# createWsServer \[Attach a Hub to WebSocket connections] `createWsServer(hub, { secret })` attaches a `Hub` to WebSocket connections. Call it once at startup; call `handleConnection` for every new socket. The `secret` is required — the same HMAC key `createSync` signs grants with, so the WS layer can verify them. ```ts import { createWsServer } from "rxfy-ws"; type ServerSocket = { send: (data: string) => void; on: (event: string, listener: (...args: unknown[]) => void) => void; }; function createWsServer(hub: Hub, options: { secret: string }): { handleConnection: (socket: ServerSocket) => void }; ``` `ServerSocket` is a structural type — the `ws` package's `WebSocket` satisfies it directly. Frameworks that wrap the underlying socket (Hono, Bun, etc.) need a thin adapter. When a `subscribe` frame arrives, the server verifies its grant — signature plus expiry — and, on success, subscribes the socket to the grant's channel plus the entity topics named in the frame. A frame whose grant is invalid or expired is dropped silently: no reply, no subscription (the client recovers by renewing or refetching). When the socket closes, all of its subscriptions are dropped. See [Grants](/framework/server/grants). ## Adapter pattern (Hono) The Hono bridge from `examples/vite-blog` shows the pattern: create an `EventEmitter` to act as the event bus, pass a `ServerSocket` literal to `handleConnection` on open, and relay `onMessage` / `onClose` events through the emitter. ```ts [server/ws.ts] import { EventEmitter } from "node:events"; import type { UpgradeWebSocket } from "hono/ws"; import { createWsServer } from "rxfy-ws"; import { hub, SECRET } from "./sync.js"; const wsServer = createWsServer(hub, { secret: SECRET }); export function liveRoute(upgradeWebSocket: UpgradeWebSocket) { return upgradeWebSocket(() => { const emitter = new EventEmitter(); return { onOpen(_evt: Event, ws: { send: (data: string) => void }) { wsServer.handleConnection({ send: (data: string) => ws.send(data), on: (event, cb) => emitter.on(event, cb), }); }, onMessage(evt: MessageEvent) { emitter.emit("message", evt.data); }, onClose() { emitter.emit("close"); }, }; }); } ``` The hub side of this wiring is covered in [createInMemoryHub](/framework/server/hub).