fix client compile error

_deploy/prod.Dockerfile

@@ -4,6 +4,8 @@ FROM node:current-alpine
 
 # Set environment variables for Node.js
 ENV NODE_ENV=production
+# ENV MYSQL_ROOT_PASSWORD=pass
+ENV MYSQL_DATABASE=cart
 
 # Create and set the working directory
 WORKDIR /app

components/availability/AvailabilityForm.js

@@ -25,7 +25,8 @@ export default function AvailabilityForm({ publisherId, existingItems, inline, o
     indexUrl: "/cart/availabilities"
   };
 
-  existingitems = existingitems || [];
+  //coalsce existingItems to empty array
+  existingItems = existingItems || [];
 
   const [editMode, setEditMode] = useState(existingItems.length > 0);
   const [publisher, setPublisher] = useState({ id: publisherId });