Webpack how to build production code and how to use it

Question

I am very new to webpack, I found that in production build we can able to reduce the size of overall code. Currently webpack builds around 8MB files and main.js around 5MB. How to reduce the size of code in production build? I found a sample webpack configurtion file from internet and I configured for my application and I run npm run build and its started building and it generated some files in ./dist/ directory.

1. Still these files are heavy(same as development version)
2. How to use these files? Currently I am using webpack-dev-server to run the application.

package.json file

{   "name": "MyAPP",   "version": "0.1.0",   "description": "",   "main": "src/server/server.js",   "repository": {     "type": "git",     "url": ""   },   "keywords": [   ],   "author": "Iam",   "license": "MIT",   "homepage": "http://example.com",   "scripts": {     "test": "",     "start": "babel-node src/server/bin/server",     "build": "rimraf dist && NODE_ENV=production webpack --config ./webpack.production.config.js --progress --profile --colors"   },   "dependencies": {     "scripts" : "", ...   },   "devDependencies": {     "scripts" : "", ...   } } 

webpack.config.js

var path = require('path'); var webpack = require('webpack'); var HtmlWebpackPlugin = require('html-webpack-plugin'); var public_dir = "src/frontend"; var ModernizrWebpackPlugin = require('modernizr-webpack-plugin');  module.exports = {   devtool: 'eval-source-map',   entry: [     'webpack-hot-middleware/client?reload=true',     path.join(__dirname, public_dir , 'main.js')   ],   output: {     path: path.join(__dirname, '/dist/'),     filename: '[name].js',     publicPath: '/'   },   plugins: [     plugins   ],   module: {     loaders: [loaders]   } }; 

webpack.production.config.js

var path = require('path'); var webpack = require('webpack'); var HtmlWebpackPlugin = require('html-webpack-plugin'); var public_dir = "src/frontend"; var ModernizrWebpackPlugin = require('modernizr-webpack-plugin'); console.log(path.join(__dirname, 'src/frontend' , 'index.html'));  module.exports = {   devtool: 'eval-source-map',   entry: [     'webpack-hot-middleware/client?reload=true',     path.join(__dirname, 'src/frontend' , 'main.js')   ],   output: {     path: path.join(__dirname, '/dist/'),     filename: '[name].js',     publicPath: '/'   },   plugins: [plugins],   resolve: {     root: [path.resolve('./src/frontend/utils'), path.resolve('./src/frontend')],     extensions: ['', '.js', '.css']   },    module: {     loaders: [loaders]   } }; 

Answer 1

You can add the plugins as suggested by @Vikramaditya. Then to generate the production build. You have to run the the command

NODE_ENV=production webpack --config ./webpack.production.config.js 

If using babel, you will also need to prefix BABEL_ENV=node to the above command.

Answer 2

After observing number of viewers to this question I decided to conclude an answer from Vikramaditya and Sandeep.

To build the production code the first thing you have to create is production configuration with optimization packages like,

  new webpack.optimize.CommonsChunkPlugin('common.js'),   new webpack.optimize.DedupePlugin(),   new webpack.optimize.UglifyJsPlugin(),   new webpack.optimize.AggressiveMergingPlugin() 

Then in the package.json file you can configure the build procedure with this production configuration

"scripts": {     "build": "NODE_ENV=production webpack --config ./webpack.production.config.js" }, 

now you have to run the following command to initiate the build

npm run build 

As per my production build configuration webpack will build the source to ./dist directory.

Now your UI code will be available in ./dist/ directory. Configure your server to serve these files as static assets. Done!