feat: Add WebSocket functionality to server.

test/unit/server/WebSocketServerFactory.test.ts

@@ -0,0 +1,54 @@
+import type { Server } from 'http';
+import request from 'supertest';
+import WebSocket from 'ws';
+import { ExpressHttpServerFactory } from '../../../src/server/ExpressHttpServerFactory';
+import { HttpHandler } from '../../../src/server/HttpHandler';
+import type { HttpRequest } from '../../../src/server/HttpRequest';
+import type { HttpResponse } from '../../../src/server/HttpResponse';
+import { WebSocketHandler } from '../../../src/server/WebSocketHandler';
+import { WebSocketServerFactory } from '../../../src/server/WebSocketServerFactory';
+
+class SimpleHttpHandler extends HttpHandler {
+  public async handle(input: { request: HttpRequest; response: HttpResponse }): Promise<void> {
+    input.response.end('SimpleHttpHandler');
+  }
+}
+
+class SimpleWebSocketHandler extends WebSocketHandler {
+  public host: any;
+
+  public async handle(input: { webSocket: WebSocket; upgradeRequest: HttpRequest }): Promise<void> {
+    input.webSocket.send('SimpleWebSocketHandler');
+    input.webSocket.close();
+    this.host = input.upgradeRequest.headers.host;
+  }
+}
+
+describe('SimpleWebSocketHandler', (): void => {
+  let webSocketHandler: SimpleWebSocketHandler;
+  let server: Server;
+
+  beforeAll(async(): Promise<void> => {
+    const httpHandler = new SimpleHttpHandler();
+    webSocketHandler = new SimpleWebSocketHandler();
+    const httpServerFactory = new ExpressHttpServerFactory(httpHandler);
+    const webSocketServerFactory = new WebSocketServerFactory(httpServerFactory, webSocketHandler);
+    server = webSocketServerFactory.startServer(5555);
+  });
+
+  afterAll(async(): Promise<void> => {
+    server.close();
+  });
+
+  it('has a functioning HTTP interface.', async(): Promise<void> => {
+    const result = await request(server).get('/').expect('SimpleHttpHandler');
+    expect(result).toBeDefined();
+  });
+
+  it('has a functioning WebSockets interface.', async(): Promise<void> => {
+    const client = new WebSocket('ws://localhost:5555');
+    const text = await new Promise((resolve): any => client.on('message', resolve));
+    expect(text).toBe('SimpleWebSocketHandler');
+    expect(webSocketHandler.host).toBe('localhost:5555');
+  });
+});