Model, view and serializer for instance-level policies

api/funkwhale_api/federation/fields.py

@@ -0,0 +1,18 @@
+from rest_framework import serializers
+
+from . import models
+
+
+class ActorRelatedField(serializers.EmailField):
+    def to_representation(self, value):
+        return value.full_username
+
+    def to_interal_value(self, value):
+        value = super().to_interal_value(value)
+        username, domain = value.split("@")
+        try:
+            return models.Actor.objects.get(
+                preferred_username=username, domain_id=domain
+            )
+        except models.Actor.DoesNotExist:
+            raise serializers.ValidationError("Invalid actor name")