Internal representation of a notification channel. Most of the fields are those defined in https://solidproject.org/TR/2022/notifications-protocol-20221231#notification-channel-data-model
We only support notification channels with a single topic.
The media type in which the receiver expects the notifications.
When the channel should stop existing, in milliseconds since epoch.
The unique identifier of the channel.
Internal value that we use to track when this channel last sent a notification.
The minimal time required between notifications, in milliseconds.
The resource receivers can use to establish a connection and receive notifications.
The resource on the receiver where notifications can be sent.
Can be used to identify the sender.
When the channel should start sending notifications, in milliseconds since epoch.
The state parameter sent by the receiver. This is used to send a notification when the channel is established and the topic resource has a different state.
The resource this channel sends notifications about.
The channel type.