websocket cursor data broadcast

src/app.module.ts

@@ -5,6 +5,7 @@ import { AppService } from './app.service';
 import { UsersModule } from './users/users.module';
 import { AuthModule } from './auth/auth.module';
 import { DatabaseModule } from './database/database.module';
+import { WsModule } from './ws/ws.module';
 
 /**
  * Validates required environment variables.
@@ -51,6 +52,7 @@ function validateEnvironment(config: Record<string, any>): Record<string, any> {
     DatabaseModule, // Global database module for Prisma
     UsersModule,
     AuthModule,
+    WsModule,
   ],
   controllers: [AppController],
   providers: [AppService],

src/ws/state/state.gateway.spec.ts

@@ -0,0 +1,97 @@
+import { Test, TestingModule } from '@nestjs/testing';
+import { StateGateway } from './state.gateway';
+import { Socket } from 'socket.io';
+
+describe('StateGateway', () => {
+  let gateway: StateGateway;
+  let mockLoggerLog: jest.SpyInstance;
+  let mockLoggerDebug: jest.SpyInstance;
+  let mockServer: any;
+
+  beforeEach(async () => {
+    mockServer = {
+      sockets: {
+        sockets: {
+          size: 5,
+        },
+      },
+    };
+
+    const module: TestingModule = await Test.createTestingModule({
+      providers: [StateGateway],
+    }).compile();
+
+    gateway = module.get<StateGateway>(StateGateway);
+    gateway.io = mockServer;
+
+    // Spy on logger methods
+    mockLoggerLog = jest
+      // gateway is private in `state.gateway.ts` so we have to
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
+      .spyOn((gateway as any).logger, 'log')
+      .mockImplementation();
+    mockLoggerDebug = jest
+      // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
+      .spyOn((gateway as any).logger, 'debug')
+      .mockImplementation();
+  });
+
+  afterEach(() => {
+    jest.restoreAllMocks();
+  });
+
+  it('should be defined', () => {
+    expect(gateway).toBeDefined();
+  });
+
+  describe('afterInit', () => {
+    it('should log initialization message', () => {
+      gateway.afterInit();
+
+      expect(mockLoggerLog).toHaveBeenCalledWith('Initialized');
+    });
+  });
+
+  describe('handleConnection', () => {
+    it('should log client connection and number of connected clients', () => {
+      const mockClient = { id: 'client1' } as Socket;
+
+      gateway.handleConnection(mockClient);
+
+      expect(mockLoggerLog).toHaveBeenCalledWith(
+        `Client id: ${mockClient.id} connected`,
+      );
+      expect(mockLoggerDebug).toHaveBeenCalledWith(
+        'Number of connected clients: 5',
+      );
+    });
+  });
+
+  describe('handleDisconnect', () => {
+    it('should log client disconnection', () => {
+      const mockClient = { id: 'client1' } as Socket;
+
+      gateway.handleDisconnect(mockClient);
+
+      expect(mockLoggerLog).toHaveBeenCalledWith(
+        `Cliend id:${mockClient.id} disconnected`,
+      );
+    });
+  });
+
+  describe('handleCursorReportPosition', () => {
+    it('should log message received from client', () => {
+      const mockClient = { id: 'client1' } as Socket;
+      const data = { x: 100, y: 200 };
+
+      gateway.handleCursorReportPosition(mockClient, data);
+
+      expect(mockLoggerLog).toHaveBeenCalledWith(
+        `Message received from client id: ${mockClient.id}`,
+      );
+      expect(mockLoggerDebug).toHaveBeenCalledWith(
+        `Payload: ${JSON.stringify(data, null, 0)}`,
+      );
+    });
+  });
+});

src/ws/state/state.gateway.ts

@@ -0,0 +1,41 @@
+import { Logger } from '@nestjs/common';
+import {
+  OnGatewayConnection,
+  OnGatewayDisconnect,
+  OnGatewayInit,
+  SubscribeMessage,
+  WebSocketGateway,
+  WebSocketServer,
+} from '@nestjs/websockets';
+
+import { Server, Socket } from 'socket.io';
+
+@WebSocketGateway()
+export class StateGateway
+  implements OnGatewayInit, OnGatewayConnection, OnGatewayDisconnect
+{
+  private readonly logger = new Logger(StateGateway.name);
+
+  @WebSocketServer() io: Server;
+
+  afterInit() {
+    this.logger.log('Initialized');
+  }
+
+  handleConnection(client: Socket) {
+    const { sockets } = this.io.sockets;
+
+    this.logger.log(`Client id: ${client.id} connected`);
+    this.logger.debug(`Number of connected clients: ${sockets.size}`);
+  }
+
+  handleDisconnect(client: Socket) {
+    this.logger.log(`Cliend id:${client.id} disconnected`);
+  }
+
+  @SubscribeMessage('cursor-report-position')
+  handleCursorReportPosition(client: Socket, data: any) {
+    this.logger.log(`Message received from client id: ${client.id}`);
+    this.logger.debug(`Payload: ${JSON.stringify(data, null, 0)}`);
+  }
+}

src/ws/ws.module.ts

@@ -0,0 +1,7 @@
+import { Module } from '@nestjs/common';
+import { StateGateway } from './state/state.gateway';
+
+@Module({
+  providers: [StateGateway],
+})
+export class WsModule {}