[frontend] fix item calculation and shipping (#2684)

Author: julianocosta89

CHANGELOG.md

@@ -18,6 +18,8 @@ the release.
 * [chore] Upgrade OpenFeature and add fix deprecation warnings for dependency
   injection
   ([#2644](https://github.com/open-telemetry/opentelemetry-demo/pull/2644))
+* [frontend] fix item calculation and shipping
+  ([#2684](https://github.com/open-telemetry/opentelemetry-demo/pull/2684))
 
 ## 2.1.3
 

src/frontend/pages/cart/checkout/[orderId]/index.tsx

@@ -21,10 +21,10 @@ const Checkout: NextPage = () => {
   const { orderId, items = [], shippingAddress, shippingCost = { units: 0, currencyCode: 'USD', nanos: 0 } } = JSON.parse((query.order || '{}') as string) as IProductCheckout;
 
   const orderTotal = useMemo<Money>(() => {
-    const itemsTotal = items.reduce((acc, { cost = { units: 0, nanos: 0, currencyCode: 'USD' } }) => {
+    const itemsTotal = items.reduce((acc, { item, cost = { units: 0, nanos: 0, currencyCode: 'USD' } }) => {
       return {
-        units: acc.units + (cost.units || 0),
-        nanos: acc.nanos + (cost.nanos || 0),
+        units: acc.units + (cost.units || 0) * item.quantity,
+        nanos: acc.nanos + (cost.nanos || 0) * item.quantity,
         currencyCode: cost.currencyCode || 'USD',
       };
     }, { units: 0, nanos: 0, currencyCode: 'USD' });

src/quote/app/routes.php

@@ -26,7 +26,7 @@ function calculateQuote($jsonObject): float
             throw new \InvalidArgumentException('numberOfItems not provided');
         }
         $numberOfItems = intval($jsonObject['numberOfItems']);
-        $costPerItem = rand(400, 1000)/10;
+        $costPerItem = 8.99;
         $quote = round($costPerItem * $numberOfItems, 2);
 
         $childSpan->setAttribute('app.quote.items.count', $numberOfItems);