frontend/gulp/tasks/hassio-panel.js

var gulp = require('gulp');
const rename = require('gulp-rename');

const {
  stripImportsStrategy,
} = require('../common/strategy');
const minifyStream = require('../common/transform').minifyStream;
const {
  bundledStreamFromHTML,
  findDependencies
} = require('../common/html');

const { polymer_dir } = require('../config');

const DEPS_TO_STRIP = [
  'bower_components/font-roboto/roboto.html',
  'bower_components/paper-styles/color.html',
  'bower_components/iron-meta/iron-meta.html',
];
const DEPS_TO_STRIP_RECURSIVELY = [
  'bower_components/polymer/polymer.html',
];

gulp.task(
  'hassio-panel',
  async () => {
    const toStrip = [...DEPS_TO_STRIP];

    for (let dep of DEPS_TO_STRIP_RECURSIVELY) {
      toStrip.push(dep);
      const deps = await findDependencies(polymer_dir, dep);
      for (const importUrl of deps) {
        toStrip.push(importUrl);
      }
    }

    const stream = await bundledStreamFromHTML(
      'panels/hassio/hassio-main.html', {
        strategy: stripImportsStrategy(toStrip)
      }
    );

    return minifyStream(stream)
        .pipe(rename('hassio-main.html'))
        .pipe(gulp.dest('build-temp/'));
  }
);