micronaut redirect httprequest to different service

Question

In micronaut there are declarative clients:

@Client("http://localhost:5000")
public interface ServiceB {

    @Get("/ping")
    HttpResponse ping(HttpRequest httpRequest);
}

In my controller class I want to redirect the incoming request to ServiceB

@Controller("/api")
public class ServiceA {

    @Inject
    private ServiceB serviceB;

    @Get("/ping)
    HttpResponse pingOtherService(HttpRequest httpRequest){
        return serviceB.ping(httpRequest)
    }

}

However it seems that ServiceB will never get the request because of the information encoded in the request. How can I forward the request from ServiceA to ServiceB ?

Anorgar · Accepted Answer · 2020-05-27T08:42:43.940

The client can't send and HttpRequest directly. He will build one from the parameters of the client.

I tried to send the request to redirect in the body of the client, but get a stack overflow error : jackson can't convert it to string.

You can't change the URI in the request to send it back unfortunatly, no HttpRequest implementation have a setter on the URI.

If you really want to send the full request (header, body, params...) you can try to configure a proxy.

Else, if you don't have to pass the full request, you can pass through the client what you need :

Client example:

@Client("http://localhost:8080/test")
public interface RedirectClient {

  @Get("/redirect")
  String redirect(@Header(value = "test") String header);

}

The controller :

@Slf4j
@Controller("/test")
public class RedirectController {

  @Inject
  private RedirectClient client;

  @Get
  public String redirect(HttpRequest request){
    log.info("headers : {}", request.getHeaders().findFirst("test"));
    return client.redirect(request.getHeaders().get("test"));
  }

  @Get("/redirect")
  public String hello(HttpRequest request){
    log.info("headers : {}", request.getHeaders().findFirst("test"));
    return "Hello from redirect";
  }
}

I did it for one header, but you can do it with a body (if not a GET method), for request params, and so on.

I think with that the client would be calling the `pingOtherService` method in `ServiceA` and you would be in an infinite loop there. I assumed from the question that `ServiceA` was was in 1 app and the client is supposed to be calling a different app. — Jeff Scott Brown, May 27 '20 at 01:03
You right, it's not about the URI but about the request that can't be passed with the client. I have edited the answer. — Anorgar, May 27 '20 at 08:43

micronaut redirect httprequest to different service

1 Answers1