webpack-dev-server/README.md

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# webpack-dev-server

Use [webpack](https://webpack.js.org) with a development server that provides
live reloading. This should be used for **development only**.

It uses [webpack-dev-middleware][middleware-url] under the hood, which provides
fast in-memory access to the webpack assets.

## Table of Contents

- [Getting Started](#getting-started)
- [Usage](#usage)
  - [With the CLI](#with-the-cli)
  - [With NPM Scripts](#with-npm-scripts)
  - [With the API](#with-the-api)
  - [The Result](#the-result)
- [Browser Support](#browser-support)
- [Support](#support)
- [Contributing](#contributing)
- [Attribution](#attribution)
- [License](#license)

## Getting Started

First things first, install the module:

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

_Note: While you can install and run webpack-dev-server globally, we recommend
installing it locally. webpack-dev-server will always use a local installation
over a global one._

## Usage

There are two main, recommended methods of using the module:

### With the CLI

The easiest way to use it is with the [webpack CLI](https://webpack.js.org/api/cli/). In the directory where your
`webpack.config.js` is, run:

```console
npx webpack serve
```

Following options are available with `webpack serve`:

```
Usage: webpack serve|server|s [entries...] [options]

Run the webpack dev server.

Options:
  -c, --config <value...>                   Provide path to a webpack configuration file e.g. ./webpack.config.js.
  --config-name <value...>                  Name of the configuration to use.
  -m, --merge                               Merge two or more configurations using 'webpack-merge'.
  --env <value...>                          Environment passed to the configuration when it is a function.
  --node-env <value>                        Sets process.env.NODE_ENV to the specified value.
  --progress [value]                        Print compilation progress during build.
  -j, --json [value]                        Prints result as JSON or store it in a file.
  --entry <value...>                        The entry point(s) of your application e.g. ./src/main.js.
  -o, --output-path <value>                 Output location of the file generated by webpack e.g. ./dist/.
  -t, --target <value>                      Sets the build target e.g. node.
  -d, --devtool <value>                     Determine source maps to use.
  --no-devtool                              Do not generate source maps.
  --mode <value>                            Defines the mode to pass to webpack.
  --name <value>                            Name of the configuration. Used when loading multiple configurations.
  --stats [value]                           It instructs webpack on how to treat the stats e.g. verbose.
  --no-stats                                Disable stats output.
  --watch-options-stdin                     Stop watching when stdin stream has ended.
  --no-watch-options-stdin                  Do not stop watching when stdin stream has ended.
  --allowed-hosts <value...>                Allows to enumerate the hosts from which access to the dev server are allowed (useful when you are proxying dev server, by default is 'auto').
  --allowed-hosts-reset                     Clear all items provided in 'allowedHosts' configuration. Allows to enumerate the hosts from which access to the dev server are allowed (useful when you are proxying dev server, by default is 'auto').
  --bonjour                                 Allows to broadcasts dev server via ZeroConf networking on start.
  --no-bonjour                              Disallows to broadcasts dev server via ZeroConf networking on start.
  --client-web-socket-transport <value>     Allows to set custom web socket transport to communicate with dev server.
  --no-client                               Negative 'client' option.
  --client-logging <value>                  Allows to specify options for client script in the browser or disable client script.
  --client-progress                         Prints compilation progress in percentage in the browser.
  --no-client-progress                      Does not print compilation progress in percentage in the browser.
  --client-reconnect [value]                Tells dev-server the number of times it should try to reconnect the client.
  --no-client-reconnect                     Tells dev-server to not to try to connect the client.
  --client-overlay                          Enables a full-screen overlay in the browser when there are compiler errors or warnings.
  --no-client-overlay                       Disables a full-screen overlay in the browser when there are compiler errors or warnings.
  --client-overlay-errors                   Enables a full-screen overlay in the browser when there are compiler errors.
  --no-client-overlay-errors                Negative 'client-overlay-errors' option.
  --client-overlay-warnings                 Enables a full-screen overlay in the browser when there are compiler warnings.
  --no-client-overlay-warnings              Negative 'client-overlay-warnings' option.
  --client-web-socket-url <value>           Allows to specify URL to web socket server (useful when you're proxying dev server and client script does not always know where to connect to).
  --client-web-socket-url-hostname <value>  Tells clients connected to devServer to use the provided hostname.
  --client-web-socket-url-port <value>      Tells clients connected to devServer to use the provided port.
  --client-web-socket-url-pathname <value>  Tells clients connected to devServer to use the provided path to connect.
  --client-web-socket-url-protocol <value>  Tells clients connected to devServer to use the provided protocol.
  --client-web-socket-url-username <value>  Tells clients connected to devServer to use the provided username to authenticate.
  --client-web-socket-url-password <value>  Tells clients connected to devServer to use the provided password to authenticate.
  --web-socket-server <value>               Deprecated: please use 'webSocketServer.type'/'--web-socket-server-type' option. Allows to set web socket server and options (by default 'ws').
  --no-web-socket-server                    Negative 'web-socket-server' option.
  --web-socket-server-type <value>          Allows to set web socket server and options (by default 'ws').
  --compress                                Enables gzip compression for everything served.
  --no-compress                             Disables gzip compression for everything served.
  --history-api-fallback                    Allows to proxy requests through a specified index page (by default 'index.html'), useful for Single Page Applications that utilise the HTML5 History API.
  --no-history-api-fallback                 Negative 'history-api-fallback' option.
  --host <value>                            Allows to specify a hostname to use.
  --hot [value]                             Enables Hot Module Replacement.
  --no-hot                                  Disables Hot Module Replacement.
  --http2                                   Allows to serve over HTTP/2 using SPDY. Deprecated, it will be removed in favor of the `server` option.
  --no-http2                                Does not serve over HTTP/2 using SPDY.
--https                                   Allows to configure the server's listening socket for TLS (by default, dev server will be served over HTTP). Deprecated, it will be removed in favor
                                            of the `server` option.
  --no-https                                Disallows to configure the server's listening socket for TLS (by default, dev server will be served over HTTP).
  --https-passphrase <value>                Passphrase for a pfx file. Deprecated, it will be removed in favor of the `server.options.passphrase` option.
  --https-request-cert                      Request for an SSL certificate. Deprecated, it will be removed in favor of the `server.options.requestCert`
                                            option.
  --no-https-request-cert                   Negative 'https-request-cert' option.
  --https-ca <value...>                     Path to an SSL CA certificate or content of an SSL CA certificate. Deprecated, it will be removed in favor of the
                                            `server.options.ca` option.
  --https-ca-reset                          Clear all items provided in 'https.ca' configuration. Path to an SSL CA certificate or content of an SSL CA
                                            certificate. Deprecated, it will be removed in favor of the `server.options.ca` option.
  --https-cacert <value...>                 Path to an SSL CA certificate or content of an SSL CA certificate. Deprecated, it will be removed in favor of the
                                            `server.options.cacert` option.
  --https-cacert-reset                      Clear all items provided in 'https.cacert' configuration. Path to an SSL CA certificate or content of an SSL CA
                                            certificate. Deprecated, it will be removed in favor of the `server.options.cacert` option.
  --https-cert <value...>                   Path to an SSL certificate or content of an SSL certificate. Deprecated, it will be removed in favor of the
                                            `server.options.cert` option.
  --https-cert-reset                        Clear all items provided in 'https.cert' configuration. Path to an SSL certificate or content of an SSL
                                            certificate. Deprecated, it will be removed in favor of the `server.options.cert` option.
  --https-crl <value...>                    Path to PEM formatted CRLs (Certificate Revocation Lists) or content of PEM formatted CRLs (Certificate
                                            Revocation Lists). Deprecated, it will be removed in favor of the `server.options.crl` option.
  --https-crl-reset                         Clear all items provided in 'https.crl' configuration. Path to PEM formatted CRLs (Certificate Revocation Lists)
                                            or content of PEM formatted CRLs (Certificate Revocation Lists). Deprecated, it will be removed in favor of the
                                            `server.options.crl` option.
  --https-key <value...>                    Path to an SSL key or content of an SSL key. Deprecated, it will be removed in favor of the `server.options.key`
                                            option.
  --https-key-reset                         Clear all items provided in 'https.key' configuration. Path to an SSL key or content of an SSL key. Deprecated,
                                            it will be removed in favor of the `server.options.key` option.
  --https-pfx <value...>                    Path to an SSL pfx file or content of an SSL pfx file. Deprecated, it will be removed in favor of the
                                            `server.options.pfx` option.
  --https-pfx-reset                         Clear all items provided in 'https.pfx' configuration. Path to an SSL pfx file or content of an SSL pfx file.
                                            Deprecated, it will be removed in favor of the `server.options.pfx` option.
  --ipc [value]                             Listen to a unix socket.
  --live-reload                             Enables reload/refresh the page(s) when file changes are detected (enabled by default).
  --no-live-reload                          Disables reload/refresh the page(s) when file changes are detected (enabled by default)
  --magic-html                              Tells dev-server whether to enable magic HTML routes (routes corresponding to your webpack output, for example '/main' for 'main.js').
  --no-magic-html                           Disables magic HTML routes (routes corresponding to your webpack output, for example '/main' for 'main.js').
  --open [value...]                         Allows to configure dev server to open the browser(s) and page(s) after server had been started (set it to true to open your default browser).
  --no-open                                 Does not open the default browser.
  --open-target <value...>                  Opens specified page in browser.
  --open-app-name <value...>                Open specified browser.
  --open-app <value...>                     Open specified browser.
  --open-reset                              Clear all items provided in 'open' configuration. Allows to configure dev server to open the browser(s) and page(s) after server had been started (set it to true to open your default browser).
  --open-target-reset                       Clear all items provided in 'open.target' configuration. Opens specified page in browser.
  --open-app-name-reset                     Clear all items provided in 'open.app.name' configuration. Open specified browser.
  --port <value>                            Allows to specify a port to use.
  --server-type <value>                     Allows to set server and options (by default 'http').
  --server-options-passphrase <value>       Passphrase for a pfx file.
  --server-options-request-cert             Request for an SSL certificate.
  --no-server-options-request-cert          Negative 'server-options-request-cert' option.
  --server-options-ca <value...>            Path to an SSL CA certificate or content of an SSL CA certificate.
  --server-options-ca-reset                 Clear all items provided in 'server.options.ca' configuration. Path to an SSL CA certificate or content
                                            of an SSL CA certificate.
  --server-options-cacert <value...>        Path to an SSL CA certificate or content of an SSL CA certificate.
  --server-options-cacert-reset             Clear all items provided in 'server.options.cacert' configuration. Path to an SSL CA certificate or
                                            content of an SSL CA certificate.
  --server-options-cert <value...>          Path to an SSL certificate or content of an SSL certificate.
  --server-options-cert-reset               Clear all items provided in 'server.options.cert' configuration. Path to an SSL certificate or content
                                            of an SSL certificate.
  --server-options-crl <value...>           Path to PEM formatted CRLs (Certificate Revocation Lists) or content of PEM formatted CRLs (Certificate
                                            Revocation Lists).
  --server-options-crl-reset                Clear all items provided in 'server.options.crl' configuration. Path to PEM formatted CRLs (Certificate
                                            Revocation Lists) or content of PEM formatted CRLs (Certificate Revocation Lists).
  --server-options-key <value...>           Path to an SSL key or content of an SSL key.
  --server-options-key-reset                Clear all items provided in 'server.options.key' configuration. Path to an SSL key or content of an SSL
                                            key.
  --server-options-pfx <value...>           Path to an SSL pfx file or content of an SSL pfx file.
  --server-options-pfx-reset                Clear all items provided in 'server.options.pfx' configuration. Path to an SSL pfx file or content of
                                            an SSL pfx file.
  --static [value...]                       Allows to configure options for serving static files from directory (by default 'public' directory).
  --no-static                               Negative 'static' option.
  --static-directory <value...>             Directory for static contents.
  --static-public-path <value...>           The static files will be available in the browser under this public path.
  --static-serve-index                      Tells dev server to use serveIndex middleware when enabled.
  --no-static-serve-index                   Does not tell dev server to use serveIndex middleware.
  --static-watch                            Watches for files in static content directory.
  --no-static-watch                         Does not watch for files in static content directory.
  --static-reset                            Clear all items provided in 'static' configuration. Allows to configure options for serving static files from directory (by default 'public' directory).
  --static-public-path-reset                Clear all items provided in 'static.publicPath' configuration. The static files will be available in the browser under this public path.
  --watch-files <value...>                  Allows to configure list of globs/directories/files to watch for file changes.
  --watch-files-reset                       Clear all items provided in 'watchFiles' configuration. Allows to configure list of globs/directories/files to watch for file changes.

Global options:
  --color                                   Enable colors on console.
  --no-color                                Disable colors on console.
  -v, --version                             Output the version number of 'webpack', 'webpack-cli' and 'webpack-dev-server' and commands.
  -h, --help [verbose]                      Display help for commands and options.

To see list of all supported commands and options run 'webpack --help=verbose'.

Webpack documentation: https://webpack.js.org/.
CLI documentation: https://webpack.js.org/api/cli/.
Made with ♥ by the webpack team.
```

_**Note**: For more information on above options explore this [link](https://webpack.js.org/configuration/dev-server/)._

### With NPM Scripts

NPM package.json scripts are a convenient and useful means to run locally installed
binaries without having to be concerned about their full paths. Simply define a
script as such:

```json
{
  "scripts": {
    "serve": "webpack serve"
  }
}
```

And run the following in your terminal/console:

```console
npm run serve
```

NPM will automagically reference the binary in `node_modules` for you, and
execute the file or command.

### With the API

While it's recommended to run webpack-dev-server via the CLI, you may also choose to start a server via the API.

See the related [API documentation for `webpack-dev-server`](https://webpack.js.org/api/webpack-dev-server/).

### The Result

Either method will start a server instance and begin listening for connections
from `localhost` on port `8080`.

webpack-dev-server is configured by default to support live-reload of files as
you edit your assets while the server is running.

See [**the documentation**][docs-url] for more use cases and options.

## Browser Support

While `webpack-dev-server` transpiles the client (browser) scripts to an ES5
state, the project only officially supports the _last two versions of major
browsers_. We simply don't have the resources to support every whacky
browser out there.

If you find a bug with an obscure / old browser, we would actively welcome a
Pull Request to resolve the bug.

## Support

We do our best to keep Issues in the repository focused on bugs, features, and
needed modifications to the code for the module. Because of that, we ask users
with general support, "how-to", or "why isn't this working" questions to try one
of the other support channels that are available.

Your first-stop-shop for support for webpack-dev-server should be the excellent
[documentation][docs-url] for the module. If you see an opportunity for improvement
of those docs, please head over to the [webpack.js.org repo][wjo-url] and open a
pull request.

From there, we encourage users to visit the [webpack Gitter chat][chat-url] and
talk to the fine folks there. If your quest for answers comes up dry in chat,
head over to [StackOverflow][stack-url] and do a quick search or open a new
question. Remember; It's always much easier to answer questions that include your
`webpack.config.js` and relevant files!

If you're twitter-savvy you can tweet [#webpack][hash-url] with your question
and someone should be able to reach out and lend a hand.

If you have discovered a :bug:, have a feature suggestion, or would like to see
a modification, please feel free to create an issue on Github. _Note: The issue
template isn't optional, so please be sure not to remove it, and please fill it
out completely._

## Contributing

We welcome your contributions! Please have a read of [CONTRIBUTING.md](CONTRIBUTING.md) for more information on how to get involved.

## Attribution

This project is heavily inspired by [peerigon/nof5](https://github.com/peerigon/nof5).

## License

#### [MIT](./LICENSE)

[npm]: https://img.shields.io/npm/v/webpack-dev-server.svg
[npm-url]: https://npmjs.com/package/webpack-dev-server
[node]: https://img.shields.io/node/v/webpack-dev-server.svg
[node-url]: https://nodejs.org
[tests]: https://github.com/webpack/webpack-dev-server/workflows/webpack-dev-server/badge.svg
[tests-url]: https://github.com/webpack/webpack-dev-server/actions?query=workflow%3Awebpack-dev-server
[cover]: https://codecov.io/gh/webpack/webpack-dev-server/branch/master/graph/badge.svg
[cover-url]: https://codecov.io/gh/webpack/webpack-dev-server
[chat]: https://badges.gitter.im/webpack/webpack.svg
[chat-url]: https://gitter.im/webpack/webpack
[docs-url]: https://webpack.js.org/configuration/dev-server/#devserver
[hash-url]: https://twitter.com/search?q=webpack
[middleware-url]: https://github.com/webpack/webpack-dev-middleware
[stack-url]: https://stackoverflow.com/questions/tagged/webpack-dev-server
[uglify-url]: https://github.com/webpack-contrib/uglifyjs-webpack-plugin
[wjo-url]: https://github.com/webpack/webpack.js.org
[downloads]: https://img.shields.io/npm/dm/webpack-dev-server.svg
[contributors-url]: https://github.com/webpack/webpack-dev-server/graphs/contributors
[contributors]: https://img.shields.io/github/contributors/webpack/webpack-dev-server.svg