Prettier URLs with automatic slug generation 🐌

When building a website, sometimes you want a URL for a specific piece of data, but the URL should be nicer than /products/123. A slug can be used for a prettier URL like /products/really-cool-headphones and, bonus points!, it's better for SEO as well.

`SlugField`

Django has a built-in SlugField designed for this. It seems like the right approach, but you have to manually update the slug unless you always use the built-in admin (in which case you can use prepopulated_fields).

If you want the slug generation to even more automated you will need an external library. Luckily there are two great ones to choose from.

`django-extensions`

The "kitchen sink" package that is django-extensions has AutoSlugField. The populate_from kwarg for AutoSlugField takes in a list of fields or model methods to generate a slug.

from django.db import models
from django_extensions.db.fields import AutoSlugField

class Article(models.Model):
    title = models.CharField(max_length=200)
    author_name = models.CharField(max_length=200)
    slug = AutoSlugField(populate_from=["title", "author_name","get_publish_date"])

    def get_publish_date(self):
        ...

You can also use a custom method to create the slug with the slugify_function kwarg.

`django-autoslug`

django-autoslug is a tiny focused package just for automatically generating slugs.

from django.db import models
from autoslug import AutoSlugField

class Article(models.Model):
    title = models.CharField(max_length=200)
    slug = AutoSlugField(populate_from="title")

It also has some more specialized features which make sure that your slugs are unique across the entire table of data. There are custom methods to create the slug as well.

Have your cake and eat it, too? 🎂

Another approach that sites like StackOverflow use is to have an identifier and the slug in the URL. Look at an example URL closely:

https://stackoverflow.com/questions/34230208/uuid-primary-key-in-postgres-what-insert-performance-impact

The slug at the end isn't used to look up the question at all. You can verify this if you don't believe me by changing the slug and going to the URL again.

/questions/324230208 is the question identifier and is the only part that is used to look up the specific question. Once the question has been found if the uuid-primary-key-in-postgres-what-insert-performance-impact portion of the URL is different than the question's slug in the database, they redirect to a URL with the correct slug. This ensures that if the slug ever changes users will always get to the right URL.

This is one way to have nicer looking URLs, but handle if the slug might change.

Keep a history of all `slugs` forever

Another approach is to keep a list of slugs that are generated as a foreign key (i.e. one-to-many). Inside your view, you would include that table in your query, but redirect to the latest slug if necessary.

def product(request, slug):
    product = Product.objects.get(slugs__slug=slug)

    last_created_slug = product.slugs.all().order_by("-created").first()

    if last_created_slug.slug != slug:
        return redirect("product", slug=last_created_slug.slug)

    ...

Personally, this approach seems like overkill and not worth the hassle.

My recommendation 🌟

Both of the additional libraries are great. Personally, I tend to:

use AutoSlugField from django-extensions if I have already included it in the project and the slugs I need to create are straight-forward
only include django-autoslug if I need the additional functionality it provides

Hi, I'm Adam 👋

I've been a backend programmer for ~20 years in a variety of different languages before I discovered Python 10 years ago and never looked back. alldjango includes all the hard-won experience I've gained over the years building production-scale Django websites.