GitLab File Variable Usage with Dot or Period in Name: Troubleshooting and Workarounds

When working within a GitLab CI pipeline, encountering issues when trying to use file variables that include dot ( .) notation can be common. The standard naming conventions for these environment variable keys restrict characters allowed – only letters (a-z, A-Z), digits (0-9), and underscores _ are permitted according to the GitLab documentation:

Variables key must contain alphanumeric or _ symbols, hyphens (-) may not be used. Special chars should percent encode (%24 for $)…

If you have a file named .auto.tfvars, here’s how to correctly handle this within your CI job using GitLab:

1. Define the Environment Variable in the project settings under “Variables”:

   MYGITLAB_FILEVARIABLE=contents  # 'contents' holds a placeholder for file content or path reference here
   

2. In your .gitlab-ci.yml configuration, add steps to copy this variable into the desired location:

stages:
  - prepare_env

variables: []
before_script:
  script:
    - mkdir /secure/location # Replace with actual secure directory where your .tfvars file should go. Ensure it's writable by CI runners or relevant roles on the system for this to work correctly.

prepare-tfvar:
  stage: prepare_env
  only: []
  variables: [MYGITLAB_FILEVARIABLE] # Retrieve your environment variable here in script context.
  script:
    - cp $MYGITLAB_FILEVARIABLE /secure/location/$CI_PIPELINE_ID-$MYGITLAB_FILEVARIABLE-copy # Use the actual file reference to copy it into a designated secure location on your system for Terraform usage in later stages.

The $ symbol indicates variable substitution within scripts and must be prefixed when referencing environment variables provided by GitLab CI/CD configuration settings from .gitlab-ci.yml. The before_script section helps to define the directory structure where your file should reside for further processing in subsequent stages of pipeline execution, such as deploying Terraform configurations with proper variable assignments that are essential for infrastructure provisioning tasks within GitLab CI/CD workflows.

Remember to replace /secure/location/ and $CI_PIPELINE_ID placeholders used above according to your actual environment configuration settings required by the pipeline process, while ensuring they conform with security best practices relevant in a production or sensitive development setup where Terraform infrastructure definitions are managed.