2 * Copyright (c) 2016 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.mdsal.singleton.dom.impl;
10 import static com.google.common.base.Preconditions.checkArgument;
11 import static com.google.common.base.Verify.verify;
12 import static com.google.common.base.Verify.verifyNotNull;
13 import static java.util.Objects.requireNonNull;
15 import com.google.common.annotations.VisibleForTesting;
16 import com.google.common.base.Strings;
17 import com.google.common.util.concurrent.Futures;
18 import com.google.common.util.concurrent.ListenableFuture;
19 import com.google.common.util.concurrent.MoreExecutors;
20 import java.util.ArrayList;
21 import java.util.List;
22 import java.util.concurrent.ConcurrentHashMap;
23 import java.util.concurrent.ConcurrentMap;
24 import java.util.concurrent.ExecutionException;
25 import javax.annotation.PreDestroy;
26 import javax.inject.Inject;
27 import javax.inject.Singleton;
28 import org.eclipse.jdt.annotation.NonNull;
29 import org.opendaylight.mdsal.eos.common.api.CandidateAlreadyRegisteredException;
30 import org.opendaylight.mdsal.eos.common.api.EntityOwnershipStateChange;
31 import org.opendaylight.mdsal.eos.dom.api.DOMEntity;
32 import org.opendaylight.mdsal.eos.dom.api.DOMEntityOwnershipListener;
33 import org.opendaylight.mdsal.eos.dom.api.DOMEntityOwnershipService;
34 import org.opendaylight.mdsal.singleton.common.api.ClusterSingletonService;
35 import org.opendaylight.mdsal.singleton.common.api.ClusterSingletonServiceProvider;
36 import org.opendaylight.mdsal.singleton.common.api.ClusterSingletonServiceRegistration;
37 import org.opendaylight.yangtools.concepts.Registration;
38 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
39 import org.osgi.service.component.annotations.Activate;
40 import org.osgi.service.component.annotations.Component;
41 import org.osgi.service.component.annotations.Deactivate;
42 import org.osgi.service.component.annotations.Reference;
43 import org.slf4j.Logger;
44 import org.slf4j.LoggerFactory;
47 * Implementation of {@link ClusterSingletonServiceProvider} working on top a {@link DOMEntityOwnershipService}.
50 @Component(service = ClusterSingletonServiceProvider.class)
51 public final class EOSClusterSingletonServiceProvider
52 implements ClusterSingletonServiceProvider, DOMEntityOwnershipListener, AutoCloseable {
53 private static final Logger LOG = LoggerFactory.getLogger(EOSClusterSingletonServiceProvider.class);
56 static final @NonNull String SERVICE_ENTITY_TYPE = "org.opendaylight.mdsal.ServiceEntityType";
58 static final @NonNull String CLOSE_SERVICE_ENTITY_TYPE = "org.opendaylight.mdsal.AsyncServiceCloseEntityType";
60 private final ConcurrentMap<String, ClusterSingletonServiceGroup> serviceGroupMap = new ConcurrentHashMap<>();
61 private final DOMEntityOwnershipService entityOwnershipService;
63 /* EOS Entity Listeners Registration */
64 private Registration serviceEntityListenerReg;
65 private Registration asyncCloseEntityListenerReg;
69 public EOSClusterSingletonServiceProvider(@Reference final DOMEntityOwnershipService entityOwnershipService) {
70 this.entityOwnershipService = requireNonNull(entityOwnershipService);
71 serviceEntityListenerReg = entityOwnershipService.registerListener(SERVICE_ENTITY_TYPE, this);
72 asyncCloseEntityListenerReg = entityOwnershipService.registerListener(CLOSE_SERVICE_ENTITY_TYPE, this);
73 LOG.info("Cluster Singleton Service started");
79 public synchronized void close() throws ExecutionException, InterruptedException {
80 if (serviceEntityListenerReg == null) {
85 LOG.info("Cluster Singleton Service stopping");
86 serviceEntityListenerReg.close();
87 serviceEntityListenerReg = null;
89 final var future = Futures.allAsList(serviceGroupMap.values().stream()
90 .map(ClusterSingletonServiceGroup::closeClusterSingletonGroup)
93 LOG.debug("Waiting for service groups to stop");
96 asyncCloseEntityListenerReg.close();
97 asyncCloseEntityListenerReg = null;
98 serviceGroupMap.clear();
101 LOG.info("Cluster Singleton Service stopped");
105 public synchronized ClusterSingletonServiceRegistration registerClusterSingletonService(
106 final ClusterSingletonService service) {
107 LOG.debug("Call registrationService {} method for ClusterSingletonService Provider {}", service, this);
109 final String serviceIdentifier = service.getIdentifier().getName();
110 checkArgument(!Strings.isNullOrEmpty(serviceIdentifier),
111 "ClusterSingletonService identifier may not be null nor empty");
113 final ClusterSingletonServiceGroup serviceGroup;
114 final var existing = serviceGroupMap.get(serviceIdentifier);
115 if (existing == null) {
116 serviceGroup = createGroup(serviceIdentifier, new ArrayList<>(1));
117 serviceGroupMap.put(serviceIdentifier, serviceGroup);
120 initializeOrRemoveGroup(serviceGroup);
121 } catch (CandidateAlreadyRegisteredException e) {
122 throw new IllegalArgumentException("Service group already registered", e);
125 serviceGroup = existing;
128 final var reg = new AbstractClusterSingletonServiceRegistration(service) {
130 protected void removeRegistration() {
131 // We need to bounce the unregistration through a ordered lock in order not to deal with asynchronous
132 // shutdown of the group and user registering it again.
133 EOSClusterSingletonServiceProvider.this.removeRegistration(serviceIdentifier, this);
137 serviceGroup.registerService(reg);
141 private ClusterSingletonServiceGroup createGroup(final String serviceIdentifier,
142 final List<ClusterSingletonServiceRegistration> services) {
143 return new ClusterSingletonServiceGroupImpl(serviceIdentifier, entityOwnershipService,
144 createEntity(SERVICE_ENTITY_TYPE, serviceIdentifier),
145 createEntity(CLOSE_SERVICE_ENTITY_TYPE, serviceIdentifier), services);
148 private void initializeOrRemoveGroup(final ClusterSingletonServiceGroup group)
149 throws CandidateAlreadyRegisteredException {
152 } catch (CandidateAlreadyRegisteredException e) {
153 serviceGroupMap.remove(group.getIdentifier(), group);
158 private void removeRegistration(final String serviceIdentifier, final ClusterSingletonServiceRegistration reg) {
159 final PlaceholderGroup placeHolder;
160 final ListenableFuture<?> future;
161 synchronized (this) {
162 final var lookup = verifyNotNull(serviceGroupMap.get(serviceIdentifier));
163 future = lookup.unregisterService(reg);
164 if (future == null) {
168 // Close the group and replace it with a placeholder
169 LOG.debug("Closing service group {}", serviceIdentifier);
170 placeHolder = new PlaceholderGroup(lookup, future);
172 final String identifier = reg.getInstance().getIdentifier().getName();
173 verify(serviceGroupMap.replace(identifier, lookup, placeHolder));
174 LOG.debug("Replaced group {} with {}", serviceIdentifier, placeHolder);
176 lookup.closeClusterSingletonGroup();
179 future.addListener(() -> finishShutdown(placeHolder), MoreExecutors.directExecutor());
182 private synchronized void finishShutdown(final PlaceholderGroup placeHolder) {
183 final var identifier = placeHolder.getIdentifier();
184 LOG.debug("Service group {} closed", identifier);
186 final var services = placeHolder.getServices();
187 if (services.isEmpty()) {
188 // No services, we are all done
189 if (serviceGroupMap.remove(identifier, placeHolder)) {
190 LOG.debug("Service group {} removed", placeHolder);
192 LOG.debug("Service group {} superseded by {}", placeHolder, serviceGroupMap.get(identifier));
197 // Placeholder is being retired, we are reusing its services as the seed for the group.
198 final var group = createGroup(identifier, services);
199 verify(serviceGroupMap.replace(identifier, placeHolder, group));
200 placeHolder.setSuccessor(group);
201 LOG.debug("Service group upgraded from {} to {}", placeHolder, group);
204 initializeOrRemoveGroup(group);
205 } catch (CandidateAlreadyRegisteredException e) {
206 LOG.error("Failed to register delayed group {}, it will remain inoperational", identifier, e);
211 public void ownershipChanged(final DOMEntity entity, final EntityOwnershipStateChange change,
212 final boolean inJeopardy) {
213 LOG.debug("Ownership change for ClusterSingletonService Provider on {} {} inJeopardy={}", entity, change,
216 final var serviceIdentifier = getServiceIdentifierFromEntity(entity);
217 final var serviceHolder = serviceGroupMap.get(serviceIdentifier);
218 if (serviceHolder != null) {
219 serviceHolder.ownershipChanged(entity, change, inJeopardy);
221 LOG.debug("ClusterSingletonServiceGroup was not found for serviceIdentifier {}", serviceIdentifier);
226 static String getServiceIdentifierFromEntity(final DOMEntity entity) {
227 final var yii = entity.getIdentifier();
228 final var niiwp = (NodeIdentifierWithPredicates) yii.getLastPathArgument();
229 return niiwp.values().iterator().next().toString();
233 * Creates an extended {@link DOMEntity} instance.
235 * @param entityType the type of the entity
236 * @param entityIdentifier the identifier of the entity
237 * @return instance of Entity extended GenericEntity type
240 static DOMEntity createEntity(final String entityType, final String entityIdentifier) {
241 return new DOMEntity(entityType, entityIdentifier);