Infrastructure as code with Terraform and GitLab

Motivation

The Terraform integration features within GitLab enable your GitOps / Infrastructure-as-Code (IaC) workflows to tie into GitLab's authentication and authorization. These features focus on lowering the barrier to entry for teams to adopt Terraform, collaborate effectively within GitLab, and support Terraform best practices.

GitLab Managed Terraform state

Terraform remote backends enable you to store the state file in a remote, shared store. GitLab uses the Terraform HTTP backend to securely store the state files in local storage (the default) or the remote store of your choice.

The GitLab managed Terraform state backend can store your Terraform state easily and securely, and spares you from setting up additional remote resources like Amazon S3 or Google Cloud Storage. Its features include:

Supporting encryption of the state file both in transit and at rest.
Locking and unlocking state.
Remote Terraform plan and apply execution.

Read more on setting up and using GitLab Managed Terraform states

Terraform integration in Merge Requests

Collaborating around Infrastructure as Code (IaC) changes requires both code changes and expected infrastructure changes to be checked and approved. GitLab provides a solution to help collaboration around Terraform code changes and their expected effects using the Merge Request pages. This way users don't have to build custom tools or rely on 3rd party solutions to streamline their IaC workflows.

Read more on setting up and using the merge request integrations.

Quick Start

Use the following .gitlab-ci.yml to set up a simple Terraform project integration for GitLab versions 13.5 and greater:

include:
  - template: Terraform.latest.gitlab-ci.yml

variables:
  # If not using GitLab's HTTP backend, remove this line and specify TF_HTTP_* variables
  TF_STATE_NAME: default
  TF_CACHE_KEY: default

This template uses .latest., instead of stable, and may include breaking changes. This template also includes some opinionated decisions, which you can override:

Including the latest GitLab Terraform Image.
Using the GitLab managed Terraform State as the Terraform state storage backend.
Creating four pipeline stages: init, validate, build, and deploy. These stages run the Terraform commands init, validate, plan, plan-json, and apply. The apply command only runs on master.