Process a topic name for basic forum app

Using Django
6

Hi @timonweb !

Thank you for your answer, but it doesn’t really work (well, it is just that I don’t know how to resolve the following issue). When I try to

python manage.py makemigrations

I obtain :

You are trying to add a non-nullable field 'slugs_ptr' to forum without a default; we can't do that (the database needs something to populate existing rows)
Please select a fix: 
1) Provide a one-off default now (will be set on all existing rows with a null value for this column) 
2) Quit, and let me add a default in models.py

Here is my code updated :

class Slugs(models.Model):

    model_name_raw = models.CharField(max_length=40, default=None)

    model_name_slug = models.SlugField(max_length=80, default=None, blank=True)

    def save(self, *args, **kwargs):

        self.model_name_slug = slugify(self.model_name_raw)

        super().save(*args, **kwargs)

    def __str__(self):

        return self.model_name_raw

# Create your models here.

class Forum(Slugs):

    forum_description = models.CharField(max_length=100)

class Topic(Slugs):

    topic_forum = models.ForeignKey(Forum, related_name="topic_forum", on_delete=models.CASCADE)

    topic_description = models.CharField(max_length=100)

    topic_author = models.ForeignKey(User, related_name="topic_author", on_delete=models.CASCADE)

    topic_answers = models.IntegerField(default=0)

    topic_last_answer_by = models.ForeignKey(User,related_name="topic_last_answer_by",on_delete=models.CASCADE)