files/en-us/web/api/windowsharedstorage/worklet/index.md
{{APIRef("Shared Storage API")}}{{deprecated_header}}
The worklet read-only property of the
{{domxref("WindowSharedStorage")}} interface contains the {{domxref("SharedStorageWorklet")}} instance representing the shared storage worklet for the current origin.
SharedStorageWorklet contains the {{domxref("Worklet.addModule", "addModule()")}} method, which is used to add a module to the shared storage worklet.
A {{domxref("SharedStorageWorklet")}} object.
// Randomly assigns a user to a group 0 or 1
function getExperimentGroup() {
return Math.round(Math.random());
}
async function injectContent() {
// Add the module to the shared storage worklet
await window.sharedStorage.worklet.addModule("ab-testing-worklet.js");
// Assign user to a random group (0 or 1) and store it in shared storage
window.sharedStorage.set("ab-testing-group", getExperimentGroup(), {
ignoreIfPresent: true,
});
// Run the URL selection operation
const fencedFrameConfig = await window.sharedStorage.selectURL(
"ab-testing",
[
{ url: `https://your-server.example/content/default-content.html` },
{ url: `https://your-server.example/content/experiment-content-a.html` },
],
{
resolveToConfig: true,
},
);
// Render the chosen URL into a fenced frame
document.getElementById("content-slot").config = fencedFrameConfig;
}
injectContent();
See the Shared Storage API landing page for a walkthrough of this example and for links to other examples.
{{Specifications}}
{{Compat}}