Expose particular REST controller on specific port using Spring Webflux

[amolai]

Working on a spring boot based application and using spring webflux, we are exposing 3 ports

1. server.port

2. management.server.port (actuator) and are planning to expose another port called as admin port.

We want to expose a specific REST controller on this admin port which will be private. This api will provide all the admin level configuration and will not be available publicly to the user.

Note: We don't want to expose api on actuator port. Need to open a new port.

Using the following code to open a new port by starting a new server instance.

`@Configuration
public class NettyServerForAdminPort {

@Value("${admin.port}")
private Integer adminPort;

@Autowired
HttpHandler httpHandler;

WebServer http;

@PostConstruct
public void start() {
  ReactiveWebServerFactory factory = new NettyReactiveWebServerFactory(8081);
  this.http = factory.getWebServer(this.httpHandler);
  this.http.start();
}

@PreDestroy
public void stop() {
  this.http.stop();
}

}`

Spring boot, webflux doesn't provide an out of box solution for this, can this be achieved using RouterFunction ??
Any insights here would be helpful.

Thank you