config.js

const HEADERLENGTHMAX = 50;
const LINELENGTHMAX = 72;
const BODYLENGTHMIN = 15;

module.exports = {
  parserPreset: './.commitlint-parser-preset',
  rules: {

    // Body
    'body-leading-blank':   [2, 'always'],                // blank line between header and body
    'body-empty':           [2, 'never'],                 // body cannot be empty
    'body-max-line-length': [2, 'always', LINELENGTHMAX], // body lines max chars LINELENGTHMAX
    'body-min-length' :     [2, 'always', BODYLENGTHMIN], // body more than BODYLENGTHMIN chars

    // Footer
    'footer-leading-blank':   [2, 'always'],                // blank line between body and footer
    'footer-max-line-length': [2, 'always', LINELENGTHMAX], // footer lines max chars LINELENGTHMAX

    // Header
    'header-case':       [2, 'always', 'lower-case'],    // header lower case
    'header-max-length': [2, 'always', HEADERLENGTHMAX], // header max chars HEADERLENGTHMAX

    // Scope
    'scope-empty': [2, 'never'], // scope always
    'scope-enum': [
      2,
      'always',
      [
        'front', // Front-End change
        'back',  // Back-End change
        'infra', // Infrastructure change
        'conf',  // Configuration files change
        'build', // System component change (ci, scons, webpack...)
        'job',   // asynchronous or schedule tasks (backups, maintainance...)
        'cross', // Mix of two or more scopes
        'doc',   // Documentation only changes
      ],
    ],

    // Subject (commit title without type and scope)
    'subject-case':  [2, 'always', 'lower-case'], // subject lower-case
    'subject-empty': [2, 'never'],                // subject always

    // Type
    'type-empty': [2, 'never'], //type always
    'type-enum': [
      2,
      'always',
      [
        'feat',  // New feature
        'perf',  // Improves performance
        'fix',   // Bug fix
        'rever', // Revert to a previous commit in history
        'style', // Do not affect the meaning of the code (formatting, etc)
        'refac', // Neither fixes a bug or adds a feature
        'test',  // Adding missing tests or correcting existing tests
      ],
    ],
  },
};