Do you need to build an API? Are you paralyzed by the choices you need to make: What representation format to use, how to present errors, how to authenticate users? Will you be starting with a few endpoints, or many? Or gradually growing your API? Expressive is a middleware microframework that is incredibly suited to building APIs — particularly because we also provide packages for each of these API responsibilities.
In this tutorial, we will demonstrate buidling a REST API using Expressive. It will provide representations using Hypermedia Application Language, error handling in Problem Details for HTTP APIs format, authentication using OAuth2, and demonstrate common concerns such as data validation and authorization.