4 Deploying a Multi-Tiered Web Application in AWS

This chapter covers:

Packaging and organizing code in modules
Best practices for structuring complex projects using modules
Passing data between modules using input variables and output values
Downloading and utilizing modules from the module registry
Setting variable values from definition files

Don’t panic. The code in this chapter is a little crazy, I know, especially compared to what we’ve done before, but it’s not important that you completely understand it. Believe it or not, I actually want you to feel slightly uncomfortable, because that’s an important skill in being able to navigate someone else’s project structure and understand more or less how it works. The point of this chapter is not to teach you how to engineer a new project from scratch (as we’ll go over how to do that in the next chapter), but how to consume modules and pass data between them. That being said, you could pretty much lift this scenario as is, and with some minor tweaks, have a production ready system.

4.1 Motivation

4.2 Architecture Overview

4.3 Modules are Your Friend

4.3.1 Standard Module Structure

4.4 Root Module

4.5 Networking Module

4.6 Database Module

4.6.1 Passing Data from the Networking Module

4.6.2 Generating a Random Password

4.7 Autoscaling Module

4.7.1 Trickling Down Data

4.7.2 Detailed Module Planning

4.7.3 Getting Real with Template Files

4.7.4 Final Touches

4.8 Deploying the Webapp

4.9 Overview

4.10 Summary