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How to use UUID in Django

UUID(Universal Unique Identifier) is a Python library that generates random objects of 128 bits. It is a standard built-in Python library which means you don’t need to install anything. There are three main algorithms used for generating randoms:

Using IEEE 802 MAC addresses as a source of uniqueness
Using pseudo-random numbers
Using well-known strings combined with cryptographic hashing
The UUID uses getnode() to retrieve the MAC value on a given system:

import uuid
print(uuid.getnode())
251053329979042
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First, let’s look at how we can use UUID in general:

import uuidp
print(uuid.uuid4())
cae6f5a3-377d-4eaa-8d27-3ff12aece93e
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UUID usage in Django
Now, let’s look at using UUID usage in Django.

It is commonly used to replace the Django id field. By default, Django gives each model auto-incrementing primary key field:

id = models.AutoField(primary_key=True)

if you want to explicitly set the primary key you must specify primary_key=True then Django won’t add this field automatically because it detects that you set it manually.

Now let’s look real example. Assume that you have a Subscription Model

class Subscription (models.Model):
name = models.CharField(verbose_name=_("Subcription Name"),
                        help_text=_("Required and unique"),
                        max_length=255,
                        unique=True,
)
cdate = models.DateTimeField(auto_now_add=True)
udate = models.DateTimeField(auto_now=True)
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In general when we access this model’s detail like below:

https://domain.com/subcriptions/1

In the frontend, users can access other’s data by replacing 1 to 2,3,4, etc. We can call it a simple Security leak. For in these cases we can replace the id field with UUID.

class Subscription (models.Model):
id = models.UUIDField(primary_key=True,
                      default=uuid.uuid4,
                      editable=False)
                      name = models.CharField(
                      verbose_name=_("Subcription Name"),
                      help_text=_("Required and unique"),
                      max_length=255,
                      unique=True,
                      )
cdate = models.DateTimeField(auto_now_add=True)
udate = models.DateTimeField(auto_now=True)
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As we showed above UUID generates random and it is not predictable.

Thanks for reading. I hope you enjoyed it ❤.
The post first appeared in my blog
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