add migration

src/pretix/base/migrations/0158_mails_by_sales_channel.py

@@ -0,0 +1,39 @@
+# Generated by Django 3.0.8 on 2020-07-24 09:05
+
+from django.db import migrations
+
+from pretix.base.channels import get_all_sales_channels
+
+def set_sales_channels(apps, schema_editor):
+    # We now allow restricting some mails to certain sales channels
+    # The default is changing from all channels to "web" only
+    # Therefore, for existing events, we enable all sales channels
+    Event_SettingsStore = apps.get_model('pretixbase', 'Event_SettingsStore')
+    Event = apps.get_model('pretixbase', 'Event')
+    all_sales_channels = "[" + ", ".join('"' + sc + '"' for sc in get_all_sales_channels()) + "]"
+    batch_size = 1000
+    Event_SettingsStore.objects.bulk_create([
+        Event_SettingsStore(
+            object=event,
+            key="mail_sales_channel_placed_paid",
+            value=all_sales_channels)
+        for event in Event.objects.all()
+    ], batch_size=batch_size)
+    Event_SettingsStore.objects.bulk_create([
+        Event_SettingsStore(
+            object=event,
+            key="mail_sales_channel_ticket_reminder",
+            value=all_sales_channels)
+        for event in Event.objects.all()
+    ], batch_size=batch_size)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0157_auto_20200712_0932'),
+    ]
+
+    operations = [
+        migrations.RunPython(set_sales_channels, migrations.RunPython.noop),
+    ]