build: update to spring boot 4.1

pom.xml

@@ -6,7 +6,7 @@
   <parent>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-parent</artifactId>
-    <version>3.5.8</version>
+    <version>4.1.0</version>
   </parent>
   <groupId>com.obsidiandynamics.kafdrop</groupId>
   <artifactId>kafdrop</artifactId>
@@ -156,16 +156,12 @@
     <!-- Spring Boot -->
     <dependency>
       <groupId>org.springframework.boot</groupId>
-      <artifactId>spring-boot-starter-web</artifactId>
+      <artifactId>spring-boot-starter-webmvc</artifactId>
       <exclusions>
         <exclusion>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-logging</artifactId>
         </exclusion>
-        <exclusion>
-          <groupId>org.springframework.boot</groupId>
-          <artifactId>spring-boot-starter-tomcat</artifactId>
-        </exclusion>
       </exclusions>
     </dependency>
     <dependency>
@@ -176,10 +172,6 @@
       <groupId>org.springframework.kafka</groupId>
       <artifactId>spring-kafka</artifactId>
     </dependency>
-    <dependency>
-      <groupId>org.springframework.boot</groupId>
-      <artifactId>spring-boot-starter-undertow</artifactId>
-    </dependency>
     <dependency>
       <groupId>org.springframework.boot</groupId>
       <artifactId>spring-boot-starter-freemarker</artifactId>
@@ -211,7 +203,7 @@
     <dependency>
       <groupId>org.springdoc</groupId>
       <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
-      <version>2.8.14</version>
+      <version>3.0.3</version>
       <exclusions>
         <exclusion>
           <groupId>org.apache.commons</groupId>
@@ -226,6 +218,16 @@
       <artifactId>spring-boot-starter-test</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-restclient</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-resttestclient</artifactId>
+      <scope>test</scope>
+    </dependency>
 
     <!-- Testcontainers -->
     <dependency>
@@ -354,7 +356,7 @@
       <plugin>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-maven-plugin</artifactId>
-        <version>3.5.8</version>
+        <version>4.1.0</version>
         <configuration>
           <mainClass>${start.class}</mainClass>
           <layout>ZIP</layout>

src/main/java/kafdrop/Kafdrop.java

@@ -18,30 +18,25 @@
 
 package kafdrop;
 
-import com.google.common.base.Strings;
-import io.undertow.server.DefaultByteBufferPool;
-import io.undertow.server.HandlerWrapper;
-import io.undertow.server.HttpHandler;
-import io.undertow.server.handlers.DisallowedMethodsHandler;
-import io.undertow.util.HttpString;
-import io.undertow.websockets.jsr.WebSocketDeploymentInfo;
+import jakarta.servlet.FilterChain;
+import jakarta.servlet.ServletException;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
 import kafdrop.config.ini.IniFilePropertySource;
 import kafdrop.config.ini.IniFileReader;
+import org.jspecify.annotations.NonNull;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.boot.Banner.Mode;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.boot.builder.SpringApplicationBuilder;
 import org.springframework.boot.context.event.ApplicationEnvironmentPreparedEvent;
-import org.springframework.boot.web.embedded.undertow.UndertowDeploymentInfoCustomizer;
-import org.springframework.boot.web.embedded.undertow.UndertowServletWebServerFactory;
-import org.springframework.boot.web.server.WebServerFactoryCustomizer;
+import org.springframework.web.filter.OncePerRequestFilter;
+import org.springframework.boot.web.servlet.FilterRegistrationBean;
 import org.springframework.context.ApplicationListener;
 import org.springframework.context.annotation.Bean;
 import org.springframework.core.Ordered;
 import org.springframework.core.env.Environment;
-import org.springframework.web.servlet.config.annotation.ContentNegotiationConfigurer;
-import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
 
 import java.io.File;
 import java.io.FileInputStream;
@@ -68,36 +63,22 @@ public static SpringApplicationBuilder createApplicationBuilder() {
   }
 
   @Bean
-  public WebServerFactoryCustomizer<UndertowServletWebServerFactory> deploymentCustomizer() {
-    return factory -> {
-      final UndertowDeploymentInfoCustomizer customizer = deploymentInfo -> {
-        var inf = new WebSocketDeploymentInfo();
-        inf.setBuffers(new DefaultByteBufferPool(false, 64));
-        deploymentInfo.addServletContextAttribute(WebSocketDeploymentInfo.ATTRIBUTE_NAME, inf);
-        // see https://stackoverflow.com/a/54129696
-        deploymentInfo.addInitialHandlerChainWrapper(new HandlerWrapper() {
-          @Override
-          public HttpHandler wrap(HttpHandler handler) {
-            HttpString[] disallowedHttpMethods = {
-              HttpString.tryFromString("TRACE"),
-              HttpString.tryFromString("TRACK")
-            };
-            return new DisallowedMethodsHandler(handler, disallowedHttpMethods);
-          }
-        });
-      };
-      factory.addDeploymentInfoCustomizers(customizer);
-    };
-  }
-
-  @Bean
-  public WebMvcConfigurer webConfig() {
-    return new WebMvcConfigurer() {
+  public FilterRegistrationBean<OncePerRequestFilter> blockTrackFilter() {
+    FilterRegistrationBean<OncePerRequestFilter> registration = new FilterRegistrationBean<>();
+    registration.setOrder(Ordered.HIGHEST_PRECEDENCE);
+    registration.setFilter(new OncePerRequestFilter() {
       @Override
-      public void configureContentNegotiation(ContentNegotiationConfigurer configurer) {
-        configurer.favorPathExtension(false);
+      protected void doFilterInternal(@NonNull HttpServletRequest request, @NonNull HttpServletResponse response,
+                                      @NonNull FilterChain filterChain) throws ServletException, IOException {
+        String method = request.getMethod();
+        if ("TRACK".equals(method)) {
+          response.sendError(HttpServletResponse.SC_METHOD_NOT_ALLOWED, "TRACK method is not allowed");
+          return;
+        }
+        filterChain.doFilter(request, response);
       }
-    };
+    });
+    return registration;
   }
 
   private static final class LoggingConfigurationListener

src/main/java/kafdrop/config/HealthCheckConfiguration.java

@@ -18,17 +18,18 @@
 
 package kafdrop.config;
 
-import org.springframework.boot.actuate.health.Health;
-import org.springframework.boot.actuate.health.HealthEndpoint;
-import org.springframework.boot.actuate.health.Status;
+import org.springframework.boot.health.actuate.endpoint.CompositeHealthDescriptor;
+import org.springframework.boot.health.actuate.endpoint.HealthDescriptor;
+import org.springframework.boot.health.actuate.endpoint.HealthEndpoint;
+import org.springframework.boot.health.actuate.endpoint.IndicatedHealthDescriptor;
+import org.springframework.boot.health.contributor.Status;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.jmx.export.annotation.ManagedAttribute;
 import org.springframework.jmx.export.annotation.ManagedResource;
 import org.springframework.stereotype.Component;
 
 import java.util.LinkedHashMap;
 import java.util.Map;
-import java.util.stream.Collectors;
 
 @Configuration
 public class HealthCheckConfiguration {
@@ -43,28 +44,39 @@ public HealthCheck(HealthEndpoint healthEndpoint) {
 
     @ManagedAttribute
     public Map<String, Object> getHealth() {
-      final var health = (Health) healthEndpoint.health();
+      final var health = healthEndpoint.health();
       final var healthMap = new LinkedHashMap<String, Object>();
-      healthMap.put("status", getStatus(health));
-      healthMap.put("detail", getDetails(health.getDetails()));
+      healthMap.put("status", getStatus(health.getStatus()));
+      healthMap.put("detail", getDetails(health));
       return healthMap;
     }
 
-    private Map<String, Object> getDetails(Map<String, Object> details) {
-      return details.entrySet().stream()
-        .collect(Collectors.toMap(Map.Entry::getKey,
-          e -> {
-            final var health = (Health) e.getValue();
-            final var detail = new LinkedHashMap<String, Object>();
-            final var healthy = Status.UP.equals(health.getStatus());
-            detail.put("healthy", healthy);
-            detail.put("message", health.getDetails().toString());
-            return detail;
-          }));
+    private Map<String, Object> getDetails(HealthDescriptor healthDescriptor) {
+      if (healthDescriptor instanceof CompositeHealthDescriptor composite) {
+        final var result = new LinkedHashMap<String, Object>();
+        composite.getComponents().forEach((key, component) -> result.put(key, describeComponent(component)));
+        return result;
+      }
+      if (healthDescriptor instanceof IndicatedHealthDescriptor indicated) {
+
+        return indicated.getDetails();
+      }
+      return Map.of();
+    }
+
+    private Object describeComponent(HealthDescriptor component) {
+      if (component instanceof CompositeHealthDescriptor composite) {
+        return getDetails(composite);
+      }
+      final var detail = new LinkedHashMap<String, Object>();
+      detail.put("healthy", Status.UP.equals(component.getStatus()));
+      detail.put("message", component instanceof IndicatedHealthDescriptor indicated
+        ? indicated.getDetails().toString()
+        : component.getStatus().toString());
+      return detail;
     }
 
-    private String getStatus(Health health) {
-      final var status = health.getStatus();
+    private String getStatus(Status status) {
       if (Status.UP.equals(status) || Status.DOWN.equals(status)) {
         return status.toString();
       } else {

src/main/java/kafdrop/config/ObjectMapperConfig.java

@@ -1,19 +1,18 @@
 package kafdrop.config;
 
-import com.fasterxml.jackson.databind.ObjectMapper;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
-import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
+import tools.jackson.databind.json.JsonMapper;
 
 import java.util.TimeZone;
 
 @Configuration
 public class ObjectMapperConfig {
 
   @Bean
-  public ObjectMapper objectMapper(Jackson2ObjectMapperBuilder builder) {
+  public JsonMapper objectMapper(JsonMapper.Builder builder) {
     return builder
-      .timeZone(TimeZone.getDefault())
+      .defaultTimeZone(TimeZone.getDefault())
       .build();
   }
 }

src/main/java/kafdrop/controller/BasicErrorController.java

@@ -3,9 +3,9 @@
 import jakarta.servlet.http.HttpServletRequest;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
-import org.springframework.boot.autoconfigure.web.servlet.error.AbstractErrorController;
 import org.springframework.boot.web.error.ErrorAttributeOptions;
-import org.springframework.boot.web.servlet.error.ErrorAttributes;
+import org.springframework.boot.webmvc.autoconfigure.error.AbstractErrorController;
+import org.springframework.boot.webmvc.error.ErrorAttributes;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.servlet.ModelAndView;

src/main/java/kafdrop/service/KafkaHighLevelAdminClient.java

@@ -4,8 +4,8 @@
 import kafdrop.config.KafkaConfiguration;
 import org.apache.kafka.clients.admin.AdminClient;
 import org.apache.kafka.clients.admin.Config;
-import org.apache.kafka.clients.admin.ConsumerGroupListing;
 import org.apache.kafka.clients.admin.DeleteTopicsOptions;
+import org.apache.kafka.clients.admin.GroupListing;
 import org.apache.kafka.clients.admin.NewTopic;
 import org.apache.kafka.clients.consumer.ConsumerConfig;
 import org.apache.kafka.clients.consumer.OffsetAndMetadata;
@@ -84,13 +84,13 @@ ClusterDescription describeCluster() {
   }
 
   Set<String> listConsumerGroups() {
-    final Collection<ConsumerGroupListing> groupListing;
+    final Collection<GroupListing> groupListing;
     try {
-      groupListing = adminClient.listConsumerGroups().valid().get();
+      groupListing = adminClient.listGroups().valid().get();
     } catch (InterruptedException | ExecutionException e) {
       throw new KafkaAdminClientException(e);
     }
-    return groupListing.stream().map(ConsumerGroupListing::groupId).collect(Collectors.toSet());
+    return groupListing.stream().map(GroupListing::groupId).collect(Collectors.toSet());
   }
 
   Map<TopicPartition, OffsetAndMetadata> listConsumerGroupOffsetsIfAuthorized(String groupId) {

src/main/resources/application.yml

@@ -20,10 +20,9 @@ spring:
   jackson:
     deserialization:
       fail_on_unknown_properties: false
-      read_unknown_enum_values_as_null: true
-  mvc:
-    pathmatch:
-      matching-strategy: ant_path_matcher
+    datatype:
+      enum:
+        read_unknown_enum_values_as_null: true
 
 springdoc:
   enable-kotlin: false # Kafdrop does not use Kotlin; enabling it causes #803

src/test/java/kafdrop/KafdropTest.java

@@ -3,9 +3,10 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.resttestclient.TestRestTemplate;
+import org.springframework.boot.resttestclient.autoconfigure.AutoConfigureTestRestTemplate;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
-import org.springframework.boot.test.web.client.TestRestTemplate;
 import org.springframework.boot.test.web.server.LocalServerPort;
 import org.springframework.http.ResponseEntity;
 import org.springframework.test.context.junit.jupiter.SpringExtension;
@@ -18,6 +19,7 @@
 
 @ExtendWith(SpringExtension.class)
 @SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
+@AutoConfigureTestRestTemplate
 public class KafdropTest extends AbstractIntegrationTest {
 
   @LocalServerPort