Django Rest Framework, conditionally required parameters

mixins.py

from rest_framework import serializers

#
# Use in your Serializer for fields that you want to be required only when certain crieteria is met
#
class ConditionalRequiredMixin(serializers.BaseSerializer):
    # List of fields that may be required
    conditionally_required: List[str] = []

    # Override in your serializer to set required attribute
    # on conditional fields 
    def condition_check(self) -> bool:
        return False

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

        for field_name, field in self.fields.items():
            if field_name in self.conditionally_required:
                field.required = getattr(self, "condition_check")()

serializers.py

# Quick usage

class MyAwesomeSerializer(ConditionalRequiredMixin, serializers.ModelSerializer):
    conditionally_required = ["foo", "bar"]

    # Check if baz contains "Hit me one more time." and set fields foo and bar as required.                             
    def condition_check(self) -> bool:
        return self.context["request"].data["baz"] == "Hit me one more time."
                              
    class Meta:
      model = Awesome
      fields = [ "foo", "bar", "baz" ]