What are the best practices for using validators in Django?

What are the best practices for using validators in Django?

When using validators in Django, it's important to keep them reusable, maintainable, and clear. You should also consider using built-in validators whenever possible.

Can you give me an example of a custom validator?

Sure! Here's a simple custom validator that checks if a value is a positive integer:

from django.core.exceptions import ValidationError

def validate_positive(value):
    if value <= 0:
        raise ValidationError('Value must be a positive integer.')

How do I apply this validator to a model field?

You can apply the custom validator to a model field like this:

from django.db import models

class MyModel(models.Model):
    positive_number = models.IntegerField(validators=[validate_positive])

Are there any performance considerations I should be aware of?

Yes, avoid complex validations that can slow down your application. Keep validations simple and efficient, especially for fields that are frequently accessed.