Handle Kafka servers as strings and rely on Kafka's parsing

Closes gh-34770

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/kafka/KafkaAutoConfiguration.java

@@ -18,7 +18,6 @@ package org.springframework.boot.autoconfigure.kafka;
 
 import java.io.IOException;
 import java.time.Duration;
-import java.util.List;
 import java.util.Map;
 
 import org.apache.kafka.clients.CommonClientConfigs;
@@ -32,7 +31,6 @@ import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnSingleCandidate;
-import org.springframework.boot.autoconfigure.kafka.KafkaConnectionDetails.Node;
 import org.springframework.boot.autoconfigure.kafka.KafkaProperties.Jaas;
 import org.springframework.boot.autoconfigure.kafka.KafkaProperties.Retry.Topic;
 import org.springframework.boot.context.properties.EnableConfigurationProperties;
@@ -190,8 +188,7 @@ public class KafkaAutoConfiguration {
 
 	private void applyKafkaConnectionDetailsForConsumer(Map<String, Object> properties,
 			KafkaConnectionDetails connectionDetails) {
-		properties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG,
+		properties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, connectionDetails.getConsumerBootstrapServers());
-				nodesToStringList(connectionDetails.getConsumerBootstrapNodes()));
 		if (!(connectionDetails instanceof PropertiesKafkaConnectionDetails)) {
 			properties.put(CommonClientConfigs.SECURITY_PROTOCOL_CONFIG, "PLAINTEXT");
 		}
@@ -199,8 +196,7 @@ public class KafkaAutoConfiguration {
 
 	private void applyKafkaConnectionDetailsForProducer(Map<String, Object> properties,
 			KafkaConnectionDetails connectionDetails) {
-		properties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,
+		properties.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, connectionDetails.getProducerBootstrapServers());
-				nodesToStringList(connectionDetails.getProducerBootstrapNodes()));
 		if (!(connectionDetails instanceof PropertiesKafkaConnectionDetails)) {
 			properties.put(CommonClientConfigs.SECURITY_PROTOCOL_CONFIG, "PLAINTEXT");
 		}
@@ -208,17 +204,12 @@ public class KafkaAutoConfiguration {
 
 	private void applyKafkaConnectionDetailsForAdmin(Map<String, Object> properties,
 			KafkaConnectionDetails connectionDetails) {
-		properties.put(CommonClientConfigs.BOOTSTRAP_SERVERS_CONFIG,
+		properties.put(CommonClientConfigs.BOOTSTRAP_SERVERS_CONFIG, connectionDetails.getAdminBootstrapNodes());
-				nodesToStringList(connectionDetails.getAdminBootstrapNodes()));
 		if (!(connectionDetails instanceof PropertiesKafkaConnectionDetails)) {
 			properties.put(CommonClientConfigs.SECURITY_PROTOCOL_CONFIG, "PLAINTEXT");
 		}
 	}
 
-	private List<String> nodesToStringList(List<Node> nodes) {
-		return nodes.stream().map((node) -> node.host() + ":" + node.port()).toList();
-	}
-
 	private static void setBackOffPolicy(RetryTopicConfigurationBuilder builder, Topic retryTopic) {
 		long delay = (retryTopic.getDelay() != null) ? retryTopic.getDelay().toMillis() : 0;
 		if (delay > 0) {

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/kafka/KafkaConnectionDetails.java

@@ -34,48 +34,38 @@ public interface KafkaConnectionDetails extends ConnectionDetails {
 	 * Returns the list of bootstrap nodes.
 	 * @return the list of bootstrap nodes
 	 */
-	List<Node> getBootstrapNodes();
+	List<String> getBootstrapServers();
 
 	/**
 	 * Returns the list of bootstrap nodes used for consumers.
 	 * @return the list of bootstrap nodes used for consumers
 	 */
-	default List<Node> getConsumerBootstrapNodes() {
+	default List<String> getConsumerBootstrapServers() {
-		return getBootstrapNodes();
+		return getBootstrapServers();
 	}
 
 	/**
 	 * Returns the list of bootstrap nodes used for producers.
 	 * @return the list of bootstrap nodes used for producers
 	 */
-	default List<Node> getProducerBootstrapNodes() {
+	default List<String> getProducerBootstrapServers() {
-		return getBootstrapNodes();
+		return getBootstrapServers();
 	}
 
 	/**
 	 * Returns the list of bootstrap nodes used for the admin.
 	 * @return the list of bootstrap nodes used for the admin
 	 */
-	default List<Node> getAdminBootstrapNodes() {
+	default List<String> getAdminBootstrapNodes() {
-		return getBootstrapNodes();
+		return getBootstrapServers();
 	}
 
 	/**
 	 * Returns the list of bootstrap nodes used for Kafka Streams.
 	 * @return the list of bootstrap nodes used for Kafka Streams
 	 */
-	default List<Node> getStreamsBootstrapNodes() {
+	default List<String> getStreamsBootstrapServers() {
-		return getBootstrapNodes();
+		return getBootstrapServers();
-	}
-
-	/**
-	 * A Kafka node.
-	 *
-	 * @param host the hostname
-	 * @param port the port
-	 */
-	record Node(String host, int port) {
-
 	}
 
 }

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/kafka/KafkaStreamsAnnotationDrivenConfiguration.java

@@ -16,7 +16,6 @@
 
 package org.springframework.boot.autoconfigure.kafka;
 
-import java.util.List;
 import java.util.Map;
 
 import org.apache.kafka.clients.CommonClientConfigs;
@@ -30,7 +29,6 @@ import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
 import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
-import org.springframework.boot.autoconfigure.kafka.KafkaConnectionDetails.Node;
 import org.springframework.boot.context.properties.source.InvalidConfigurationPropertyValueException;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -87,17 +85,12 @@ class KafkaStreamsAnnotationDrivenConfiguration {
 
 	private void applyKafkaConnectionDetailsForStreams(Map<String, Object> properties,
 			KafkaConnectionDetails connectionDetails) {
-		properties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG,
+		properties.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, connectionDetails.getStreamsBootstrapServers());
-				nodesToStringList(connectionDetails.getStreamsBootstrapNodes()));
 		if (!(connectionDetails instanceof PropertiesKafkaConnectionDetails)) {
 			properties.put(CommonClientConfigs.SECURITY_PROTOCOL_CONFIG, "PLAINTEXT");
 		}
 	}
 
-	private List<String> nodesToStringList(List<Node> nodes) {
-		return nodes.stream().map((node) -> node.host() + ":" + node.port()).toList();
-	}
-
 	// Separate class required to avoid BeanCurrentlyInCreationException
 	static class KafkaStreamsFactoryBeanConfigurer implements InitializingBean {
 

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/kafka/PropertiesKafkaConnectionDetails.java

@@ -27,8 +27,6 @@ import java.util.List;
  */
 class PropertiesKafkaConnectionDetails implements KafkaConnectionDetails {
 
-	private final int DEFAULT_PORT = 9092;
-
 	private final KafkaProperties properties;
 
 	PropertiesKafkaConnectionDetails(KafkaProperties properties) {
@@ -36,40 +34,27 @@ class PropertiesKafkaConnectionDetails implements KafkaConnectionDetails {
 	}
 
 	@Override
-	public List<Node> getBootstrapNodes() {
+	public List<String> getBootstrapServers() {
-		return asNodes(this.properties.getBootstrapServers());
+		return this.properties.getBootstrapServers();
 	}
 
 	@Override
-	public List<Node> getConsumerBootstrapNodes() {
+	public List<String> getConsumerBootstrapServers() {
-		return bootstrapNodes(this.properties.getConsumer().getBootstrapServers());
+		return getServers(this.properties.getConsumer().getBootstrapServers());
 	}
 
 	@Override
-	public List<Node> getProducerBootstrapNodes() {
+	public List<String> getProducerBootstrapServers() {
-		return bootstrapNodes(this.properties.getProducer().getBootstrapServers());
+		return getServers(this.properties.getProducer().getBootstrapServers());
 	}
 
 	@Override
-	public List<Node> getStreamsBootstrapNodes() {
+	public List<String> getStreamsBootstrapServers() {
-		return bootstrapNodes(this.properties.getStreams().getBootstrapServers());
+		return getServers(this.properties.getStreams().getBootstrapServers());
-	}
-
-	private List<Node> bootstrapNodes(List<String> bootstrapServers) {
-		return (bootstrapServers != null) ? asNodes(bootstrapServers) : getBootstrapNodes();
 	}
 
-	private List<Node> asNodes(List<String> bootstrapServers) {
+	private List<String> getServers(List<String> servers) {
-		return bootstrapServers.stream().map(this::asNode).toList();
+		return (servers != null) ? servers : getBootstrapServers();
-	}
-
-	private Node asNode(String bootstrapNode) {
-		int separatorIndex = bootstrapNode.indexOf(':');
-		if (separatorIndex == -1) {
-			return new Node(bootstrapNode, this.DEFAULT_PORT);
-		}
-		return new Node(bootstrapNode.substring(0, separatorIndex),
-				Integer.parseInt(bootstrapNode.substring(separatorIndex + 1)));
 	}
 
 }

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/kafka/KafkaAutoConfigurationTests.java

@@ -839,8 +839,8 @@ class KafkaAutoConfigurationTests {
 		return new KafkaConnectionDetails() {
 
 			@Override
-			public List<Node> getBootstrapNodes() {
+			public List<String> getBootstrapServers() {
-				return List.of(new Node("kafka.example.com", 12345));
+				return List.of("kafka.example.com:12345");
 			}
 
 		};

spring-boot-project/spring-boot-testcontainers/src/main/java/org/springframework/boot/testcontainers/service/connection/kafka/KafkaContainerConnectionDetailsFactory.java

@@ -16,7 +16,6 @@
 
 package org.springframework.boot.testcontainers.service.connection.kafka;
 
-import java.net.URI;
 import java.util.List;
 
 import org.testcontainers.containers.KafkaContainer;
@@ -53,9 +52,8 @@ class KafkaContainerConnectionDetailsFactory
 		}
 
 		@Override
-		public List<Node> getBootstrapNodes() {
+		public List<String> getBootstrapServers() {
-			URI uri = URI.create(getContainer().getBootstrapServers());
+			return List.of(getContainer().getBootstrapServers());
-			return List.of(new Node(uri.getHost(), uri.getPort()));
 		}
 
 	}

spring-boot-project/spring-boot-testcontainers/src/main/java/org/springframework/boot/testcontainers/service/connection/redpanda/RedpandaContainerConnectionDetailsFactory.java

@@ -16,7 +16,6 @@
 
 package org.springframework.boot.testcontainers.service.connection.redpanda;
 
-import java.net.URI;
 import java.util.List;
 
 import org.testcontainers.redpanda.RedpandaContainer;
@@ -52,9 +51,8 @@ class RedpandaContainerConnectionDetailsFactory
 		}
 
 		@Override
-		public List<Node> getBootstrapNodes() {
+		public List<String> getBootstrapServers() {
-			URI uri = URI.create(getContainer().getBootstrapServers());
+			return List.of(getContainer().getBootstrapServers());
-			return List.of(new Node(uri.getHost(), uri.getPort()));
 		}
 
 	}