PushManager: subscribe() method

The subscribe() method of the PushManager interface subscribes to a push service.

It returns a Promise that resolves to a PushSubscription object containing details of a push subscription. A new push subscription is created if the current service worker does not have an existing subscription.

Syntax

subscribe(options)

Parameters

options Optional

An object containing optional configuration parameters. It can have the following properties:

userVisibleOnly

A boolean indicating that the returned push subscription will only be used for messages whose effect is made visible to the user.

applicationServerKey

A Base64-encoded string or ArrayBuffer containing an ECDSA P-256 public key that the push server will use to authenticate your application server. If specified, all messages from your application server must use the VAPID authentication scheme, and include a JWT signed with the corresponding private key. This key IS NOT the same ECDH key that you use to encrypt the data. For more information, see "Using VAPID with WebPush".

Note: This parameter is required in some browsers like Chrome and Edge. They will reject the Promise if userVisibleOnly is not set to true.

Return value

A Promise that resolves to a PushSubscription object.

Examples

this.onpush = (event) => {
  console.log(event.data);
  // From here we can write the data to IndexedDB, send it to any open
  // windows, display a notification, etc.
};

navigator.serviceWorker.register("serviceworker.js");

// Use serviceWorker.ready to ensure that you can subscribe for push
navigator.serviceWorker.ready.then((serviceWorkerRegistration) => {
  const options = {
    userVisibleOnly: true,
    applicationServerKey,
  };
  serviceWorkerRegistration.pushManager.subscribe(options).then(
    (pushSubscription) => {
      console.log(pushSubscription.endpoint);
      // The push subscription details needed by the application
      // server are now available, and can be sent to it using,
      // for example, the fetch() API.
    },
    (error) => {
      // During development it often helps to log errors to the
      // console. In a production environment it might make sense to
      // also report information about errors back to the
      // application server.
      console.error(error);
    },
  );
});

Responding to user gestures

subscribe() calls should be done in response to a user gesture, such as clicking a button, for example:

btn.addEventListener("click", () => {
  serviceWorkerRegistration.pushManager
    .subscribe(options)
    .then((pushSubscription) => {
      // handle subscription
    });
});

This is not only best practice — you should not be spamming users with notifications they didn't agree to — but going forward browsers will explicitly disallow notifications not triggered in response to a user gesture. Firefox is already doing this from version 72, for example.

Specifications

Browser compatibility