webpack.config.js

const OptimizeCssAssetsPlugin = require('optimize-css-assets-webpack-plugin');
const ExtractTextPlugin = require('extract-text-webpack-plugin');
const CleanWebpackPlugin = require('clean-webpack-plugin');
const CopyWebpackPlugin = require('copy-webpack-plugin');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const merge = require('webpack-merge');
const webpack = require('webpack');
const path = require('path');

const paths = {
    src: path.resolve(__dirname, 'src'),
    build: path.resolve(__dirname, 'build')
};

const uglifyConfig = {
    sourceMap: false,
    warnings: false,
    mangle: true,
    minimize: true
};

const htmlConfig = {
    template: path.join(paths.src, 'index.html'),
    minify : {
        collapseWhitespace: true
    }
};

const common = {
    devServer: {
        contentBase: path.join(__dirname, 'build'),
    },
    entry: path.join(paths.src, 'index.js'),
    resolve: {
        extensions: ['.js', '.jsx', '.ts', '.tsx']
    },
    module: {
        rules: [
            {
                test: /\.(js|jsx)$/,
                exclude: /(node_modules)/,
                use: {
                    loader: 'babel-loader',
                    options: {
                        presets: ['env']
                    }
                }
            },
            {
                test: /\.(ts)$/,
                exclude: /(node_modules)/,
                use: {
                    loader: 'awesome-typescript-loader',
                    options: {
                        useCache: false,
                    }
                }
            },
            {
                test: /\.(css)$/,
                use: ExtractTextPlugin.extract({
                    fallback: 'style-loader',
                    use: 'css-loader'
                })
            },
            {
                test: /\.(png|jpg|gif)$/,
                exclude: /(node_modules)/,
                use: [
                    {
                        loader: 'file-loader',
                        options: {}
                    }
                ]
            }
        ]
    },
    plugins: [
        new CleanWebpackPlugin([paths.build]),
        new HtmlWebpackPlugin(htmlConfig),
        new ExtractTextPlugin('styles.[contenthash].css'),
    ]
};

const devSettings = {
    devtool: 'eval-source-map',
    devServer: {
        historyApiFallback: true,
    },
    output: {
        path: paths.build,
        filename: 'bundle.[hash].js',
        publicPath: '/'
    },
    plugins: [
        new webpack.HotModuleReplacementPlugin(),
        new CleanWebpackPlugin([paths.build]),
    ]
};

const prodSettings = {
    devtool: 'source-map',
    output: {
        path: paths.build,
        filename: 'bundle.[hash].js',
        publicPath: '/build/'
    },
    plugins: [
        new webpack.DefinePlugin({ 'process.env': {
                NODE_ENV: JSON.stringify('production')
            }}),
        new webpack.optimize.UglifyJsPlugin(uglifyConfig),
        new OptimizeCssAssetsPlugin(),
        new webpack.optimize.OccurrenceOrderPlugin(),
    ]
};

/**
 * Exports
 **/

const TARGET = process.env.npm_lifecycle_event;
process.env.BABEL_ENV = TARGET;

if (TARGET === 'start') {
    module.exports = merge(common, devSettings)
}

if (TARGET === 'build' || !TARGET) {
    module.exports = merge(common, prodSettings)
}