Webpack WebExtension Plugin

Webpack plugin that compiles web-extension manifest.json files and adds smart auto reload.

If you are looking for a simple CLI tool that utilizes this checkout https://github.com/webextension-toolbox/webextension-toolbox

What does it do?

• Autoreload extensions via websockets
• Use vendor prefixes in manifest properties
• ENV replacement in manifest values
• Validates some manifest.json fields

Install

$ npm i @webextension-toolbox/webextension-toolbox

Usage

import WebextensionPlugin from "@webextension-toolbox/webpack-webextension-plugin";

const config = {
  plugins: [
    new WebextensionPlugin({
      vendor: "chrome",
    }),
  ],
};

API

new WebextensionPlugin([options])

Add result to webpack plugins to initialize.

options

Type: Object

Any of the options below.

vendor

Type: String Default: chrome Any of: chrome, opera, firefox, edge, safari

Used for vendor prefixing in the manifest.json. More infos regarding this can be found below.

port

Type: Integer Default: 35729

Specify the listening port for the webstocket development server.

autoreload

Type: Boolean Default: true

Enables auto reload. If not specified will be enabled when using webpacks watch mode.

quiet

Type: Boolean Default: false

Disable plugin logging.

reconnectTime

Type: Integer Default: 3000

Specify the reconnect time to the development server from the extension side.

manifestDefaults

Type: Object Default: {}

Allows you to define defaults for the manifest.json file.

skipManifestValidation

Type: Boolean Default: false

Skip Manifest Validation

FAQ

How does smart autoreload work?

We create/extend a background page or service worker in the extension with a websockets client if autoreload is true the webpack is watching, that connects to our custom websocket server.

As soon as a specific files changes the client checks how to reload the extension:

• if manifest.json change → full reload
• if manifest.json dependencies change → full reload
• if _locales change → full reload
• else reload current tab & all extension views

What are vendor prefixed manifest keys?

Vendor prefixed manifest keys allow you to write one manifest.json for multible vendors.

{
  "__chrome__name": "SuperChrome",
  "__firefox__name": "SuperFox",
  "__edge__name": "SuperEdge",
  "__opera__name": "SuperOpera",
  "__safari__name": "SuperSafari"
}

if the vendor is chrome this compiles to:

{
  "name": "SuperChrome",
}

Add keys to multiple vendors by seperating them with | in the prefix

{
  __chrome|opera__name: "SuperBlink"
}

if the vendor is chrome or opera, this compiles to:

{
  "name": "SuperBlink"
}

Environment Variable Replacement in Manifest

{
  "name": "__MY_ENV_VARIABLE__",
}

Would be replaced with the value of process.env.MY_ENV_VARIABLE

Why are you not using mozillas web-ext package?

• webpack-webextension-plugin should work for every browser in the same way.
• web-ext only works with Chrome and Firefox. You should definitely still check it out.

Links

• generator-web-extension
• webextension-toolbox

License

Copyright 2018-2022 Henrik Wenz

This project is free software released under the MIT license.