We started our chapter with understanding client software: how a software client works and how we can create a few. We saw the basics of writing a command-line application. CLI is a third-party package that enables us to create beautiful command-line applications. After installing it, we saw how to collect command-line arguments through the tool. We also explored commands and flags in our CLI application. Next, we looked into grequests, a package similar to Python requests to make API requests from Go code. We saw how to make GET, POST, and so on, requests from the client programs.

We next explored the GitHub API on how to fetch details like repositories. With the knowledge of both concepts, we developed a client that lists the repositories for a given user and also creates a gist (a text file on GitHub). We introduced Redis architecture on how caching could help handle rate-limited API. Finally, we wrote a unit test for the URL shortening service we created in the previous chapter.