Terraform at Scale

Chapter 3. Effective Use of Logic

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TF is a platform that abstracts the APIs of service providers and other platforms. Although the Hashicorp Configuration Language (HCL), the language in which TF code is written, is primarily a configuration language, there are logic expressions available in HCL allowing developers to introduce inferences and abstractions, improving the flexibility (or general accessibility) of a solution, without introducing repetitive code or requiring deep technical knowledge on behalf of a module’s consumer. However, there is a well-established tendency to see all the world’s problems as a collection of nails once one has mastered the hammer, and this can lead a team into a quagmire of configuration as all complexity is shoved into HCL, regardless of the means. At the same time, a draconian adherence to a set of traditional, sacrosanct HCL expressions can force teams into developing unreasonably large and repetitive codebase or into splitting a team’s overall state into ...