Brocfile.js

const funnel = require('broccoli-funnel');
const merge = require('broccoli-merge-trees');
const compileSass = require('broccoli-sass-source-maps')(require('sass'));
const esLint = require("broccoli-lint-eslint");
const sassLint = require("broccoli-sass-lint");
const Rollup = require("broccoli-rollup");
const LiveReload = require('broccoli-livereload');
const CleanCss = require('broccoli-clean-css');
const log = require('broccoli-stew').log;
const babel = require("rollup-plugin-babel");
const nodeResolve = require('rollup-plugin-node-resolve');
const commonjs = require('rollup-plugin-commonjs');
const uglify = require('rollup-plugin-uglify').uglify;
const env = require('broccoli-env').getEnv() || 'development';
const isProduction = env === 'production';

console.log('Environmental: ' + env);

const appRoot = "app";

const html = funnel(appRoot, {
  files: ["index.html"],
  annotation: "Index file",
});

let js = esLint(appRoot, {
  persist: true
});

const rollupPlugins = [
  nodeResolve({
    jsnext: true,
    browser: true,
  }),
  commonjs({
    include: 'node_modules/**',
  }),
  babel({
    exclude: 'node_modules/**',
  }),
];

if (isProduction) {
  rollupPlugins.push(uglify());
}

js = new Rollup(js, {
  inputFiles: ['**/*.js'],
  rollup: {
    input: 'app.js',
    output: {
      file: 'assets/app.js',
      format: 'es',
      sourcemap: !isProduction,
    },
    plugins: rollupPlugins,
  }
});

let css = sassLint(appRoot + '/styles', {
  disableTestGenerator: true,
});

css = compileSass(
  [appRoot],
  'styles/main.scss',
  'assets/app.css',
  {
    sourceMap: !isProduction,
    sourceMapContents: true,
    annotation: "Sass files"
  }
);

if (isProduction) {
  css = new CleanCss(css);
}

const public = funnel('public', {
  annotation: "Public files",
});

let tree = merge([html, js, css, public], {annotation: "Final output"});

if (!isProduction) {
  tree = log(tree, {
    output: 'tree',
  });

  tree = new LiveReload(tree, {
    target: 'index.html',
  });
}

module.exports = tree;