# koa-webpack-middleware

**Repository Path**: mirrors_leecade/koa-webpack-middleware

## Basic Information

- **Project Name**: koa-webpack-middleware
- **Description**: webpack dev&hot middleware for koa2
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2020-08-09
- **Last Updated**: 2026-02-14

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# koa-webpack-middleware

[![npm version](http://img.shields.io/npm/v/koa-webpack-middleware.svg?style=flat-square)](https://npmjs.org/package/koa-webpack-middleware "View this project on npm")
[![Circle CI](https://circleci.com/gh/leecade/koa-webpack-middleware.svg)](https://circleci.com/gh/leecade/koa-webpack-middleware)
[![js-standard-style](https://img.shields.io/badge/code%20style-standard-brightgreen.svg)](http://standardjs.com/)

[webpack-dev-middleware](https://github.com/webpack/webpack-dev-middleware) for [koa2](https://github.com/koajs/koa/tree/v2.x) with [HMR](http://webpack.github.io/docs/hot-module-replacement-with-webpack.html)(hot module replacement) supports.

## Install

```sh
$ npm i koa-webpack-middleware -D
```

## Depends

This middleware designd for koa2 ecosystem, make sure installed the right version:

```sh
npm i koa@next -S
```

## Usage

> See [example/](./example/) for an example of usage.

```js
import webpack from 'webpack'
import { devMiddleware, hotMiddleware } from 'koa-webpack-middleware'
import devConfig from './webpack.config.dev'
const compile = webpack(devConfig)
app.use(devMiddleware(compile, {
    // display no info to console (only warnings and errors)
    noInfo: false,

    // display nothing to the console
    quiet: false,

    // switch into lazy mode
    // that means no watching, but recompilation on every request
    lazy: true,

    // watch options (only lazy: false)
    watchOptions: {
        aggregateTimeout: 300,
        poll: true
    },

    // public path to bind the middleware to
    // use the same as in webpack
    publicPath: "/assets/",

    // custom headers
    headers: { "X-Custom-Header": "yes" },

    // options for formating the statistics
    stats: {
        colors: true
    }
}))
app.use(hotMiddleware(compile, {
  // log: console.log,
  // path: '/__webpack_hmr',
  // heartbeat: 10 * 1000
}))
```

## HMR configure

1. webpack `plugins` configure

    ```js
    plugins: [
        new webpack.optimize.OccurrenceOrderPlugin(),
        new webpack.HotModuleReplacementPlugin(),
        new webpack.NoErrorsPlugin()
    ]
    ```
2. webpack `entry` configure

    ```sh
    $ npm i eventsource-polyfill -D
    ```

    ```js
    entry: {
      'index': [
        // For old browsers
        'eventsource-polyfill',
        'webpack-hot-middleware/client?path=/__webpack_hmr&timeout=20000',
        'index.js']
    },
    ```

3. webpack `loader` configure 
    
    ```sh
    $ npm i babel-preset-es2015 babel-preset-stage-0 -D
    ```

    ```js
    {
      test: /\.js$/,
      loader: 'babel',
      query: {
        'presets': ['es2015', 'stage-0']
        }
      },
      include: './src'
    }
    ```

    > HMR for react project

    ```sh
    $ npm i babel-preset-react babel-preset-react-hmre -D
    ```

    ```js
    {
      test: /\.jsx?$/,
      loader: 'babel',
      query: {
        'presets': ['es2015', 'stage-0', 'react'],
        'env': {
          'development': {
            'presets': ['react-hmre']
          }
        }
      },
      include: './src'
    }
    ```

4. put the code in your entry file to enable HMR

    > React project do not need

    ```js
    if (module.hot) {
      module.hot.accept()
    }
    ```

That's all, you're all set!