debian-mirror-gitlab/doc/user/infrastructure/index.md
2020-08-09 17:44:08 +05:30

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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
---
# 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
> [Introduced](https://gitlab.com/groups/gitlab-org/-/epics/2673) in GitLab 13.0.
[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).
## Permissions for using Terraform
In GitLab version 13.1, [Maintainer access](../permissions.md) was required to use a
GitLab managed Terraform state backend. In GitLab versions 13.2 and greater,
[Maintainer access](../permissions.md) is required to lock, unlock and write to the state
(using `terraform apply`), while [Developer access](../permissions.md) is required to read
the state (using `terraform plan -lock=false`).
## 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.
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:
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 which includes a
`gitlab-terraform` helper. For supported Terraform versions, see the [GitLab
Terraform Images project](https://gitlab.com/gitlab-org/terraform-images).
```yaml
image: registry.gitlab.com/gitlab-org/terraform-images/stable:latest
```
1. In the `.gitlab-ci.yaml` file, define some environment variables to ease
development. In this example, `TF_ROOT` is the directory where the Terraform
commands must be executed, `TF_ADDRESS` is the URL to the state on the GitLab
instance where this pipeline runs, and the final path segment in `TF_ADDRESS`
is the name of the Terraform state. Projects may have multiple states, and
this name is arbitrary, so in this example we will set it to the name of the
project, and we will ensure that the `.terraform` directory is cached between
jobs in the pipeline using a cache key based on the state name:
```yaml
variables:
TF_ROOT: ${CI_PROJECT_DIR}/environments/cloudflare/production
TF_ADDRESS: ${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/terraform/state/${CI_PROJECT_NAME}
cache:
key: ${CI_PROJECT_NAME}
paths:
- ${TF_ROOT}/.terraform
```
1. In a `before_script`, change to your `TF_ROOT`:
```yaml
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
```
1. Push your project to GitLab, which triggers a CI job pipeline. This pipeline
runs the `gitlab-terraform init`, `gitlab-terraform validate`, and
`gitlab-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. You can
either use a pre-built image which includes a `gitlab-terraform` helper as
above, where `gitlab-terraform plan-json` outputs the required artifact, or you
can configure this manually as follows:
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:
![Merge Request Terraform widget](img/terraform_plan_widget_v13_2.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: registry.gitlab.com/gitlab-org/terraform-images/stable:latest
variables:
TF_ROOT: ${CI_PROJECT_DIR}/environments/cloudflare/production
TF_ADDRESS: ${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/terraform/state/${CI_PROJECT_NAME}
cache:
key: ${CI_PROJECT_NAME}
paths:
- ${TF_ROOT}/.terraform
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 13.2, you can display mutiple reports on the Merge Request page. The reports will also display the `artifact: name:`. See example below for a suggested setup.
```yaml
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
```