snapshot of https://github.com/toeverything/AFFiNE.git (canary, 2026-09-16; blobs > 131072B omitted)

blocksuite/playground/apps/_common/sync/websocket/awareness.ts

@@ -0,0 +1,93 @@
+import type { AwarenessSource } from '@blocksuite/sync';
+import type { Awareness } from 'y-protocols/awareness';
+import {
+  applyAwarenessUpdate,
+  encodeAwarenessUpdate,
+} from 'y-protocols/awareness';
+
+import type { WebSocketMessage } from './types';
+
+type AwarenessChanges = Record<'added' | 'updated' | 'removed', number[]>;
+
+export class WebSocketAwarenessSource implements AwarenessSource {
+  private readonly _onAwareness = (
+    changes: AwarenessChanges,
+    origin: unknown
+  ) => {
+    if (origin === 'remote') return;
+
+    const changedClients = Object.values(changes).reduce((res, cur) =>
+      res.concat(cur)
+    );
+
+    if (!this.awareness) {
+      throw new Error('awareness is not found');
+    }
+    const update = encodeAwarenessUpdate(this.awareness, changedClients);
+    this.ws.send(
+      JSON.stringify({
+        channel: 'awareness',
+        payload: {
+          type: 'update',
+          update: Array.from(update),
+        },
+      } satisfies WebSocketMessage)
+    );
+  };
+
+  private readonly _onWebSocket = (event: MessageEvent<string>) => {
+    const data = JSON.parse(event.data) as WebSocketMessage;
+
+    if (data.channel !== 'awareness') return;
+    const { type } = data.payload;
+
+    if (type === 'update') {
+      const update = data.payload.update;
+      if (!this.awareness) {
+        throw new Error('awareness is not found');
+      }
+      applyAwarenessUpdate(this.awareness, new Uint8Array(update), 'remote');
+    }
+
+    if (type === 'connect') {
+      if (!this.awareness) {
+        throw new Error('awareness is not found');
+      }
+      this.ws.send(
+        JSON.stringify({
+          channel: 'awareness',
+          payload: {
+            type: 'update',
+            update: Array.from(
+              encodeAwarenessUpdate(this.awareness, [this.awareness.clientID])
+            ),
+          },
+        } satisfies WebSocketMessage)
+      );
+    }
+  };
+
+  awareness: Awareness | null = null;
+
+  constructor(readonly ws: WebSocket) {}
+
+  connect(awareness: Awareness): void {
+    this.awareness = awareness;
+    awareness.on('update', this._onAwareness);
+
+    this.ws.addEventListener('message', this._onWebSocket);
+    this.ws.send(
+      JSON.stringify({
+        channel: 'awareness',
+        payload: {
+          type: 'connect',
+        },
+      } satisfies WebSocketMessage)
+    );
+  }
+
+  disconnect(): void {
+    this.awareness?.off('update', this._onAwareness);
+    this.ws.close();
+  }
+}