In 2015, Tomás Senart gave an excellent talk on wrapping an http.Client structure with an interface, allowing you to take advantage of middleware and function composition. You can find out more on this at https://github.com/gophercon/2015-talks. This recipe borrows from his ideas and demonstrates an example of performing the same action on the Transport interface of the http.Client structure, in a similar way to our earlier recipe, Writing a client for a REST API.

The following recipe will implement logging and basic auth middleware for a standard http.Client structure. It also includes a decorate function that can be used when required with a large variety of middleware.