Variable for branch name in GitHub Action

Question

When using GitHub Actions, is it possible to use a variable for the branch name?

I want to specify the branch name in on > push > branches, but I also want to use it later on in my job, so I am just trying to avoid duplication.

I am using this setup:

name: 'Build and deploy'

on:
  push:
    branches:
      - my-branch
  pull_request:
    branches:
      - my-branch
  workflow_dispatch:

env:
  GITHUB_BRANCH: 'my-branch'

Doing the following gets marked as an error:

on:
  push:
    branches:
      - ${{ env.GITHUB_BRANCH }} # Unrecognized named-value: env
  pull_request:
    branches:
      - ${{ env.GITHUB_BRANCH }} # Unrecognized named-value: env
  workflow_dispatch:

Is there a way to achieve this?

Answer 1

How about like this?

name: 'Build and deploy'

on:
  push:
    branches:
      - my-branch
  workflow_dispatch:

env:
  GITHUB_BRANCH: ${{ github.ref_name }}

That leaves the config in one place, so it reduces the duplication like you want. Instead of branches referencing the environment variable, the environment variable references the branch, but you still have the branch defined in just one place.