webpack.config.js

const path = require('path')
const webpack = require('webpack')
const fs = require('fs')
const CopyPlugin = require('copy-webpack-plugin')

module.exports = {
  entry: './src/index.js',
  output: {
    libraryTarget: 'commonjs',
    filename: 'index.js',
    path: path.resolve(__dirname, 'miniprogram_dist'),
  },
  devtool: '',
  module: {
    rules: [{
      test: /\.js$/i,
      use: [{
        loader: 'eslint-loader',
      }, {
        loader: 'babel-loader',
        options: {
          presets: ['@babel/preset-env'],
          plugins: ['@babel/plugin-proposal-class-properties'],
        },
      }, {
        loader: 'string-replace-loader',
        options: {
          multiple: [{
            search: `'__LOTTIE_CANVAS__'`,
            replace: fs.readFileSync('./node_modules/lottie-web/build/player/lottie_canvas.js', {encoding: 'utf8'}),
          }, {
            search: '__[STANDALONE]__',
            replace: '',
          }]
        }
      }],
      exclude: /node_modules/
    }]
  },
  amd: false,
  plugins: [
    new webpack.DefinePlugin({
      'define': {}
    }),
    new webpack.optimize.ModuleConcatenationPlugin(),
    new CopyPlugin({
      patterns: [
        { 
          from: path.resolve(__dirname, 'src', 'index.d.ts'), 
          to: path.resolve(__dirname, 'miniprogram_dist', 'index.d.ts')
        },
      ],
    }),
  ],
}