capistrant commented on code in PR #18599: URL: https://github.com/apache/druid/pull/18599#discussion_r2594171255
########## extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/KubernetesResourceEventNotifier.java: ########## @@ -0,0 +1,118 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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 + * + * http://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.apache.druid.k8s.overlord.common; + +import io.fabric8.kubernetes.api.model.Pod; +import io.fabric8.kubernetes.api.model.batch.v1.Job; +import org.apache.druid.java.util.emitter.EmittingLogger; + +import java.util.List; +import java.util.concurrent.CompletableFuture; +import java.util.concurrent.ConcurrentHashMap; +import java.util.concurrent.CopyOnWriteArrayList; + +/** + * Manages event notifications for Kubernetes resources (Jobs and Pods). + * <p> + * Allows tasks to wait for specific resource changes without polling, improving efficiency and responsiveness. + * Crtical component of {@link CachingKubernetesPeonClient} functionality. + * </p> + */ +public class KubernetesResourceEventNotifier +{ + private static final EmittingLogger log = new EmittingLogger(KubernetesResourceEventNotifier.class); + + private final ConcurrentHashMap<String, List<CompletableFuture<Job>>> jobWatchers = new ConcurrentHashMap<>(); + private final ConcurrentHashMap<String, List<CompletableFuture<Pod>>> podWatchers = new ConcurrentHashMap<>(); + + /** + * Register to be notified when a job with the given name changes. + * The returned future will complete when the job is added, updated, or deleted. + * + * @param jobName The name of the job to watch + * @return A future that completes when the job changes + */ + public CompletableFuture<Job> waitForJobChange(String jobName) + { + CompletableFuture<Job> future = new CompletableFuture<>(); + jobWatchers.computeIfAbsent(jobName, k -> new CopyOnWriteArrayList<>()).add(future); + log.debug("Registered watcher for job [%s]. Total watchers: %d", jobName, jobWatchers.get(jobName).size()); + return future; + } + + /** + * Register to be notified when a pod for the given job name changes. + * The returned future will complete when a pod with the job-name label changes. + * + * @param jobName The job-name label value to watch for + * @return A future that completes when a matching pod changes + */ + public CompletableFuture<Pod> waitForPodChange(String jobName) + { + CompletableFuture<Pod> future = new CompletableFuture<>(); + podWatchers.computeIfAbsent(jobName, k -> new CopyOnWriteArrayList<>()).add(future); + log.debug("Registered watcher for pod with job-name [%s]. Total watchers: %d", jobName, podWatchers.get(jobName).size()); + return future; + } + + /** + * Notify all watchers that a job with the given name has changed. + * Completes all pending futures for this job and clears the watcher list. + * + * @param jobName The name of the job that changed + */ + public void notifyJobChange(String jobName, Job job) + { + List<CompletableFuture<Job>> futures = jobWatchers.get(jobName); + if (futures != null && !futures.isEmpty()) { + log.debug("Notifying %d watchers of job [%s] change", futures.size(), jobName); + futures.forEach(f -> f.complete(job)); + futures.clear(); + } + } + + /** + * Notify all watchers that a pod for the given job name has changed. + * Completes all pending futures for pods with this job-name label and clears the watcher list. + * + * @param jobName The job-name label value that changed + */ + public void notifyPodChange(String jobName, Pod pod) + { + List<CompletableFuture<Pod>> futures = podWatchers.get(jobName); + if (futures != null && !futures.isEmpty()) { + log.debug("Notifying %d watchers of pod change for job-name [%s]", futures.size(), jobName); + futures.forEach(f -> f.complete(pod)); + futures.clear(); + } Review Comment: I think the changes to stop storing as a list should make this more safe. Let me know if I missed anything. Thanks for noticing this! -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
