webpack-dev-server
Advanced tools
webpack-dev-server is a development server that provides live reloading. It is intended to be used with webpack, a module bundler. It uses webpack's watch mode and, when changes are detected, it recompiles the bundle and notifies the client to reload the page.
Live Reloading
Automatically reloads the page when files are changed. The 'hot' option enables Hot Module Replacement without page refresh as fallback in case of build failures.
module.exports = {
devServer: {
contentBase: './dist',
hot: true
}
};Custom Middleware
Allows developers to add custom routes before the server starts. Useful for mocking an API or other custom server logic.
module.exports = {
devServer: {
before: function(app, server) {
app.get('/some/path', function(req, res) {
res.json({ custom: 'response' });
});
}
}
};Proxying API Requests
Redirects API calls to another server. This is useful when you have a separate API backend development server and you want to send API requests on the same domain.
module.exports = {
devServer: {
proxy: {
'/api': 'http://localhost:3000'
}
}
};HTTPS Support
Allows serving the webpack application over HTTPS. This is useful for testing applications that require secure connections.
module.exports = {
devServer: {
https: true
}
};BrowserSync is an automation tool that makes web development faster. It synchronizes file changes and interactions across multiple devices. It's similar to webpack-dev-server but works across multiple browsers and devices.
Lite-server is a lightweight development server that serves a web app, opens it in the browser, and refreshes the browser on file changes. It is built on top of BrowserSync and provides fewer configuration options compared to webpack-dev-server.
Serve is a static server that lets you serve static files quickly. It is simpler than webpack-dev-server and does not have built-in support for live reloading or module bundling.
http-server is a simple, zero-configuration command-line HTTP server. It is powerful and has the ability to serve static files, but lacks the advanced features of webpack-dev-server like live reloading and module hot replacement.
Use webpack with a development server that provides live reloading. This should be used for development only.
It uses webpack-dev-middleware under the hood, which provides fast in-memory access to the webpack assets.
First things first, install the module:
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.
There are two main, recommended methods of using the module:
The easiest way to use it is with the webpack CLI. In the directory where your
webpack.config.js is, run:
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.
-d, --devtool <value> Determine source maps to use.
--no-devtool Do not generate source maps.
--entry <value...> The entry point(s) of your application e.g. ./src/main.js.
--mode <value> Defines the mode to pass to webpack.
--name <value> Name of the configuration. Used when loading multiple configurations.
-o, --output-path <value> Output location of the file generated by webpack e.g. ./dist/.
--stats [value] It instructs webpack on how to treat the stats e.g. verbose.
--no-stats Disable stats output.
-t, --target <value...> Sets the build target e.g. node.
--no-target Negative 'target' option.
--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 Negative 'bonjour' option.
--no-client Negative 'client' option.
--client-logging <value> Allows to specify options for client script in the browser or disable client script.
--client-overlay Enables a full-screen overlay in the browser when there are compiler errors or warnings.
--no-client-overlay Negative 'client-overlay' option.
--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-progress Prints compilation progress in percentage in the browser.
--no-client-progress Negative 'client-progress' option.
--client-web-socket-transport <value> Allows to set custom web socket transport to communicate with dev server.
--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-pathname <value> Tells clients connected to devServer to use the provided path to connect.
--client-web-socket-url-password <value> Tells clients connected to devServer to use the provided password to authenticate.
--client-web-socket-url-port <value> Tells clients connected to devServer to use the provided port.
--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.
--compress Enables gzip compression for everything served.
--no-compress Negative 'compress' option.
--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 Negative 'hot' option.
--http2 Allows to serve over HTTP/2 using SPDY.
--no-http2 Negative 'http2' option.
--https Allows to configure the server's listening socket for TLS (by default, dev server will be served over HTTP).
--no-https Negative 'https' option.
--https-passphrase <value> Passphrase for a pfx file.
--https-request-cert Request for an SSL certificate.
--no-https-request-cert Negative 'https-request-cert' option.
--https-cacert <value> Path to an SSL CA certificate.
--https-key <value> Path to an SSL key.
--https-pfx <value> Path to an SSL pfx file.
--https-cert <value> Path to an SSL certificate.
--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 Negative 'live-reload' option.
--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 Negative 'open' option.
--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.
--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 Negative 'static-serve-index' option.
--static-watch Watches for files in static content directory.
--no-static-watch Negative 'static-watch' option.
--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.
--web-socket-server <value> Allows to set web socket server and options (by default 'ws').
--no-web-socket-server Negative 'web-socket-server' option.
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.
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:
{
"scripts": {
"serve": "webpack serve"
}
}
And run the following in your terminal/console:
npm run serve
NPM will automagically reference the binary in node_modules for you, and
execute the file or command.
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 for more use cases and options.
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.
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 for the module. If you see an opportunity for improvement of those docs, please head over to the webpack.js.org repo and open a pull request.
From there, we encourage users to visit the webpack Gitter chat and
talk to the fine folks there. If your quest for answers comes up dry in chat,
head over to StackOverflow 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 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.
We welcome your contributions! Please have a read of CONTRIBUTING.md for more information on how to get involved.
This project is heavily inspired by peerigon/nof5.
FAQs
Serves a webpack app. Updates the browser on changes.
The npm package webpack-dev-server receives a total of 14,928,627 weekly downloads. As such, webpack-dev-server popularity was classified as popular.
We found that webpack-dev-server demonstrated a healthy version release cadence and project activity because the last version was released less than a year ago. It has 4 open source maintainers collaborating on the project.
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