webpack.config.js

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const webpack = require('webpack');

const config = {
    entry: './app/index.js',
    output: {
        path: path.resolve(__dirname, 'dist'),
        filename: 'index.bundle.js',
        publicPath: '/'
    },
    module: {
        rules: [
            {
                test: /\.(js)$/,
                use: 'babel-loader'
            },
            {
                test: /\.(css)/,
                use: ['style-loader', 'css-loader']
            },
            {
                test: /\.(sass|scss)$/,
                use: [
                    "style-loader",
                    "css-loader",
                    "sass-loader",
                ]
            }
        ]
    },
    devServer: {
        historyApiFallback: true
    },
    plugins: [
        new HtmlWebpackPlugin({
            template: 'app/index.html'
        })
    ]
};


if (process.env.NODE_ENV === 'production') {
    config.plugins.push(
        new webpack.DefinePlugin({
            'process.env': {
                'NODE_ENV': JSON.stringify(process.env.NODE_ENV)
            }
        }),
        new webpack.optimize.UglifyJsPlugin()
    );
}

module.exports = config;