HashiCorp Terraform is an infrastructure-as-code (IaC) tool that lets you provision and manage cloud infrastructure. Terraform provides plugins calledproviders that let you interact with cloud providers and other APIs. You can use theTerraform provider for Google Cloud to provision and manage Google Cloud resources, including Compute Engine.

This page introduces you to using Terraform with Compute Engine, including an introduction to how Terraform works and some resources to help you get started using Terraform with Google Cloud. You'll also find links to Terraform reference docs for Compute Engine, code examples, and guides for using Terraform to provision Compute Engine resources.

For instructions on how to get started with Terraform for Google Cloud, seeInstall and configure Terraform or theTerraform for Google Cloud quickstart.

How Terraform works

Terraform has a declarative and configuration-oriented syntax, which you can use to describe the infrastructure that you want to provision in your Google Cloud project. After you author this configuration in one or more Terraform configuration files, you can use the Terraform CLI to apply this configuration to your Compute Engine resources.

The following steps explain how Terraform works:

1. You describe the infrastructure you want to provision in aTerraform configuration file. You don't need to write code describing how to provision the infrastructure. Terraform provisions the infrastructure for you.
2. You run theterraform plan command, which evaluates your configuration and generates an execution plan. You can review the plan and make changes as needed.

3. You run theterraform apply command, which performs the following actions:

   1. It provisions your infrastructure based on your execution plan by invoking the corresponding Compute Engine APIs in the background.
   2. It creates aTerraform state file, which is a JSON file that maps the resources in your configuration file to the resources in the real-world infrastructure. Terraform uses this file to keep a record of the most recent state of your infrastructure, and to determine when to create, update, and destroy resources.

   3. When you runterraform apply, Terraform uses the mapping in the state file to compare the existing infrastructure to the code, and make updates as necessary:

      • If a resource object is defined in the configuration file, but doesn't exist in the state file, Terraform creates it.
      • If a resource object exists in the state file, but has a different configuration from your configuration file, Terraform updates the resource to match your configuration file.
      • If a resource object in the state file matches your configuration file, Terraform leaves the resource unchanged.

Terraform resources for Compute Engine

Resources are the fundamental elements in the Terraform language. Eachresource block describes one or more infrastructure objects, such as virtualnetworks or compute instances.

The following table lists the Terraform resources available forCompute Engine:

Terraform-based guides for Compute Engine

The following table lists Terraform-based how-to guides and tutorials for Compute Engine:

Terraform modules and blueprints for Compute Engine

Modules and blueprints help you automate provisioning and managing of Google Cloud resources at scale. Amodule is a reusable set of Terraform configuration files that creates a logical abstraction of Terraform resources. Ablueprint is a package of deployable and reusable modules, and a policy that implements and documents a specific solution.

The following table lists modules and blueprints related to Compute Engine:

What's next

• Terraform code samples for Compute Engine
• Terraform on Google Cloud documentation
• Google Cloud provider documentation in HashiCorp
• Infrastructure as code for Google Cloud