webpack.config.js

const path = require('path')
const webpack = require('webpack')

module.exports = {
    devtool: 'cheap-eval-source-map',
    entry: './src/index.js',
    output: {
        path: path.join(__dirname, 'public'),
        filename: 'bundle.js'
    },
    module: {
        rules: [
            {
                test: /\.js$/,
                exclude: /node_modules/,
                loader: 'babel-loader'
            },
            {
                test: /\.js$/,
                exclude: /node_modules/,
                use: ['babel-loader', 'eslint-loader']
            }
        ]
    },
    plugins: [
        new webpack.DefinePlugin({
            'process.env.NODE_ENV': JSON.stringify(process.env.NODE_ENV)
        })
    ],
    devServer: {
        contentBase: 'public/'
    }
}