Endpoints at Reactive routes require a prefix "/" but @RequestMapping and others works even without it.

[CODINGSAINT]

Affects: <Spring Framework 5>

---

If we have use @GetMapping ("hello") or @GetMapping("/hello") both works seamlessly .Example: -

@GetMapping("user/{userId}")
public Optional<User> getUser(@PathVariable("userId") Long id) {
	logger.info(" User id {}", id);
	return userRepository.findById(id);
}

With Reactive Routes it is not same, it accepts only with prefix "/" which is counter intuitive. Example : -

@Bean
    public RouterFunction userRoutes() {
        return RouterFunctions.route(
                RequestPredicates.GET("/users"), userHandler::getAll)
                .andRoute(RequestPredicates.POST("/user"), userHandler::add)
                .andRoute(RequestPredicates.PUT("/user"), userHandler::update)
                .andRoute(RequestPredicates.GET("/user/{id}"), userHandler::get)
                .andRoute(RequestPredicates.DELETE("/user/{id}"), userHandler::delete);
    }

It might not be a bug but certainly can be an enhancement.

[StevenPG]

Can you reproduce this? Looking through the source, it seems the missing / is accounted for in the 5.2.0 release tag. (https://github.com/spring-projects/spring-framework/blob/v5.2.0.RELEASE/spring-webflux/src/main/java/org/springframework/web/reactive/function/server/RequestPredicates.java)

public static RequestPredicate POST(String pattern) {
	return method(HttpMethod.POST).and(path(pattern));
}
// and
public static RequestPredicate path(String pattern) {
	Assert.notNull(pattern, "'pattern' must not be null");
	if (!pattern.isEmpty() && !pattern.startsWith("/")) {
		pattern = "/" + pattern;
	}
	return pathPredicates(DEFAULT_PATTERN_PARSER).apply(pattern);
}

[rstoyanchev]

Resolving as duplicate of #22795.