Java tutorial
/** * 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.ambari.server.checks; import com.google.inject.Singleton; import org.apache.ambari.server.AmbariException; import org.apache.ambari.server.controller.PrereqCheckRequest; import org.apache.ambari.server.orm.entities.RepositoryVersionEntity; import org.apache.ambari.server.state.Cluster; import org.apache.ambari.server.state.Service; import org.apache.ambari.server.state.ServiceComponent; import org.apache.ambari.server.state.ServiceComponentHost; import org.apache.ambari.server.state.stack.PrereqCheckStatus; import org.apache.ambari.server.state.stack.PrerequisiteCheck; import org.apache.commons.lang.StringUtils; import java.util.ArrayList; import java.util.Collection; import java.util.HashSet; import java.util.List; import java.util.Map; /** * Warns about host components whose upgrade state is VERSION_MISMATCH. Never triggers * fail. */ @Singleton @UpgradeCheck(group = UpgradeCheckGroup.COMPONENT_VERSION, order = 7.0f, required = true) public class ServiceComponentHostVersionMatchCheck extends AbstractCheckDescriptor { public ServiceComponentHostVersionMatchCheck() { super(CheckDescription.VERSION_MISMATCH); } @Override public void perform(PrerequisiteCheck prerequisiteCheck, PrereqCheckRequest request) throws AmbariException { final String clusterName = request.getClusterName(); final Cluster cluster = clustersProvider.get().getCluster(clusterName); RepositoryVersionEntity clusterVersion = cluster.getCurrentClusterVersion().getRepositoryVersion(); List<String> errorMessages = new ArrayList<String>(); Map<String, Service> services = cluster.getServices(); // If CURRENT cluster version is already computed if (clusterVersion != null) { String desiredVersion = clusterVersion.getVersion(); for (Service service : services.values()) { validateService(service, desiredVersion, prerequisiteCheck, errorMessages); } } else { listAllComponentsWithHostVersions(services.values(), prerequisiteCheck, errorMessages); } if (!prerequisiteCheck.getFailedOn().isEmpty()) { prerequisiteCheck.setStatus(PrereqCheckStatus.WARNING); String failReason = getFailReason(prerequisiteCheck, request); prerequisiteCheck.setFailReason(String.format(failReason, StringUtils.join(errorMessages, "\n"))); } } /** * Iterates over all service components belonging to a service and validates them. * @param service * @param desiredVersion current version for cluster. All service component versions * should match it * @param prerequisiteCheck * @param errorMessages */ private void validateService(Service service, String desiredVersion, PrerequisiteCheck prerequisiteCheck, List<String> errorMessages) { Map<String, ServiceComponent> serviceComponents = service.getServiceComponents(); for (ServiceComponent serviceComponent : serviceComponents.values()) { validateServiceComponent(serviceComponent, desiredVersion, prerequisiteCheck, errorMessages); } } /** * Iterates over all host components belonging to a service component and validates them. * @param serviceComponent * @param desiredVersion current version for cluster. All host component versions * should match it * @param prerequisiteCheck * @param errorMessages */ private void validateServiceComponent(ServiceComponent serviceComponent, String desiredVersion, PrerequisiteCheck prerequisiteCheck, List<String> errorMessages) { if (!serviceComponent.isVersionAdvertised()) return; Map<String, ServiceComponentHost> serviceComponentHosts = serviceComponent.getServiceComponentHosts(); for (ServiceComponentHost serviceComponentHost : serviceComponentHosts.values()) { validateServiceComponentHost(serviceComponentHost, desiredVersion, prerequisiteCheck, errorMessages); } } /** * Validates host component. If upgrade state of host component is VERSION_MISMATCH, * adds hostname to a Failed On map of prerequisite check, and adds all other * host component version details to errorMessages * @param serviceComponentHost * @param desiredVersion current version for cluster. Component host version * should match it * @param prerequisiteCheck * @param errorMessages */ private void validateServiceComponentHost(ServiceComponentHost serviceComponentHost, String desiredVersion, PrerequisiteCheck prerequisiteCheck, List<String> errorMessages) { String actualVersion = serviceComponentHost.getVersion(); if (StringUtils.equals(desiredVersion, actualVersion)) return; String hostName = serviceComponentHost.getHostName(); String serviceComponentName = serviceComponentHost.getServiceComponentName(); String message = hostName + "/" + serviceComponentName + " desired version: " + desiredVersion + ", actual version: " + actualVersion; prerequisiteCheck.getFailedOn().add(hostName); errorMessages.add(message); } /** * Validates component version in a cluster that has no CURRENT version defined. * If there is more than one actual host component version in cluster, collects * details for warning. * @param services * @param prerequisiteCheck * @param errorMessages */ private void listAllComponentsWithHostVersions(Collection<Service> services, PrerequisiteCheck prerequisiteCheck, List<String> errorMessages) { if (countDistinctVersionsOnHosts(services) <= 1) return; for (Service service : services) { for (ServiceComponent serviceComponent : service.getServiceComponents().values()) { if (!serviceComponent.isVersionAdvertised()) continue; ArrayList<Object> hostVersions = new ArrayList<>(); for (ServiceComponentHost serviceComponentHost : serviceComponent.getServiceComponentHosts() .values()) { hostVersions.add(serviceComponentHost.getVersion()); prerequisiteCheck.getFailedOn().add(serviceComponentHost.getHostName()); } String message = serviceComponent.getName() + " host versions: " + hostVersions; errorMessages.add(message); } } } /** * Iterates over services, and enumerates reported versions of host components. * @param services collection of services * @return number of distinct actual versions found */ private int countDistinctVersionsOnHosts(Collection<Service> services) { HashSet<Object> versions = new HashSet<>(); for (Service service : services) { for (ServiceComponent serviceComponent : service.getServiceComponents().values()) { if (!serviceComponent.isVersionAdvertised()) continue; for (ServiceComponentHost serviceComponentHost : serviceComponent.getServiceComponentHosts() .values()) { versions.add(serviceComponentHost.getVersion()); } } } return versions.size(); } }