Lite-server NPM

lite-server

Lightweight development only node server that serves a web app, opens it in the browser, refreshes when html or javascript change, injects CSS changes using sockets, and has a fallback page when a route is not found.

Why

BrowserSync does most of what we want in a super fast lightweight development server. It serves the static content, detects changes, refreshes the browser, and offers many customizations.

When creating a SPA there are routes that are only known to the browser. For example, /customer/21 may be a client side route for an Angular app. If this route is entered manually or linked to directly as the entry point of the Angular app (aka a deep link) the static server will receive the request, because Angular is not loaded yet. The server will not find a match for the route and thus return a 404. The desired behavior in this case is to return the index.html (or whatever starting page of the app we have defined). BrowserSync does not automatically allow for a fallback page. But it does allow for custom middleware. This is where lite-server steps in.

lite-server is a simple customized wrapper around BrowserSync to make it easy to serve SPAs.

Installation and Usage

The recommended installation method is a local NPM install for your project:

npm install lite-server --save-dev
yarn add lite-server --dev # or yarn

...and add a "script" entry within your project's package.json file:

# Inside package.json...
  "scripts": {
    "dev": "lite-server"
  },

With the above script entry, you can then start lite-server via:

npm run dev

Other options for running locally installed NPM binaries is discussed in this Stack Overflow question: How to use package installed locally in node_modules

Using on the fly

lite-server can be used with npx

npx lite-server

Global Installation

lite-server can be also installed globally, if preferred:

npm install --global lite-server

# To run:
lite-server

Custom Configuration

The default behavior serves from the current folder, opens a browser, and applies a HTML5 route fallback to ./index.html.

lite-server uses BrowserSync, and allows for configuration overrides via a local bs-config.json or bs-config.js file in your project.

You can provide custom path to your config file via -c or --config= run time options:

lite-server -c configs/my-bs-config.js

For example, to change the server port, watched file paths, and base directory for your project, create a bs-config.json in your project's folder:

{
  "port": 8000,
  "files": ["./src/**/*.{html,htm,css,js}"],
  "server": { "baseDir": "./src" }
}

You can also provide custom path to your base directory --baseDir= run time options:

lite-server --baseDir="dist"

A more complicated example with modifications to the server middleware can be done with a bs-config.js file, which requires the module.exports = { ... }; syntax:

module.exports = {
  server: {
    middleware: {
      // overrides the second middleware default with new settings
      1: require('connect-history-api-fallback')({
        index: '/index.html',
        verbose: true,
      }),
    },
  },
};

The bs-config.js file may also export a function that receives the lite-server Browsersync instance as its only argument. While not required, the return value of this function will be used to extend the default lite-server configuration.

module.exports = function (bs) {
  return {
    server: {
      middleware: {
        // overrides the second middleware default with new settings
        1: require('connect-history-api-fallback')({
          index: '/index.html',
          verbose: true,
        }),
      },
    },
  };
};

NOTE: Keep in mind that when using middleware overrides the specific middleware module must be installed in your project. For the above example, you'll need to do:

npm install connect-history-api-fallback --save-dev

...otherwise you'll get an error similar to:

Error: Cannot find module 'connect-history-api-fallback'

Another example: To remove one of the default middlewares, such as connect-logger, you can set it's array index to null:

module.exports = {
  server: {
    middleware: {
      0: null, // removes default `connect-logger` middleware
    },
  },
};

A list of the entire set of BrowserSync options can be found in its docs: http://www.browsersync.io/docs/options/

Testing

When using lite-server to run end to end tests, we may not want to log verbosely. We may also want to prevent the browser from opening. These options in the bs-config.js will silence all logging from lite-server:

  open: false
  logLevel: "silent",
  server: {
    middleware: {
      0: null
    }
  }

Known Issues

CSS with Angular 2 is embedded thus even though BrowserSync detects the file change to CSS, it does not inject the file via sockets. As a workaround, injectChanges defaults to false.