HTTP Service interface settings for WebClient are silently ignored

read-timeout config option is ignored for WEB_CLIENT client type
springboot-version: 4.0.2
java-version: 25

TestController - a mock remote server, sleeping for 10 seconds to simulate slow response

@RestController
@RequestMapping("/test")
public class TestController {

    @GetMapping
    public String test() throws InterruptedException {
        Thread.sleep(10000);
        return "Hello after 10 seconds";
    }
}

TestClient - http service client calling the mock server defined above

@HttpExchange("/test")
public interface TestClient {

    @GetExchange
    String test();
}

HttpServiceClientsConfiguration - importing TestClient with given group name + client type set to WEB_CLIENT

@Configuration
@ImportHttpServices(group = "test-group-name", types = TestClient.class, clientType = HttpServiceGroup.ClientType.WEB_CLIENT)
class HttpServiceClientsConfig {

}

Application - demo app simulating the request to the mock server

@SpringBootApplication
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @Bean
    ApplicationRunner applicationRunner(TestClient testClient) {
        return _ -> {
            System.out.println("Calling test client...");
            String result = testClient.test();
            System.out.println("Result: " + result);
        };
    }
}

application.yaml

spring:
  http:
    serviceclient:
      test-group-name:
        base-url: http://localhost:8080
        read-timeout: 5s

the read timeout is set to 5 seconds while the slow response of mock server takes 10 seconds. I'd expect some kind of exception on mock server request execution but the request is processed after 10 seconds without any exception.

I tried it with REST_CLIENT client type, I got an ResourceAccessException after 5 seconds which is a desired behaviour.

Start with the application.yaml configuration and reproduce the TestClient call using WEB_CLIENT, then compare it with the REST_CLIENT behavior described in the issue. Trace how the test-group-name read-timeout is applied to each client type. Done means a 10-second response triggers a timeout at about 5 seconds for WEB_CLIENT, as it does for REST_CLIENT.