Calling a non-reactive legacy service from reactive spring boot app?

Question

I am working heavily with a webflux based spring boot application. the problem I am facing, is that there is one service I have to call to, which is a traditional spring boot app, and is not reactive!

Here is an example endpoint which is close to the idea of said legacy system :

@RequestMapping(value = "/people/**", method = RequestMethod.GET)
public ResponseEntity<InputStreamResource> getPerson(HttpServletRequest request) {
    String pattern = (String) request.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE);
    String key = new AntPathMatcher().extractPathWithinPattern(pattern, request.getRequestURI());
    
        return personService.getPersonByKey(key);
    }

I KNOW I can't achieve true reactive goodness with this, is there a happy medium of non blocking and blocking I can achieve here?

Thanks

Answer 1

When you use WebClient to call the service from your Spring WebFlux application, then it will work in Reactive non blocking way. Meaning you can achieve true reactive goodness on your application. The thread will not be blocked until the upstream service returns the response.

Below is an example code for calling a service using WebClient:

WebClient webClient = WebClient.create("http://localhost:8080");

Mono<Person> result = webClient.get()
    .uri("/people/{id}")
    .retrieve()
    .bodyToMono(Person.class);