Notifications Worker served at notify.rec.djdevin.net. Ported from the C# NotifyController / NotificationsHub / NotificationService, which host a SignalR hub at /hub/v1.

The hub is implemented as a Durable Object (NotificationsHub) speaking the SignalR JSON Hub Protocol over a hibernatable WebSocket. A single global DO instance plays the role of the C# static dictionaries (one shared process across all connections).

Endpoints

POST /hub/v1/negotiate — SignalR negotiation. Returns a connectionId / connectionToken and advertises the WebSocket transport. The token is passed back as ?id= on the WebSocket connect.
GET /hub/v1 (WebSocket upgrade) — the hub. Forwarded to the Durable Object. Non-upgrade requests get 426.
POST /internal/notify — { playerId, notificationType, data? }. Send to a player's connections, queueing if they're offline. Unauthenticated; internal use only (TODO: protect).
POST /internal/broadcast — { notificationType, data? }. Send to every connected client.

Hub protocol

Client POST /hub/v1/negotiate, then opens a WebSocket to /hub/v1?id=<token>.
Handshake: client sends {"protocol":"json","version":1}␞, server replies {}␞ (␞ = record separator 0x1e).
Server immediately sends the OnConnect invocation (mirrors the C# OnConnectedAsync).
Client→server invocations:
- SubscribeToPlayers({ playerIds }) — replaces this connection's subscriptions and flushes any queued notifications for those players.
- GetSubscriptions() → completion with the subscribed player id array.
Server→client: Notification invocations carrying a JSON string { Id: <PushNotificationId>, Msg: { ... } }.
Pings (type 6) are echoed.

State

Held in the DO's SQLite so it survives hibernation:

subscriptions(connectionId, playerId) — serves both the connection→players and player→connections lookups from the C#.
pending(id, playerId, payload) — per-player queue delivered once the player subscribes.

A connection's rows are removed on webSocketClose (the C# OnDisconnected).

TODO before production

Authenticate the /internal/* endpoints (or move them to a service binding / RPC reachable only by other workers).
Wire the real callers (relationships, gifts, storefront, events, chat, …) to push through notifyPlayer / broadcast.
Consider server-initiated keepalive pings if clients rely on them.