userausfall/userausfall/rest_api/serializers.py

from rest_framework import serializers

from userausfall.models import TrustBridge, User


class UserSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = User
        fields = ["username"]
        # the UniqueValidator for username prevents successful validation for existing users
        extra_kwargs = {"username": {"validators": []}}


class TrustBridgeSerializer(serializers.HyperlinkedModelSerializer):
    trust_giver = UserSerializer()

    class Meta:
        model = TrustBridge
        fields = ["is_trusted", "trust_giver"]
        read_only_fields = ["is_trusted"]

    def update(self, instance: TrustBridge, validated_data):
        instance.trust_giver, _ = User.objects.get_or_create(username=validated_data["trust_giver"]["username"])
        instance.save()
        return instance