Infrastructure as Code, 2nd Edition

Chapter 9. Testing Infrastructure Stacks

This chapter applies the core practice of continuously testing and delivering code to infrastructure stacks. It uses the ShopSpinner example to illustrate how to test a stack project. This includes using online and offline test stages and making use of test fixtures to decouple the stack from dependencies.

Example Infrastructure

The ShopSpinner team uses reusable stack projects (see “Pattern: Reusable Stack”) to create consistent instances of application infrastructure for each of its customers. It can also use this to create test instances of the infrastructure in the pipeline.

The infrastructure for these examples is a standard three-tier system. The infrastructure in each tier consists of:

Web server container cluster

The team runs a single web server container cluster for each region and in each test environment. Applications in the region or environment share this cluster. The examples in this chapter focus on the infrastructure that is specific to each customer, rather than shared infrastructure. So the shared cluster is a dependency in the examples here. For details of how changes are coordinated and tested across this infrastructure, see Chapter 17.

Application server

The infrastructure for each application instance includes a virtual machine, a persistent disk volume, and networking. The networking includes an address block, gateway, routes to the server on its network port, and network access rules.

Database

ShopSpinner ...