This repository is for the GitHub Action to run a Super-Linter. It is a simple combination of various linters, written in bash, to help validate your source code.

The end goal of this tool:

• Prevent broken code from being uploaded to the default branch (Usually master or main)
• Help establish coding best practices across multiple languages
• Build guidelines for code layout and format
• Automate the process to help streamline code reviews

• Super-Linter
  • Table of Contents
  • How it Works
  • Supported Linters
  • How to use
    • Example connecting GitHub Action Workflow
    • Add Super-Linter badge in your repository README
    • Images
      • Standard Image
      • Slim Image
  • Environment variables
    • Template rules files
    • Using your own rules files
    • Disabling rules
    • Using your own SSH key
  • Filter linted files
  • Docker Hub
  • Run Super-Linter outside GitHub Actions
    • Local (troubleshooting/debugging/enhancements)
    • Azure
    • GitLab
    • Codespaces and Visual Studio Code
    • SSL Certs
  • Limitations
  • How to contribute
    • License

The super-linter finds issues and reports them to the console output. Fixes are suggested in the console output but not automatically fixed, and a status check will show up as failed on the pull request.

The design of the Super-Linter is currently to allow linting to occur in GitHub Actions as a part of continuous integration occurring on pull requests as the commits get pushed. It works best when commits are being pushed early and often to a branch with an open or draft pull request. There is some desire to move this closer to local development for faster feedback on linting errors but this is not yet supported.

Developers on GitHub can call the GitHub Action to lint their codebase with the following list of linters:

More in-depth tutorial available

To use this GitHub Action you will need to complete the following:

1. Create a new file in your repository called .github/workflows/linter.yml
2. Copy the example workflow from below into that new file, no extra configuration required
3. Commit that file to a new branch
4. Open up a pull request and observe the action working
5. Enjoy your more stable, and cleaner codebase
6. Check out the Wiki for customization options

NOTE: If you pass the Environment variable GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }} in your workflow, then the GitHub Super-Linter will mark the status of each individual linter run in the Checks section of a pull request. Without this you will only see the overall status of the full run. There is no need to set the GitHub Secret as it is automatically set by GitHub, it only needs to be passed to the action.

In your repository you should have a .github/workflows folder with GitHub Action similar to below:

• .github/workflows/linter.yml
  • Example file can be found at TEMPLATES/linter.yml

This file should have the following code:

---
#################################
#################################
## Super Linter GitHub Actions ##
#################################
#################################
name: Lint Code Base

#############################
# Start the job on all push #
#############################
on:
  push:
    branches-ignore: [master, main]
    # Remove the line above to run when pushing to master
  pull_request:
    branches: [master, main]

###############
# Set the Job #
###############
jobs:
  build:
    # Name the Job
    name: Lint Code Base
    # Set the agent to run on
    runs-on: ubuntu-latest

    ##################
    # Load all steps #
    ##################
    steps:
      ##########################
      # Checkout the code base #
      ##########################
      - name: Checkout Code
        uses: actions/checkout@v3
        with:
          # Full git history is needed to get a proper
          # list of changed files within `super-linter`
          fetch-depth: 0

      ################################
      # Run Linter against code base #
      ################################
      - name: Lint Code Base
        uses: github/super-linter@v4
        env:
          VALIDATE_ALL_CODEBASE: false
          DEFAULT_BRANCH: master
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

You can show Super-Linter status with a badge in your repository README

Format:

[![GitHub Super-Linter](https://github.com/<OWNER>/<REPOSITORY>/workflows/Lint%20Code%20Base/badge.svg)](https://github.com/marketplace/actions/super-linter)

Example:

[![GitHub Super-Linter](https://github.com/nvuillam/npm-groovy-lint/workflows/Lint%20Code%20Base/badge.svg)](https://github.com/marketplace/actions/super-linter)

Note: IF you did not use Lint Code Base as GitHub Action name, please read GitHub Actions Badges documentation.

The GitHub Super-Linter now builds and supports multiple images. We have found as we added more linters, the image size expanded drastically. After further investigation, we were able to see that a few linters were very disk heavy. We removed those linters and created the slim image. This allows users to choose which Super-Linter they want to run and potentially speed up their build time. The available images:

• github/super-linter:v4
• github/super-linter:slim-v4

The standard github/super-linter:v4 comes with all supported linters. Example usage:

################################
# Run Linter against code base #
################################
- name: Lint Code Base
  uses: github/super-linter@v4
  env:
    VALIDATE_ALL_CODEBASE: false
    DEFAULT_BRANCH: master
    GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

The slim github/super-linter:slim-v4 comes with all supported linters but removes the following:

• rust linters
• dotenv linters
• armttk linters
• pwsh linters
• c# linters

By removing these linters, we were able to bring the image size down by 2gb and drastically speed up the build and download time. The behavior will be the same for non-supported languages, and will skip languages at run time. Example usage:

################################
# Run Linter against code base #
################################
- name: Lint Code Base
  uses: github/super-linter/slim@v4
  env:
    VALIDATE_ALL_CODEBASE: false
    DEFAULT_BRANCH: master
    GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

The super-linter allows you to pass the following ENV variables to be able to trigger different functionality.

Note: All the VALIDATE_[LANGUAGE] variables behave in a very specific way:

• If none of them are passed, then they all default to true.
• If any one of the variables are set to true, we default to leaving any unset variable to false (only validate those languages).
• If any one of the variables are set to false, we default to leaving any unset variable to true (only exclude those languages).
• If there are VALIDATE_[LANGUAGE] variables set to both true and false. It will fail.

This means that if you run the linter "out of the box", all languages will be checked. But if you wish to select or exclude specific linters, we give you full control to choose which linters are run, and won't run anything unexpected.

You can use the GitHub Super-Linter with or without your own personal rules sets. This allows for greater flexibility for each individual codebase. The Template rules all try to follow the standards we believe should be enabled at the basic level.

• Copy any or all template rules files from TEMPLATES/ into the .github/linters/ directory of your repository, and modify them to suit your needs.
  • The rules files in this repository's TEMPLATE folder will be used as defaults should any be omitted.

If your repository contains your own rules files that live outside of a .github/linters/ directory, you will have to tell Super-Linter where your rules files are located in your repository, and what their filenames are. To learn more, see Using your own rules files.

If you need to disable certain rules and functionality, you can view Disable Rules

If you need to add your own SSH key to the linter because of private dependencies, you can use the SSH_KEY environment variable. The value of that environment variable should be an SSH private key that has access to your private repositories.

You should add this key as an Encrypted Secret and access it with the secrets parameter.

Example workflow:

---
#################################
#################################
## Super Linter GitHub Actions ##
#################################
#################################
name: Lint Code Base

#############################
# Start the job on all push #
#############################
on:
  push:
    branches-ignore: [master, main]
    # Remove the line above to run when pushing to master
  pull_request:
    branches: [master, main]

###############
# Set the Job #
###############
jobs:
  build:
    # Name the Job
    name: Lint Code Base
    # Set the agent to run on
    runs-on: ubuntu-latest

    ##################
    # Load all steps #
    ##################
    steps:
      ##########################
      # Checkout the code base #
      ##########################
      - name: Checkout Code
        uses: actions/checkout@v3
        with:
          # Full git history is needed to get a proper list of changed files within `super-linter`
          fetch-depth: 0

      ################################
      # Run Linter against code base #
      ################################
      - name: Lint Code Base
        uses: github/super-linter@v4
        env:
          VALIDATE_ALL_CODEBASE: false
          DEFAULT_BRANCH: master
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          SSH_KEY: ${{ secrets.SSH_PRIVATE_KEY }}

If you need to lint only a folder or exclude some files from linting, you can use optional environment parameters FILTER_REGEX_INCLUDE and FILTER_REGEX_EXCLUDE

Examples:

• Lint only src folder: FILTER_REGEX_INCLUDE: .*src/.*
• Do not lint files inside test folder: FILTER_REGEX_EXCLUDE: .*test/.*
• Do not lint JavaScript files inside test folder: FILTER_REGEX_EXCLUDE: .*test/.*.js

Additionally when IGNORE_GENERATED_FILES=true, super-linter ignores any file with @generated marker in it unless the file also has @not-generated marker. @generated marker is used by Facebook and some other projects to mark generated files. For example, this file is considered generated:

#!/bin/sh
echo "@generated"

And this file is considered not generated:

#!/bin/sh
echo "@generated" # @not-generated

The Docker container that is built from this repository is located at github/super-linter

If you find that you need to run super-linter locally, you can follow the documentation at Running super-linter locally

Check out the note in How it Works to understand more about the Super-Linter linting locally versus via continuous integration.

Check out this article

Check out this snippet and this Guided Exploration: GitLab CI CD Extension for Super-Linter

You can checkout this repository using GitHub Codespaces and Container Remote Development, and debug the linter using the Test Linter task.

If you need to inject a SSL cert into the trust store, you will need to first copy the cert to GitHub Secrets Once you have copied the plain text certificate into GitHub Secrets, you can use the variable SSL_CERT_SECRET to point the Super-Linter to the files contents. Once found, it will load the certificate contents to a file, and to the trust store.

• Example workflow:

- name: Lint Code Base
  uses: github/super-linter@v4
  env:
    GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
    SSL_CERT_SECRET: ${{ secrets.ROOT_CA }}

Below are a list of the known limitations for the GitHub Super-Linter:

• Due to being completely packaged at runtime, you will not be able to update dependencies or change versions of the enclosed linters and binaries
• Additional details from package.json are not read by the GitHub Super-Linter
• Downloading additional codebases as dependencies from private repositories will fail due to lack of permissions

If you would like to help contribute to this GitHub Action, please see CONTRIBUTING

• MIT License