config.js

const app_root = 'src'; // the app root folder: src, src_users, etc
const path = require('path');
const CleanWebpackPlugin = require('clean-webpack-plugin');
const autoprefixer = require('autoprefixer');
const ExtractTextPlugin = require("extract-text-webpack-plugin");

module.exports = {
    app_root: app_root,
    entry: [
        'webpack-dev-server/client?http://localhost:3005',
        'webpack/hot/only-dev-server',
        __dirname + '/' + app_root + '/index.js',
    ],
    output: {
        path: __dirname + '/public/js',
        publicPath: 'js/',
        filename: 'bundle.js',
    },
    module: {
        loaders: [
            {
                test: /\.js$/,
                loader: 'babel',
                exclude: /node_modules/,
            },
            {
                // https://github.com/jtangelder/sass-loader
                test: /\.scss$/,
                loaders: ['style', 'css', 'sass'],
            },
            {
              test: /\.css$/, loader: ExtractTextPlugin.extract({
                fallbackLoader: "style-loader",
                loaders: [
                  'style-loader',
                  'css-loader?importLoaders=1',
                  'postcss-loader' ]
              })
            },
            {
              test: /\.js$/,
              loaders: [ "babel-loader", "eslint-loader" ],
              exclude: /node_modules/,
            },
            {
              test: /\.(png|jpg|jpeg|gif|svg|woff|woff2)$/,
              loader: 'url-loader?limit=8192'
            }
        ],
    },
    devServer: {
        contentBase: __dirname + '/public',
                port: 3005,
                historyApiFallback: true,
                devtool: 'source-map',
//---------------- here we can declare proxy from backend -----------------
         proxy: {
            // '/': 'http://localhost:8080',
          }
     },
    plugins: [
        new ExtractTextPlugin(__dirname + '/public/css/main.css'),
        new CleanWebpackPlugin(['css', 'js'], {
          root: __dirname + '/public',
          verbose: true,
          dry: false,
        })
    ],
    postcss: function () {
      return [autoprefixer({
    browsers: ['last 2 versions']
    })];
}
};