The approach

We have already coded a feature for the myCafé application; now, we have been asked to publish this feature as a web API. Business thinks that other parties can build nice applications on top of it, and IT thinks that we can integrate the order subsystem as a microservice inside the company.

Note

If you are new to restful web API's design, you can get an introduction to it in RESTful Java Patterns and Best Practices, available at https://www.packtpub.com/application-development/restful-java-patterns-and-best-practices.

As an industry, it is a good practice to publish our logic as a REST service that follows the hypermedia approach. For this, we can use a standard mime type called application/hal+json; this is simply known as HAL.

Note

If you want to know the exact details of HAL, you could read the standard documentation at http://tools.ietf.org/html/draft-kelly-json-hal-06.

Basically, we need to create a web server that receives a GET HTTP request for the order, calls the display...