Add a Slugfield & Overwrite Save in Django Model
To add a SlugField and overwrite the save method in a Django model, follow these steps:
- Define the SlugField in the Model: Add a
SlugFieldto your model to store the slug. - Overwrite the Save Method: Customize the
savemethod to automatically generate and assign a slug value before saving the object.
Here’s a step-by-step example:
Step 1: Install Django Extensions (Optional)
If you want to use the slugify function from Django Extensions, install it via pip:
pip install django-extensions
Step 2: Modify Your Model
from django.db import models
from django.utils.text import slugify
class MyModel(models.Model):
name = models.CharField(max_length=255)
slug = models.SlugField(unique=True, blank=True)
def save(self, *args, **kwargs):
if not self.slug:
# Generate a unique slug
self.slug = slugify(self.name)
# Ensure the slug is unique
unique_slug = self.slug
num = 1
while MyModel.objects.filter(slug=unique_slug).exists():
unique_slug = f'{self.slug}-{num}'
num += 1
self.slug = unique_slug
super(MyModel, self).save(*args, **kwargs)
def __str__(self):
return self.name
Explanation:
- SlugField Definition:
slug = models.SlugField(unique=True, blank=True)
unique=Trueensures that each slug is unique.blank=Trueallows the field to be empty in the form (the slug will be generated automatically if not provided).
- Overwriting the Save Method:
- The
savemethod is overridden to generate a slug if it doesn’t exist. slugify(self.name)generates a slug from thenamefield.- A
whileloop ensures the slug is unique by appending a number if a conflict is found. - The
super(MyModel, self).save(*args, **kwargs)call saves the model instance.
- The
Optional: Using Django Extensions (if installed)
If you installed Django Extensions, you can use its slugify function instead of the one from Django’s utilities:
from django_extensions.db.fields import AutoSlugField
class MyModel(models.Model):
name = models.CharField(max_length=255)
slug = AutoSlugField(populate_from='name', unique=True)
def __str__(self):
return self.name
This approach simplifies the slug generation and ensures uniqueness using the AutoSlugField.
With these steps, you can add a SlugField and overwrite the save method in your Django model to automatically generate and ensure unique slugs for your model instances.
