GitHub Actions GIT_BRANCH environment variable

Question

I have a GitHub action running my unit tests for a web app. I run CodeClimate test reporting from this action.

CodeClimate requires two environment variables to be set for the report to be correctly sent. These are;

• GIT_SHA
• GIT_BRANCH

GitHub actions makes the git commit sha avaiable through the github context via github.sha so I can set an environment variable on the action like this;

env:
    GIT_SHA: ${{ github.sha }}

However github actions does not make the branch name available.

It does provide a default environment variable called GITHUB_REF this is the full ref but I understand that I can grab the short ref i.e. the branch name using this shorthand syntax $GITHUB_REF##*/

The problem I have is that I cannot set an env variable called GITHUB_BRANCH with this value $GITHUB_REF##*/

Does anyone how I might get the branch name and set it to the environment variable GIT_BRANCH so the CodeClimate test script would be able to use it.

Ultimately I want my env config to look like this:

env:
    GIT_SHA: <git commit sha>
    GIT_BRANCH: <current git branch>

Answer 1

Ultimately I want my env config to look like this:

env:
   GIT_SHA: <git commit sha>
   GIT_BRANCH: <current git branch>

You can achieve the same effect (setting the environment variables) not only in the workflow definition but by setting the variables dynamically in a dedicated workflow step. You can do it by environment files and built-in GITHUB_SHA and GITHUB_BRANCH variables:

jobs:
  set-env:
    runs-on: ubuntu-latest
    steps:
      - name: Set environment variables
        run: |
          echo "GIT_SHA=${GITHUB_SHA}" >> $GITHUB_ENV
          echo "GIT_BRANCH=${GITHUB_REF##*/}" >> $GITHUB_ENV
      - name: Use environment variables
        run: |
          echo "GIT_SHA=${GIT_SHA}"
          echo "GIT_BRANCH=${GIT_BRANCH}"

Executing the workflow should give you the output: