Without data, you can't query for data 🤔
You can add data source resolvers to your GraphQL API in the AWS console, but in this lesson, we'll be doing it all in our CDK app. This is in adherence with the infrastructure as code best practice.
We'll create a lambda function entirely within our CDK app. We'll create a data source with our AppSync GraphQL API and add our lambda function as the handler. Then we have to make sure that data-source is invoked when there is a query to listBooks