rollup.es.config.js

import sourcemaps from 'rollup-plugin-sourcemaps';
import license from 'rollup-plugin-license';

const path = require('path');

export default {
  output: {
    format: 'es',
    sourcemap: true
  },
  plugins: [
    sourcemaps(),
    license({
      sourceMap: true,

      banner: {
        file: path.join(__dirname, 'license-banner.txt'),
        encoding: 'utf-8'
      }
    })
  ],
  onwarn: () => {
    return;
  }
};