Is there a way in Terraform Enterprise to read the payload from VCS? - github

Question

I have configured a webhook between github and terraform enterprise correctly, so each time I push a commit, the terraform module gets executed. Why I want to achieve is to use part of the branch name where the push was made and pass it as a variable in the terraform module.
I have read that the value of a variable can be a HCL code, but I am unable to find the correct object to access the payload (or at least, the branch name), so at this moment I think it is not possible to get that value directly from the workspace configuration.
if you get a workaround for this, it may also work from me.
At this point the only idea I get is to call the terraform we hook using an API Call
Thanks in advance

Answer 1

Ok, after several try and error I found out that it is not possible to get any information in the terraform module if you are using the VCS mode. So, in order to be able to get the branch, I got these options:
Use several workspaces
You can configure a workspace for each branch, so you may create a variable a select that branch in each workspace. The problem is you will be repeating yourself with this option
Use Terraform CLI and a GitHub action
I used these fine tutorial from Hashicorp for creating a Github action that uses Terraform Cloud. It gets you done the 99% of the job. For passing a varible you must be aware that there are two methods, using a file or using an enviromental variable (check that information on the Hashicorp site here). So using a:
terraform apply -var="branch=value"
won't work. In my case I used the tfvars approach, so in my Github Action I put this snippet:
- name: Setup Terraform variables
id: vars
run: |-
cat > terraform.auto.tfvars <<EOF
branch = "${GITHUB_REF#refs/*/}"
EOF
I defined a variable within terraform called branch, I was able to get and work with this value