webpack.config.js

const webpack = require('webpack');
const path = require('path');
const mode = require('yargs').argv.mode;
const pkg = require('./package.json');

let libraryName = pkg.name;

let outputFile;

if (mode === 'production') { outputFile = 'index.js'; }
else { outputFile = libraryName + '.js'; }

const config = {
  mode: mode,
  entry: __dirname + '/src/index.js',
  devtool: 'source-map',
  output: {
    path: __dirname + '/dist',
    filename: outputFile,
    library: libraryName,
    libraryTarget: 'umd',
    umdNamedDefine: true,
    libraryExport: 'default'
  },
  module: {
    rules: [
      {
        test: /(\.jsx|\.js)$/,
        loader: 'babel-loader',
        exclude: /(node_modules|bower_components)/
      },
      {
        test: /\.css$/,
        use: [
          'style-loader',
          'css-loader'
        ]
      }
    ]
  },
  resolve: {
    modules: [path.resolve('./node_modules'), path.resolve('./src')],
    extensions: ['.json', '.js']
  }
};

module.exports = config;