SharedStorageWorkletGlobalScope: register() method

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The register() method of the SharedStorageWorkletGlobalScope interface registers an operation defined inside the current worklet module.

Syntax

js
register(name, operationCtor)

Parameters

name

A string representing the name with which you want to register the operation. When the operation is invoked (say via WindowSharedStorage.run() or WindowSharedStorage.selectURL()), this name is used to identify the operation you want to run.

operationCtor

A string representing the class name of the operation to be registered. This is the class constructor that is invoked when the operation is run.

Return value

None (undefined).

Exceptions

TypeError

Thrown if:

  • An operation has already been registered with the specified name.
  • The operationCtor is not a valid constructor.
  • The class does not contain a valid run() method.
  • The worklet module has not been added with SharedStorageWorklet.addModule().

Examples

js
// ab-testing-worklet.js
class SelectURLOperation {
  async run(urls, data) {
    // Read the user's experiment group from shared storage
    const experimentGroup = await this.sharedStorage.get("ab-testing-group");

    // Return the group number
    return experimentGroup;
  }
}

register("ab-testing", SelectURLOperation);

See the Shared Storage API landing page for a walkthrough of this example and for links to other examples.

Note: It is possible to define and register multiple operations in the same shared storage worklet module script with different names; see SharedStorageOperation for an example.

Specifications

Specification
Shared Storage API
# dom-sharedstorageworkletglobalscope-register

Browser compatibility

BCD tables only load in the browser

See also