DRF_Template/backend/subscriptions/serializers.py

from accounts.serializers import SimpleCustomUserSerializer
from rest_framework import serializers
from subscriptions.models import StripePrice, SubscriptionPlan, UserSubscription


class SimpleStripePriceSerializer(serializers.ModelSerializer):

    class Meta:
        model = StripePrice
        fields = ["price", "currency", "prorated"]


class SubscriptionPlanSerializer(serializers.ModelSerializer):

    class Meta:
        model = SubscriptionPlan
        fields = [
            "id",
            "name",
            "description",
            "annual_price",
            "monthly_price",
            "group_exclusive",
        ]

    def to_representation(self, instance):
        representation = super().to_representation(instance)
        representation["annual_price"] = SimpleStripePriceSerializer(
            instance.annual_price, many=False
        ).data
        representation["monthly_price"] = SimpleStripePriceSerializer(
            instance.monthly_price, many=False
        ).data
        return representation


class UserSubscriptionSerializer(serializers.ModelSerializer):
    date = serializers.DateTimeField(format="%m-%d-%Y %I:%M %p", read_only=True)

    class Meta:
        model = UserSubscription
        fields = ["id", "user", "user_group", "subscription", "date", "valid", "annual"]

    def to_representation(self, instance):
        representation = super().to_representation(instance)
        representation["user"] = SimpleCustomUserSerializer(
            instance.user, many=False
        ).data
        representation["subscription"] = SubscriptionPlanSerializer(
            instance.subscription, many=False
        ).data
        return representation