tflint VS terragrunt

‍TFLint is a Terraform linter focused on possible errors, best practices, and style conventions in your Terraform code.

TFlint is a powerful linter for Terraform, designed to catch errors and issues that terraform plan may not detect. As Terraform grows in popularity for infrastructure as code, the need for robust tools to ensure code quality and reliability becomes paramount. TFlint fulfills this need by analyzing Terraform configurations to find problems that are not covered by syntax checks. It checks for things like unsuitable AWS instance types, incorrect IAM policy syntax, and the use of deprecated syntax or features. By integrating TFlint into the development process, users can proactively identify potential problems, improving the stability and efficiency of their infrastructure deployments. This additional layer of validation is crucial for maintaining high standards in complex, cloud-based infrastructures.

Looking at the description, https://github.com/terraform-linters/tflint , I think it's not what I am looking for. The reason I used a different tcp port is to make the health check on load balancer fail. It's also the same as not changing the tcp port but developer making a code change in their javascript, nodejs, java, etc fail to start properly. If that happens, load balancer's health check will fail as well.

TFLint is an open-source infrastructure as code linter tool that helps developers and DevOps teams identify potential issues and errors in their Terraform code by checking the Terraform configuration files for best practices, coding standards, and policy compliance.

Indeed, that is the case, atm. Your comment got me searching a little bit more. It seems that they are planning to implement a flag for small fixes https://github.com/terraform-linters/tflint/issues/266

Sounds like tflint to me!

I created a .tflint.hcl with the following content: https://github.com/terraform-linters/tflint/blob/master/docs/user-guide/config.md (The example)

TFLint: This is a Terraform linter that checks for errors and best practices in your Terraform code. TFLint helps to catch common mistakes, such as variable name clashes, missing required variables, or invalid resource arguments. It also checks for compliance with best practices, such as naming conventions and resource ordering. By using TFLint, you can catch errors early on, which helps to improve the quality of your Terraform code.

tflint: Linter para Terraform, serve para avisar sobre problemas com sintaxe, erros nos principais provedores de nuvem, garantir boas práticas e outras coisas.

name: Configure on: push: branches: - main pull_request: branches: - main workflow_dispatch: inputs: destroy: description: 'Run Terragrunt destroy command' required: true default: 'false' type: choice options: - true - false jobs: apply: if: ${{ !inputs.destroy || inputs.destroy == 'false' }} runs-on: ubuntu-latest steps: - name: Checkout repository uses: actions/checkout@v2 - name: Setup SSH uses: webfactory/[email protected] with: ssh-private-key: ${{ secrets.SSH_PRIVATE_KEY }} - name: Setup Terraform uses: hashicorp/setup-terraform@v2 with: terraform_version: 1.5.5 terraform_wrapper: false - name: Setup Terragrunt run: | curl -LO "https://github.com/gruntwork-io/terragrunt/releases/download/v0.48.1/terragrunt_linux_amd64" chmod +x terragrunt_linux_amd64 sudo mv terragrunt_linux_amd64 /usr/local/bin/terragrunt terragrunt -v - name: Apply Terraform changes run: | cd dev terragrunt run-all apply -auto-approve --terragrunt-non-interactive -var AWS_ACCESS_KEY_ID=$AWS_ACCESS_KEY_ID -var AWS_SECRET_ACCESS_KEY=$AWS_SECRET_ACCESS_KEY -var AWS_REGION=$AWS_DEFAULT_REGION env: AWS_ACCESS_KEY_ID: ${{ vars.AWS_ACCESS_KEY_ID }} AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }} AWS_DEFAULT_REGION: ${{ vars.AWS_DEFAULT_REGION }} destroy: if: ${{ inputs.destroy == 'true' }} runs-on: ubuntu-latest steps: - name: Checkout repository uses: actions/checkout@v2 - name: Setup SSH uses: webfactory/[email protected] with: ssh-private-key: ${{ secrets.SSH_PRIVATE_KEY }} - name: Setup Terraform uses: hashicorp/setup-terraform@v2 with: terraform_version: 1.5.5 terraform_wrapper: false - name: Setup Terragrunt run: | curl -LO "https://github.com/gruntwork-io/terragrunt/releases/download/v0.48.1/terragrunt_linux_amd64" chmod +x terragrunt_linux_amd64 sudo mv terragrunt_linux_amd64 /usr/local/bin/terragrunt terragrunt -v - name: Destroy Terraform changes run: | cd dev terragrunt run-all destroy -auto-approve --terragrunt-non-interactive -var AWS_ACCESS_KEY_ID=$AWS_ACCESS_KEY_ID -var AWS_SECRET_ACCESS_KEY=$AWS_SECRET_ACCESS_KEY -var AWS_REGION=$AWS_DEFAULT_REGION env: AWS_ACCESS_KEY_ID: ${{ vars.AWS_ACCESS_KEY_ID }} AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }} AWS_DEFAULT_REGION: ${{ vars.AWS_DEFAULT_REGION }}

‍Terragrunt is a thin wrapper that provides extra tools for keeping your Terraform configurations DRY (Don't Repeat Yourself), working with multiple Terraform modules, and managing remote state. It's particularly useful in managing large-scale infrastructure deployments with Terraform.

... #************************** Terraform ************************************* ARG TERRAFORM_VERSION=1.7.3 RUN set -ex \ && curl -O https://releases.hashicorp.com/terraform/${TERRAFORM_VERSION}/terraform_${TERRAFORM_VERSION}_linux_amd64.zip && unzip terraform_${TERRAFORM_VERSION}_linux_amd64.zip -d /usr/local/bin/ RUN set -ex \ && mkdir -p $HOME/.terraform.d/plugin-cache && echo 'plugin_cache_dir = "$HOME/.terraform.d/plugin-cache"' > ~/.terraformrc #************************* Terragrunt ************************************* ARG TERRAGRUNT_VERSION=0.55.1 RUN set -ex \ && wget https://github.com/gruntwork-io/terragrunt/releases/download/v${TERRAGRUNT_VERSION}/terragrunt_linux_amd64 -q \ && mv terragrunt_linux_amd64 /usr/local/bin/terragrunt \ && chmod +x /usr/local/bin/terragrunt #*********************** Terramate **************************************** ARG TERRAMATE_VERSION=0.4.5 RUN set -ex \ && wget https://github.com/mineiros-io/terramate/releases/download/v${TERRAMATE_VERSION}/terramate_${TERRAMATE_VERSION}_linux_x86_64.tar.gz \ && tar -xzf terramate_${TERRAMATE_VERSION}_linux_x86_64.tar.gz \ && mv terramate /usr/local/bin/terramate \ && chmod +x /usr/local/bin/terramate #*********************** tfsec ******************************************** ARG TFSEC_VERSION=1.28.5 RUN set -ex \ && wget https://github.com/aquasecurity/tfsec/releases/download/v${TFSEC_VERSION}/tfsec-linux-amd64 \ && mv tfsec-linux-amd64 /usr/local/bin/tfsec \ && chmod +x /usr/local/bin/tfsec \ && terragrunt --version #**********************Terraform docs ************************************ ARG TERRRAFORM_DOCS_VERSION=0.17.0 RUN set -ex \ && curl -sSLo ./terraform-docs.tar.gz https://terraform-docs.io/dl/v${TERRRAFORM_DOCS_VERSION}/terraform-docs-v${TERRRAFORM_DOCS_VERSION}-$(uname)-amd64.tar.gz \ && tar -xzf terraform-docs.tar.gz \ && chmod +x terraform-docs \ && mv terraform-docs /usr/local/bin/terraform-docs #********************* ShellCheck ***************************************** ARG SHELLCHECK_VERSION="stable" RUN set -ex \ && wget -qO- "https://github.com/koalaman/shellcheck/releases/download/${SHELLCHECK_VERSION?}/shellcheck-${SHELLCHECK_VERSION?}.linux.x86_64.tar.xz" | tar -xJv \ && cp "shellcheck-${SHELLCHECK_VERSION}/shellcheck" /usr/bin/ \ && shellcheck --version ...

Our first attempt was to introduce other engineering teams to Terraform - the Platform team was already using it extensively with Terragrunt, and using Atlantis to automate plan and apply operations in a Git flow to ensure infrastructure was consistent. We'd written modules, with documentation, and an engineer would simply need to raise a PR to use the module and provide the right values, and Atlantis (once the PR was approved by Platform) would go ahead and set it up for them.

Terragrunt: An extension of Terraform, Terragrunt assists in managing complex infrastructure with less duplication and more efficiency. Its power lies in its ability to manage dependencies and its dry configuration approach.

Copy the link and download on your terminal using the wget command. Example: wget https://github.com/gruntwork-io/terragrunt/releases/download/v0.54.19/terragrunt_linux_amd64

name: Configure on: push: branches: - main pull_request: branches: - main jobs: terraform: runs-on: ubuntu-latest steps: - name: Checkout repository uses: actions/checkout@v2 - name: Setup SSH uses: webfactory/[email protected] with: ssh-private-key: ${{ secrets.SSH_PRIVATE_KEY }} - name: Setup Terraform uses: hashicorp/setup-terraform@v2 with: terraform_version: 1.5.5 terraform_wrapper: false - name: Setup Terragrunt run: | curl -LO "https://github.com/gruntwork-io/terragrunt/releases/download/v0.48.1/terragrunt_linux_amd64" chmod +x terragrunt_linux_amd64 sudo mv terragrunt_linux_amd64 /usr/local/bin/terragrunt terragrunt -v - name: Apply Terraform changes run: | cd dev terragrunt run-all apply -auto-approve --terragrunt-non-interactive -var AWS_ACCESS_KEY_ID=$AWS_ACCESS_KEY_ID -var AWS_SECRET_ACCESS_KEY=$AWS_SECRET_ACCESS_KEY -var AWS_REGION=$AWS_DEFAULT_REGION cd apache-server/ec2-web-server public_ip=$(terragrunt output instance_public_ip) echo "$public_ip" > public_ip.txt cat public_ip.txt env: AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }} AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }} AWS_DEFAULT_REGION: ${{ secrets.AWS_DEFAULT_REGION }} - name: Upload artifact uses: actions/upload-artifact@v4 with: name: ip-artifact path: dev/apache-server/ec2-web-server/public_ip.txt ansible: runs-on: ubuntu-latest needs: terraform steps: - name: Download artifact uses: actions/download-artifact@v4 with: name: ip-artifact - name: Configure Ansible run: | sudo apt update sudo pipx inject ansible-core jmespath ansible-playbook --version sudo echo "[web]" >> ansible_hosts sudo cat public_ip.txt >> ansible_hosts mv ansible_hosts $HOME sudo cat $HOME/ansible_hosts - name: Configure playbook run: | cd $HOME cat > deploy.yml < Test Page This is a test page EOF cat $HOME/deploy.yml - name: Run playbook uses: dawidd6/action-ansible-playbook@v2 with: playbook: deploy.yml directory: /home/runner key: ${{secrets.SSH_PRIVATE_KEY}} options: | --inventory ansible_hosts --verbose

Created and maintained by Gruntwork, Terragrunt is a tool designed to enhance Terraform’s capabilities. It acts as a thin wrapper around Terraform, offering additional features to streamline and optimise Terraform usage. Key functions of Terragrunt include helping users keep their Terraform configurations DRY (Don’t Repeat Yourself), efficiently managing multiple Terraform modules, and handling remote state management. By reducing repetition in Terraform code and simplifying the management of complex module dependencies and remote state, Terragrunt makes working with Terraform more efficient, especially for larger or more complex infrastructure deployments.

locals { # Automatically load region-level variables region_vars = read_terragrunt_config(find_in_parent_folders("region.hcl")) # Automatically load environment-level variables` environment_vars = read_terragrunt_config(find_in_parent_folders("env.hcl")) # Extract the variables we need for easy access account_name = local.environment_vars.locals.account_name account_id = local.environment_vars.locals.aws_account_id aws_region = local.region_vars.locals.aws_region # This is the S3 bucket where the Terraform State Files will be stored remote_state_bucket = "devops-bucket" # This is the DynamoDB table where Terraform will add the locking status dynamodb_table = "terraform-state-lock" # IAM Role for Terraform backend to assume terraform_backend_role = "arn:aws:iam::{shared-services_account_id}:role/terraform-backend-role" environment_path = replace(path_relative_to_include(), "environments/", "") # https://github.com/hashicorp/terraform/releases terraform_version = "latest" # https://github.com/gruntwork-io/terragrunt/releases terragrunt_version = "latest" } # Generate an AWS provider block generate "provider" { path = "provider.tf" if_exists = "overwrite_terragrunt" contents = <

If your team works with Terraform, you should definitely try Terragrunt (and obviously, its CLI tool!). It's an Infrastructure as Code (IaC) tool that acts as a wrapper for Terraform and simplifies dealing with multiple Terraform modules in different environments.