Fixes up some issues with the migrations and type mismatches

src/documents/migrations/1026_transition_to_celery.py

@@ -0,0 +1,74 @@
+# Generated by Django 4.1.1 on 2022-09-27 19:31
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+def _attempted_task(apps, schema_editor):
+    """
+    Remove any existing attempted_task one to one fields.
+    """
+    task_model = apps.get_model("documents", "PaperlessTask")
+
+    for task in task_model.objects.all():
+        if hasattr(task, "attempted_task"):
+            task.attempted_task = None
+            task.save()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("django_celery_results", "0011_taskresult_periodic_task_name"),
+        ("documents", "1025_alter_savedviewfilterrule_rule_type"),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name="paperlesstask",
+            name="created",
+        ),
+        migrations.RemoveField(
+            model_name="paperlesstask",
+            name="name",
+        ),
+        migrations.RemoveField(
+            model_name="paperlesstask",
+            name="started",
+        ),
+        # Ensure any existing PaperlessTask.attempted_task are nulled
+        # This ensures nothing is pointing to a django-q model
+        migrations.RunPython(
+            code=_attempted_task,
+            reverse_code=migrations.RunPython.noop,
+        ),
+        # Remove the field from the model
+        migrations.RemoveField(
+            model_name="paperlesstask",
+            name="attempted_task",
+        ),
+        # Add the field back, pointing to the correct model
+        # This resolves a problem where the temporary change in 1022
+        # results in a type mismatch
+        migrations.AddField(
+            model_name="paperlesstask",
+            name="attempted_task",
+            field=models.OneToOneField(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.CASCADE,
+                related_name="attempted_task",
+                to="django_celery_results.taskresult",
+            ),
+        ),
+        # Drop the django-q tables entirely
+        migrations.RunSQL(
+            "DROP TABLE IF EXISTS django_q_ormq", reverse_sql=migrations.RunSQL.noop
+        ),
+        migrations.RunSQL(
+            "DROP TABLE IF EXISTS django_q_schedule", reverse_sql=migrations.RunSQL.noop
+        ),
+        migrations.RunSQL(
+            "DROP TABLE IF EXISTS django_q_task", reverse_sql=migrations.RunSQL.noop
+        ),
+    ]