[Django]-How to use UUID

You need to use the class you created as a subclass when declaring your Person model like this:

import uuid
from django.db import models

class MyUUIDModel(models.Model):
  id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)

class Person(MyUUIDModel):
  ...

This way Person becomes a subclass of MyUUIDModel and will inherit its id field definition.

EDIT: Actually I was wrong. It’s not possible yet to implement it as DEFAULT_AUTO_FIELD as it has to inherit from IntegerField. Here’s the ticket in the django project with feature request to make it possible. Once it’s resolved I’ll update my answer.

As of Django 3.2, if you want to use uuid as a pk for all your models on a project-wide level, you don’t need a generic abstract model anymore. Just define DEFAULT_AUTO_FIELD setting

default value

DEFAULT_AUTO_FIELD = 'django.db.models.AutoField'

so something like this should work

DEFAULT_AUTO_FIELD = 'django.db.models.UUIDField'

Or even better, create your own field.

DEFAULT_AUTO_FIELD = 'project.common.models.CustomUUIDField'

Where you also define uuid type etc.

As seen in the docs, it can also be applied on an app level.

class MyAppConfig(AppConfig):
    default_auto_field = 'project.common.models.CustomUUIDField'

You can directly add the id field as a UUIDField in the Person model. There is no need for a separate MyUUIDModel.

I think you have confused it with the MyUUIDModel used in the UUIDField example where the id is a UUIDField. You can just use the below code and it will use UUIDs for id.

import uuid
from django.db import models

class Person(models.Model):
    ...
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False) 

To use UUID in Django for a new model see Django Docs.

However, if you want to use it for the existing model (with unique=True) having data corresponding to it, you will not be able to do it directly by the above documentation. It will create migration errors.
To do it without losing the data follow all the steps carefully of this Django Documentation.

in model import uuid:

import uuid

in class model use:

class Article(TimeStampedModel):
    uuid = models.UUIDField(editable=False, default=uuid.uuid4, unique=True)
    user = models.ForeignKey(User, on_delete=models.SET_NULL, related_name='articles', null=True)
    categories = models.ManyToManyField(ArticleCategory, blank=True)
    title = models.CharField(max_length=500, null=True, blank=True)
    body = RichTextUploadingField(config_name='portal_lobar_config')
    image = models.ImageField(upload_to='article_images/', null=True, blank=True)
    headline = models.BooleanField(default=True)
    tags = models.ManyToManyField(ArticleTag, blank=True)
    slug = AutoSlugField(max_length=500, populate_from='title', unique_with='created__month', null=True)
    published = models.BooleanField(default=False)
    published_at = models.DateTimeField(null=True, blank=True)

    def __str__(self):
        return self.title

    class Meta:
        ordering = ['-created']

You can use the UUIDField in Django to generate unique IDs for each object in your model. The UUIDField is a special field to store universally unique identifiers. It uses Python’s UUID class. UUID, Universal Unique Identifier, is a python library that helps in generating random objects of 128 bits as ids. It provides the uniqueness as it generates ids on the basis of time, Computer hardware (MAC etc.). Universally unique identifiers are a good alternative to AutoField for primary_key. The database will not generate the UUID for you, so it is recommended to use default. Here is an example of how you can use the UUIDField:

import uuid
from django.db import models

class MyUUIDModel(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)

class Person(models.Model):
    ...
    unique_id = models.ForeignKey(MyUUIDModel)

This should work for you. If you still face issues with generating unique IDs every time you create an object, you can try using uuid.uuid1() instead of uuid.uuid4(). The uuid1() function generates a UUID from the host ID, sequence number, and the current time.