Django Model object creation method - django

Question

I'm having two models where UserGroup model, which contains a group admin, and DetailedUser model which related to the group model, where the field user points all users in the certain UserGroup, I want to add a field that when a new user added to the group it store its date and time of user added to the particular group.
class UserGroup(models.Model):
group_admin = models.ForeignKey(User, on_delete=models.CASCADE, related_name='group_by')
group_name = models.CharField(max_length=100)
group_amount = models.PositiveSmallIntegerField()
def __str__(self):
return self.group_name
class DetailedUser(models.Model):
group = models.ForeignKey(UserGroup, on_delete=models.CASCADE, related_name='user_group')
user = models.ManyToManyField(
User, related_name='single_user')
user_added = models.DateTimeField(auto_now_add=True)
is_active = models.BooleanField(default=True)
def __str__(self):
return f"{self.group.group_name}"
How can I done this method?

Answer 1

I think your model design is not correct. What you need(I think) is ManyToManyField with though. For example:
class UserGroup(models.Model):
group_admin = models.ForeignKey(User, on_delete=models.CASCADE, related_name='group_by')
group_name = models.CharField(max_length=100)
group_amount = models.PositiveSmallIntegerField()
members = models.ManyToManyField(User, through="DetailedUser")
def __str__(self):
return self.group_name
class DetailedUser(models.Model):
group = models.ForeignKey(UserGroup, on_delete=models.CASCADE, related_name='user_group')
user = models.ForeignKey(
User, related_name='single_user')
user_added = models.DateTimeField(auto_now_add=True)
is_active = models.BooleanField(default=True)
def __str__(self):
return f"{self.group.group_name}"
Usage example:
>> group = UserGroup.objects.get(pk=1)
>> user = User.objects.first()
>> DetailedUser.objects.create(group=group, user=user)
>> group.memebers.all()