Terraform Demo

A simple Terraform demo on GCP.

In a real life project, this code would sit in a folder within your project, perhaps under infra or similar.

For CI/CD, part of it could be triggered by (say) github action or similar.

Pre-requisites

Install Terraform locally. For Mac OS:

brew tap hashicorp/tap
brew install terraform
# update to latest version
brew update
brew upgrade hashicorp/tap/terraform

To verify is all good, try: terraform -help

A GCP service account terraform-runner with permissions: BigQuery Admin, Compute Admin & Storage Admin. Add its json key under under keys/terraform-runner-gcp.json.
- If you are running Terraform from your workstation, you can also use gcloud and authenticate using User Application Default Credentials ("ADCs") as a primary authentication method. You can enable ADCs using gcloud auth application-default login. See also Google provider configuration reference

If authenticating using service account, Terraform will need the path to service account json key:

# Path to service account json key (optional). 
GOOGLE_CREDENTIALS=keys/terraform-runner-gcp.json

run terraform init to get the GCP provider.

Development environment

The following assumes you are working locally to a development project.

Deploy new resources:

terraform plan. Check the plan - in particular the options and defaults of all resources to be created.
terraform apply. To deploy. A snapshot of the resources deployed will be stored in a terraform.tfstate local file.

Destroy resources

terraform destroy

Production environment

The terraform.tfstate file should be stored on cloud in a place that is secure but also accessible to those in your team with permission to deploy new infrastructure. This may also be a service account triggered by Github, for example. See also this guide for more examples.

Way of working

After every update to the Terraform code, ensure to format as terraform fmt.
Refer to the Terraform Registry for snippets of code; start here for GCP specific content.
Terraform provides snippets of code ready to copy and paste. It's worth:
- Checking with fields are actually required.
- Use terraform plan to double check the defaults are assigned to the properties of the resources.
variables and default (e.g. resource default region/zone) are defined in variables.tf and referred as var.VAR_NAME.
Using environmental variables: Terraform can directly access environment variables that are named using the pattern TF_VAR_. Otherwise, use the external data source.

SalvatoreMaraniello / terraform-demo