/*
* Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/epl-v10.html
*/
package org.opendaylight.mdsal.dom.broker;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMultimap;
import com.google.common.collect.Multimap;
import com.google.common.collect.Multimaps;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.MoreExecutors;
import com.google.common.util.concurrent.ThreadFactoryBuilder;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import javax.annotation.PreDestroy;
import javax.inject.Inject;
import org.eclipse.jdt.annotation.NonNull;
import org.opendaylight.mdsal.dom.api.DOMNotification;
import org.opendaylight.mdsal.dom.api.DOMNotificationListener;
import org.opendaylight.mdsal.dom.api.DOMNotificationPublishService;
import org.opendaylight.mdsal.dom.api.DOMNotificationService;
import org.opendaylight.mdsal.dom.spi.DOMNotificationSubscriptionListener;
import org.opendaylight.mdsal.dom.spi.DOMNotificationSubscriptionListenerRegistry;
import org.opendaylight.yangtools.concepts.AbstractListenerRegistration;
import org.opendaylight.yangtools.concepts.AbstractRegistration;
import org.opendaylight.yangtools.concepts.ListenerRegistration;
import org.opendaylight.yangtools.concepts.Registration;
import org.opendaylight.yangtools.util.ListenerRegistry;
import org.opendaylight.yangtools.util.concurrent.EqualityQueuedNotificationManager;
import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager;
import org.opendaylight.yangtools.yang.common.Empty;
import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier.Absolute;
import org.osgi.service.component.annotations.Activate;
import org.osgi.service.component.annotations.Component;
import org.osgi.service.component.annotations.Deactivate;
import org.osgi.service.metatype.annotations.AttributeDefinition;
import org.osgi.service.metatype.annotations.Designate;
import org.osgi.service.metatype.annotations.ObjectClassDefinition;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Joint implementation of {@link DOMNotificationPublishService} and {@link DOMNotificationService}. Provides
* routing of notifications from publishers to subscribers.
*
*
* Internal implementation one by using a {@link QueuedNotificationManager}.
*
*/
@Component(immediate = true, configurationPid = "org.opendaylight.mdsal.dom.notification", service = {
DOMNotificationService.class, DOMNotificationPublishService.class,
DOMNotificationSubscriptionListenerRegistry.class
})
@Designate(ocd = DOMNotificationRouter.Config.class)
// Non-final for testing
public class DOMNotificationRouter implements AutoCloseable, DOMNotificationPublishService,
DOMNotificationService, DOMNotificationSubscriptionListenerRegistry {
@ObjectClassDefinition()
public @interface Config {
@AttributeDefinition(name = "notification-queue-depth")
int queueDepth() default 65536;
}
@VisibleForTesting
abstract static sealed class Reg extends AbstractListenerRegistration {
Reg(final @NonNull T listener) {
super(listener);
}
}
private final class SingleReg extends Reg {
SingleReg(final @NonNull T listener) {
super(listener);
}
@Override
protected void removeRegistration() {
DOMNotificationRouter.this.removeRegistration(this);
}
}
private static final class ComponentReg extends Reg {
ComponentReg(final @NonNull DOMNotificationListener listener) {
super(listener);
}
@Override
protected void removeRegistration() {
// No-op
}
}
private static final Logger LOG = LoggerFactory.getLogger(DOMNotificationRouter.class);
private static final @NonNull ListenableFuture> NO_LISTENERS = Futures.immediateFuture(Empty.value());
private final ListenerRegistry subscriptionListeners =
ListenerRegistry.create();
private final EqualityQueuedNotificationManager,
DOMNotificationRouterEvent> queueNotificationManager;
private final ScheduledThreadPoolExecutor observer;
private final ExecutorService executor;
private volatile Multimap> listeners = ImmutableMultimap.of();
@Inject
public DOMNotificationRouter(final int maxQueueCapacity) {
observer = new ScheduledThreadPoolExecutor(1, new ThreadFactoryBuilder()
.setDaemon(true)
.setNameFormat("DOMNotificationRouter-observer-%d")
.build());
executor = Executors.newCachedThreadPool(new ThreadFactoryBuilder()
.setDaemon(true)
.setNameFormat("DOMNotificationRouter-listeners-%d")
.build());
queueNotificationManager = new EqualityQueuedNotificationManager<>("DOMNotificationRouter", executor,
maxQueueCapacity, DOMNotificationRouter::deliverEvents);
LOG.info("DOM Notification Router started");
}
@Activate
public DOMNotificationRouter(final Config config) {
this(config.queueDepth());
}
@Override
public synchronized ListenerRegistration registerNotificationListener(
final T listener, final Collection types) {
final var reg = new SingleReg<>(listener);
if (!types.isEmpty()) {
final var b = ImmutableMultimap.>builder();
b.putAll(listeners);
for (var t : types) {
b.put(t, reg);
}
replaceListeners(b.build());
}
return reg;
}
@Override
public synchronized Registration registerNotificationListeners(
final Map typeToListener) {
final var b = ImmutableMultimap.>builder();
b.putAll(listeners);
final var tmp = new HashMap();
for (var e : typeToListener.entrySet()) {
b.put(e.getKey(), tmp.computeIfAbsent(e.getValue(), ComponentReg::new));
}
replaceListeners(b.build());
final var regs = List.copyOf(tmp.values());
return new AbstractRegistration() {
@Override
protected void removeRegistration() {
regs.forEach(ComponentReg::close);
removeRegistrations(regs);
}
};
}
private synchronized void removeRegistration(final SingleReg> reg) {
replaceListeners(ImmutableMultimap.copyOf(Multimaps.filterValues(listeners, input -> input != reg)));
}
private synchronized void removeRegistrations(final List regs) {
replaceListeners(ImmutableMultimap.copyOf(Multimaps.filterValues(listeners, input -> !regs.contains(input))));
}
/**
* Swaps registered listeners and triggers notification update.
*
* @param newListeners is used to notify listenerTypes changed
*/
private void replaceListeners(final Multimap> newListeners) {
listeners = newListeners;
notifyListenerTypesChanged(newListeners.keySet());
}
@SuppressWarnings("checkstyle:IllegalCatch")
private void notifyListenerTypesChanged(final Set typesAfter) {
final var listenersAfter = subscriptionListeners.streamListeners().collect(ImmutableList.toImmutableList());
executor.execute(() -> {
for (var subListener : listenersAfter) {
try {
subListener.onSubscriptionChanged(typesAfter);
} catch (final Exception e) {
LOG.warn("Uncaught exception during invoking listener {}", subListener, e);
}
}
});
}
@Override
public ListenerRegistration registerSubscriptionListener(
final L listener) {
final var initialTypes = listeners.keySet();
executor.execute(() -> listener.onSubscriptionChanged(initialTypes));
return subscriptionListeners.register(listener);
}
@VisibleForTesting
@NonNull ListenableFuture extends Object> publish(final DOMNotification notification,
final Collection> subscribers) {
final var futures = new ArrayList>(subscribers.size());
subscribers.forEach(subscriber -> {
final var event = new DOMNotificationRouterEvent(notification);
futures.add(event.future());
queueNotificationManager.submitNotification(subscriber, event);
});
return Futures.transform(Futures.successfulAsList(futures), ignored -> (Void)null,
MoreExecutors.directExecutor());
}
@Override
public ListenableFuture extends Object> putNotification(final DOMNotification notification)
throws InterruptedException {
final var subscribers = listeners.get(notification.getType());
return subscribers.isEmpty() ? NO_LISTENERS : publish(notification, subscribers);
}
@Override
public ListenableFuture extends Object> offerNotification(final DOMNotification notification) {
final var subscribers = listeners.get(notification.getType());
return subscribers.isEmpty() ? NO_LISTENERS : publish(notification, subscribers);
}
@Override
public ListenableFuture extends Object> offerNotification(final DOMNotification notification, final long timeout,
final TimeUnit unit) throws InterruptedException {
final var subscribers = listeners.get(notification.getType());
if (subscribers.isEmpty()) {
return NO_LISTENERS;
}
// Attempt to perform a non-blocking publish first
final var noBlock = publish(notification, subscribers);
if (!DOMNotificationPublishService.REJECTED.equals(noBlock)) {
return noBlock;
}
try {
final var publishThread = Thread.currentThread();
final var timerTask = observer.schedule(publishThread::interrupt, timeout, unit);
final var withBlock = putNotification(notification);
timerTask.cancel(true);
if (observer.getQueue().size() > 50) {
observer.purge();
}
return withBlock;
} catch (InterruptedException e) {
return DOMNotificationPublishService.REJECTED;
}
}
@PreDestroy
@Deactivate
@Override
public void close() {
observer.shutdown();
executor.shutdown();
LOG.info("DOM Notification Router stopped");
}
@VisibleForTesting
ExecutorService executor() {
return executor;
}
@VisibleForTesting
ExecutorService observer() {
return observer;
}
@VisibleForTesting
Multimap listeners() {
return listeners;
}
@VisibleForTesting
ListenerRegistry subscriptionListeners() {
return subscriptionListeners;
}
private static void deliverEvents(final AbstractListenerRegistration extends DOMNotificationListener> reg,
final ImmutableList events) {
if (reg.notClosed()) {
final var listener = reg.getInstance();
for (var event : events) {
event.deliverTo(listener);
}
} else {
events.forEach(DOMNotificationRouterEvent::clear);
}
}
}