How to create a unique slug in Django

Question

I am trying to create a unique slug in Django so that I can access a post via a url like this: http://www.example.com/buy-a-new-bike_Boston-MA-02111_2

The relevant m

Answer 1

Here are a couple functions that I use. You pass in the model instance and the desired title into unique_slugify which will add the slug if it doesn't exist, otherwise it will continue trying to append a 4 digit random string until it finds a unique one.

import string
from django.utils.crypto import get_random_string

def unique_slugify(instance, slug):
    model = instance.__class__
    unique_slug = slug
    while model.objects.filter(slug=unique_slug).exists():
        unique_slug = slug + get_random_string(length=4)
    return unique_slug

I usually use it by overriding the model save method.

class YourModel(models.Model):
    slug = models.SlugField()
    title = models.CharField()

    def save(self, *args, **kwargs):
        if not self.slug:
            self.slug = unique_slugify(self, slugify(self.title))
        super().save(*args, **kwargs)

Answer 2

If you are thinking of using an app to do it for you, here is one.

https://github.com/un33k/django-uuslug

UUSlug = (``U``nique + ``U``code Slug)


Unicode Test Example
=====================
from uuslug import uuslug as slugify

s = "This is a test ---"
r = slugify(s)
self.assertEquals(r, "this-is-a-test")

s = 'C\'est déjà l\'été.'
r = slugify(s)
self.assertEquals(r, "c-est-deja-l-ete")

s = 'Nín hǎo. Wǒ shì zhōng guó rén'
r = slugify(s)
self.assertEquals(r, "nin-hao-wo-shi-zhong-guo-ren")

s = '影師嗎'
r = slugify(s)
self.assertEquals(r, "ying-shi-ma")


Uniqueness Test Example
=======================
Override your objects save method with something like this (models.py)

from django.db import models
from uuslug import uuslug as slugify

class CoolSlug(models.Model):
    name = models.CharField(max_length=100)
    slug = models.CharField(max_length=200)

    def __unicode__(self):
        return self.name

    def save(self, *args, **kwargs):
        self.slug = slugify(self.name, instance=self)
        super(CoolSlug, self).save(*args, **kwargs)

Test:
=====

name = "john"
c = CoolSlug.objects.create(name=name)
c.save()
self.assertEquals(c.slug, name) # slug = "john"

c1 = CoolSlug.objects.create(name=name)
c1.save()
self.assertEquals(c1.slug, name+"-1") # slug = "john-1"

Answer 3

from django.utils.text import slugify Helps a lot and has quite clear Concepts. Here one example on How to auto-generate slug by using from django.utils.text import slugify

utils.py

from django.utils.text import slugify
import random
import string

# Random string generator
def random_string_generator(size=10, chars=string.ascii_lowercase + string.digits):
    return ''.join(random.choice(chars) for _ in range(size))

# Unique Slug Generator 
def unique_slug_generator(instance, new_slug=None):
    """
    It assumes your instance has a model with a slug field and a title character (char) field.
    """
    if new_slug is not None:
        slug = new_slug  
    else:
        slug = slugify(instance.title)  

    Klass = instance.__class__

    qs_exists = Klass.objects.filter(slug=slug).exists()

    if qs_exists:
        new_slug = "{slug}-{randstr}".format(slug=slug, randstr=random_string_generator(size=4))
        return unique_slug_generator(instance, new_slug=new_slug)
    return slug

models.py

from django.db.models.signals import pre_save # Signals
# import the unique_slug_generator from .utils.py 
from .utils import unique_slug_generator

class Product(models.Model):
    title  = models.CharField(max_length=120)
    # set blank to True
    slug  = models.SlugField(blank=True, unique=True)

def product_pre_save_receiver(sender, instance, *args, **kwargs):
    if not instance.slug:
        instance.slug = unique_slug_generator(instance)


pre_save.connect(product_pre_save_receiver, sender=Product)

Django documentation explains Django.utils.text import slugify to generate slug automatically. You can read more detail here

After implementing the code, while creating product, you may leave the slug field blank, which will be further aquired with auto generated slug for the product which will be unique in this case.

Answer 4

This is the simple and small code i am using for generating unique slug, you only need one field to create your unique slug field

from random import randint

def save(self, *args, **kwargs):
    if Post.objects.filter(title=self.title).exists():
        extra = str(randint(1, 10000))
        self.slug = slugify(self.title) + "-" + extra
    else:
        self.slug = slugify(self.title)
    super(Post, self).save(*args, **kwargs)

I hope you like this.

Answer 5

This is a simple implementation that generate the slug from the title, it doesn't depend on other snippets:

from django.template.defaultfilters import slugify

class Article(models.Model):
    ...
    def save(self, **kwargs):
        if not self.slug:
            slug = slugify(self.title)
            while True:
                try:
                    article = Article.objects.get(slug=slug)
                    if article == self:
                        self.slug = slug
                        break
                    else:
                        slug = slug + '-'
                except:
                    self.slug = slug
                    break

        super(Article, self).save()

Answer 6

Try this, worked out for me,welcome in advance:

class Parcel(models.Model):
    title = models.CharField(max_length-255)
    slug = models.SlugField(unique=True, max_length=255)
    weight = models.IntegerField()
    description = models.CharField(max_length=255)
    destination = models.CharField(max_length=255)
    origin = models.CharField(max_length=255)

    def __str__(self):
        return self.description

    def save(self, *args, **kwargs):
        if not self.slug:
            t_slug = slugify(self.title)
            startpoint = 1
            unique_slug = t_slug
            while Parcel.objects.filter(slug=unique_slug).exists():
                unique_slug = '{} {}'.format(t_slug, origin)
                origin += 1
            self.slug = unique_slug
        super().save(*args, **kwargs)