Use server customizer for Eureka Jackson mappings in mock server

Possible after Boot addressed spring-projects/spring-boot#47798

Author: ryanjbaxter

spring-cloud-netflix-eureka-client/src/test/java/org/springframework/cloud/netflix/eureka/http/EurekaServerMockApplication.java

@@ -27,14 +27,14 @@
 import com.netflix.discovery.shared.Applications;
 
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.http.converter.autoconfigure.ServerHttpMessageConvertersCustomizer;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.Ordered;
 import org.springframework.core.annotation.Order;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
-import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
 import org.springframework.security.config.Customizer;
 import org.springframework.security.config.annotation.web.builders.HttpSecurity;
 import org.springframework.security.core.userdetails.User;
@@ -111,15 +111,6 @@ public class EurekaServerMockApplication {
 		.setNamespace("namespace1")
 		.build();
 
-	/**
-	 * Simulates Eureka Server own's serialization.
-	 * @return converter
-	 */
-	@Bean
-	public MappingJackson2HttpMessageConverter mappingJacksonHttpMessageConverter() {
-		return EurekaHttpClientUtils.mappingJacksonHttpMessageConverter();
-	}
-
 	@ResponseStatus(HttpStatus.OK)
 	@PostMapping("/apps/{appName}")
 	public void register(@PathVariable String appName, @RequestBody InstanceInfo instanceInfo) {
@@ -189,6 +180,17 @@ public InstanceInfo getInstance(@PathVariable(required = false) String appName,
 		return INFO;
 	}
 
+	/*
+	 * Use this customizer to make sure we use the Jackson mappings for the Eureka server
+	 */
+	@Bean
+	@Order
+	ServerHttpMessageConvertersCustomizer customServerConvertersCustomizer() {
+		return builder -> {
+			builder.jsonMessageConverter(EurekaHttpClientUtils.mappingJacksonHttpMessageConverter());
+		};
+	}
+
 	@Configuration(proxyBeanMethods = false)
 	@Order(Ordered.HIGHEST_PRECEDENCE)
 	protected static class TestSecurityConfiguration {

spring-cloud-netflix-eureka-client/src/test/java/org/springframework/cloud/netflix/eureka/http/WebClientEurekaHttpClientTests.java

@@ -34,14 +34,7 @@
  */
 @SpringBootTest(classes = EurekaServerMockApplication.class,
 		properties = { "debug=true", "security.basic.enabled=true", "eureka.client.webclient.enabled=true",
-				"eureka.client.fetch-registry=false", "eureka.client.register-with-eureka=false",
-				// spring.http.converters.preferred-json-mapper=jackson2 is only necessary
-				// to make the
-				// mock Eureka Server used in this test to work
-				// TODO we can likely remove this once this Boot issue is fixed post
-				// 2025.1.0-RC1:
-				// https://github.com/spring-projects/spring-boot/issues/47798
-				"spring.http.converters.preferred-json-mapper=jackson2" },
+				"eureka.client.fetch-registry=false", "eureka.client.register-with-eureka=false" },
 		webEnvironment = WebEnvironment.RANDOM_PORT)
 @DirtiesContext
 class WebClientEurekaHttpClientTests extends AbstractEurekaHttpClientTests {