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Django: How do I get referenced objects in a symmetric ManyToMany relationship?

I've created a Many-to-Many relationship for the model UserProfile, to enable users to grant access to a particular feature to one another. The relationship works as expected with the use of symmetrical=False to ensure a user access is one-way.
Model
from django.contrib.auth.models import User
class UserProfile(models.Model):
user = models.OneToOneField(User, on_delete=models.CASCADE)
phone = models.IntegerField(blank=True, null=True)
image = models.ImageField(upload_to='profile_image', default="default_thumbnail.jpg")
department = models.ForeignKey(DepartmentModel, on_delete=models.SET_NULL, null=True)
allow_booking_access = models.ManyToManyField("self", blank=True, symmetrical=False)
def __str__(self):
return self.user.username
class UserInline(admin.StackedInline):
model = UserProfile
can_delete = False
verbose_name_plural = 'UserAccounts'
class UserAccount(BaseUserAdmin):
inlines = (UserInline,)
I am able to query the users that a particular user wants to grant access to via: (for example id=1)
UserProfile.objects.get(id=1).allow_booking_access.all()
However, I would like to retrieve the users that have granted access to the particular user.
How would I do this?
Additional Information
Using Relation
Database Information

You can filter with:
UserProfile.objects.filter(allow_booking_access=my_user)
With your sample data, it will return the UserProfile with id=7 for this query.
or if you want to query in reverse:
UserProfile.objects.filter(userprofile=my_user)
With your sample data, it will return the UserProfiles with id=7, id=3, user=4 and user=7 for this query.

Django: Filter records based on one to many relationship

I have following models,
class User(models.Model):
name = models.CharField(max_length=255)
...
class InsuranceProfile(models.Model):
user = models.ForeignKey(User, on_delete=models.CASCADE)
...
class ProductExpertiseMaster(models.Model):
class Meta:
db_table = 'product_expertise_master'
name = models.CharField(max_length=255)
main_category = models.CharField(max_length=255)
class UserProductExpertise(models.Model):
user = models.ForeignKey(User, on_delete=models.DO_NOTHING)
product_expertise = models.ForeignKey(ProductExpertiseMaster, on_delete=models.DO_NOTHING)
So what I am trying to do is I want to filter records based on various fields some of the belong to User model & some of them belong to the InsuranceProfile model.I am filter the records based on User & InsuranceProfile model which is working fine. Now i want to add one more filter which will be based on the UserProductExpertise model.I want to get all the InsuranceProfiles with User details who have some matching condition with product expertise entries in UserProductExpertise model. Any help would appreciated.

You can try like this using __isnull:
InsuranceProfile.objects.filter(user__userproductexpertise__isnull=False)
It will return all the users who has an entry in in UserProductExpertise model. For querying, you need to use all lowercase of the model name, (ie userproductexpertise) and add __isnull at the end of it.

I think you should make some changes in your models before proceeding further.
UserProductExpertise model is the bridge table between ProductExpertiseMaster and User, which provides a many-to-many relationship. If you won't add additional fields to UserProductExpertise model, you can drop it and define user relation in ProductExpertiseMaster model.
If you prefer using seperate model for this relationship, on_delete=models.DO_NOTHING is prone to errors, you can change it to models.CASCADE
Here is an example with many-to-many relation:
class User(models.Model):
name = models.CharField(max_length=255)
class InsuranceProfile(models.Model):
user = models.ForeignKey(User, on_delete=models.CASCADE)
content = models.CharField(("Content"), max_length=500)
class ProductExpertiseMaster(models.Model):
class Meta:
db_table = 'product_expertise_master'
name = models.CharField(max_length=255)
main_category = models.CharField(max_length=255)
user = models.ManyToManyField(User, verbose_name=("Users"), related_name="expertises")
For filtering your query:
InsuranceProfile.objects.filter(user__expertises__isnull=False)

Django admin - Inline with choices from database

I need some basic help with the django admin site. What I basically want to do is to be able to populate an inline with choices from the database. For example consider the following models:
class Item(models.Model):
description = models.CharField(max_length=100)
class Category(models.Model):
name = models.CharField(max_length=100)
item = models.ForeignKey(Item, on_delete=models.CASCADE, null=True, blank=True)
And in admin.py I have the following setup:
class CategoryAdminForm(forms.ModelForm):
name = forms.ChoiceField(choices = category_service.get_all_categories())
class CategoryInline(admin.TabularInline):
model = Category
form = CategoryAdminForm
class ItemAdmin(admin.ModelAdmin):
inlines = [CategoryInline]
admin.site.register(Item, ItemAdmin)
admin.site.register(Category)
What I want to be able to do is to insert categories into db, and when I want to insert an item, the categories inline to be populated with categories from the db.
With the current setup it is not working. It says that category is not an iterable object. What am I missing here?

You should replace your ChoiceField with a ModelChoiceField. They allow you to specify a queryset to populate the choices.
category = forms.ModelChoiceField(queryset=Category.objects.all(), empty_label="(Nothing)")

django admin. Create parent with child in same form

I have two classes in my model.py
class User(models.Model):
name = models.CharField()
phone = models.CharField()
# Other common fields
class Customer(User):
payment = models.CharField()
user__id = models.OneToOneField('User', db_column='id', primary_key=True)
class Company(User):
address = models.CharField()
user_id = models.OneToOneField('User', db_column='id', primary_key=True)
When I use the admin of Customer/Company it includes all User fields, that is perfect for me. But this form of Customer/Company also includes a dropdown list with the foreign key of an User, and I don't want to create the User first and then the Customer/Company object. I want that when I fill the Customer/Company form (with User fields) I should create the User object too.
Is there a way to solve this without create a User instance prior the Customer/Company instance?
Thanks

You can do this by adding an inline in your model registration in admin.py.
class AInline(admin.TabularInline):
model = A
class BAdmin(admin.ModelAdmin):
inlines = [AInline]
admin.register(A)
admin.register(B, BAdmin)
Django inline model admin documentation

Django forms with Foreign keys

I have scenario in which a user can have multiple books. I can create two different models for user and books and relate them using foreign keys (or one-to-many will be right way ?).
I have created a django forms for User model but when i do like this {{form.as_p}} in templates only user model fields is shown not books field.
I want that with user fields my books model filed also displayed (like book names field more then once because he can have multiple books) , Please let me know if it is possible using django forms/models or I have to user simple html forms with jquery and then save data in models.
Thanks
EDIT:
my models :
class Product(models.Model):
categories = models.CharField(max_length=5, choices = settings.CATEGORIES)
name = models.CharField(max_length=100)
description = models.TextField()
currency = models.CharField(max_length=5, choices = settings.CURRENCY)
status = models.BooleanField(default=True)
def __unicode__(self):
return self.name
class Prices(models.Model):
products = models.ForeignKey(Product)
prices = models.IntegerField()
def __unicode__(self):
return self.id

if you are creating a form for Prices, try putting this in your model form:
products = forms.ModelMultipleChoiceField(queryset=Product.objects.all())

I think you should add required fields in meta class such as
class ThreadForm(ModelForm):
class Meta:
model = Thread
fields = ('Books', 'User')
Please understand the work flow to use foreign keys in model form here.