juush / bd-serialization

Serializing and deserializing Order objects

You have a database table, OnlineUserOrders, that keeps track of users' online orders and the cost of each order.

First, use CloudFormation to populate the table.

1. Create the tables we'll be using for this activity by running the following aws CLI commands:

   aws cloudformation create-stack --region us-west-2 --stack-name dynamodbscan-onlineuserorderstable --template-body file://cloudformation/DynamoDB_OnlineUserOrders.yml --capabilities CAPABILITY_IAM
   

2. Make sure the aws command runs without error.
3. Log into your AWS account and verify that the table exists in DynamoDB and has sample data.

The OnlineUserOrders table looks like this:

• userId: partition key—unique id for each user
• orderId: sort key—unique id for each order
• totalCost: total cost of the order

You want to be able to transfer data from the table so that it can be stored in a file and backed up. You also need to be able to recover from one of these backup files by deserializing each order object and writing it to the database. You will be implementing the methods on the OrderSerializer class. The toJSON method accepts an Order object and returns its JSON representation, and the toOrder accepts a String and returns an Order object.

You have also been provided with a OrderSerializationException that can be thrown if an exception occurs while serializing or deserializing.