webpush-channel-2023-flow.mmd

sequenceDiagram
  autonumber
  participant Browser Messaging Service as Browser Messaging Service (NR)
  participant PWA as PWA (DC & SC)
  participant Storage as Storage (RS)
  participant Subscription Service
  participant Notification Sender

  Note over PWA, Storage: Discovery (Solid)
  PWA ->>+ Storage: GET Storage Description
  Storage -->>- PWA: 200 OK includes Subscription Service description

  Note over PWA, Browser Messaging Service: Create Subscription (WebPush)
  PWA ->>+ Browser Messaging Service: Subscribe to Web Push Service
  Browser Messaging Service -->>- PWA: Web Push Subscription data 

  Note over PWA, Subscription Service: Establish Channel (Solid)
  PWA ->>+ Subscription Service: Submit subscription request to discovered subscription service via POST
  Subscription Service -->>- PWA: 201 CREATED

  Note over Browser Messaging Service, Notification Sender: Deliver Notifications on the channel (WebPush & Solid)
  loop for each notification
    Notification Sender -) Browser Messaging Service: Deliver notification (Solid & WebPush)
    Browser Messaging Service -) PWA: Deliver notification (WebPush)
  end

  Note over PWA, Subscription Service: Delete channel (Solid)
  PWA ->>+ Subscription Service: Unsubscribe (delete channel)
  Subscription Service -->>- PWA: 204 No Content

  Note over PWA, Browser Messaging Service: Cancel Subscription (WebPush)
  PWA ->>+ Browser Messaging Service: Unsubscribe (delete subscription)