License Check Action

A GitHub Action that validates source code files contain proper license and copyright headers.

Description

This composite action scans the repository for source code files and verifies that each file contains either a "Copyright" statement or "Apache License" reference in its header. This helps ensure compliance with open-source licensing requirements.

Usage

- name: Check License Headers
  uses: ./.github/actions/license-check-action

Example Workflow

name: License Compliance

on:
  pull_request:
  push:
    branches:
      - main

jobs:
  license-check:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Run license check
        uses: ./.github/actions/license-check-action

How It Works

The action performs the following steps:

1. Recursively finds all files in the repository (excluding .git directory)
2. Filters files based on extension and name patterns
3. Searches each file for the text "Copyright" or "Apache License"
4. Reports any files missing the required license header
5. Fails the check if any violations are found

Excluded File Types

The following file types and patterns are automatically excluded from license checking:

Binary and Media Files

• Images: .png, .jpg, .gif, .ico, .svg, .PNG
• Fonts: .eot, .ttf, .woff
• Documents: .pdf, .docx, .graffle
• Archives: .tar, .tar.gz, .jar, .oar, .csar

Configuration and Data Files

• .json, .jsonld, .JSON
• .xml, .yaml, .yml, .toml
• .properties, .conf, .cfg, .cnf, .config
• .csv, .db, .log
• .txt, .md, .rst

Certificate and Key Files

• .pem, .crt, .cert, .key, .csr, .der
• .jks, .p12, .asc, .gpg

Generated and Build Files

• .pb.go, .pb.gw.go, *_pb2.py, *_pb2_grpc.py
• .pb.h, .pb.cc
• .pyc, .bin
• go.mod, go.sum
• .lock files

Special Files

• Dockerfile, Dockerfile.*
• Makefile, Makefile.*
• README
• *ignore files (e.g., .gitignore, .dockerignore)
• *rc files (e.g., .bashrc, .npmrc)

Excluded Directories

• vendor/
• conf/
• git/
• swagger/
• docs/

Troubleshooting

False Positives

If files are incorrectly flagged as missing license headers:

1. Verify the file contains either "Copyright" or "Apache License" text
2. Check that the text appears in a comment format appropriate for the file type
3. Ensure there are no encoding issues preventing text detection