The delivery type of the subscription. Valid values are: "fetch" or "webhook".

Fetch-based subscriptions are consumed at your discretion by creating and maintaining a position value which is used to query your notifications for a subscription from the "mailbox" store. See the position and fetch APIs for more information.

Webhook-based subscriptions allow registering an API endpoint under your control to receive HTTPS calls informing about new notifications becoming available in the "mailbox" store. Calls to your webhook API endpoint only inform about new notifications and do not contain notification details. Consuming notifications is still done at your discretion through the same means as with fetch-based subscriptions. The webhook enables "listening" for arriving notifications in your subscriptions' mailbox and fetching notifications on-demand when they become available instead of having to speculatively query the fetch API at regular intervals.

The desired domain to subscribe for notifications which matches the specified event types. Please note that all event types you subscribe to must support the chosen domain.

The list of event types to subscribe to.

Defines webhook related properties.