feat: Implement shipping_status most_expensive (viur-framework#135)

Author: sveneberth

src/viur/shop/modules/api.py

@@ -210,7 +210,7 @@ def cart_update(
         name: str = None,
         customer_comment: str = None,
         shipping_address_key: str | db.Key = None,
-        shipping_key: str | db.Key = None,
+        shipping_key: str | db.Key = SENTINEL,
         discount_key: str | db.Key = None,  # TODO: use sentinel?
         **kwargs,
     ):

src/viur/shop/skeletons/cart.py

@@ -154,15 +154,23 @@ def unserialize_compute(self, skel: "SkeletonInstance", name: str) -> bool:
         if skel["is_frozen"]:  # locked, unserialize the latest stored value from entity
             return False
 
-        if skel["shipping_status"] == ShippingStatus.CHEAPEST:  # compute cheapest
+        match skel["shipping_status"]:
+            case ShippingStatus.CHEAPEST:
+                func = min
+            case ShippingStatus.MOST_EXPENSIVE:
+                func = max
+            case _:
+                func = None
+
+        if func is not None:  # compute cheapest & most expensive
             self._prevent_compute = True
             try:
                 applicable_shippings = SHOP_INSTANCE.get().shipping.get_shipping_skels_for_cart(
                     cart_skel=skel, use_cache=True,
                 )
                 if applicable_shippings:
-                    cheapest_shipping = min(applicable_shippings,
-                                            key=lambda shipping: shipping["dest"]["shipping_cost"] or 0)
+                    cheapest_shipping = func(applicable_shippings,
+                                             key=lambda shipping: shipping["dest"]["shipping_cost"] or 0)
                     skel.setBoneValue("shipping", cheapest_shipping["dest"]["key"])
             finally:
                 self._prevent_compute = False
@@ -190,7 +198,7 @@ def _is_valid_user_shipping(self, skel: SkeletonInstance) -> bool:
             else:
                 logger.warning(f"Invalid shipping. {shipping_key=!r} not found in applicable_shippings")
                 skel.setBoneValue("shipping", None)
-                skel.setBoneValue("shipping_status", ShippingStatus.CHEAPEST)
+                skel.setBoneValue("shipping_status", skel.shipping_status.getDefaultValue())
                 return False
         finally:
             self._prevent_compute = False

src/viur/shop/types/enums.py

@@ -131,6 +131,9 @@ class ShippingStatus(enum.Enum):
     CHEAPEST = "cheapest"
     """Cheapest shipping selected"""
 
+    MOST_EXPENSIVE = "most_expensive"
+    """Most expensive shipping selected"""
+
 
 class VatRateCategory(enum.StrEnum):
     """Categorizes different VAT rate categories in the EU applied to goods and services."""