Merge pull request saleor#4442 from mirumee/4318/voucher_once_per_user

Add voucher once per user

CHANGELOG.md

@@ -8,6 +8,7 @@ All notable, unreleased changes to this project will be documented in this file.
 - Fix form reloading - #4467 by @dominik-zeglen
 - Fix time zone based tests - #4468 by @fowczarek
 - Move Django Debug Toolbar requirement to the "dev" one (also downgrade it 2.0 -> 1.11, see PR) - #4454 by @derenio
+- Add voucher once per customer - #4442 by @fowczarek
 
 
 ## 2.8.0

saleor/checkout/models.py

@@ -90,6 +90,9 @@ def __iter__(self):
     def __len__(self):
         return self.lines.count()
 
+    def get_customer_email(self):
+        return self.user.email if self.user else self.email
+
     def is_shipping_required(self):
         """Return `True` if any of the lines requires shipping."""
         return any(line.is_shipping_required() for line in self)

saleor/checkout/utils.py

@@ -35,11 +35,12 @@
 from ..discount import VoucherType
 from ..discount.models import NotApplicable, Voucher
 from ..discount.utils import (
+    add_voucher_usage_by_customer,
     decrease_voucher_usage,
     get_products_voucher_discount,
-    get_shipping_voucher_discount,
-    get_value_voucher_discount,
     increase_voucher_usage,
+    remove_voucher_usage_by_customer,
+    validate_voucher_for_checkout,
 )
 from ..giftcard.utils import (
     add_gift_card_code_to_checkout,
@@ -767,12 +768,8 @@ def _get_shipping_voucher_discount_for_checkout(voucher, checkout, discounts=Non
         )
         raise NotApplicable(msg)
 
-    return get_shipping_voucher_discount(
-        voucher,
-        calculate_checkout_subtotal(checkout, discounts).gross,
-        calculate_checkout_shipping(checkout, discounts).gross,
-        checkout.quantity,
-    )
+    shipping_price = calculate_checkout_shipping(checkout, discounts).gross
+    return voucher.get_discount_amount_for(shipping_price)
 
 
 def _get_products_voucher_discount(checkout, voucher, discounts=None):
@@ -798,18 +795,18 @@ def _get_products_voucher_discount(checkout, voucher, discounts=None):
             "Voucher not applicable", "This offer is only valid for selected items."
         )
         raise NotApplicable(msg)
-    subtotal = calculate_checkout_subtotal(checkout, discounts).gross
-    return get_products_voucher_discount(voucher, prices, subtotal, checkout.quantity)
+    return get_products_voucher_discount(voucher, prices)
 
 
 def get_voucher_discount_for_checkout(voucher, checkout, discounts=None):
     """Calculate discount value depending on voucher and discount types.
 
     Raise NotApplicable if voucher of given type cannot be applied.
     """
+    validate_voucher_for_checkout(voucher, checkout, discounts)
     if voucher.type == VoucherType.ENTIRE_ORDER:
         subtotal = calculate_checkout_subtotal(checkout, discounts).gross
-        return get_value_voucher_discount(voucher, subtotal, checkout.quantity)
+        return voucher.get_discount_amount_for(subtotal)
     if voucher.type == VoucherType.SHIPPING:
         return _get_shipping_voucher_discount_for_checkout(voucher, checkout, discounts)
     if voucher.type in (
@@ -994,6 +991,8 @@ def _get_voucher_data_for_order(checkout):
         return {}
 
     increase_voucher_usage(voucher)
+    if voucher.apply_once_per_customer:
+        add_voucher_usage_by_customer(voucher, checkout.get_customer_email())
     return {
         "voucher": voucher,
         "discount_amount": checkout.discount_amount,
@@ -1034,7 +1033,7 @@ def _process_user_data_for_order(checkout):
 
     return {
         "user": checkout.user,
-        "user_email": checkout.user.email if checkout.user else checkout.email,
+        "user_email": checkout.get_customer_email(),
         "billing_address": billing_address,
         "customer_note": checkout.note,
     }
@@ -1135,7 +1134,10 @@ def prepare_order_data(*, checkout: Checkout, tracking_code: str, discounts) ->
 
 def abort_order_data(order_data: dict):
     if "voucher" in order_data:
-        decrease_voucher_usage(order_data["voucher"])
+        voucher = order_data["voucher"]
+        decrease_voucher_usage(voucher)
+        if "user_email" in order_data:
+            remove_voucher_usage_by_customer(voucher, order_data["user_email"])
 
 
 @transaction.atomic

saleor/dashboard/order/forms.py

@@ -58,7 +58,7 @@ class Meta:
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
-        if not self.instance.get_user_current_email():
+        if not self.instance.get_customer_email():
             self.fields.pop("notify_customer")
 
     def clean(self):
@@ -548,7 +548,7 @@ class Meta:
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
-        if not self.instance.order.get_user_current_email():
+        if not self.instance.order.get_customer_email():
             self.fields.pop("send_mail")
 
 
@@ -675,7 +675,7 @@ def __init__(self, *args, **kwargs):
         order = kwargs.pop("order")
         super().__init__(*args, **kwargs)
         self.instance.order = order
-        if not order.get_user_current_email():
+        if not order.get_customer_email():
             self.fields.pop("send_mail")
 
 

saleor/dashboard/order/utils.py

@@ -8,11 +8,7 @@
 from ...core.taxes import zero_money
 from ...discount import VoucherType
 from ...discount.models import NotApplicable
-from ...discount.utils import (
-    get_products_voucher_discount,
-    get_shipping_voucher_discount,
-    get_value_voucher_discount,
-)
+from ...discount.utils import get_products_voucher_discount, validate_voucher_in_order
 
 INVOICE_TEMPLATE = "dashboard/order/pdf/invoice.html"
 PACKING_SLIP_TEMPLATE = "dashboard/order/pdf/packing_slip.html"
@@ -140,9 +136,7 @@ def get_products_voucher_discount_for_order(order, voucher):
             "Voucher not applicable", "This offer is only valid for selected items."
         )
         raise NotApplicable(msg)
-    return get_products_voucher_discount(
-        voucher, prices, order.get_subtotal().gross, order.get_total_quantity()
-    )
+    return get_products_voucher_discount(voucher, prices)
 
 
 def get_voucher_discount_for_order(order):
@@ -152,18 +146,12 @@ def get_voucher_discount_for_order(order):
     """
     if not order.voucher:
         return zero_money()
+    validate_voucher_in_order(order)
     subtotal = order.get_subtotal()
     if order.voucher.type == VoucherType.ENTIRE_ORDER:
-        return get_value_voucher_discount(
-            order.voucher, subtotal.gross, order.get_total_quantity()
-        )
+        return order.voucher.get_discount_amount_for(subtotal.gross)
     if order.voucher.type == VoucherType.SHIPPING:
-        return get_shipping_voucher_discount(
-            order.voucher,
-            subtotal.gross,
-            order.shipping_price,
-            order.get_total_quantity(),
-        )
+        return order.voucher.get_discount_amount_for(order.shipping_price)
     if order.voucher.type in (
         VoucherType.PRODUCT,
         VoucherType.COLLECTION,

saleor/discount/models.py

@@ -57,6 +57,7 @@ class Voucher(models.Model):
     # this field indicates if discount should be applied per order or
     # individually to every item
     apply_once_per_order = models.BooleanField(default=False)
+    apply_once_per_customer = models.BooleanField(default=False)
     discount_value_type = models.CharField(
         max_length=10,
         choices=DiscountValueType.CHOICES,
@@ -165,6 +166,26 @@ def validate_min_checkout_items_quantity(self, quantity):
                 min_checkout_items_quantity=min_checkout_items_quantity,
             )
 
+    def validate_once_per_customer(self, customer_email):
+        voucher_customer = VoucherCustomer.objects.filter(
+            voucher=self, customer_email=customer_email
+        )
+        if voucher_customer:
+            msg = pgettext(
+                "Voucher not applicable", "This offer is valid only once per customer."
+            )
+            raise NotApplicable(msg)
+
+
+class VoucherCustomer(models.Model):
+    voucher = models.ForeignKey(
+        Voucher, related_name="customers", on_delete=models.CASCADE
+    )
+    customer_email = models.EmailField()
+
+    class Meta:
+        unique_together = (("voucher", "customer_email"),)
+
 
 class SaleQueryset(models.QuerySet):
     def active(self, date):

saleor/discount/utils.py

@@ -6,8 +6,9 @@
 from django.utils.translation import pgettext
 
 from ..core.taxes import zero_money
+from ..core.taxes.interface import calculate_checkout_subtotal
 from . import DiscountInfo
-from .models import NotApplicable, Sale
+from .models import NotApplicable, Sale, VoucherCustomer
 
 
 def increase_voucher_usage(voucher):
@@ -22,6 +23,28 @@ def decrease_voucher_usage(voucher):
     voucher.save(update_fields=["used"])
 
 
+def add_voucher_usage_by_customer(voucher, customer_email):
+    voucher_customer = VoucherCustomer.objects.filter(
+        voucher=voucher, customer_email=customer_email
+    )
+    if voucher_customer:
+        raise NotApplicable(
+            pgettext(
+                "Voucher not applicable",
+                ("This offer is only valid once per customer."),
+            )
+        )
+    VoucherCustomer.objects.create(voucher=voucher, customer_email=customer_email)
+
+
+def remove_voucher_usage_by_customer(voucher, customer_email):
+    voucher_customer = VoucherCustomer.objects.filter(
+        voucher=voucher, customer_email=customer_email
+    )
+    if voucher_customer:
+        voucher_customer.delete()
+
+
 def are_product_collections_on_sale(product, discount: DiscountInfo):
     """Check if any collection is on sale."""
     discounted_collections = discount.collection_ids
@@ -61,24 +84,28 @@ def calculate_discounted_price(product, price, discounts: Iterable[DiscountInfo]
     return price
 
 
-def get_value_voucher_discount(voucher, total_price, quantity):
-    """Calculate discount value for a voucher of value type."""
-    voucher.validate_min_amount_spent(total_price)
-    voucher.validate_min_checkout_items_quantity(quantity)
-    return voucher.get_discount_amount_for(total_price)
+def validate_voucher_for_checkout(voucher, checkout, discounts):
+    subtotal = calculate_checkout_subtotal(checkout, discounts)
+    customer_email = checkout.get_customer_email()
+    validate_voucher(voucher, subtotal.gross, checkout.quantity, customer_email)
+
 
+def validate_voucher_in_order(order):
+    subtotal = order.get_subtotal()
+    quantity = order.get_total_quantity()
+    customer_email = order.get_customer_email()
+    validate_voucher(order.voucher, subtotal.gross, quantity, customer_email)
 
-def get_shipping_voucher_discount(voucher, total_price, shipping_price, quantity):
-    """Calculate discount value for a voucher of shipping type."""
+
+def validate_voucher(voucher, total_price, quantity, customer_email):
     voucher.validate_min_amount_spent(total_price)
     voucher.validate_min_checkout_items_quantity(quantity)
-    return voucher.get_discount_amount_for(shipping_price)
+    if voucher.apply_once_per_customer:
+        voucher.validate_once_per_customer(customer_email)
 
 
-def get_products_voucher_discount(voucher, prices, total_price, quantity):
+def get_products_voucher_discount(voucher, prices):
     """Calculate discount value for a voucher of product or category type."""
-    voucher.validate_min_amount_spent(total_price)
-    voucher.validate_min_checkout_items_quantity(quantity)
     if voucher.apply_once_per_order:
         return voucher.get_discount_amount_for(min(prices))
     discounts = (voucher.get_discount_amount_for(price) for price in prices)

saleor/graphql/checkout/types.py

@@ -115,6 +115,10 @@ class Meta:
         interfaces = [graphene.relay.Node]
         filter_fields = ["token"]
 
+    @staticmethod
+    def resolve_email(root: models.Checkout, info):
+        return root.get_customer_email()
+
     @staticmethod
     def resolve_total_price(root: models.Checkout, info):
         taxed_total = (

saleor/graphql/discount/mutations.py

@@ -111,6 +111,9 @@ class VoucherInput(graphene.InputObjectType):
     apply_once_per_order = graphene.Boolean(
         description="Voucher should be applied to the cheapest item or entire order."
     )
+    apply_once_per_customer = graphene.Boolean(
+        description="Voucher should be applied once per customer."
+    )
     usage_limit = graphene.Int(
         description="Limit number of times this voucher can be used in total"
     )

saleor/graphql/discount/types.py

@@ -110,6 +110,7 @@ class Meta:
         providing valid voucher codes."""
         only_fields = [
             "apply_once_per_order",
+            "apply_once_per_customer",
             "code",
             "discount_value",
             "discount_value_type",

saleor/graphql/order/types.py

@@ -451,11 +451,7 @@ def resolve_can_finalize(root: models.Order, _info):
     @staticmethod
     @gql_optimizer.resolver_hints(select_related="user")
     def resolve_user_email(root: models.Order, _info):
-        if root.user_email:
-            return root.user_email
-        if root.user_id:
-            return root.user.email
-        return None
+        return root.get_customer_email()
 
     @staticmethod
     def resolve_available_shipping_methods(root: models.Order, _info):

saleor/graphql/schema.graphql

@@ -3135,6 +3135,7 @@ type Voucher implements Node {
   startDate: DateTime!
   endDate: DateTime
   applyOncePerOrder: Boolean!
+  applyOncePerCustomer: Boolean!
   discountValueType: DiscountValueTypeEnum!
   discountValue: Float!
   minAmountSpent: Money
@@ -3206,6 +3207,7 @@ input VoucherInput {
   minCheckoutItemsQuantity: Int
   countries: [String]
   applyOncePerOrder: Boolean
+  applyOncePerCustomer: Boolean
   usageLimit: Int
 }
 

saleor/order/emails.py

@@ -23,7 +23,7 @@ def collect_data_for_email(order_pk, template):
         template (str): email template path
     """
     order = Order.objects.get(pk=order_pk)
-    recipient_email = order.get_user_current_email()
+    recipient_email = order.get_customer_email()
     email_context = get_email_base_context()
     email_context["order_details_url"] = build_absolute_uri(
         reverse("order:details", kwargs={"token": order.token})