[FIXED] How to change the default "non_field_errors" message with Django Rest Framework

Issue

I'm trying to change the default error message value of a "non field error" in a serializer. Here's what I've got so far:

class ItemSerializer(serializers.ModelSerializer):
    class Meta:
        model = Item
        fields = "__all__"
        extra_kwargs = {
            "non_field_errors": {
                "error_messages": {
                    "unique": "There exists an item with this name already!"
                }
            }
        }

ItemSerializer behaves as expected, but the code above has no effect on the output.

Solution

You can change the default error message of non_field_errors by adding a UniqueTogetherValidator in validators (inside your Meta class) like so:

validators = [
      UniqueTogetherValidator(
       queryset=Item.objects.all(),
       fields=["org", "item_name"],
       message="Duplicate items!",
     )
]

Answered By - kureal