from django.db import migrations, models

def raise_error(apps, schema_editor):

    # Test operation in non-atomic migration is not wrapped in transaction

    Publisher = apps.get_model("migrations", "Publisher")

    Publisher.objects.create(name="Test Publisher")

    raise RuntimeError("Abort migration")

class Migration(migrations.Migration):

    atomic = False

    operations = [

        migrations.CreateModel(

            "Publisher",

            [

                ("name", models.CharField(primary_key=True, max_length=255)),

            ],

        ),

        migrations.RunPython(raise_error),

        migrations.CreateModel(

            "Book",

            [

                ("title", models.CharField(primary_key=True, max_length=255)),

                (

                    "publisher",

                    models.ForeignKey(

                        "migrations.Publisher", models.SET_NULL, null=True

                    ),

                ),

            ],

        ),

    ]