How to reuse a Django model for multiple relationships

Question

I want to make a task model and a user model. And I want each task to be able to be related to 3 users. Each task should be related to a creator user, an assignee user, and a verifier user. And I want to only have one user table. My inclination is to have 3 foreign keys on the task table: creator_id, assignee_id, and verifier_id. Is this the correct way to do it? How do I model that in Django?

UPDATE

Here's my simplified models

class User(models.Model):
    id = models.CharField(primary_key=True, max_length=100)
    name = models.CharField(max_length=100)

class Task(models.Model):
    id = models.CharField(primary_key=True, max_length=100)
    title = models.CharField(max_length=100)

    creator = models.ForeignKey('User', on_delete=models.DO_NOTHING, related_name='creator_tasks')
    assignee = models.ForeignKey('User', on_delete=models.DO_NOTHING, related_name='user_tasks')
    verifier = models.ForeignKey('User', on_delete=models.DO_NOTHING, related_name='verifier_tasks')

And here's the error I get when I relate a user to a task as a creator and try to get the task's creator:

$ python manage.py shell
>>> from todoapp.models import User
>>> from todoapp.models import Task
>>> user = User.objects.get(id='1')
>>> task = Task.objects.get(id='1')
>>> task.creator_id = user.id
>>> task.save()
>>> task.creator
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/Users/josh/.venv/myenv/lib/python3.9/site-packages/django/db/models/fields/related_descriptors.py", line 188, in __get__
    raise self.RelatedObjectDoesNotExist(
todoapp.models.Task.creator.RelatedObjectDoesNotExist: Task has no creator.

I'm not getting that error when I try to replicate it. How were your User and Task objects created? — PT-Hrothgar
– PT-Hrothgar, Commented Oct 25 at 22:58

repent · Accepted Answer · 2025-10-26 11:58:31Z

2

Try something like :

task.creator = user
task.save()

...and so on for an assignee and a verifier

This automatically manages the foreign key relationship properly.

edited Oct 26 at 11:58

answered Oct 26 at 11:57

repent

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1 Comment

wetjosh Oct 26 at 16:46

This was the trick. Thank you

santeena · Accepted Answer · 2025-10-25 08:46:09Z

0

Use 3 Foreignkey on Task model and use related_name to identify each of creator, assigner and verifier

answered Oct 25 at 8:46

santeena

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2 Comments

Community Oct 25 at 8:58

As it’s currently written, your answer is unclear. Please edit to add additional details that will help others understand how this addresses the question asked. You can find more information on how to write good answers in the help center.

wetjosh Oct 25 at 17:18

That's exactly what I thought I should do. However, I'm getting an error. It doesn't think a Task has a relation to Creator. I added my code. Do I have it set up right? Also, do the values I'm giving for related_name make sense? Can you suggest better if not? Am I setting creator correctly in my shell session and calling creator correctly?

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