debian-mirror-gitlab/doc/user/infrastructure/index.md

---
stage: Configure
group: Configure
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#designated-technical-writers
---

# Infrastructure as code with Terraform and GitLab

## GitLab managed Terraform State

[Terraform remote backends](https://www.terraform.io/docs/backends/index.html)
enable you to store the state file in a remote, shared store. GitLab uses the
[Terraform HTTP backend](https://www.terraform.io/docs/backends/types/http.html)
to securely store the state files in local storage (the default) or
[the remote store of your choice](../../administration/terraform_state.md).

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.

To get started with a GitLab-managed Terraform State, there are two different options:

- [Use a local machine](#get-started-using-local-development).
- [Use GitLab CI](#get-started-using-gitlab-ci).

## Get started using local development

If you plan to only run `terraform plan` and `terraform apply` commands from your
local machine, this is a simple way to get started:

1. Create your project on your GitLab instance.
1. Navigate to **{settings}** **Settings > General** and note your **Project name**
   and **Project ID**.
1. Define the Terraform backend in your Terraform project to be:

   ```hcl
   terraform {
     backend "http" {
     }
   }
   ```

1. Create a [Personal Access Token](../profile/personal_access_tokens.md) with
   the `api` scope. The Terraform backend is restricted to users with
   [Maintainer access](../permissions.md) to the repository.

1. On your local machine, run `terraform init`, passing in the following options,
   replacing `<YOUR-PROJECT-NAME>`, `<YOUR-PROJECT-ID>`,  `<YOUR-USERNAME>` and
   `<YOUR-ACCESS-TOKEN>` with the relevant values. This command initializes your
   Terraform state, and stores that state within your GitLab project. This example
   uses `gitlab.com`:

   ```shell
   terraform init \
       -backend-config="address=https://gitlab.com/api/v4/projects/<YOUR-PROJECT-ID>/terraform/state/<YOUR-PROJECT-NAME>" \
       -backend-config="lock_address=https://gitlab.com/api/v4/projects/<YOUR-PROJECT-ID>/terraform/state/<YOUR-PROJECT-NAME>/lock" \
       -backend-config="unlock_address=https://gitlab.com/api/v4/projects/<YOUR-PROJECT-ID>/terraform/state/<YOUR-PROJECT-NAME>/lock" \
       -backend-config="username=<YOUR-USERNAME>" \
       -backend-config="password=<YOUR-ACCESS-TOKEN>" \
       -backend-config="lock_method=POST" \
       -backend-config="unlock_method=DELETE" \
       -backend-config="retry_wait_min=5"
   ```

Next, [configure the backend](#configure-the-backend).

## Get started using GitLab CI

If you don't want to start with local development, you can also use GitLab CI to
run your `terraform plan` and `terraform apply` commands.

Next, [configure the backend](#configure-the-backend).

## Configure the backend

After executing the `terraform init` command, you must configure the Terraform backend
and the CI YAML file:

CAUTION: **Important:**
The Terraform backend is restricted to users with [Maintainer access](../permissions.md)
to the repository.

1. In your Terraform project, define the [HTTP backend](https://www.terraform.io/docs/backends/types/http.html)
   by adding the following code block in a `.tf` file (such as `backend.tf`) to
   define the remote backend:

   ```hcl
   terraform {
     backend "http" {
     }
   }
   ```

1. In the root directory of your project repository, configure a `.gitlab-ci.yaml` file.
   This example uses a pre-built image:

   ```yaml
   image:
     name: hashicorp/terraform:light
     entrypoint:
       - '/usr/bin/env'
       - 'PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin'
   ```

1. In the `.gitlab-ci.yaml` file, define some environment variables to ease development. In this
   example, `GITLAB_TF_ADDRESS` is the URL of the GitLab instance where this pipeline
   runs, and `TF_ROOT` is the directory where the Terraform commands must be executed:

   ```yaml
   variables:
     GITLAB_TF_ADDRESS: ${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/terraform/state/${CI_PROJECT_NAME}
     TF_ROOT: ${CI_PROJECT_DIR}/environments/cloudflare/production

   cache:
     paths:
       - .terraform
   ```

1. In a `before_script`, pass a `terraform init` call containing configuration parameters
   corresponding to variables required by the
   [HTTP backend](https://www.terraform.io/docs/backends/types/http.html):

   ```yaml
   before_script:
     - cd ${TF_ROOT}
     - terraform --version
     - terraform init -backend-config="address=${GITLAB_TF_ADDRESS}" -backend-config="lock_address=${GITLAB_TF_ADDRESS}/lock" -backend-config="unlock_address=${GITLAB_TF_ADDRESS}/lock" -backend-config="username=gitlab-ci-token" -backend-config="password=${CI_JOB_TOKEN}" -backend-config="lock_method=POST" -backend-config="unlock_method=DELETE" -backend-config="retry_wait_min=5"

   stages:
     - validate
     - build
     - test
     - deploy

   validate:
     stage: validate
     script:
       - terraform validate

   plan:
     stage: build
     script:
       - terraform plan
       - terraform show

   apply:
     stage: deploy
     environment:
       name: production
     script:
       - terraform apply
     dependencies:
       - plan
     when: manual
     only:
       - master
   ```

1. Push your project to GitLab, which triggers a CI job pipeline. This pipeline runs
   the `terraform init`, `terraform validate`, and `terraform plan` commands.

The output from the above `terraform` commands should be viewable in the job logs.

## Example project

See [this reference project](https://gitlab.com/nicholasklick/gitlab-terraform-aws) using GitLab and Terraform to deploy a basic AWS EC2 within a custom VPC.

## Output Terraform Plan information into a merge request

Using the [GitLab Terraform Report artifact](../../ci/pipelines/job_artifacts.md#artifactsreportsterraform),
you can expose details from `terraform plan` runs directly into a merge request widget,
enabling you to see statistics about the resources that Terraform will create,
modify, or destroy.

Let's explore how to configure a GitLab Terraform Report artifact:

1. For simplicity, let's define a few reusable variables to allow us to
   refer to these files multiple times:

   ```yaml
   variables:
     PLAN: plan.tfplan
     PLAN_JSON: tfplan.json
   ```

1. Install `jq`, a
   [lightweight and flexible command-line JSON processor](https://stedolan.github.io/jq/).
1. Create an alias for a specific `jq` command that parses out the information we
   want to extract from the `terraform plan` output:

   ```yaml
   before_script:
     - apk --no-cache add jq
     - alias convert_report="jq -r '([.resource_changes[]?.change.actions?]|flatten)|{\"create\":(map(select(.==\"create\"))|length),\"update\":(map(select(.==\"update\"))|length),\"delete\":(map(select(.==\"delete\"))|length)}'"
   ```

1. Define a `script` that runs `terraform plan` and `terraform show`. These commands
   pipe the output and convert the relevant bits into a store variable `PLAN_JSON`.
   This JSON is used to create a
   [GitLab Terraform Report artifact](../../ci/pipelines/job_artifacts.md#artifactsreportsterraform).
   The Terraform report obtains a Terraform `tfplan.json` file. The collected
   Terraform plan report is uploaded to GitLab as an artifact, and is shown in merge requests.

   ```yaml
   plan:
     stage: build
     script:
       - terraform plan -out=$PLAN
       - terraform show --json $PLAN | convert_report > $PLAN_JSON
     artifacts:
       name: plan
       paths:
         - $PLAN
       reports:
         terraform: $PLAN_JSON
   ```

   For a full example, see [Example `.gitlab-ci.yaml` file](#example-gitlab-ciyaml-file).

1. Running the pipeline displays the widget in the merge request, like this:

   ![MR Terraform widget](img/terraform_plan_widget_v13_0.png)

1. Clicking the **View Full Log** button in the widget takes you directly to the
   plan output present in the pipeline logs:

   ![Terraform plan logs](img/terraform_plan_log_v13_0.png)

### Example `.gitlab-ci.yaml` file

```yaml
image:
  name: hashicorp/terraform:light
  entrypoint:
    - '/usr/bin/env'
    - 'PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin'

# Default output file for Terraform plan
variables:
  GITLAB_TF_ADDRESS: ${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/terraform/state/${CI_PROJECT_NAME}
  PLAN: plan.tfplan
  PLAN_JSON: tfplan.json
  TF_ROOT: ${CI_PROJECT_DIR}

cache:
  paths:
    - .terraform

before_script:
  - apk --no-cache add jq
  - alias convert_report="jq -r '([.resource_changes[]?.change.actions?]|flatten)|{\"create\":(map(select(.==\"create\"))|length),\"update\":(map(select(.==\"update\"))|length),\"delete\":(map(select(.==\"delete\"))|length)}'"
  - cd ${TF_ROOT}
  - terraform --version
  - terraform init -backend-config="address=${GITLAB_TF_ADDRESS}" -backend-config="lock_address=${GITLAB_TF_ADDRESS}/lock" -backend-config="unlock_address=${GITLAB_TF_ADDRESS}/lock" -backend-config="username=${GITLAB_USER_LOGIN}" -backend-config="password=${GITLAB_TF_PASSWORD}" -backend-config="lock_method=POST" -backend-config="unlock_method=DELETE" -backend-config="retry_wait_min=5"

stages:
  - validate
  - build
  - deploy

validate:
  stage: validate
  script:
    - terraform validate

plan:
  stage: build
  script:
    - terraform plan -out=$PLAN
    - terraform show --json $PLAN | convert_report > $PLAN_JSON
  artifacts:
    name: plan
    paths:
      - ${TF_ROOT}/plan.tfplan
    reports:
      terraform: ${TF_ROOT}/tfplan.json

# Separate apply job for manual launching Terraform as it can be destructive
# action.
apply:
  stage: deploy
  environment:
    name: production
  script:
    - terraform apply -input=false $PLAN
  dependencies:
    - plan
  when: manual
  only:
    - master

```