Merge pull request #2053 from wind57/major-changes-in-fabric8-discovery-implementation

major refactor of fabric8 discovery implementation

Author: ryanjbaxter

docs/modules/ROOT/pages/discovery-client.adoc

@@ -236,7 +236,7 @@ milliseconds (by default it is `30000`). For the http discovery server this must
 ----
 
 The heartbeat event will contain the target references (and their namespaces of the addresses of all endpoints
-(for the exact details of what will get returned you can take a look inside `KubernetesCatalogWatch`). This is an implementation detail, and listeners of the heartbeat event
+(for the exact details of what will get returned you can take a look inside `Fabric8CatalogWatch`). This is an implementation detail, and listeners of the heartbeat event
 should not rely on the details. Instead, they should see if there are differences between two subsequent heartbeats via `equals` method. We will take care to return a correct implementation that adheres to the equals contract.
 The endpoints will be queried in either :
 - `all-namespaces` (enabled via `spring.cloud.kubernetes.discovery.all-namespaces=true`)

spring-cloud-kubernetes-commons/src/main/java/org/springframework/cloud/kubernetes/commons/discovery/KubernetesExternalNameServiceInstance.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2019-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.cloud.kubernetes.commons.discovery;
+
+import java.net.URI;
+import java.util.Map;
+
+import org.springframework.cloud.client.ServiceInstance;
+
+/**
+ * Type of {@link org.springframework.cloud.client.ServiceInstance} when
+ * "spec.type=ExternalName".
+ *
+ * @author wind57
+ */
+public record KubernetesExternalNameServiceInstance(String serviceId, String host, String instanceId,
+		Map<String, String> metadata) implements ServiceInstance {
+
+	@Override
+	public String getServiceId() {
+		return serviceId;
+	}
+
+	@Override
+	public String getHost() {
+		return host;
+	}
+
+	@Override
+	public int getPort() {
+		return -1;
+	}
+
+	@Override
+	public boolean isSecure() {
+		return false;
+	}
+
+	@Override
+	public URI getUri() {
+		return URI.create(host);
+	}
+
+	@Override
+	public Map<String, String> getMetadata() {
+		return metadata;
+	}
+
+	public String getInstanceId() {
+		return instanceId;
+	}
+
+	public String type() {
+		return "ExternalName";
+	}
+
+}

spring-cloud-kubernetes-fabric8-discovery/src/main/java/org/springframework/cloud/kubernetes/fabric8/discovery/KubernetesCatalogWatch.java renamed to spring-cloud-kubernetes-fabric8-discovery/src/main/java/org/springframework/cloud/kubernetes/fabric8/discovery/Fabric8CatalogWatch.java

@@ -31,7 +31,6 @@
 import org.springframework.cloud.kubernetes.commons.discovery.EndpointNameAndNamespace;
 import org.springframework.cloud.kubernetes.commons.discovery.KubernetesDiscoveryProperties;
 import org.springframework.context.ApplicationEventPublisher;
-import org.springframework.context.ApplicationEventPublisherAware;
 import org.springframework.core.log.LogAccessor;
 import org.springframework.scheduling.annotation.Scheduled;
 
@@ -43,32 +42,28 @@
 /**
  * @author Oleg Vyukov
  */
-public class KubernetesCatalogWatch implements ApplicationEventPublisherAware {
+final class Fabric8CatalogWatch {
 
 	private static final String DISCOVERY_GROUP_VERSION = DISCOVERY_GROUP + "/" + DISCOVERY_VERSION;
 
-	private static final LogAccessor LOG = new LogAccessor(LogFactory.getLog(KubernetesCatalogWatch.class));
+	private static final LogAccessor LOG = new LogAccessor(LogFactory.getLog(Fabric8CatalogWatch.class));
 
 	private final Fabric8CatalogWatchContext context;
 
 	private Function<Fabric8CatalogWatchContext, List<EndpointNameAndNamespace>> stateGenerator;
 
 	private volatile List<EndpointNameAndNamespace> catalogEndpointsState = null;
 
-	private ApplicationEventPublisher publisher;
+	private final ApplicationEventPublisher publisher;
 
-	public KubernetesCatalogWatch(KubernetesClient kubernetesClient, KubernetesDiscoveryProperties properties,
-			KubernetesNamespaceProvider namespaceProvider) {
+	Fabric8CatalogWatch(KubernetesClient kubernetesClient, KubernetesDiscoveryProperties properties,
+			KubernetesNamespaceProvider namespaceProvider, ApplicationEventPublisher publisher) {
 		context = new Fabric8CatalogWatchContext(kubernetesClient, properties, namespaceProvider);
-	}
-
-	@Override
-	public void setApplicationEventPublisher(ApplicationEventPublisher publisher) {
 		this.publisher = publisher;
 	}
 
 	@Scheduled(fixedDelayString = "${" + CATALOG_WATCH_PROPERTY_WITH_DEFAULT_VALUE + "}")
-	public void catalogServicesWatch() {
+	void catalogServicesWatch() {
 		try {
 
 			List<EndpointNameAndNamespace> currentState = stateGenerator.apply(context);
@@ -97,7 +92,7 @@ Function<Fabric8CatalogWatchContext, List<EndpointNameAndNamespace>> stateGenera
 		if (context.properties().useEndpointSlices()) {
 			// can't use try with resources here as it will close the client
 			KubernetesClient client = context.kubernetesClient();
-			// this emulates : 'kubectl api-resources | grep -i EndpointSlice'
+			// this emulates: 'kubectl api-resources | grep -i EndpointSlice'
 			boolean found = client.getApiGroups()
 				.getGroups()
 				.stream()

spring-cloud-kubernetes-fabric8-discovery/src/main/java/org/springframework/cloud/kubernetes/fabric8/discovery/KubernetesCatalogWatchAutoConfiguration.java renamed to spring-cloud-kubernetes-fabric8-discovery/src/main/java/org/springframework/cloud/kubernetes/fabric8/discovery/Fabric8CatalogWatchAutoConfiguration.java

@@ -25,6 +25,7 @@
 import org.springframework.cloud.kubernetes.commons.discovery.KubernetesDiscoveryProperties;
 import org.springframework.cloud.kubernetes.commons.discovery.KubernetesDiscoveryPropertiesAutoConfiguration;
 import org.springframework.cloud.kubernetes.fabric8.Fabric8AutoConfiguration;
+import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.env.Environment;
@@ -37,13 +38,13 @@
 @Configuration(proxyBeanMethods = false)
 @ConditionalOnKubernetesCatalogWatcherEnabled
 @AutoConfigureAfter({ Fabric8AutoConfiguration.class, KubernetesDiscoveryPropertiesAutoConfiguration.class })
-public class KubernetesCatalogWatchAutoConfiguration {
+final class Fabric8CatalogWatchAutoConfiguration {
 
 	@Bean
 	@ConditionalOnMissingBean
-	public KubernetesCatalogWatch kubernetesCatalogWatch(KubernetesClient client,
-			KubernetesDiscoveryProperties properties, Environment environment) {
-		return new KubernetesCatalogWatch(client, properties, new KubernetesNamespaceProvider(environment));
+	Fabric8CatalogWatch fabric8CatalogWatch(KubernetesClient client, KubernetesDiscoveryProperties properties,
+			Environment environment, ApplicationEventPublisher publisher) {
+		return new Fabric8CatalogWatch(client, properties, new KubernetesNamespaceProvider(environment), publisher);
 	}
 
 }

spring-cloud-kubernetes-fabric8-discovery/src/main/java/org/springframework/cloud/kubernetes/fabric8/discovery/Fabric8ConfigServerBootstrapper.java

@@ -20,6 +20,7 @@
 
 import io.fabric8.kubernetes.client.Config;
 import io.fabric8.kubernetes.client.KubernetesClient;
+import jakarta.annotation.Nonnull;
 
 import org.springframework.boot.bootstrap.BootstrapRegistry;
 import org.springframework.cloud.config.client.ConfigServerConfigDataLocationResolver.PropertyResolver;
@@ -37,7 +38,7 @@
 class Fabric8ConfigServerBootstrapper extends KubernetesConfigServerBootstrapper {
 
 	@Override
-	public void initialize(BootstrapRegistry registry) {
+	public void initialize(@Nonnull BootstrapRegistry registry) {
 		if (hasConfigServerInstanceProvider()) {
 			return;
 		}
@@ -61,8 +62,8 @@ public void initialize(BootstrapRegistry registry) {
 			if (!getDiscoveryEnabled(context)) {
 				return (id) -> Collections.emptyList();
 			}
-			if (context.isRegistered(KubernetesDiscoveryClient.class)) {
-				KubernetesDiscoveryClient client = context.get(KubernetesDiscoveryClient.class);
+			if (context.isRegistered(Fabric8DiscoveryClient.class)) {
+				Fabric8DiscoveryClient client = context.get(Fabric8DiscoveryClient.class);
 				return client::getInstances;
 			}
 			else {
@@ -72,12 +73,11 @@ public void initialize(BootstrapRegistry registry) {
 					.kubernetesClientConfig(context.get(KubernetesClientProperties.class));
 				KubernetesClient kubernetesClient = fabric8AutoConfiguration.kubernetesClient(config);
 				KubernetesDiscoveryProperties discoveryProperties = context.get(KubernetesDiscoveryProperties.class);
-				KubernetesDiscoveryClient discoveryClient = new KubernetesDiscoveryClient(kubernetesClient,
-						discoveryProperties,
-						KubernetesClientServicesFunctionProvider.servicesFunction(discoveryProperties,
-								new KubernetesNamespaceProvider(propertyResolver
-									.get(KubernetesNamespaceProvider.NAMESPACE_PROPERTY, String.class, null))),
-						null, new ServicePortSecureResolver(discoveryProperties));
+				Fabric8DiscoveryClient discoveryClient = new Fabric8DiscoveryClient(kubernetesClient,
+						discoveryProperties, new ServicePortSecureResolver(discoveryProperties),
+						new KubernetesNamespaceProvider(propertyResolver
+							.get(KubernetesNamespaceProvider.NAMESPACE_PROPERTY, String.class, null)),
+						new Fabric8DiscoveryClientSpelAutoConfiguration().predicate(discoveryProperties));
 				return discoveryClient::getInstances;
 			}
 		});

spring-cloud-kubernetes-fabric8-discovery/src/main/java/org/springframework/cloud/kubernetes/fabric8/discovery/KubernetesDiscoveryClient.java renamed to spring-cloud-kubernetes-fabric8-discovery/src/main/java/org/springframework/cloud/kubernetes/fabric8/discovery/Fabric8DiscoveryClient.java

@@ -36,21 +36,19 @@
 import org.springframework.cloud.kubernetes.commons.discovery.ServiceMetadata;
 import org.springframework.cloud.kubernetes.commons.discovery.ServicePortNameAndNumber;
 import org.springframework.cloud.kubernetes.commons.discovery.ServicePortSecureResolver;
-import org.springframework.context.EnvironmentAware;
-import org.springframework.core.env.Environment;
 import org.springframework.core.log.LogAccessor;
 
 import static org.springframework.cloud.kubernetes.commons.discovery.DiscoveryClientUtils.endpointsPort;
 import static org.springframework.cloud.kubernetes.commons.discovery.DiscoveryClientUtils.serviceInstance;
 import static org.springframework.cloud.kubernetes.commons.discovery.DiscoveryClientUtils.serviceInstanceMetadata;
 import static org.springframework.cloud.kubernetes.commons.discovery.KubernetesDiscoveryConstants.EXTERNAL_NAME;
 import static org.springframework.cloud.kubernetes.fabric8.Fabric8Utils.serviceMetadata;
+import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8DiscoveryClientUtils.addresses;
+import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8DiscoveryClientUtils.endpointSubsetsPortData;
+import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8DiscoveryClientUtils.endpoints;
+import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8DiscoveryClientUtils.services;
 import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8InstanceIdHostPodNameSupplier.externalName;
 import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8InstanceIdHostPodNameSupplier.nonExternalName;
-import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8KubernetesDiscoveryClientUtils.addresses;
-import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8KubernetesDiscoveryClientUtils.endpointSubsetsPortData;
-import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8KubernetesDiscoveryClientUtils.endpoints;
-import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8KubernetesDiscoveryClientUtils.services;
 import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8PodLabelsAndAnnotationsSupplier.externalName;
 import static org.springframework.cloud.kubernetes.fabric8.discovery.Fabric8PodLabelsAndAnnotationsSupplier.nonExternalName;
 
@@ -60,40 +58,29 @@
  * @author Ioannis Canellos
  * @author Tim Ysewyn
  */
-public class KubernetesDiscoveryClient implements DiscoveryClient, EnvironmentAware {
+final class Fabric8DiscoveryClient implements DiscoveryClient {
 
-	private static final LogAccessor LOG = new LogAccessor(LogFactory.getLog(KubernetesDiscoveryClient.class));
+	private static final LogAccessor LOG = new LogAccessor(LogFactory.getLog(Fabric8DiscoveryClient.class));
 
 	private final KubernetesDiscoveryProperties properties;
 
-	private final KubernetesClientServicesFunction kubernetesClientServicesFunction;
-
 	private final ServicePortSecureResolver servicePortSecureResolver;
 
-	private final Fabric8DiscoveryServicesAdapter adapter;
-
 	private final KubernetesClient client;
 
-	private KubernetesNamespaceProvider namespaceProvider;
+	private final KubernetesNamespaceProvider namespaceProvider;
 
-	public KubernetesDiscoveryClient(KubernetesClient client,
-			KubernetesDiscoveryProperties kubernetesDiscoveryProperties,
-			KubernetesClientServicesFunction kubernetesClientServicesFunction) {
+	private final Predicate<Service> predicate;
 
-		this(client, kubernetesDiscoveryProperties, kubernetesClientServicesFunction, null,
-				new ServicePortSecureResolver(kubernetesDiscoveryProperties));
-	}
-
-	KubernetesDiscoveryClient(KubernetesClient client, KubernetesDiscoveryProperties kubernetesDiscoveryProperties,
-			KubernetesClientServicesFunction kubernetesClientServicesFunction, Predicate<Service> filter,
-			ServicePortSecureResolver servicePortSecureResolver) {
+	Fabric8DiscoveryClient(KubernetesClient client, KubernetesDiscoveryProperties kubernetesDiscoveryProperties,
+			ServicePortSecureResolver servicePortSecureResolver, KubernetesNamespaceProvider namespaceProvider,
+			Predicate<Service> predicate) {
 
 		this.client = client;
 		this.properties = kubernetesDiscoveryProperties;
 		this.servicePortSecureResolver = servicePortSecureResolver;
-		this.kubernetesClientServicesFunction = kubernetesClientServicesFunction;
-		this.adapter = new Fabric8DiscoveryServicesAdapter(kubernetesClientServicesFunction,
-				kubernetesDiscoveryProperties, filter);
+		this.namespaceProvider = namespaceProvider;
+		this.predicate = predicate;
 	}
 
 	@Override
@@ -105,7 +92,8 @@ public String description() {
 	public List<ServiceInstance> getInstances(String serviceId) {
 		Objects.requireNonNull(serviceId);
 
-		List<Endpoints> allEndpoints = getEndPointsList(serviceId).stream().toList();
+		List<Endpoints> allEndpoints = endpoints(properties, client, namespaceProvider, "fabric8-discovery", serviceId,
+				predicate);
 
 		List<ServiceInstance> instances = new ArrayList<>();
 		for (Endpoints endpoints : allEndpoints) {
@@ -135,8 +123,20 @@ public List<ServiceInstance> getInstances(String serviceId) {
 		return instances;
 	}
 
-	public List<Endpoints> getEndPointsList(String serviceId) {
-		return endpoints(properties, client, namespaceProvider, "fabric8-discovery", serviceId, adapter.filter());
+	@Override
+	public List<String> getServices() {
+		List<String> services = services(properties, client, namespaceProvider, predicate, null, "fabric8 discovery")
+			.stream()
+			.map(service -> service.getMetadata().getName())
+			.distinct()
+			.toList();
+		LOG.debug(() -> "will return services : " + services);
+		return services;
+	}
+
+	@Override
+	public int getOrder() {
+		return properties.order();
 	}
 
 	private List<ServiceInstance> serviceInstances(Endpoints endpoints, String serviceId) {
@@ -176,31 +176,4 @@ private List<ServiceInstance> serviceInstances(Endpoints endpoints, String servi
 		return instances;
 	}
 
-	@Override
-	public List<String> getServices() {
-		List<String> services = adapter.apply(client).stream().map(s -> s.getMetadata().getName()).distinct().toList();
-		LOG.debug(() -> "will return services : " + services);
-		return services;
-	}
-
-	@Deprecated(forRemoval = true)
-	public List<String> getServices(Predicate<Service> filter) {
-		return new Fabric8DiscoveryServicesAdapter(kubernetesClientServicesFunction, properties, filter).apply(client)
-			.stream()
-			.map(s -> s.getMetadata().getName())
-			.distinct()
-			.toList();
-	}
-
-	@Override
-	public int getOrder() {
-		return properties.order();
-	}
-
-	@Deprecated(forRemoval = true)
-	@Override
-	public final void setEnvironment(Environment environment) {
-		namespaceProvider = new KubernetesNamespaceProvider(environment);
-	}
-
 }