Infrastructure as Code with Terraform

Programme overview

Infrastructure as code is how serious teams change their cloud: written in files, reviewed in pull requests, applied by a pipeline. In this course you take over Tallybook's Terraform estate. You'll learn HCL and the init, plan and apply workflow by running real Terraform in Colab with providers that need no cloud account. Then, working from Tallybook's state file, variable files and the plans of six pull requests in the exact JSON format Terraform produces, you'll find the half of its servers Terraform doesn't manage, the database passwords sitting in plain text in state, a 'rename' that would destroy the production database, a firewall change opening the database to the internet and a major upgrade hidden in an innocent-looking PR. You'll write policy checks that block the dangerous plans automatically, detect drift against the real cloud inventory, and design the modules and pipeline that make Terraform the only way infrastructure changes.

Curriculum

1. 01Why Infrastructure as Code15 min

   • Why infrastructure as codeWhat infrastructure as code is and the problems it solves, how Terraform records what it manages, and how much of Tallybook's cloud was created by hand and forgotten.
2. 02Providers, Resources and the Workflow25 min

   • Providers, resources and the workflowRead and write Terraform's language (HCL) - providers, resources, arguments and references - and learn the init, plan and apply workflow by running real Terraform in Colab with providers that need no cloud account.
3. 03Variables and Environments25 min

   • Variables and environmentsUse variables, variable files, locals and outputs so one set of code builds both staging and production, and compare the two environments to see where they differ and what each costs.
4. 04State and Secrets25 min

   • State and secretsUnderstand what Terraform's state file contains, why it must be stored remotely with locking and encryption, and find the secrets sitting in plain text inside Tallybook's state.
5. 05Reading a Plan25 min

   • Reading a planRead a Terraform plan, both as people see it and as the JSON that tools read, summarise what each change will create, update, replace or destroy, and do it for six real pull requests.
6. 06Dangerous Changes25 min

   • Dangerous changesRecognise the plans that destroy data or cause downtime (replacements of stateful resources, renames, mass deletions and hidden attribute changes) and fix them with moved blocks, lifecycle rules and safer sequencing.
7. 07Policy as Code25 min

   • Policy as codeTurn review rules into automatic checks that run on every plan (no destroying stateful resources, no sensitive ports open to the internet, required tags, flagged major upgrades) and see which of Tallybook's pull requests they block.
8. 08Drift and Imports25 min

   • Drift and importsFind drift (real infrastructure that no longer matches Terraform's state) and resources Terraform doesn't manage, then decide for each whether to import it, change it back or delete it.
9. 09Modules and the Pipeline20 min

   • Modules and the pipelinePackage repeated infrastructure as modules with pinned versions, and design the pull request pipeline (format, validate, plan, policy checks, review and apply) that turns everything in this course into the everyday way of working.
10. 10Final Project20 min

    • Final project: Tallybook's infrastructure reviewPlan your final project, a review of Tallybook's Terraform estate and six pending pull requests, with policy checks, drift and secrets findings, and the plan to make Terraform the only way infrastructure changes.

Assessment and certificate

You are assessed with a final assessment (pass mark 60%) and a final project. Your certificate is awarded when you meet those requirements. Paying for the programme does not award it on its own.