[tests]: https://img.shields.io/circleci/project/github/shellscape/koa-webpack.svg
[tests-url]: https://circleci.com/gh/shellscape/koa-webpack

[cover]: https://codecov.io/gh/shellscape/koa-webpack/branch/master/graph/badge.svg
[cover-url]: https://codecov.io/gh/shellscape/koa-webpack

[size]: https://packagephobia.now.sh/badge?p=koa-webpack
[size-url]: https://packagephobia.now.sh/result?p=koa-webpack

koa-webpack

[![tests][tests]][tests-url]
[![cover][cover]][cover-url]
[![size][size]][size-url]

Development and Hot Module Reload Middleware for Koa2, in a single
middleware module.

This module wraps and composes
webpack-dev-middleware and
webpack-hot-client
into a single middleware module, allowing for quick and concise implementation.

As an added bonus, it'll also use the installed webpack module from your project,
and the webpack.config.js file in the root of your project, automagically, should
you choose to let it. This negates the need for all of the repetitive setup and
config that you get with koa-webpack-middleware.

Install

Using npm:

``console
npm install koa-webpack --save-dev
`

Requirements

koa-webpack is an evergreen module. 🌲 This module requires an Active LTS Node version (v8.0.0+ or v10.0.0+), and Webpack v4.0.0+.

Usage

`js
const Koa = require('koa');
const koaWebpack = require('koa-webpack');

const app = new Koa();
const options = { .. };
const middleware = await koaWebpack(options);

app.use(middleware);
`

API

$3

Returns a Promise which resolves the server middleware containing the
following additional properties:

- close(callback) (Function) - Closes both the instance of webpack-dev-middleware
and webpack-hot-client. Accepts a single Function callback parameter that is
executed when complete.
- hotClient (Object) - An instance of webpack-hot-client.
- devMiddleware (Object) - An instance of webpack-dev-middleware

Options

The middleware accepts an options Object, which can contain options for the
webpack-dev-middleware and webpack-hot-client bundled with this module.
The following is a property reference for the Object:

$3

Type: Object
optional

Should you rather that the middleware use an instance of webpack that you've
already init'd [with webpack config], you can pass it to the middleware using
this option.

Example:

`js
const webpack = require('webpack');
const config = require('./webpack.config.js');
const koaWebpack = require('koa-webpack');

const compiler = webpack(config);
const middleware = await koaWebpack({ compiler });

app.use(middleware);
`

$3

Type: Object

Should you rather that the middleware use an instance of webpack configuration
that you've already required/imported, you can pass it to the middleware using
this option.

Example:

`js
const koaWebpack = require('koa-webpack');
const config = require('./webpack.config.js');

const middleware = await koaWebpack({ config });

app.use(middleware);
`

$3

Type: String

Allows you to specify the absolute path to the Webpack config file to be used.

Example:

`js
const path = require('path');
const koaWebpack = require('koa-webpack');

// The Webpack config file would be at "./client/webpack.config.js".
const middleware = await koaWebpack({
configPath: path.join(__dirname, 'client', 'webpack.config.js')
});

app.use(middleware);
`

$3

Type: Object

The devMiddleware property should contain options for webpack-dev-middleware, a list of
which is available at webpack-dev-middleware.
Omitting this property will result in webpack-dev-middleware using its default
options.

$3

Type: Object|Boolean

The hotClient property should contain options for webpack-hot-client, a list of
which is available at webpack-hot-client.
Omitting this property will result in webpack-hot-client using its default
options.

As of v3.0.1 setting this to false will completely disable webpack-hot-client
and all automatic Hot Module Replacement functionality.

Using with koa-compress

When using koa-webpack with koa-compress,
you may experience issues with saving files and hot module reload. Please review
this issue
for more information and a workaround.

Server-Side-Rendering

When serverSideRender is set to true in config.devMiddleware, webpackStats is
accessible from ctx.state.webpackStats.

`js
app.use(async (ctx, next) => {
const assetsByChunkName = ctx.state.webpackStats.toJson().assetsByChunkName;
// do something with assetsByChunkName
})
`

For more details please refer to:
webpack-dev-middleware

Using with html-webpack-plugin

When using with html-webpack-plugin, you can access dev-middleware in-memory filesystem to serve index.html file:

`js
const middleware = await koaWebpack({ config });

app.use(middleware);

app.use(async (ctx) => {
const filename = path.resolve(webpackConfig.output.path, 'index.html')
ctx.response.type = 'html'
ctx.response.body = middleware.devMiddleware.fileSystem.createReadStream(filename)
});
`

Contributing

Please take a moment to read our contributing guidelines if you haven't yet done so.

#### CONTRIBUTING

Attribution

This module started as a fork of
koa-webpack-middleware`

License

#### MPL