bookwyrm/bookwyrm/migrations/0005_auto_20200221_1645.py

# Generated by Django 3.0.3 on 2020-02-21 16:45
import re
from django.db import migrations, models


def populate_identifiers(app_registry, schema_editor):
    db_alias = schema_editor.connection.alias
    tags = app_registry.get_model('bookwyrm', 'Tag')
    for tag in tags.objects.using(db_alias):
        tag.identifier = re.sub(r'\W+', '-', tag.name).lower()
        tag.save()


class Migration(migrations.Migration):

    dependencies = [
        ('bookwyrm', '0004_tag'),
    ]

    operations = [
        migrations.AddField(
            model_name='tag',
            name='identifier',
            field=models.CharField(max_length=100, null=True),
        ),
        migrations.AlterField(
            model_name='tag',
            name='name',
            field=models.CharField(max_length=100),
        ),
        migrations.RunPython(populate_identifiers),
    ]