Resolving Environment Variable Case Sensitivity Issues in GitHub Actions

When working with GitHub Actions workflows that use environment variables from organization or repository secrets, it's important to maintain consistent casing between your variable references and the actual secret names. Common Issues If you receive errors about missing environment variables in your workflow, even though you've defined them as secrets, check the following: Verify that your secrets are properly set at either the repository or organization level (Settings → Secrets and variables → Actions) Ensure the casing in your workflow matches exactly with your secret names (e.g., DUPLO_TOKEN should not be referenced as duplo_token) Correct Implementation When mapping secrets to environment variables in your workflow, use the following format: env: DUPLO_TOKEN: ${{ secrets.DUPLO_TOKEN }} DUPLO_HOST: ${{ vars.DUPLO_HOST }} Important: GitHub Actions treats variables with different casing as distinct variables. Having both uppercase and lowercase versions of the same variable name can cause errors in your workflow. Best Practices Use consistent uppercase naming for environment variables and secrets Always map organization/repository secrets to environment variables explicitly in your workflow Double-check the casing when referencing secrets or variables in your workflows