Summary

In this chapter, we've covered how to import and export raw CSV data in our application, how to extend the functionality of our applications by including external libraries with Ruby gems, and how to interact with the filesystem using Ruby.

These are powerful tools that can turn our applications from toys into real services with just a few simple lines of code. With these new tools, we can import data from databases, spreadsheets, or any number of other sources and process them programmatically with Ruby in any way we want; the options are endless.

We've also learned some best practices regarding how to structure code that doesn't necessarily fit within our domain models by refactoring them into service objects, keeping our models lean and clean. Your coworkers will thank you for this one, trust me.

An application is only as good as its input and output. We've now learned a few methods by which we can increase how much we input by importing external...