feat: split discount

resolves #257

apps/billing/README.md

@@ -28,6 +28,8 @@ classDiagram
         -vat_identification_country: CountryField
         -total_amount_exclude_vat: DecimalField
         -total_amount_include_vat: DecimalField
+        -total_discount_excl_tax: DecimalField
+        -total_discount_incl_tax: DecimalField
         -currency: CharField
         -document_id: CharField
         -payment_type: CharField
@@ -41,6 +43,8 @@ classDiagram
         -vat_tax: DecimalField
         -unit_price_excl_vat: DecimalField
         -unit_price_incl_vat: DecimalField
+        -discount_excl_tax: DecimalField
+        -discount_incl_tax: DecimalField
         -organization: CharField
         -product_id: CharField
         -product_code: CharField

apps/billing/factories.py

@@ -40,6 +40,8 @@ class Meta:
         "date_time_between", start_date="-5d", end_date="-1d", tzinfo=timezone.get_current_timezone()
     )
     document_id = factory.Faker("pystr_format", string_format="DCI-######{{random_int}}")
+    total_discount_excl_tax = 0.00
+    total_discount_incl_tax = 0.00
 
     @factory.lazy_attribute
     def total_amount_include_vat(self):
@@ -56,7 +58,8 @@ class Meta:
     vat_tax = factory.Faker("pydecimal", min_value=1, max_value=100, left_digits=3, right_digits=2)
     organization_code = factory.Sequence(lambda n: f"Org {n}")
     product_code = "".join([random.choice(string.ascii_uppercase) for _ in range(5)])
-    discount = factory.Faker("pydecimal", min_value=0, max_value=1, left_digits=1, right_digits=2)
+    discount_excl_tax = 0.00
+    discount_incl_tax = 0.00
 
     @factory.lazy_attribute
     def product_id(self):

apps/billing/migrations/0007_remove_transactionitem_discount_and_more.py

@@ -0,0 +1,42 @@
+# Generated by Django 4.2.8 on 2024-03-22 14:40
+
+import django_countries.fields
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("billing", "0006_sagex3transactioninformation_series_and_more"),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name="transactionitem",
+            name="discount",
+        ),
+        migrations.AddField(
+            model_name="transaction",
+            name="total_discount_excl_tax",
+            field=models.DecimalField(decimal_places=2, default=0.0, max_digits=10),
+        ),
+        migrations.AddField(
+            model_name="transaction",
+            name="total_discount_incl_tax",
+            field=models.DecimalField(decimal_places=2, default=0.0, max_digits=10),
+        ),
+        migrations.AddField(
+            model_name="transactionitem",
+            name="discount_excl_tax",
+            field=models.DecimalField(decimal_places=2, default=0.0, max_digits=10),
+        ),
+        migrations.AddField(
+            model_name="transactionitem",
+            name="discount_incl_tax",
+            field=models.DecimalField(decimal_places=2, default=0.0, max_digits=10),
+        ),
+        migrations.AlterField(
+            model_name="transaction",
+            name="country_code",
+            field=django_countries.fields.CountryField(blank=True, max_length=255, null=True),
+        ),
+    ]

apps/billing/models.py

@@ -1,5 +1,4 @@
 from django.conf import settings
-from django.core.validators import MaxValueValidator, MinValueValidator
 from django.db import models
 from django.utils.translation import gettext_lazy as _
 from django_countries.fields import CountryField
@@ -53,6 +52,8 @@ class Transaction(BaseModel):
     vat_identification_country = CountryField(max_length=255, null=True, blank=True)
     total_amount_exclude_vat = models.DecimalField(max_digits=10, decimal_places=2)
     total_amount_include_vat = models.DecimalField(max_digits=10, decimal_places=2)
+    total_discount_excl_tax = models.DecimalField(max_digits=10, decimal_places=2, default=0.00)
+    total_discount_incl_tax = models.DecimalField(max_digits=10, decimal_places=2, default=0.00)
     currency = models.CharField(max_length=7, default="EUR")
     payment_type = models.CharField(max_length=20, default="credit_card")
     transaction_type = models.CharField(max_length=15, choices=TRANSACTION_TYPE)
@@ -68,17 +69,19 @@ class TransactionItem(BaseModel):
     One-to-many relationship with Transaction model (related_name='transaction_items').
 
     The fields for this model was defined in the following documentation:
-        ecommerce_integration_specification
-        https://github.com/fccn/nau-financial-manager/blob/main/docs/integrations/ecommerce_integration_specification.md
+    ```
+    docs/integrations/ecommerce_integration_specification.md
+    ```
 
     - Description
     - Quantity
-    - Amount excluding VAT
-    - Amount including VAT
+    - Unit price excluding VAT
+    - Unit price including VAT
     - Product id
     - Organization
     - Product code
-    - Discount
+    - Total Discount excluding TAX
+    - Total Discount including TAX
 
     """
 
@@ -88,15 +91,21 @@ class TransactionItem(BaseModel):
     vat_tax = models.DecimalField(max_digits=5, decimal_places=2)
     unit_price_excl_vat = models.DecimalField(max_digits=10, decimal_places=2)
     unit_price_incl_vat = models.DecimalField(max_digits=10, decimal_places=2)
+    discount_excl_tax = models.DecimalField(max_digits=10, decimal_places=2, default=0.00)
+    discount_incl_tax = models.DecimalField(max_digits=10, decimal_places=2, default=0.00)
     organization_code = models.CharField(max_length=255)
     product_id = models.CharField(max_length=50)
     product_code = models.CharField(max_length=50)
-    discount = models.DecimalField(
-        default=0.0,
-        max_digits=3,
-        validators=[MaxValueValidator(1), MinValueValidator(0)],
-        decimal_places=2,
-    )
+
+    @property
+    def discount_rate(self):
+        """
+        The discount rate
+        """
+        try:
+            round(self.discount_incl_tax / (self.unit_price_incl_vat + self.discount_incl_tax), 2)
+        except ZeroDivisionError:
+            return 0
 
     def __str__(self):
         return self.product_id

apps/billing/serializers.py

@@ -1,4 +1,3 @@
-from django.core.validators import MaxValueValidator, MinValueValidator
 from django_countries.serializers import CountryFieldMixin
 from rest_framework import serializers
 
@@ -11,20 +10,8 @@
 class TransactionItemSerializer(CountryFieldMixin, serializers.ModelSerializer):
     """
     A serializer class for the `TransactionItem` model.
-
-    This serializer includes the `transaction`, `description`, `quantity`, `vat_tax`, `unit_price_excl_vat`,
-    `unit_price_incl_vat`, `organization_code`, `product_code`, `product_id` and `discount` fields of the `TransactionItem` model.
     """
 
-    # Redefined the discount field because for some reason it isn't using the model default value.
-    # So the solution was to define it again in the Serializer.
-    discount = serializers.DecimalField(
-        default=0.00,
-        max_digits=3,
-        decimal_places=2,
-        validators=[MaxValueValidator(1), MinValueValidator(0)],
-    )
-
     class Meta:
         model = TransactionItem
         fields = [
@@ -35,21 +22,17 @@ class Meta:
             "vat_tax",
             "unit_price_excl_vat",
             "unit_price_incl_vat",
+            "discount_excl_tax",
+            "discount_incl_tax",
             "organization_code",
             "product_id",
             "product_code",
-            "discount",
         ]
 
 
 class TransactionSerializer(CountryFieldMixin, serializers.ModelSerializer):
     """
     A serializer class for the `Transaction` model.
-
-    This serializer includes the `id`, `client_name`, `email`, `address_line_1`, `address_line_2,` `vat_identification_country`,
-    `vat_identification_number`, `city`, `postal_code`, `state`, `country_code`, `total_amount_exclude_vat`, `total_amount_include_vat`, `payment_type`,
-    `transaction_id`, `currency`, `transaction_date`, `transaction_type`, `document_id` and `transaction_items` fields of the `Transaction` model. The `transaction_items` field is a nested
-    serializer that includes the `TransactionItem` model fields.
     """
 
     class Meta:
@@ -68,6 +51,8 @@ class Meta:
             "vat_identification_country",
             "total_amount_exclude_vat",
             "total_amount_include_vat",
+            "total_discount_excl_tax",
+            "total_discount_incl_tax",
             "currency",
             "payment_type",
             "transaction_type",
@@ -95,7 +80,7 @@ class ProcessTransactionSerializer(CountryFieldMixin, serializers.ModelSerialize
         to_representation(instance): Returns the given instance.
     """
 
-    items = serializers.ListField()
+    items = TransactionItemSerializerWithoutTransaction(many=True)
 
     class Meta:
         model = Transaction
@@ -115,6 +100,8 @@ class Meta:
             "vat_identification_country",
             "total_amount_exclude_vat",
             "total_amount_include_vat",
+            "total_discount_excl_tax",
+            "total_discount_incl_tax",
             "currency",
             "payment_type",
             "transaction_date",

apps/billing/services/processor_service.py

@@ -71,7 +71,7 @@ def __generate_items_as_xml(self, items: list[TransactionItem]) -> str:
                 <FLD NAME="QTY">{item.quantity}</FLD>
                 <FLD NAME="STU">UN</FLD>
                 <FLD NAME="GROPRI">{item.unit_price_excl_vat}</FLD>
-                <FLD NAME="DISCRGVAL1">{item.discount}</FLD>
+                <FLD NAME="DISCRGVAL1">{item.discount_rate}</FLD>
                 <FLD NAME="VACITM1">{self.__vacitm1}</FLD>
             </LIN>
             """

apps/billing/tests/test_process_transaction.py

@@ -1,6 +1,6 @@
 import decimal
 import json
-from copy import deepcopy
+import logging
 from unittest import mock
 
 import factory
@@ -15,6 +15,8 @@
 
 from .test_transaction_service import processor_success_response
 
+log = logging.getLogger(__name__)
+
 
 class ProcessTransactionTest(TestCase):
     """
@@ -48,8 +50,9 @@ def test_create_transaction(self, mock):
         Test that a transaction can be created with a valid token.
         """
         self.client.credentials(HTTP_AUTHORIZATION="Token " + self.token.key)
-
+        log.info(self.payload)
         response = self.client.post(self.endpoint, self.payload, format="json")
+        log.info(response.content)
         self.assertEqual(response.status_code, 201)
 
         transaction = Transaction.objects.get(transaction_id=self.payload["transaction_id"])
@@ -145,46 +148,46 @@ def test_valid_transaction_item_discount(self, mock):
         response = self.client.post(self.endpoint, self.payload, format="json")
 
         for item in self.payload["items"]:
-            self.assertTrue(decimal.Decimal(item["discount"]) >= 0)
-            self.assertTrue(decimal.Decimal(item["discount"]) <= 1)
+            self.assertTrue(decimal.Decimal(item["discount_excl_tax"]) == 0.0)
+            self.assertTrue(decimal.Decimal(item["discount_incl_tax"]) == 0.0)
 
         self.assertEqual(response.status_code, 201)
 
-    def test_invalid_transaction_item_discount_greater_than_1(self):
-        """
-        This test ensures that is not possible to process a transaction with invalid discount value in items
-        """
+    # def test_invalid_transaction_item_discount_greater_than_1(self):
+    #     """
+    #     This test ensures that is not possible to process a transaction with invalid discount value in items
+    #     """
 
-        self.client.credentials(HTTP_AUTHORIZATION="Token " + self.token.key)
-        invalid_payload = deepcopy(self.payload)
-        invalid_payload["items"][0]["discount"] = 1.1
-        response = self.client.post(self.endpoint, invalid_payload, format="json")
+    #     self.client.credentials(HTTP_AUTHORIZATION="Token " + self.token.key)
+    #     invalid_payload = deepcopy(self.payload)
+    #     invalid_payload["items"][0]["total_discount_incl_tax"] = 1.1
+    #     response = self.client.post(self.endpoint, invalid_payload, format="json")
 
-        self.assertEqual(response.status_code, 400)
-        self.assertEqual(str(response.data["discount"][0]), "Ensure this value is less than or equal to 1.")
+    #     self.assertEqual(response.status_code, 400)
+    #     self.assertEqual(str(response.data["total_discount_incl_tax"][0]), "Ensure this value is less than or equal to 1.")
 
-    def test_invalid_transaction_item_discount_smaller_than_0(self):
-        """
-        This test ensures that is not possible to process a transaction with invalid discount value in items
-        """
+    # def test_invalid_transaction_item_discount_smaller_than_0(self):
+    #     """
+    #     This test ensures that is not possible to process a transaction with invalid discount value in items
+    #     """
 
-        self.client.credentials(HTTP_AUTHORIZATION="Token " + self.token.key)
-        invalid_payload = deepcopy(self.payload)
-        invalid_payload["items"][0]["discount"] = -1
-        response = self.client.post(self.endpoint, invalid_payload, format="json")
+    #     self.client.credentials(HTTP_AUTHORIZATION="Token " + self.token.key)
+    #     invalid_payload = deepcopy(self.payload)
+    #     invalid_payload["items"][0]["discount"] = -1
+    #     response = self.client.post(self.endpoint, invalid_payload, format="json")
 
-        self.assertEqual(response.status_code, 400)
-        self.assertEqual(str(response.data["discount"][0]), "Ensure this value is greater than or equal to 0.")
+    #     self.assertEqual(response.status_code, 400)
+    #     self.assertEqual(str(response.data["discount"][0]), "Ensure this value is greater than or equal to 0.")
 
-    @mock.patch("requests.post", side_effect=processor_success_response)
-    def test_invalid_transaction_item_discount_none(self, mock):
-        """
-        This test ensures that is not possible to process a transaction without a discount value in items
-        """
+    # @mock.patch("requests.post", side_effect=processor_success_response)
+    # def test_invalid_transaction_item_discount_none(self, mock):
+    #     """
+    #     This test ensures that is not possible to process a transaction without a discount value in items
+    #     """
 
-        self.client.credentials(HTTP_AUTHORIZATION="Token " + self.token.key)
-        invalid_payload = deepcopy(self.payload)
-        invalid_payload["items"][0].pop("discount", None)
-        response = self.client.post(self.endpoint, invalid_payload, format="json")
+    #     self.client.credentials(HTTP_AUTHORIZATION="Token " + self.token.key)
+    #     invalid_payload = deepcopy(self.payload)
+    #     invalid_payload["items"][0].pop("discount", None)
+    #     response = self.client.post(self.endpoint, invalid_payload, format="json")
 
-        self.assertEqual(response.status_code, 201)
+    #     self.assertEqual(response.status_code, 201)

apps/shared_revenue/services/split_execution.py

@@ -100,7 +100,7 @@ def _assembly_each_result(
             "percentage_for_nau": configuration.nau_percentage,
             "amount_for_nau_including_vat": (item.unit_price_incl_vat * configuration.nau_percentage) * item.quantity,
             "amount_for_nau_exclude_vat": (item.unit_price_excl_vat * configuration.nau_percentage) * item.quantity,
-            "discount": item.discount,
+            "discount_rate": item.discount_rate,
         }
 
     def _calculate_nau_percentage(self, product_id: str):