This GitHub Action will expose the slug/short values of some GitHub environment variables inside your GitHub workflow.

SLUG on a variable will

• put the variable content in lower case
• replace any character by - except 0-9, a-z, ., and _
• remove leading - characters
• limit the string size to 63 characters
• remove trailing - characters

• SLUG_URL on a variable to have a slug variable compliant to be used in a URL
  • Like SLUG but ., and _ are also replaced by -
• SHORT on a variable will limit the string size to ~8 characters
  • Useful for sha value
• <KEY>_PART on a variable will give a part of a variable defined by a key
  • Like GITHUB_REPOSITORY_OWNER_PART for the owner part of GITHUB_REPOSITORY
• <VAR>_CS on others variables to keep the value case-sensitive
  • Like GITHUB_REF_SLUG_CS

Add this step to your workflow

steps:
  - name: Inject enhanced GitHub environment variables
    uses: rlespinasse/github-slug-action@v5

steps:
  - name: Inject enhanced GitHub environment variables
    uses: rlespinasse/github-slug-action@v5
    with:
      prefix: CI_

steps:
  - name: Inject enhanced GitHub environment variables
    uses: rlespinasse/github-slug-action@v5
    with:
      slug-maxlength: 80 # Use 'nolimit' to remove use of a max length (Default to 63)

steps:
  - name: Inject enhanced GitHub environment variables
    uses: rlespinasse/github-slug-action@v5
    with:
      short-length: 7 # By default it's up to Git to decide, use 8 to have the v3.x behaviour

The length of a short sha depends of the size of your repository and can differ over time :

• set 7 to keep the small repository behaviour,
• set 8 to reproduce v3 behaviour,
• set 4 as the minimum length possible.

• GITHUB_REF_POINT will contains the reference name (branch or tag)
  • based on GITHUB_HEAD_REF in a pull-request* event context,
  • based on GITHUB_REF_NAME in others event context.

Same as slug variables but URL-compliant

The GITHUB_REF_NAME SLUG/SLUG_URL variables doesn't work the same way as before

Before v5, the behaviour was the same as the GitHub one except on pull_request* workflows (Ready the full story).

• ${{ env.GITHUB_REF_NAME }} will serve the behaviour of this action,
• $GITHUB_REF_NAME will serve the behaviour of GitHub Action.

On pull_request* workflows, the content will be <PR-number>/merge instead of the branch name. So you need to use GITHUB_REF_POINT instead

steps:
  - name: Inject enhanced GitHub environment variables
    uses: rlespinasse/github-slug-action@v5
  - run: |
      echo "Branch Name: ${GITHUB_REF_POINT}"
    shell: bash

Then ${{ env.GITHUB_REF_POINT }}, and $GITHUB_REF_POINT will serve the behaviour of this action. And ${{ env.GITHUB_REF_NAME }}, and $GITHUB_REF_NAME will serve the behaviour of GitHub Action.

Since v4, it's Git who manage the short variables by using git rev-parse behaviour. The length of a short sha depends of the size of your repository and can differ over time.

To manage that moving length, you can use short-length input

• set 7 to reproduce small repository behaviour
• set 8 to reproduce v3 behaviour

So to reproduce previous behaviour, use

steps:
  - name: Inject enhanced GitHub environment variables
    uses: rlespinasse/github-slug-action@v5
    with:
      short-length: 8 # Same as v3 and before

If a variable start to be used as default environment variable, the environment variable may have a different behaviour than the expected one.

If this append, the ${{ env.GITHUB_AWESOME_VARIABLE }} and $GITHUB_AWESOME_VARIABLE expression will not works in the same way.

• ${{ env.GITHUB_AWESOME_VARIABLE }} will serve the behaviour of this action,
• $GITHUB_AWESOME_VARIABLE will serve the behaviour of GitHub Action.

Otherwise the two expression will serve the behaviour of this action. This will not occurs if you use the prefix input to avoid the issue.

If your workflow fail on the Set up job task with this kind of log

Download action repository 'rlespinasse/github-slug-action@GIT_REFERENCE'
##[error]An action could not be found at the URI 'https://api.github.com/repos/rlespinasse/github-slug-action/tarball/GIT_REFERENCE'

If the GIT_REFERENCE value is

• v4.x or after, the branch don't exists anymore following the end-of-life for a branch security process.
• master, the branch don't exists anymore, read more about it on the corresponding issue (EOL issue)

Please, use the current major tag v5 or a version tag (see releases pages) in order to fix your workflow.

In English 🇬🇧

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In French 🇫🇷

• Mettre en place une CI/CD Angular avec GitHub Actions & Netlify
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In Chinese 🇨🇳

• 利用github-slug-action暴漏GitHub Action上下文中的关键变量

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