Worklet: addModule() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2021.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The addModule() method of the Worklet interface loads the module in the given JavaScript file and adds it to the current Worklet.

Syntax

js
addModule(moduleURL)
addModule(moduleURL, options)

Parameters

moduleURL

A String containing the URL of a JavaScript file with the module to add.

options Optional

An object with any of the following options:

credentials

A Request.credentials value that indicates whether to send credentials (e.g., cookies and HTTP authentication) when loading the module. Can be one of "omit", "same-origin", or "include". Defaults to "same-origin". See also Request.credentials.

Return value

A Promise that resolves once the module from the given URL has been added. The promise doesn't return any value.

Exceptions

If addModule() fails, it rejects the promise, delivering one of the following errors to the rejection handler.

AbortError DOMException

The specified script is invalid or could not be loaded.

SyntaxError DOMException

The specified moduleURL is invalid.

Examples

AudioWorklet example

js
const audioCtx = new AudioContext();
const audioWorklet = audioCtx.audioWorklet;
audioWorklet.addModule("modules/bypassFilter.js", {
  credentials: "omit",
});

PaintWorklet example

js
CSS.paintWorklet.addModule(
  "https://mdn.github.io/houdini-examples/cssPaint/intro/worklets/hilite.js",
);

Once the script has been added to the paint worklet, the CSS paint() function can be used to include the image created by the worklet:

css
@supports (background-image: paint(id)) {
  h1 {
    background-image: paint(hollow-highlights, filled, 3px);
  }
}

Specifications

Specification

HTML
# dom-worklet-addmodule-dev

Browser compatibility

Enable JavaScript to view this browser compatibility table.

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Worklet
Instance methods
1. addModule()

Worklet: addModule() method

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