Environment-based configuration for JavaScript applications - Gulpfile.js

Gulpfile.js

var Gulp        = require('gulp');
var Del         = require('del');
var Rename      = require('gulp-rename');
var RunSequence = require('run-sequence');
var Yargs       = require('yargs');

var argv = Yargs.argv;

/**
 * Build Settings
 */
var settings = {

  /*
   * Environment to build our application for
   *
   * If we have passed an environment via a
   * CLI option, then use that. If not attempt
   * to use the NODE_ENV. If not set, use production.
   */
  environment : (!!argv.env
                  ? argv.env
                  : process.env.NODE_ENV || 'production',


  /*
   * Where is our config folder?
   */
  configFolder : '/js/config',

  /*
   * Where is our code?
   */
  srcFolder    : '/js/src',

  /*
   * Where are we building to?
   */
  buildFolder  : '/js/build',

  /*
   * Where should the final file be?
   */
  destFolder   : '/public/js'

};

/**
 * Clean Task
 *
 * Clears the build folder from our
 * previous builds files.
 */
Gulp.task('clean', function(cb) {
  Del([
    settings.buildFolder + '/**/*'
  ], cb);
});

/**
 * Config Task
 *
 * Get the configuration file, rename it
 * and move it to be built.
 */
Gulp.task('config', function() {
  return Gulp.src(settings.configFolder + '/' + settings.environment + '.js')
             .pipe(Rename('config.js'))
             .pipe(Gulp.desk(settings.buildFolder));
});

/**
 * Src Task
 *
 * Grabs all the files from the src folder and
 * places them in our build folder.
 */
Gulp.task('src', function() {
  return Gulp.src(settings.srcFolder + '/**/*')
             .pipe(Gulp.dest(settings.buildFolder));
});

/**
 * Build Task
 *
 * Build our transpiled/compiled and config
 * files in to one awesome file.
 */
Gulp.task('build', function() {
  return Gulp.src(settings.srcFolder + '/app.js')
             .pipe(// Employ your build system)
             .pipe(settings.destFolder);
});


/**
 * Default Task
 *
 * Run the above tasks in the correct order
 */
Gulp.task('default', function(cb) {
  RunSequence([
    'clean',
    'config',
    'src',
    'build'
  ], cb);
});

/**
 * Watch Task
 *
 * Run 'gulp watch' to build when a file has been saved.
 */
Gulp.task('watch', function() {
  return Gulp.watch([
    settings.srcFolder + '/**/*',
    settings.configFolder + '/**/*'
  ], {}, function() {
    Gulp.start('default');
  });
});