type', 'submission_text']
The problem I forsee is that I will have to do the following in my view that displays the feedback form:
def get_feedback_questions(request, template):
if request.method == 'POST':
...
if request.user.is_authenticated():
form = AuthFeedbackQuestionForm(request.POST)
else:
form = AnonFeedbackQuestionForm(request.POST)
if form.is_valid():
(process form)
...
else:
if request.user.is_authenticated():
form = AuthFeedbackQuestionForm(request.POST)
else:
form = AnonFeedbackQuestionForm(request.POST)
...
context = {'form': form}
return render(request, template, context)
Having to repeat these if/then/else blocks to identify which form to use seems rather inelegant. Is there a better, cleaner "Django" way to do this?
Thanks!

I wouldn't subclass your models - if it's an anonymous question you could just include a user attribute as well as an email attribute on one model with blank=True and null=True:
class FeedbackQuestion(models.Model):
submission_type = ... (type, i.e. feedback or question)
submission_text = ... (actual feedback or question)
email = models.EmailField(..., blank=True, null=True)
user = models.ForeignKey(User, related_name="user", blank=True, null=True)
...
class Meta:
abstract = True
This way you can add either the email for an anonymous user's feedback/question or the user if they're authenticated.
Then I'd combine your forms into one including the email field, but remove the email field depending on if the user is authenticated (see this answer):
def __init__(self, *args, **kwargs):
self.user = kwargs.pop('user', None)
super(UserForm, self).__init__(*args, **kwargs)
if self.user:
# For logged-in users, email field not necessary
self.fields.pop('email')
else:
# Otherwise, the field needs to be required
self.fields['email'].required = True
Then you just need to make sure you create the user appropriately as you clean the form's data (e.g., make sure the email address isn't already taken, etc.)

Access field from a related UserProfile model

I am having some trouble in selecting data in Django.
models.py
class Location(models.Model):
user = models.ForeignKey(User, on_delete=models.CASCADE)
my_location = models.CharField(max_length=120, choices=LOCATION_CHOICES)
update_date = models.DateField(auto_now=True, null=True)
date = models.DateField()
def __str__(self):
return self.my_location
class UserProfile(models.Model):
user = models.ForeignKey(User)
user_base = models.CharField(max_length=120, choices=LOCATION_CHOICES)
user_position = models.CharField(max_length=120)
user_phone = models.PositiveIntegerField()
slug = models.SlugField()
def save(self, *args, **kwargs):
self.slug = slugify(self.user)
super(UserProfile, self).save(*args, **kwargs)
def __unicode__(self):
return self.user.username
views.py
def index(request):
locations = Location.objects.order_by('-update_date')
context = {'locations': locations}
return render(request, 'index.html', context)
I was able to show the email from User module but what I really want to show is the data from UserProfile.
Please, any advice.
Thank you.

Instead of using
user = models.ForeignKey(User)
use:
user = models.OneToOneField(User)
One-to-one relationships suit better your case. If you use them, your User model will automatically get a userprofile attribute that you can use like this:
>>> user = User.objects.get(...)
>>> user.userprofile.user_phone
12345
You can also consider writing a custom User model, so that you can get rid of UserProfile.
Bonus tip: PositiveIntegerField is not the right field for a phone number. Leading zeroes have a meaning. Also, PositiveIntegerField have a maximum value. Use CharField instead.

Use a OneToOneField
To make it more direct, I'd make the UserProfile have a OneToOneField relationship with User, instead of a ForeignKey. Because this will mean that a given user can only have one profile.
class Location(models.Model):
user = models.OneToOneField(User)
In which case you can access it easier with location.user.userprofile.your_field
Using a custom MyUser model
If you want to make this even more direct, you could make a custom MyUser model that will contain both the fields from User and UserProfile.
It would go roughly like this:
from django.contrib.auth.models import AbstractBaseUser
class MyUser(AbstractBaseUser):
# Adding your custom fields
user_base = models.CharField(max_length=120, choices=LOCATION_CHOICES)
user_position = models.CharField(max_length=120)
user_phone = models.CharField(max_length=120)
slug = models.SlugField()
class Location(models.Model)
user = OneToOneField(MyUser) # Using your custom MyUser model
This allows a more direct access, e.g. location.user.user_phone instead of location.user.userprofile.user_phone
I've only provided pseudocode, please refer to Django documentation
Using a ForeignKey means you may have multiple profiles
In the other case where a user may have multiple user profiles, you then have the burden on you to select which profile to use to pull the relevant data from, because then the relationship would be user.userprofile_set, a set that you will have to filter/index to choose from.

How to handle multiple user types with Django 1.7 user model

I am very new to Python and Django. I am trying to setup user model for different roles like Agents, Brokers, Company and Customer. Each of these roles can register with the site as a user. Then Agents and Brokers can have public facing profile pages.
Do I have to use custom user model or built in user model will work? I have additional properties like license, location, languages, photo etc for Agents and Brokers.
class MyUser(AbstractBaseUser):
AGENTS = 'AG'
BROKERS = 'BR'
COMPANY = 'CP'
CUSTOMER = 'CM'
ROLE_IN_CHOICES = (
(AGENTS, 'Agent'),
(BROKERS, 'Broker'),
(COMPANY, 'Company'),
(CUSTOMER, 'Customer'))
first_name = models.CharField(max_length=100, blank=True)
second_name = models.CharField(max_length=100, blank=True)
middle_name = models.CharField(max_length=100, blank=True)
dob = models.DateField(blank=True, null=True)
phone = models.CharField(max_length=10)
secondary_phone = models.CharField(max_length=10, blank=True, null=True)
......
#property
def is_agent(self):
return self.role in (self.AGENTS)
#property
def is_customer(self):
return self.role in (self.CUSTOMER)
#property
def is_broker(self):*
return self.role in (self.BROKER)
#property
def is_company(self):
return self.role in (self.COMPANY)
....
Can I not use base User model and achieve same? Am I on write track?
How do I create public facing pages for these roles (Agents, Brokers)?
This is my first attempt with Python and Django. I am using Django 1.7.7 with Python 3.4

You should extend from the Django User model instead and add the extra fields you need:
from django.contrib.auth.models import User as Auth_User
class User(Auth_User):
# add your extra fields here like roles, etc
phone = CharField(max_length=20, null=True, blank=True)
# add your extra functions
def extra_user_function(self):
return "This is an extra function"
This way you have your own fields and also the Django User fields...
After migrating, if you check the database, you'll have auth_user and your_app_user tables.
Just bare in mind that request.user will only give you the super fields... In order to get the extended class you'll need
User.objects.get(id=request.user.id)
The latest will only have the extra fields and its id will be the same as the auth.User if you don't add any auth_user by itself.
Attention: this is important!
Otherwise request.user.id and your_app.User.id don't match, therefore User.objects.get(id=request.user.id) won't work and you'll have to query the db to find the your_app.User.id
User.object.get(user_ptr_id = request.user.id)
Other things to consider
This will work:
# you_app.User objects gets vars from auth.User
user = User.objects.get(id=request.user.id)
first_name = user.first_name
But this won't work
# auth.User trying to get a function from your_app.User
user = request.user
user.extra_user_function()
So the User model could be something like this:
import os
from django.contrib.auth.models import User as Django_User
from django.db.models import CharField, ImageField
class User(Django_User):
phone = CharField(max_length=20, null=True, blank=True)
observations = CharField(max_length=2048, null=True, blank=True)
picture = ImageField(upload_to='users', default='default/avatar.jpg')
class Meta:
# adding extra permissions (default are: add_user, change_user, delete_user)
permissions = (
("access_user_list", "Can access user list"),
("access_user", "Can access user"),
)
ordering = ["-is_staff", "first_name"]
Instead of creating roles on the user, Django already has groups, so you should use them.
The groups follow the same logic:
from django.contrib.auth.models import Group as Auth_Group
from django.db import models
class Group(Auth_Group):
observations = models.CharField(max_length=2048, null=True, blank=True)
def get_users_in_group(self):
return self.user_set.filter(is_active=1).order_by('first_name', 'last_name')
def count_users_in_group(self):
return self.user_set.count()
def __unicode__(self):
return self.name
class Meta:
permissions = (
("access_group_list", "Can access group list"),
("access_group", "Can access group"),
)
ordering = ["name"]
You can clear / add users to a group:
user.groups.clear()
user.groups.add(group)
Clear / add permissions to the group:
group.permissions.clear()
group.permissions.add(permission)
There is also a decorator to check if a user has permissions
from django.contrib.auth.decorators import permission_required
#permission_required(("users.change_user","users.access_user",))
def your_view(request):
...
I've tried many things in the past, but I guess this is the way to go.
If you really need roles, and a user can have more than one role, mayb the best thing would be to create a model Role and add that to the user has a ManyToMany Field
roles = ManyToManyField(Role)
but you could do that with groups