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---
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
---
# 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.
## 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 creates,
modifies, or destroys.
## Setup
NOTE: **Note:**
GitLab ships with a [pre-built CI template](index.md#quick-start) that uses GitLab Managed Terraform state and integrates Terraform changes into merge requests. We recommend customizing the pre-built image and relying on the `gitlab-terraform` helper provided within for a quick setup.
To manually configure a GitLab Terraform Report artifact requires the following steps:
1. For simplicity, let's define a few reusable variables to allow us to
refer to these files multiple times:
```yaml
variables:
PLAN: plan.cache
PLAN_JSON: plan.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)}'"
```
NOTE: **Note:**
In distributions that use Bash (for example, Ubuntu), `alias` statements are not
expanded in non-interactive mode. If your pipelines fail with the error
`convert_report: command not found`, alias expansion can be activated explicitly
by adding a `shopt` command to your script:
```yaml
before_script:
- shopt -s expand_aliases
- 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:
reports:
terraform: $PLAN_JSON
```
For a full example using the pre-built image, see [Example `.gitlab-ci.yaml`
file](#example-gitlab-ciyaml-file).
For an example displaying multiple reports, see [`.gitlab-ci.yaml` multiple reports file](#multiple-terraform-plan-reports).
1. Running the pipeline displays the widget in the merge request, like this:
1. Clicking the **View Full Log** button in the widget takes you directly to the
plan output present in the pipeline logs:
### Example `.gitlab-ci.yaml` file
```yaml
default:
image: registry.gitlab.com/gitlab-org/terraform-images/stable:latest
cache:
key: example-production
paths:
- ${TF_ROOT}/.terraform
variables:
TF_ROOT: ${CI_PROJECT_DIR}/environments/example/production
TF_ADDRESS: ${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/terraform/state/example-production
before_script:
- cd ${TF_ROOT}
stages:
- prepare
- validate
- build
- deploy
init:
stage: prepare
script:
- gitlab-terraform init
validate:
stage: validate
script:
- gitlab-terraform validate
plan:
stage: build
script:
- gitlab-terraform plan
- gitlab-terraform plan-json
artifacts:
name: plan
paths:
- ${TF_ROOT}/plan.cache
reports:
terraform: ${TF_ROOT}/plan.json
apply:
stage: deploy
environment:
name: production
script:
- gitlab-terraform apply
dependencies:
- plan
when: manual
only:
- master
```
### Multiple Terraform Plan reports
Starting with GitLab version 13.2, you can display multiple reports on the Merge Request
page. The reports also display the `artifacts: name:`. See example below for a suggested setup.
```yaml
default:
image:
name: registry.gitlab.com/gitlab-org/gitlab-build-images:terraform
entrypoint:
- '/usr/bin/env'
- 'PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin'
cache:
paths:
- .terraform
stages:
- build
.terraform-plan-generation:
stage: build
variables:
PLAN: plan.tfplan
JSON_PLAN_FILE: tfplan.json
before_script:
- cd ${TERRAFORM_DIRECTORY}
- terraform --version
- terraform init
- apk --no-cache add jq
script:
- terraform validate
- terraform plan -out=${PLAN}
- terraform show --json ${PLAN} | jq -r '([.resource_changes[]?.change.actions?]|flatten)|{"create":(map(select(.=="create"))|length),"update":(map(select(.=="update"))|length),"delete":(map(select(.=="delete"))|length)}' > ${JSON_PLAN_FILE}
artifacts:
reports:
terraform: ${TERRAFORM_DIRECTORY}/${JSON_PLAN_FILE}
review_plan:
extends: .terraform-plan-generation
variables:
TERRAFORM_DIRECTORY: "review/"
# Review will not include an artifact name
staging_plan:
extends: .terraform-plan-generation
variables:
TERRAFORM_DIRECTORY: "staging/"
artifacts:
name: Staging
production_plan:
extends: .terraform-plan-generation
variables:
TERRAFORM_DIRECTORY: "production/"
artifacts:
name: Production
```
|
