I'm working on setting up Terraform deployments using GitHub Actions, and I want to ensure my workflow remains clean and easy to maintain. Currently, I have a separate `.tfvars` file for each environment, organized by folders. I also collect information through a form, which includes details like network configuration that need to be incorporated into the respective `.tfvars` file before deployment. Is there an efficient way to update these files dynamically within a GitHub Actions workflow? Ideally, I want to automatically inject form data into the correct `.tfvars` file and then execute `terraform plan` and `terraform apply` for the selected environment. Any suggestions or examples would be greatly appreciated, especially regarding high-level architecture!
4 Answers
Consider asking AI for best practices, although be aware that sometimes the guidance isn't particularly hands-on. I found a lot of theoretical advice that didn’t translate well into practical implementations, especially concerning Terraform workflows with GitHub Actions.
If this is a personal project, I'd love to check out your repo! I've set up something similar for deploying resources on AWS using GitHub Actions. I have a two-job workflow: one for Plan and another for Apply, complete with manual approval steps. My credentials are stored securely in secrets, so that might be helpful for you!
You might want to check out Terragrunt! It’s designed to help manage regional and environment-specific variables without complicating things too much. Plus, it has its own GitHub Action and some helpful structural examples.
A common approach is to avoid modifying the `.tfvars` files directly in your pipeline. Instead, treat them as inputs during runtime and pass dynamic values from the workflow itself. Here's a simple setup for you:
1. Organize your environment into separate folders or use shared modules with a single set of `.tfvars` for each environment.
2. Collect your form data and store it in something like a GitHub environment secret, a JSON object in S3, or through a small API call.
3. In GitHub Actions, retrieve that data and provide it to Terraform using the `-var` or `-var-file` flags instead of altering the `.tfvars` file directly.
4. Select the correct environment folder based on your inputs.
5. Execute `terraform init`, `terraform plan`, and `terraform apply` with the appropriate `.tfvars` file plus any user-defined variables.
The key idea is to keep your environment `.tfvars` files stable and version-controlled without rewriting them during pipeline runs. Use temporary files for any dynamic information or pass values directly to maintain a clean and predictable workflow!
This makes so much sense! Thanks for laying it out step by step!
I get what you mean! I've done some digging as well, but practical examples seem scarce in that area.