Wrapping a client in added functionality and function composition

In 2015, Tomás Senart gave an excellent talk on wrapping an http.Client struct 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 takes from his ideas and demonstrates an example of doing the same to the Transport interface of the http.Client struct similar to our earlier recipe, Writing a client for a REST API.

This recipe will implement a logging and basic auth middleware for a standard http.Client struct. It also includes a decorate function that can be used when you need to with a large variety of middleware.

Getting ready

Refer to the Getting ready section of the Initializing, storing, and passing http.Client structs recipe in this chapter.

How to do it...

These steps cover writing and running your application:

1. From your terminal/console application, create the chapter6/decorator directory and navigate...