如何在 Django 中实现经过验证的字段？

Question

In Django I'd like to add a field "verified" of type BooleanField to my models which shall indicate if the current model instance has been reviewed by a staff user member or not. Whenever a model instance field other than the "verified" field changed the verified field value shall be reset to False . Whenever only the "verified" field has been changed it's value shall be taken as is (most of the time True but potentially False as well).

One possibility would be to reset the "verified" field in post-save signals handlers considering update_fields passed to save() . However using signals seems to be considered an anti-pattern in almost all use cases. Instead one should override the save() method. But still when overriding save I'd have to determine update_fields manually somehow. Otherwise I've no information about which fields changed.

How can I implement something like this most easily. I'd prefer a solution using a third-party package wo custom hacks or a solution without any dependencies to other packages. However using django-model-utils monitorfield , django-dirtyfields for a custom implementation or something equivalent would be ok as well.

Answer 1

Using dirty-fields seems to be easiest to implement a verified field. So far I came up with something like follows:

DJANGO-APP/models.py :

from django.db import models
from dirtyfields import DirtyFieldsMixin


class VerifiedModel(DirtyFieldsMixin, models.Model):
    """
    Abstract class which allows to extend models with user verification model field.
    """
    ENABLE_M2M_CHECK = True
    verified = models.BooleanField(
        default=False,
        help_text="The verification status. True means meta-data is verified. False means meta-data is not verified. The verification status is reset to False whenever a field is set.",
    )

    def _update_verified_field(self):
        """
        To be called in inheriting model's save() method.
        """
        if self.is_dirty():
            if not 'verified' in self.get_dirty_fields():
                self.verified = False

    class Meta:
        abstract = True


class ModelToBeVerified(VerifiedModel):

    ...

    def save(self, *args, **kwargs):
        ...
        self._update_verified_field()
        return super(ModelToBeVerified, self).save(*args, **kwargs)