Django add two fields to user profile - python

I am trying to add two additional profile fields and have the native authentication work like normal.
I am trying to fallow the documentation here
and the SO here
In my settings file
#settings.py
AUTH_USER_MODEL = 'users.User'
in my users.user model
#users/models.py
from django.contrib.auth.models import AbstractUser
from django.db import models
class User(AbstractUser):
foo = models.CharField(max_length=32, default='Blue')
bar = models.CharField(max_length=32, default='Blue')
print "user.user"
i have created 3 superusers non can log into admin. i have tried syncing the DB after adding a user. i have tried restating the dev server between adding a user.
the only time i see the output of print "user.user" is when i run the createsuperuser command.
i think i cant log in because the user is not really being created. it runs my User class and then skips actually creating the user. but i am kinda new to this so i could be way off and way out of my league.
why cant i log in and how do i add the two fields?

Have you read the warning in Django's documentation?
Changing AUTH_USER_MODEL has a big effect on your database structure. It changes the tables that are available, and it will affect the construction of foreign keys and many-to-many relationships. If you intend to set AUTH_USER_MODEL, you should set it before running manage.py syncdb for the first time.
If you have an existing project and you want to migrate to using a custom User model, you may need to look into using a migration tool like South to ease the transition.
Given this warning, are you working on a fresh database, or are you migrating using South? If you have an existing database and made these changes, then simply running syncdb will most likely no be sufficient.
If this is a development server without any important data, I would recreate your database, and then run ./manage.py syncdb. If you are using a SQLite database, then you can simply copy it to somewhere else (if you would like to keep the data), and run syncdb again to create a new database.
Here is the relevant documentation.
It would also be helpful to know exactly what error you are receiving. Do you attempt to login and admin tells you that your user/pass combination is not correct, or is there an actual error thrown? Your question doesn't quite make this clear.

Related

Django error when trying to migrate models with foreignkeys that don't have null=True or default set

I have this model that is a post like on Twitter, that has a creator. I'd ideally like the post to always require a creator_id and if the creator gets deleted then delete the post as well
class Post(AbstractBaseModel):
creator_id = models.ForeignKey(User, on_delete=models.CASCADE, related_name="post_creator_id")
body = models.CharField(max_length=511)
Whenever I try to run 'python manage.py migrate' I get this error
"You are trying to change the nullable field 'creator_id' on cheerpost to non-nullable without a default; we can't do that (the database needs something to populate existing rows)."
The options to solve this are are 1) provide a one off default or 2) ignore for now. Neither of these seem to fulfill my constraint that I want to enforce, which is creator_id must exist and is the person who created the post or the entity gets deleted.
I've tried deleting the DB and recreating it from scratch in postgres as well as deleting it using the following query:
TRUNCATE Post;
DELETE FROM Post;
If you've deleted the DB, just the data and tables from DB are deleted.
That doesn't reflect any changes in Django. All the changes you've made to the fields of your model still exist in migrations. You have to delete the old migrations too.
Delete those old migrations from your app, create new migrations from scratch and apply them.
python manage.py makemigrations
python manage.py migrate
Django is asking you to provide a one-off default for any rows you already have in your database, since the field was nullable before the migration. The issue is that Django doesn’t know if there are any rows in the existing database where that column is null, so it needs instructions on what to do if it finds any. You can just provide one and forget about it—it will never be used again after the migration is complete.
Also, you may want to review how the related_name parameter works; you’ve got it backwards.

How to move models in other section in django admin tool?

How to move models to another section in the Django admin site?
In my application module models.py, I have models that are displaying in admin tool in section called "Backend". I want them to display in another section under the name "Requests".
I tried the following
class TransportationRequest(models.Model):
...
class Meta:
app_label = _('Requests')
db_table = 'backend_transportationrequest'
It is works, but now I have issues with South as it is creating migrations to delete all of these models.
Your current issue is that you are trying to change the app_label and db_table, which ends up changing the location of the model data within the database. By default, the database table is generated as [app_label]_[model_name] (backend_transportationrequest in your case), so when you modify both of these, South detects that the model has been removed and created again, even if this isn't actually the case.
The Django migrations framework introduced in 1.7 should have fixed this, so it detects that the model was moved (instead of deleted and created). You may need to fake a migration along the same lines as this with south, which can be done by modifying the two mgirations it generates to not actually delete and create the tables, but rename them.
Django does not currently allow you to easily do this, as the admin site expects that each application that is registered has a unique app_label. You may have luck playing with the label property of your AppConfig, but this is specifically not recommended and has been historically known to cause massive headaches.
One possibility may be to create a clone of your previous model, and only use it to register the app with the Django admin. You would need to create a proxy model with the custom app_label and db_table. If this didn't work (though it should), the other option would be to clone the model as a unmanaged model using the app_label and db_table.

Get rid of get_profile() in a migration to Django 1.6

With Django 1.5 and the introduction of custom user models the AUTH_PROFILE_MODULE became deprecated. In my existing Django application I use the User model and I also have a Profile model with a foreign key to the User and store other stuff about the user in the profile. Currently using AUTH_PROFILE_MODULE and this is set to 'app.profile'.
So obviously, my code tends to do lots of user.get_profile() and this now needs to go away.
Now, I could create a new custom user model (by just having my profile model extend User) but then in all other places where I currently have a foreign key to a user will need to be changed also... so this would be a large migration in my live service.
Is there any way - and with no model migration - and only by creating/overriding the get_profile() function with something like my_user.userprofile_set.all()[0]) somewhere?
Anyone out there that has gone down this path and can share ideas or experiences?
If I where to do this service again now - would obviously not go this way but with a semi-large live production system I am open for short-cuts :-)
Using a profile model with a relation to the built-in User is still a totally legitimate construct for storing additional user information (and recommended in many cases). The AUTH_PROFILE_MODULE and get_profile() stuff that is now deprecated just ended up being unnecessary, given that built-in Django 1-to-1 syntax works cleanly and elegantly here.
The transition from the old usage is actually easy if you're already using a OneToOneField to User on your profile model, which is how the profile module was recommended to be set up before get_profile was deprecated.
class UserProfile(models.Model):
user = OneToOneField(User, related_name="profile")
# add profile fields here, e.g.,
nickname = CharField(...)
# usage: no get_profile() needed. Just standard 1-to-1 reverse syntax!
nickname = request.user.profile.nickname
See here if you're not familiar with the syntactic magic for OneToOneField's that makes this possible. It ends up being a simple search and replace of get_profile() for profile or whatever your related_name is (auto related name in the above case would be user_profile). Standard django reverse 1-1 syntax is actually nicer than get_profile()!
Change a ForeignKey to a OneToOneField
However, I realize this doesn't answer your question entirely. You indicate that you used a ForeignKey to User in your profile module rather than a OneToOne, which is fine, but the syntax isn't as simple if you leave it as a ForeignKey, as you note in your follow up comment.
Assuming you were using your ForeignKey in practice as an unique foreign key (essentially a 1-to-1), given that in the DB a OneToOneField is just a ForeignKey field with a unique=True constraint, you should be able to change the ForeignKey field to a OneToOneField in your code without actually having to make a significant database migration or incurring any data loss.
Dealing with South migration
If you're using South for migrations, the code change from the previous section may confuse South into deleting the old field and creating a new one if you do a schemamigration --auto, so you may need to manually edit the migration to do things right. One approach would be to create the schemamigration and then blank out the forwards and backwards methods so it doesn't actually try to do anything, but so it still freezes the model properly as a OneToOneField going forward. Then, if you want to do things perfectly, you should add the unique constraint to the corresponding database foreign key column as well. You can either do this manually with SQL, or via South (by either editing the migration methods manually, or by setting unique=True on the ForeignKey and creating a first South migration before you switch it to a OneToOneField and do a second migration and blank out the forwards/backwards methods).

Django many to many relationship with built in "User" model

Scenario
I have a basic Django app in which users (django's authentication built in model) and reports have a many-to-many relationship.
The Problem
Django does not create a corresponding table to handle this relationship. My application is called reports. There is an error in the admin system upon trying to create a report and assign users to it. It tries to query the table reports_report_users and it fails as it does not exist.
models.py code
from django.db import models
from django.contrib.auth.models import User
class Report(models.Model):
name = models.CharField(max_length=30, blank=False)
users = models.ManyToManyField(User, related_name='reports')
def __unicode__(self):
return self.name
Attempted Solutions
Used this link as a reference: https://docs.djangoproject.com/en/1.4/topics/db/examples/many_to_many/
Ran manage.py syncdb about 300 times - ok, only once, but there were no errors and upon inspecting the SQLite db there were no additional tables created :(
It seems like you've added to the Report model after the first sync. Thus you're dealing with a migration, which django doesn't do natively.
First, Inspect the sql output, make sure that the create table instruction for your many to many relationship is there.
python manage.py sqlall
Assuming the problem is that this is a migration, which django doesn't handle natively, you've got three options:
1) Delete all db tables for this app, then run syncdb again.
2) Manually create the tables (fairly easy to copy paste the create sql from the sqlall command)
3) Start using a migration framework like South.
In the long run you'll appreciate the investment in learning south. In the short term, deleting the DB file is the fastest.-
Have you deleted your db file and run manage.py syncdb again?

Do I need to create a separate class in my models.py when using the django.contrib.auth.models import user?

The import statement import the needed parts. but is the "user" class already made when you put that into your installed apps? or do you still need to clarify in models.py in order to make the table in the db? or can someone expand on how to use django users and sessions? I'm looking over the django docs right now and they all just go over how to use the thing once. they never put the code in a syntax where users are going to be the ones using the code through a browser and not you through a python shell.
All installed apps can contribute to the database schema. django.contrib.auth.models contributes, among others, the auth_user table behind the django.contrib.auth.models.User model, therefore you do not have to worry about recreating it unless you have a specific reason to do so.
There's a number of things going on here. As you're aware, Django comes with a number of "contrib" packages that can be used in your app. You "activate" these by putting them into your INSTALLED_APPS.
When you run python manage.py syncdb, Django parse the models.py files of every app in INSTALLED_APPS and creates the associated tables in your database. So, once you have added django.contrib.auth to your INSTALLED_APPS and ran syncdb, the tables for User and Group are there and ready to be used.
Now, if you want to use these models in your other apps, you can import them, as you mention, with something like from django.contrib.auth.models import User. You can then do something like create a ForeignKey, OneToOneField or ManyToManyField on one of your models to the User model. When you do this, no tables are created (with the exception of ManyToManyField; more on that in a bit). The same table is always used for User, just as for any of your own models that you might create relationships between.
ManyToManyFields are slightly different in that an intermediary table is created (often called a "join table") that links both sides of the relationship together. However, this is purely for the purposes of that one particular relationship -- nothing about the actual User table is different or changed in any way.
The point is that one table is created for User and this same table is used to store all Users no matter what context they were created in. You can import User into any and all of your apps, create as many and as varied relationships as you like and nothing really changes as far as User is concerned.
If the table name or something else does not fit in your needs you can always just extend the User model.
from django.contrib.auth.models import User
class Employee(User):
...
Any class extending Model class in models.py contributes to database schema. That means, django search your (and also django core) model.py files and looks for any class that extends Model like:
some models.py
class SomeModel(Model):
...
...
class Otherthing(Model):
...
that is also applies for django core code files. Since all Database tables named using application label and model name, database ables created by django also have that...
For example,
from django.contrib.auth.models import User
If you track file hierarchy django -> contrib -> auth and open models.py file, you will see related model. Ther are also other Model classes in here, like Permission and Group models.
Since these models are under auth application, database tables are auth_user, auth_perission and auth_group
When you run manage.py syncdb command for the first time, django will create these tables...

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