Setting up a CI/CD pipeline using Gitlab, Terraform and AWS

I recently setup a CI/CD pipeline using Gitlab Terraform and AWS. This post explains the various parts.

Gitlab Pipelines To setup a pipeline in Gitlab, you use a file called .gitlab-ci.yml.

The Gitlab pipeline file contents explained:

    default:
    image:
        name: hashicorp/terraform:latest
        entrypoint:
        - /usr/bin/env
        - "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"

    before_script:
        - terraform init
    cache:
        key: terraform
        paths:
        - .terraform

‘default’ sets up the standard used parts across the rest of the instructions ’entrypoint’ provides some basic commands to run automatically after the image starts

‘before_script’ runs before each script section

‘cache:paths’ choose which files or directorys to cache ‘cache:key’ gives each cache a key, so the cache can be re-used. Basically the way the cache is setup here, the terraform init command is run once and the output of that is used for future steps.

    stages:
    - stg_validate
    - stg_plan
    - stg_apply
    - stg_destroy


    jb-tf-validate:
    stage: stg_validate
    script:
    - echo " Validating my terraform code"
    - pwd
    - ls
    - terraform validate
    except:
        refs:
        - master
    jb-tf-plan:
    stage: stg_plan
    script:
        - echo "Generating terraform plan and output to file 'plan' "
        - terraform plan --out plan
    artifacts:
        paths:
        - plan

    jb-tf-apply:
    stage: stg_apply
    script:
        - echo "Spinning up resources via terraform apply step"
        - terraform apply --auto-approve plan
        - terraform state list
    when: always
    allow_failure: false
    artifacts:
        paths:
        - terraform.tfstate

    jb-tf-destroy:
    stage: stg_destroy
    script:
        - echo "Destroying resources"
        - terraform destroy --auto-approve
    when: manual
    only:
        refs:
        - develop

…more content coming soon..