new

backend/community/serializers.py

@@ -29,13 +29,16 @@ class ActivitySerializer(serializers.ModelSerializer):
         return config
 
 class ActivitySignupSerializer(serializers.ModelSerializer):
-    activity_info = ActivitySerializer(source='activity', read_only=True)
+    activity_info = serializers.SerializerMethodField()
 
     class Meta:
         model = ActivitySignup
         fields = ['id', 'activity', 'activity_info', 'user', 'signup_time', 'status', 'signup_info']
         read_only_fields = ['signup_time', 'status', 'user']
 
+    def get_activity_info(self, obj):
+        return ActivitySerializer(obj.activity).data
+
 class TopicMediaSerializer(serializers.ModelSerializer):
     url = serializers.SerializerMethodField()