Add checks for shipping information

src/storefront/cart.py

@@ -3,6 +3,8 @@ import logging
 from decimal import Decimal
 from django.conf import settings
 from django.contrib import messages
+from django.shortcuts import redirect, reverse
+from django.urls import reverse_lazy
 
 from core.models import Product, OrderLine, Coupon
 from core.usps import USPSApiWithRate
@@ -22,6 +24,7 @@ logger = logging.getLogger(__name__)
 
 class Cart:
     def __init__(self, request):
+        self.request = request
         self.session = request.session
         self.coupon_code = self.session.get('coupon_code')
         cart = self.session.get(settings.CART_SESSION_ID)
@@ -73,10 +76,12 @@ class Cart:
         return sum(item['quantity'] for item in self.cart.values())
 
     def get_total_weight(self):
-        return sum([item['product'].weight.value * item['quantity'] for item in self])
+        if len(self) > 0:
+            return sum([item['product'].weight.value * item['quantity'] for item in self])
+        else:
+            return 0
 
     def get_shipping_box(self):
-        logger.info(len(self))
         if len(self) > 6 and len(self) <= 10:
             return ShippingContainer.LG_FLAT_RATE_BOX
         elif len(self) > 2 and len(self) <= 6:
@@ -87,10 +92,19 @@ class Cart:
             return ShippingContainer.VARIABLE
 
     def get_shipping_cost(self):
-        usps_rate_request = self.build_usps_rate_request()
-        usps = USPSApiWithRate(settings.USPS_USER_ID, test=True)
-        validation = usps.get_rate(usps_rate_request)
-        return Decimal(validation.result['RateV4Response']['Package']['Postage']['CommercialRate'])
+        if len(self) > 0:
+            usps_rate_request = self.build_usps_rate_request()
+            usps = USPSApiWithRate(settings.USPS_USER_ID, test=True)
+            validation = usps.get_rate(usps_rate_request)
+            logger.info(validation.result)
+            try:
+                rate = Decimal(validation.result['RateV4Response']['Package']['Postage']['CommercialRate'])
+                return rate
+            except KeyError as e:
+                raise e("USPS Result has no 'Postage'")
+                return Decimal('0.00')
+        else:
+            return Decimal('0.00')
 
     def get_total_price(self):
         return sum(Decimal(item['price']) * item['quantity'] for item in self.cart.values())