yuyu/api/serializers.py

from djmoney.contrib.django_rest_framework import MoneyField
from rest_framework import serializers

from core.models import Invoice
from core.component import component


class InvoiceComponentSerializer(serializers.ModelSerializer):
    adjusted_end_date = serializers.DateTimeField()
    price_charged = MoneyField(max_digits=10, decimal_places=0)
    price_charged_currency = serializers.CharField(source="price_charged.currency")


def generate_invoice_component_serializer(model):
    """
    Generate Invoice Component Serializer for particular model
    :param model: The invoice component model
    :return: serializer for particular model
    """
    name = type(model).__name__
    meta_params = {
        "model": model,
        "fields": "__all__"
    }
    meta_class = type("Meta", (object,), meta_params)
    serializer_class = type(f"{name}Serializer", (InvoiceComponentSerializer,), {"Meta": meta_class})

    return serializer_class


class InvoiceSerializer(serializers.ModelSerializer):
    subtotal = MoneyField(max_digits=10, decimal_places=0)
    subtotal_currency = serializers.CharField(source="subtotal.currency")

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        for field, model in component.INVOICE_COMPONENT_MODEL.items():
            self.fields[field] = generate_invoice_component_serializer(model)(many=True)

    class Meta:
        model = Invoice
        fields = '__all__'


class SimpleInvoiceSerializer(serializers.ModelSerializer):
    subtotal = MoneyField(max_digits=10, decimal_places=0)
    subtotal_currency = serializers.CharField(source="subtotal.currency")

    class Meta:
        model = Invoice
        fields = ['id', 'start_date', 'end_date', 'state', 'tax', 'subtotal', 'subtotal_currency', 'total']