feat: Add support for WebSocketSubscription2021

test/unit/server/notifications/WebSocketSubscription2021/WebSocket2021Emitter.test.ts

@@ -0,0 +1,84 @@
+import { EventEmitter } from 'events';
+import type { WebSocket } from 'ws';
+import { BasicRepresentation } from '../../../../../src/http/representation/BasicRepresentation';
+import type {
+  SubscriptionInfo,
+} from '../../../../../src/server/notifications/SubscriptionStorage';
+import {
+  WebSocket2021Emitter,
+} from '../../../../../src/server/notifications/WebSocketSubscription2021/WebSocket2021Emitter';
+import type { SetMultiMap } from '../../../../../src/util/map/SetMultiMap';
+import { WrappedSetMultiMap } from '../../../../../src/util/map/WrappedSetMultiMap';
+
+describe('A WebSocket2021Emitter', (): void => {
+  const info: SubscriptionInfo = {
+    id: 'id',
+    topic: 'http://example.com/foo',
+    type: 'type',
+    features: {},
+    lastEmit: 0,
+  };
+
+  let webSocket: jest.Mocked<WebSocket>;
+  let socketMap: SetMultiMap<string, WebSocket>;
+  let emitter: WebSocket2021Emitter;
+
+  beforeEach(async(): Promise<void> => {
+    webSocket = new EventEmitter() as any;
+    webSocket.send = jest.fn();
+    webSocket.close = jest.fn();
+
+    socketMap = new WrappedSetMultiMap();
+
+    emitter = new WebSocket2021Emitter(socketMap);
+  });
+
+  it('emits notifications to the stored WebSockets.', async(): Promise<void> => {
+    socketMap.add(info.id, webSocket);
+
+    const representation = new BasicRepresentation('notification', 'text/plain');
+    await expect(emitter.handle({ info, representation })).resolves.toBeUndefined();
+    expect(webSocket.send).toHaveBeenCalledTimes(1);
+    expect(webSocket.send).toHaveBeenLastCalledWith('notification');
+  });
+
+  it('destroys the representation if there is no matching WebSocket.', async(): Promise<void> => {
+    const representation = new BasicRepresentation('notification', 'text/plain');
+    await expect(emitter.handle({ info, representation })).resolves.toBeUndefined();
+    expect(webSocket.send).toHaveBeenCalledTimes(0);
+    expect(representation.data.destroyed).toBe(true);
+  });
+
+  it('can send to multiple matching WebSockets.', async(): Promise<void> => {
+    const webSocket2: jest.Mocked<WebSocket> = new EventEmitter() as any;
+    webSocket2.send = jest.fn();
+
+    socketMap.add(info.id, webSocket);
+    socketMap.add(info.id, webSocket2);
+
+    const representation = new BasicRepresentation('notification', 'text/plain');
+    await expect(emitter.handle({ info, representation })).resolves.toBeUndefined();
+    expect(webSocket.send).toHaveBeenCalledTimes(1);
+    expect(webSocket.send).toHaveBeenLastCalledWith('notification');
+    expect(webSocket2.send).toHaveBeenCalledTimes(1);
+    expect(webSocket2.send).toHaveBeenLastCalledWith('notification');
+  });
+
+  it('only sends to the matching WebSockets.', async(): Promise<void> => {
+    const webSocket2: jest.Mocked<WebSocket> = new EventEmitter() as any;
+    webSocket2.send = jest.fn();
+    const info2: SubscriptionInfo = {
+      ...info,
+      id: 'other',
+    };
+
+    socketMap.add(info.id, webSocket);
+    socketMap.add(info2.id, webSocket2);
+
+    const representation = new BasicRepresentation('notification', 'text/plain');
+    await expect(emitter.handle({ info, representation })).resolves.toBeUndefined();
+    expect(webSocket.send).toHaveBeenCalledTimes(1);
+    expect(webSocket.send).toHaveBeenLastCalledWith('notification');
+    expect(webSocket2.send).toHaveBeenCalledTimes(0);
+  });
+});