polls socket adapter init

server/src/socket-io-adapter.ts

@@ -0,0 +1,22 @@
+import { INestApplicationContext, Logger } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import { IoAdapter } from '@nestjs/platform-socket.io';
+import { ServerOptions } from 'socket.io';
+
+export class SocketIOAdapter extends IoAdapter {
+  private readonly logger = new Logger(SocketIOAdapter.name);
+  constructor(
+    private app: INestApplicationContext,
+    private configService: ConfigService,
+  ) {
+    super(app);
+  }
+
+  createIOServer(port: number, options?: ServerOptions) {
+    const clientPort = parseInt(this.configService.get('CLIENT_PORT'));
+
+    const cors = {
+      origin: [`http://localhost:${clientPort}`],
+    };
+  }
+}