Terraform at Scale

Chapter 5. Developing Modules

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In software development, a common point of discussion is around scopes and contexts. They shape how we organize, protect, and reuse code—reducing ambiguity and minimizing friction during development, execution, and maintenance.

Up to this point, we’ve focused on two primary scopes in TF: expressions and blocks. Many times, these are indeed the important scopes to consider. However, there is another major scope: the module.

In TF, everything is encapsulated within a module, so at all times, you are developing a module in some fashion. It could be oriented around a number of different aspects of a software project including the cloud services that host and service your application stack as well as the applications themselves.

In this chapter, you’ll see different types of modules and how they may be used strategically to create effective TF projects that follow the shape of your organization. You will learn how to develop effective modules for use by other members ...