saving a django orm model with a foreign key - python

I am trying to figure out the best way to save a model that I've got using the django orm. I have a model/table, User. Additionally, I have a model/table called ContactInfo, where we store a foreign key to the User table.
I understand that common django orm practice would be to put the foreign key for the ContactInfo model into the User model, but at this point, we do not want to add anything to the already monolithic user table, so we put the foreign key into the ContactInfo model.
I understand that I can store the User model in the ContactInfo model, call save on ContactInfo, and it should save the User model, but what if I have a one-to-many relationship with users and their contact info? I would rather not have multiple instances of the user table within (1-many) instances of the contact info model/object.
If I can clear anything up, please let me know. At the current moment, the best idea I have is to store an instance of the ContactInfo list as user.contact_info, and override the save method for user user.save() to check for contact_info, and if it exists insert the user.id into each model and save. Unfortunately I just feel like this is a bit messy, but being new-er to django and python, I'm not sure what my options are.
Any help would be greatly appreciated, thanks!

I am not sure if I understand your question correctly. Django provides well support for 1-N relationship. If ContactInfo has a foreign key of User, by default, it's a 1-N mapping.
ContactInfo ---------> User
N 1
So, there is only one User record in your database, looks like this
Table User Table ContactInfo
---------------------------------------------
id user_name id user_id
1 someone 1 1
2 1
3 1
And you don't need to override save method. When you need to add a Contact,
contact = ContactInfo(user=target_user)
# other stuff
contact.save()
#or
target_user.contactinfo_set.create(...)#contactinfo_set is the related name of target_user
#Django maintains the foreign key things.
If you use methods above to insert a new ContactInfo record, then you do not need to iterate your contact_info list to insert user.id into the database.

I am not sure if you're meaning a custom User model or the standard model that ships with Django. If the latter, then Django provides a standard way of storing additional information, called user profiles, associated with each user. See this section in the documentation for details.

Related

How can I relate some, but not all, models to users using Django?

I have a project which includes two different apps: users and school. In my current implementation, the users app contains a custom user class derived from Djagno's AbstractUser. It defines allowed user types as student or teacher, and the user must select one during registration. The school app contains a classroom model which I need to relate to students and one or more teachers.
I have two main problems here. The first is regarding how to relate the classroom model to only specific users restricting their access based on their user type. I have tried using a ManyToManyField relation in the classroom model in order to associate the instance with the user who created it (and then I would later allow the user to add students). It appears I don't understand this field correctly -- it actually all users to all classroom instances. This obviously does not meet my requirement to restrict access among different classroom instances.
OneToOneField and ForeignKey do not seem to meet my needs either. I have tried adding those fields to my user, but then I am restricted to a single classroom per user which is not acceptable either.
I have also played around with creating groups named something like "Classroom_A_teachers" and "Classroom_A_students" and then assigning permissions to them. This approach seems more complicated than necessary.
Am I overlooking something here? This is my first Django project, and I could easily have missed something basic.
Problem two is regarding adding a teacher and student model. I would like to allow a user who is registered as a teacher to be able to create a classroom instance and then to populate that classroom with student instances. Students could optionally create an account too. They would receive a classroom ID from their teacher, enter it, and their account would then be linked to the classroom instance. How can I then associate this user with an existing student model? I have toyed around with this concept with no success.
Any insight is greatly appreciated!
It appears I don't understand this field correctly -- it actually all users to all classroom instances.
It shouldn’t do that. It can just look that way in the Django Admin. The only ones actually in the ManyToMany field are the ones which are highlighted/greyed.
ManyToMany is appropriate for your use case.

User roles schema on Django

A great greetings community
My question is related with the kind of manage users and the schema users in Django, In beginning I ask to you apologize just in case that my questions can will be too "newbies" or without sense, I am starting to related me with the Django Users schemas and their different possibilities of work in the projects.
I have the following situation.
I am building an application in which I will have three differents user types:
Medical
Patient
Physiotherapist
I am using the default Django authentication scheme (django.contrib.auth).
Initially, I did think in this scheme of entities in which the User table is the auth_user table in where Django save the users created:
I have the is_patient, is_medical and is_physiotherapist fields like boolean attributes in the User table.
Like a particular detail I understand that in the Django default model User is not possible modify or add attributes or fields.
This is an important and powerful reason to I cannot add the is_patient, is_medical and is_physiotherapist boolean fields in User table.
A classic recommendation is extend the User model with a Userprofile table in which I add fields or attributes to User Model through of OneToOne relationship. A basic sample is such as follow:
Is of this way that I get that my users in Django can have the field photo and upload one in a given moment ...
Taking advantage of the previous,
The following schema can be suited or can be an alternative for manage user roles (patient, medical and physiotherapist user types) ?
I will have relationships between:
User medical and user patients
user physiotherapist and user patients
and so between them and other tables ...
With this approach these relationships don't will be affected?
The different users will be saved between the Users and UserProfile table.
Is this a good practice in the scalability sense? My tables could be crash or my database?
In addition, I also have seen other alternatives such as:
Role Table/Model
I will have a role table/model independent or separate and that this can be related with the Django User model (One User can will have many roles by example)
This approach can be useful when I want store exclusive information about of a role in specia?
Django Permissions and Authorization
I ignore or unknown the granularity grade that let will me work. Of a single way I have been see that the permissions and authorizations system let will me work with create and edit and remove operations ....
Here, can I see the groups creation?
For example a medical group and allocate them permissions and linked this permissions to the users that compose the group ? Is this another good alternative?
This option seem more single although I don't know if an user could make some operations according to the group privileges that have ... I don't know if this thinking is correct/right
AUTH_USER_MODEL Creating a Custom User model
My requirements for patient, medical and physiotherapist users, require build a custom user model?
In this situation, especially if you want to store different infos for Patients, Medics and Physiotherapists you can create a Model for each and have a OneToOne field for each to the User model.
class Medic(models.Model):
user = models.OneToOneField(User, primary_key=True)
# other fields
class Physio(models.Model):
user = models.OneToOneField(User, primary_key=True)
# other fields
class Patient(models.Model):
user = models.OneToOneField(User, primary_key=True)
# other fields
This way you can give different permissions/roles implicitly in your application logic for each type of user (and still use the groups and permissions that Django offers if you need them for special cases, eg ChiefMedical...).
You will have to define some methods for your application logic like
def user_is_patient(user):
...
If you follow this path it is a good idea to have good tests to make sure that you don't get unexpected things like a user who is a Medic and a Physio...
Django lets you subclass the user model as well. Under the covers it would do the same thing as the code above, so it is probably better to do it explicitly as shown above (this way it is less probable that you access attributes that don't exist in that object!)
Taking advantage of the previous, The following schema can be suited or can be an alternative for manage user roles (patient, medical and physiotherapist user types) ?
The schema you show isn't great because it makes you store the information for all user types in the same table (and with the same fields). For example, Medics and Physios will have a blood type field type like Patients which will probably not be defined.
The different users will be saved between the Users and UserProfile table. Is this a good practice in the scalability sense? My tables could be crash or my database?
There should be no scalability problems with this solution (as long as you don't have millions new entries writes every day) and you can always optimise the database at a further point. However, you will have to make sure that your app doesn't accept 'forbidden' entries (e.g. users with no Medic, Physio or Patient profile)
Here, can I see the groups creation? For example a medical group and allocate them permissions and linked this permissions to the users that compose the group ? Is this another good alternative? This option seem more single although I don't know if an user could make some operations according to the group privileges that have ... I don't know if this thinking is correct/right
You can (should) use Django's permission system to give permissions to your users. You can use them to give different rights to users of the same type (for example Medics that have more permissions than others... or have groups for chief physios...)
Django lets you assign permissions to a group.
But I don't think groups can replace the custom models for each user, since you want to store information for them. Having custom models and groups would be redundant and make your app harder to maintain.
My requirements for patient, medical and physiotherapist users, require build a custom user model?
This option wouldn't be great (unless it is your only option) because your app won't be reusable and you might have problems with some packages as well.
You can create a custom User model or not, in any case, you could have three separate models for storing pertinent data, depending on whether the user is patient, medical, physiotherapist, or any combination of these.
If your permissions scheme is determined solely by the role (patient, medical, physiotherapist) then you don't need to use Django's permissions system, because you know the role(s) of any user and you can, in the worst scenario, hardcode authorization rules.
I gave a glance at question's comments and I view some issues:
()
I realized that your user model does not match with the original data model since having get_medical_profile, get_patient_profile and get_physiotherapist_profile functions inside user model, with that you are assuming that any user could have multiple profiles at the same time, which isn't reflected neither in your profile models (Medical, Patient and Physiotherapist) using OneToOneField nor in original data model of the question, it's an important thing about abstraction and class-responsibility. The requirement (according the model below) seems to say "one user can have only one profile".
So.. I think this can be solved in a straightforward and clean way, you don't need to involve in overall authentication esquema like groups and permissions or adding additional attributes to user model:
class UserProfile(models.Model):
user = models.OneToOneField(User)
# common fields shared by medical, patient and physiotherapist profiles
class MedicalUser(models.Model):
profile = models.OneToOneField(UserProfile)
# medical fields here
class PatientUser(models.Model):
profile = models.OneToOneField(UserProfile)
# patient fields here
class PhysiotherapistUser(models.Model):
profile = models.ForeignKey(UserProfile)
# patient fields here
As you see, you can have a profile which contains common fields shared by all profiles. and each profile has an specific model.
In addition, you can check if user is medical by this small function below, then if there is no an medical profile associated with profile then it will raise exception and it means it's a profile unspecified:
def is_medical_profile(profile):
try:
profile.medical_user
return True
except:
return False
You can also use it in your templates (as a custom template tag) in this way:
{% if profile | is_medical_profile %}
With this approach you don't need to setup AUTH_USER_MODEL
I hope this improves your solution.
Additional notes:
Just in case you decide to have a custom user model, setup settings.AUTH_USER_MODEL and use it for foreign keys to User.
On a piece of text of awesome book Two scoops of Django says:
From Django 1.5 onwards, the official preferred way to attach
ForeignKey, OneToOneField, or ManyToManyField to User
Therefore, your user profile model would change as follows:
from django.conf import settings
from django.db import models
class UserProfile(models.Model):
user = models.OneToOneField(settings.AUTH_USER_MODEL)
Yes, it looks a bit strange, but that's what the official Django docs advice.
#geoom #Ire #lorenzo-peña I 've created an user through Django admin site and I checked their attributes (is_medical, is_patient, is_physiotherapist) via python shell
In [6]: User.objects.filter(username='agarcial').values('is_medical','is_patient','is_physiotherapist')
Out[6]: [{'is_physiotherapist': True, 'is_patient': True, 'is_medical': True}]
For the moment in my views.py I am doing that an user sign in only when this be one of three user types (medical, patient or physiotherapist)
# Create your views here.
class ProfileView(LoginRequiredMixin, TemplateView):
template_name = 'profile.html'
def get_context_data(self, **kwargs):
self.request.session['Hi'] = True
context = super(ProfileView, self).get_context_data(**kwargs)
is_auth = False
name = None
# Check if in the request goes the user
user = self.request.user
# Check about of possible cases (For now is one profile)
if user.is_medical:
#if self.request.user.is_authenticated():
print (user.is_medical)
is_auth = True
profile=user.get_medical_profile()
#name = self.request.user.username
data = {
'is_auth':is_auth,
'profile':profile,
}
context.update({'userprofile':profile, 'data':data})
elif user.is_patient:
print (user.is_patient)
is_auth=True
profile=user.get_patient_profile()
data = {
'is_auth':is_auth,
'profile':profile,
}
context.update({'userprofile':profile,'data':data})
elif user.is_physiotherapist:
print (user.is_physiotherapist)
is_auth=True
profile=user.get_physiotherapist_profile()
data = {
'is_auth':is_auth,
'profile':profile,
}
context.update({'userprofile':profile,'data':data})
return context
def get_userprofile(self):
return self.request.user.userprofile
If I check the other possible combinations (User patient,medical and physiotherapist) this could work?
I think create groups for (Medicals, Patients, Physiotherapists) and binding users for the authorization topic, although I should review other things for authorization process such as django guardian for example?
How about this?

Django best user model design

Probably some of you would tell that is a recurrent topic, but after reading many articles, it still seems very ambiguous to me. My question is about the best way to use and to extend the User model preserving the authentication (and others) mechanisms available in Django. However, I prefer to describe my design:
There are users (Patients) that can sign up providing basic info (first name, last name, birth date, gender, email, password). Preferably, email should replace the username.
When a Patient is in the application, it can register a new Patient (imagine a member of the family), but email and password are not required because they won't log into the system.
For the first part, Django doc propose to extend User with a OneToOne relation to a Profile. However, to replace username by email they propose then to create a custom User extending from an AbstractUser, as well as an associated UserManager. The second requirement is like doing a one-to-many relation from users to users. So, according to Django, which should be the best strategy: creating a completely new user model and the one-to-many user-user adding an specific attribute that distinguish between main users and family members? OR extending Django User with a Profile and then a one-to-many relation profile-profile? Which option preserves the best the benefits of Django user authentication and model administration?
Thank you for any comment, suggestion, example.
First, if you want to use email as username, use the Django custom user functionnality. It works well.
Then, note that it's not because you created your own User that you can't extend it with a Profile.
So, a good solution could be :
Create a Django custom User without trying to add specific fields to it (the one and only purpose here is to use email to log instead of username).
Create a PatientProfile class that have a one-to-one relatioship (blank=True) with User class.
This way, a patient that can log in will be related to a User instance and will use this instance for this purpose. On the other hand, the patient who can't log in won't be related to any User instance.
In the end, there's no problem to use OneToMany relationship with PatientProfile for what's you want to do.

get user profile in django

hello i'm new in python and django
I need a view that get current user profile I know I shoud use get_profile from User but I don't know how to use it . i read the django document and It didn't help me.
this is what I found from doc:
from django.contrib.auth.models import User
profile=request.user.get_profile()
Django's documentation says it all, specifically the part Storing additional information about users. First you need to define a model somewhere in your models.py with fields for the additional information of the user:
models.py
from django.contrib.auth.models import User
class UserProfile(models.Model):
# This field is required.
user = models.OneToOneField(User)
# Other fields here
accepted_eula = models.BooleanField()
favorite_animal = models.CharField(max_length=20, default="Dragons.")
Then, you need to indicate that this model (UserProfile) is the user profile by setting AUTH_PROFILE_MODULE inside your settings.py:
settings.py
...
AUTH_PROFILE_MODULE = 'accounts.UserProfile'
...
You need to replace accounts with the name of your app. Finally, you want to create a profile every time a User instance is created by registering a post_save handler, this way every time you create a user Django will create his profile too:
models.py
from django.contrib.auth.models import User
class UserProfile(models.Model):
# This field is required.
user = models.OneToOneField(User)
# Other fields here
accepted_eula = models.BooleanField()
favorite_animal = models.CharField(max_length=20, default="Dragons.")
def create_user_profile(sender, instance, created, **kwargs):
if created:
UserProfile.objects.create(user=instance)
post_save.connect(create_user_profile, sender=User)
Accessing the Profile
To access the current user's profile in your view, just use the User instance provided by the request, and call get_profile on it:
def your_view(request):
profile = request.user.get_profile()
...
# Your code
Basically django User models will provide access only for the fields ( firstname,lastname,email,password,is_staff,is_active,last_login).
However if we want to add any extra fields to this model, say we need to add a new column named dateofbirth for every user, then we need to add a column named DOB into User model. But this is not possible as we aren't able to edit django User models.
To achieve this either
1.We can have a separate new table with email id & DOB column, such that a column in User model is mapped with a column in the new table. But this will create a new db instance for every db request. Say if u want to find the DOB of a customer,
First we need to fetch the value of mapped id of a customer from the
User table.
WIth the above value, get DOB from the new table.
In the second method,
Instead of using django User model, use your own customize model with all the fields needed. However if any updation related to security or some enhancement made to django User model we can't use it directly. We need to do more code changes at our end( wherever we use our customize models.) This will be a bit pain for a developer to identify the code & make changes.
To overcome the above issues, django introduce django profile which is very simple and more flexible. The advantages are
Updation/enhancement to the User model can be applied without modifying the code much
No need of creating new db instance to fetch the extra values.
Since the field has onetoone mapping deletion of data from one table will delete others also.
More secure, since we use django models ( no sql injection)
How to Use this:
In settings.py create a variable AUTH_PROFILE_MODULE = "appname.profiletable"
In models.py, create a new table with the fields needed and make sure that the id in User model is onetoone mapped with new table.
create a signal which inserts a row into the new table whenever a new entry is added into User model.
The value in the new table can be accessed using User object itself.
Say, we created a new table extrauser which has DOB, emailid. To find the DOB of a customer, use
a=User.objects.get(email='x#x.xom')
a.get_profile().DOB will give the dateofbirth value from extrauser table.
Hope the above details make you clear in understanding django profile. Incase of any help further, let me know. I have used django profile in my project.
Old question but I thought anyone seeing it today may benefit from this:
Django 1.5 adds the ability to - easily - extend the User model. This may be preferable as you now only got one object to deal with rather than two! Seems the more modern way.
https://hurricanelabs.com/blog/django-user-models/
You need to specify which class is your "Profile" by setting AUTH_PROFILE_MODULE = 'accounts.UserProfile' (for example)
https://docs.djangoproject.com/en/1.4/topics/auth/

How the datas are connected to the specific user ID?

I'm new to Django and python. I've done login forms but I need to know. How can I connect the contents of the page with the user.
For example: It's a Q&A site. When you logged in, It shows profile page with the questions that user asked before. How the datas are linked to the specific user ID in the model?
Can it be done using the User object? If so, could you give me some simple example with the script?
Thank you.
Anything that "belongs" to a user, should either have a ForeignKey or ManyToManyField (depending on whether the object is owned by one user or many) to User on it. Then you can either filter the model based on the User:
SomeModel.objects.filter(user=some_user)
# where `user` is the name of your foreign key field
Or you can access the model through the user via reverse relations, for example:
class SomeModel(models.Model):
...
user = models.ForeignKey(User)
# Later ...
some_user.somemodel_set.all()
The second method is more typical since you generally have the user already from the request, so in your view, you'd just do:
somemodels = request.user.somemodel_set.all()
To get all the SomeModels that belong to the currently logged-in user.

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