feat(microservices): expose transport server getter

packages/common/index.ts

@@ -32,6 +32,7 @@ export {
   INestApplication,
   INestApplicationContext,
   INestMicroservice,
+  ITransportServer,
   InjectionToken,
   IntrospectionResult,
   MessageEvent,

packages/common/interfaces/index.ts

@@ -18,6 +18,7 @@ export * from './http/index.js';
 export * from './injectable.interface.js';
 export * from './microservices/nest-hybrid-application-options.interface.js';
 export * from './microservices/pre-request-hook.interface.js';
+export * from './microservices/transport-server.interface.js';
 export * from './middleware/index.js';
 export * from './modules/index.js';
 export * from './nest-application-context.interface.js';

packages/common/interfaces/microservices/transport-server.interface.ts

@@ -0,0 +1,19 @@
+/**
+ * Interface describing the shape of a transport server.
+ * Used as the return type of `getTransportServer()` to provide
+ * autocomplete without creating circular dependencies.
+ *
+ * @publicApi
+ */
+export interface ITransportServer {
+  /**
+   * Starts the transport server.
+   * @param callback Function to be called upon initialization
+   */
+  listen(callback: (...optionalParams: unknown[]) => any): any;
+
+  /**
+   * Closes the transport server (stops listening on port/connection).
+   */
+  close(): any;
+}

packages/common/interfaces/nest-microservice.interface.ts

@@ -3,6 +3,7 @@ import { ExceptionFilter } from './exceptions/exception-filter.interface.js';
 import { CanActivate } from './features/can-activate.interface.js';
 import { NestInterceptor } from './features/nest-interceptor.interface.js';
 import { PipeTransform } from './features/pipe-transform.interface.js';
+import { ITransportServer } from './microservices/transport-server.interface.js';
 import { PreRequestHook } from './microservices/pre-request-hook.interface.js';
 import { INestApplicationContext } from './nest-application-context.interface.js';
 import { WebSocketAdapter } from './websockets/web-socket-adapter.interface.js';
@@ -99,4 +100,11 @@ export interface INestMicroservice extends INestApplicationContext {
    * or a group of servers if there are more than one.
    */
   unwrap<T>(): T;
+
+  /**
+   * Returns the underlying transport server instance.
+   * Use this to close only the transport (port/connection) without
+   * triggering the full application shutdown lifecycle.
+   */
+  getTransportServer(): ITransportServer;
 }

packages/microservices/nest-microservice.ts

@@ -2,6 +2,7 @@ import type {
   CanActivate,
   ExceptionFilter,
   INestMicroservice,
+  ITransportServer,
   NestInterceptor,
   PipeTransform,
   PreRequestHook,
@@ -359,6 +360,15 @@ export class NestMicroservice
     throw new Error('"unwrap" method not supported by the underlying server');
   }
 
+  /**
+   * Returns the underlying transport server instance.
+   * Use this to close only the transport (port/connection) without
+   * triggering the full application shutdown lifecycle.
+   */
+  public getTransportServer(): ITransportServer {
+    return this.serverInstance;
+  }
+
   protected async closeApplication(): Promise<any> {
     this.socketModule && (await this.socketModule.close());
     this.microservicesModule && (await this.microservicesModule.close());

packages/microservices/server/server.ts

@@ -38,7 +38,7 @@ import {
 import { ConsumerSerializer } from '../interfaces/serializer.interface.js';
 import { IdentitySerializer } from '../serializers/identity.serializer.js';
 import { transformPatternToRoute } from '../utils/index.js';
-import { Logger, type LoggerService } from '@nestjs/common';
+import { ITransportServer, Logger, type LoggerService } from '@nestjs/common';
 import { loadPackage, loadPackageSync } from '@nestjs/common/internal';
 
 /**
@@ -47,7 +47,7 @@ import { loadPackage, loadPackageSync } from '@nestjs/common/internal';
 export abstract class Server<
   EventsMap extends Record<string, Function> = Record<string, Function>,
   Status extends string = string,
-> {
+> implements ITransportServer {
   /**
    * Unique transport identifier.
    */

packages/microservices/test/nest-microservice.spec.ts

@@ -214,4 +214,22 @@ describe('NestMicroservice', () => {
       expect(result).toBe(instance);
     });
   });
+
+  it('should return the transport server instance via getTransportServer()', () => {
+    const strategy = new (class extends Server {
+      listen = vi.fn();
+      close = vi.fn();
+      on = vi.fn();
+      unwrap = vi.fn();
+    })();
+
+    const instance = new NestMicroservice(
+      mockContainer,
+      { strategy },
+      mockGraphInspector,
+      mockAppConfig,
+    );
+
+    expect(instance.getTransportServer()).toBe(strategy);
+  });
 });