Blog-Technical-Content VS terraform-docs

We will set up a GitHub repository with a simple Terraform file that deploys an EC2 instance on AWS. You can find the demo contents here.

Next, we will go through an example of creating a custom module that takes as input a string that represents an epoch timestamp and converts it to its human-readable equivalent of type datetime in Python. You can find the code for this tutorial on this repository.

This is an example play to try out our new webserver role. Let’s go ahead and execute this play. To follow along, you should first run the vagrant up command from the top directory of this repository to create our target remote host.

Let’s examine how we can use all this in a real-world example. In this GitHub repository, we define the Terraform configuration for this example’s infrastructure. To follow along, you will need to install Terraform, have an AWS account ready, and authenticate with your AWS keys via the command line. Note that you might be charged a few dollars in your AWS account if you follow along.

If you are still learning how to use Ansible, you might also find helpful the introductory Ansible Tutorial or Working with Ansible Playbooks blog posts. You can find this article’s code on this repository if you wish to follow along.

Our primary entry point is main.tf, and in simple use cases, we can add all our resources there. We define our variables in variables.tf and assign values to them in terraform.tfvars. We use the file outputs.tf to declare output values. You can find a similar example project structure here.

Documentation is really important, so having a README.md file inside your Terraform repository that explains how to use the automation (including descriptions of variables and outputs) really help in understanding what has been implemented. To easily generate the description of variables and outputs, you can leverage tfdocs.

‍Terraform-docs is a tool that automatically generates documentation from Terraform modules in various output formats, including markdown, JSON, and others. It's particularly useful for maintaining up-to-date documentation of your Terraform modules' inputs, outputs, providers, and resources.

Earlier this year I wrote about the challenges I faced creating a Terraform module. I mentioned then that I was leveraging terraform-docs and GitHub Actions to automate documentation, but a full workflow walkthrough was out of that post's scope.

### Muti-Stage pipeline for windows trigger: - main variables: terraformDocsVersion: '0.16.0' serviceConnectionName: 'Terraform-SPN-DevOps-MagiconionM' keyvaultName: 'pwd9000-core-kv' pool: vmImage: 'windows-latest' stages: - stage: GenerateTerraformDocumentation jobs: - job: Generate_Terraform_Documentation steps: - checkout: self persistCredentials: true # this allows the later scripts to use the system-provided git token to push changes back to the repo ### Link to key vault. - task: AzureKeyVault@1 inputs: azureSubscription: $(serviceConnectionName) #ADO service connection (Service principal) KeyVaultName: $(keyvaultName) SecretsFilter: 'TerraformDocsPAToken' RunAsPreJob: true displayName: Get PAToken from Keyvault ### Install Terraform-Docs. - powershell: | Invoke-WebRequest -Uri "https://github.com/terraform-docs/terraform-docs/releases/download/v$(terraformDocsVersion)/terraform-docs-v$(terraformDocsVersion)-windows-amd64.zip" -OutFile "terraform-docs.zip" Expand-Archive -Path "terraform-docs.zip" -DestinationPath "$(System.DefaultWorkingDirectory)\terraform-docs" -Force $env:Path += ";$(System.DefaultWorkingDirectory)\terraform-docs" displayName: 'Install terraform-docs' ### Remove all old README.md files and generate new README.md files for each TF module. - powershell: | # Set Modules Root Directory Set-Location "$(Build.SourcesDirectory)\@TF_Modules" # Get all subdirectories (Terraform module directories) $terraformModuleDirs = Get-ChildItem -Path (Get-Location) -Directory # Loop through each directory to cleanup/remove old README files foreach ($dir in $terraformModuleDirs) { # Get all files in the directory $readMeFiles = Get-ChildItem -Path $dir.FullName -Filter 'README.md' # Loop through each file in each terraform module foreach ($file in $readMeFiles) { # Check if README file already exists and remove if ($file) { # Remove the file Remove-Item $file.FullName -Confirm:$false Write-Output "Old file '$($file.Name)' removed from '$($dir.FullName)'" } } #After cleanup create a new README.md file with 'terraform-docs' based on latest TF module code in current folder(terraform module) $tfFiles = Get-ChildItem -Path $dir.FullName -Filter *.tf if ($tfFiles.Count -gt 0) { # Create new README.md file $(System.DefaultWorkingDirectory)\terraform-docs\terraform-docs.exe markdown table $dir.FullName --output-file "README.md" } else { Write-Output "No .tf files found." } } displayName: 'Cleanup and Generate new README for each TF module' ### Commit and push updated README.md files for TF modules. - powershell: | git config --local user.email "[email protected]" git config --local user.name "Terraform Docs" git add *.md git commit -m "Update README.md for each TF module" git push origin HEAD:$(Build.SourceBranchName) displayName: 'Commit and Push updated README.md files for TF modules' env: SYSTEM_ACCESSTOKEN: $(TerraformDocsPAToken)

I'm going to have to figure out how to run terraform-docs.io against each module. I have zero terraform experience.

Terraform-docs: This tool generates documentation for your Terraform modules in various formats, such as Markdown, HTML, and JSON. Terraform-docs parses your Terraform code and extracts documentation from comments, variable and output descriptions, and input/output examples. The tool then generates a table of contents with links to the relevant documentation for each module, which makes it easy to understand the purpose and usage of each module.

Terraform docs

I have been using https://terraform-docs.io to generate documentation of my terraform modules. However creating nested objects with optionals makes the documentation rather ugly and hard to read. See gh issue which also describes this type of issue: https://github.com/terraform-docs/terraform-docs/issues/656

I am looking for a way to automate doc creation and updates for ansible roles. I recently discovered terraform-docs and I am curious if there is something similar for ansible.

terraform-docs: https://github.com/terraform-docs/terraform-docs

Do you have other Terraform-related open-source tools that you recommend? Please go ahead and add in the comments!