providers/proxy: add error handing when field is already gone

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

authentik/providers/proxy/migrations/0001_squashed_0014_proxy_v2.py

@@ -2,6 +2,7 @@
 
 import django.db.models.deletion
 from django.apps.registry import Apps
+from django.core.exceptions import FieldError
 from django.db import migrations, models
 from django.db.backends.base.schema import BaseDatabaseSchemaEditor
 
@@ -14,9 +15,13 @@ def migrate_defaults(apps: Apps, schema_editor: BaseDatabaseSchemaEditor):
     from authentik.providers.proxy.models import ProxyProvider
 
     db_alias = schema_editor.connection.alias
+    try:
         for provider in ProxyProvider.objects.using(db_alias).filter(jwt_alg=JWTAlgorithms.RS256):
             provider.set_oauth_defaults()
             provider.save()
+    except FieldError:
+        # If the jwt_alg field doesn't exist, just ignore this migration
+        pass
 
 
 def migrate_mode(apps: Apps, schema_editor: BaseDatabaseSchemaEditor):

authentik/providers/proxy/migrations/0014_proxy_v2.py

@@ -1,6 +1,7 @@
 # Generated by Django 3.2.6 on 2021-09-09 11:24
 
 from django.apps.registry import Apps
+from django.core.exceptions import FieldError
 from django.db import migrations
 from django.db.backends.base.schema import BaseDatabaseSchemaEditor
 
@@ -10,9 +11,13 @@ def migrate_defaults(apps: Apps, schema_editor: BaseDatabaseSchemaEditor):
     from authentik.providers.proxy.models import ProxyProvider
 
     db_alias = schema_editor.connection.alias
+    try:
         for provider in ProxyProvider.objects.using(db_alias).filter(jwt_alg=JWTAlgorithms.RS256):
             provider.set_oauth_defaults()
             provider.save()
+    except FieldError:
+        # If the jwt_alg field doesn't exist, just ignore this migration
+        pass
 
 
 class Migration(migrations.Migration):