Run Migrations! Converts attributes to use pickle v4

evennia/typeclasses/migrations/0012_attrs_to_picklev4_may_be_slow.py

@@ -0,0 +1,29 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.16 on 2019-01-30 20:56
+from __future__ import unicode_literals
+
+from copy import deepcopy
+from base64 import b64encode, b64decode
+from django.db import migrations
+from pickle import dumps, loads
+from evennia.utils.utils import to_bytes
+
+
+def forwards(apps, schema_editor):
+    Attribute = apps.get_model('typeclasses', 'Attribute')
+    for attr in Attribute.objects.all():
+        # we need to re-assign the Attribute it's own value to make sure pickle switches from v2 to v4,
+        # otherwise we will not be able to search db by-value.
+        attr.db_value = attr.db_value
+        attr.save(update_fields=["db_value"])
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('typeclasses', '0011_auto_20190128_1820'),
+    ]
+
+    operations = [
+        migrations.RunPython(forwards, migrations.RunPython.noop),
+    ]