netconf/mdsal-netconf-notification/src/main/java/org/opendaylight/netconf/mdsal/notification/impl/NetconfNotificationManager.java

   1 /*
   2  * Copyright (c) 2015 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   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
   7  */
   8 package org.opendaylight.netconf.mdsal.notification.impl;
   9
  10 import static com.google.common.base.Preconditions.checkArgument;
  11 import static com.google.common.base.Preconditions.checkState;
  12 import static java.util.Objects.requireNonNull;
  13
  14 import com.google.common.collect.HashMultimap;
  15 import com.google.common.collect.HashMultiset;
  16 import com.google.common.collect.Lists;
  17 import com.google.common.collect.Multimap;
  18 import com.google.common.collect.Multiset;
  19 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
  20 import java.util.HashMap;
  21 import java.util.HashSet;
  22 import java.util.Map;
  23 import java.util.Set;
  24 import org.checkerframework.checker.lock.qual.GuardedBy;
  25 import org.opendaylight.netconf.mdsal.notification.impl.ops.NotificationsTransformUtil;
  26 import org.opendaylight.netconf.notifications.BaseNotificationPublisherRegistration;
  27 import org.opendaylight.netconf.notifications.NetconfNotification;
  28 import org.opendaylight.netconf.notifications.NetconfNotificationCollector;
  29 import org.opendaylight.netconf.notifications.NetconfNotificationListener;
  30 import org.opendaylight.netconf.notifications.NetconfNotificationRegistry;
  31 import org.opendaylight.netconf.notifications.NotificationListenerRegistration;
  32 import org.opendaylight.netconf.notifications.NotificationPublisherRegistration;
  33 import org.opendaylight.netconf.notifications.NotificationRegistration;
  34 import org.opendaylight.netconf.notifications.YangLibraryPublisherRegistration;
  35 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.notification._1._0.rev080714.StreamNameType;
  36 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netmod.notification.rev080714.netconf.Streams;
  37 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netmod.notification.rev080714.netconf.StreamsBuilder;
  38 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netmod.notification.rev080714.netconf.streams.Stream;
  39 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netmod.notification.rev080714.netconf.streams.StreamBuilder;
  40 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netmod.notification.rev080714.netconf.streams.StreamKey;
  41 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfCapabilityChange;
  42 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfSessionEnd;
  43 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfSessionStart;
  44 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.yang.library.rev160621.YangLibraryChange;
  45 import org.opendaylight.yangtools.yang.binding.Notification;
  46 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  47 import org.slf4j.Logger;
  48 import org.slf4j.LoggerFactory;
  49
  50 /**
  51  *  A thread-safe implementation NetconfNotificationRegistry.
  52  */
  53 public class NetconfNotificationManager implements NetconfNotificationCollector, NetconfNotificationRegistry,
  54         NetconfNotificationListener, AutoCloseable {
  55
  56     public static final StreamNameType BASE_STREAM_NAME = new StreamNameType("NETCONF");
  57     public static final Stream BASE_NETCONF_STREAM;
  58
  59     static {
  60         BASE_NETCONF_STREAM = new StreamBuilder()
  61                 .setName(BASE_STREAM_NAME)
  62                 .withKey(new StreamKey(BASE_STREAM_NAME))
  63                 .setReplaySupport(false)
  64                 .setDescription("Default Event Stream")
  65                 .build();
  66     }
  67
  68     private static final Logger LOG = LoggerFactory.getLogger(NetconfNotificationManager.class);
  69
  70     // TODO excessive synchronization provides thread safety but is most likely not optimal
  71     // (combination of concurrent collections might improve performance)
  72     // And also calling callbacks from a synchronized block is dangerous
  73     // since the listeners/publishers can block the whole notification processing
  74
  75     @GuardedBy("this")
  76     private final Multimap<StreamNameType, GenericNotificationListenerReg> notificationListeners =
  77             HashMultimap.create();
  78
  79     @GuardedBy("this")
  80     private final Set<NetconfNotificationStreamListener> streamListeners = new HashSet<>();
  81
  82     @GuardedBy("this")
  83     private final Map<StreamNameType, Stream> streamMetadata = new HashMap<>();
  84
  85     @GuardedBy("this")
  86     private final Multiset<StreamNameType> availableStreams = HashMultiset.create();
  87
  88     @GuardedBy("this")
  89     private final Set<GenericNotificationPublisherReg> notificationPublishers = new HashSet<>();
  90
  91     @Override
  92     public synchronized void onNotification(final StreamNameType stream, final NetconfNotification notification) {
  93         LOG.debug("Notification of type {} detected", stream);
  94         if (LOG.isTraceEnabled()) {
  95             LOG.debug("Notification of type {} detected: {}", stream, notification);
  96         }
  97
  98         for (final GenericNotificationListenerReg listenerReg : notificationListeners.get(BASE_STREAM_NAME)) {
  99             listenerReg.getListener().onNotification(BASE_STREAM_NAME, notification);
 100         }
 101     }
 102
 103     @Override
 104     public synchronized NotificationListenerRegistration registerNotificationListener(
 105             final StreamNameType stream,
 106             final NetconfNotificationListener listener) {
 107         requireNonNull(stream);
 108         requireNonNull(listener);
 109
 110         LOG.trace("Notification listener registered for stream: {}", stream);
 111
 112         final GenericNotificationListenerReg genericNotificationListenerReg =
 113                 new GenericNotificationListenerReg(listener) {
 114             @Override
 115             public void close() {
 116                 synchronized (NetconfNotificationManager.this) {
 117                     LOG.trace("Notification listener unregistered for stream: {}", stream);
 118                     super.close();
 119                 }
 120             }
 121         };
 122
 123         notificationListeners.put(BASE_STREAM_NAME, genericNotificationListenerReg);
 124         return genericNotificationListenerReg;
 125     }
 126
 127     @Override
 128     public synchronized Streams getNotificationPublishers() {
 129         return new StreamsBuilder().setStream(Lists.newArrayList(streamMetadata.values())).build();
 130     }
 131
 132     @Override
 133     public synchronized boolean isStreamAvailable(final StreamNameType streamNameType) {
 134         return availableStreams.contains(streamNameType);
 135     }
 136
 137     @Override
 138     public synchronized NotificationRegistration registerStreamListener(
 139             final NetconfNotificationStreamListener listener) {
 140         streamListeners.add(listener);
 141
 142         // Notify about all already available
 143         for (final Stream availableStream : streamMetadata.values()) {
 144             listener.onStreamRegistered(availableStream);
 145         }
 146
 147         return () -> {
 148             synchronized (NetconfNotificationManager.this) {
 149                 streamListeners.remove(listener);
 150             }
 151         };
 152     }
 153
 154     @Override
 155     public synchronized void close() {
 156         // Unregister all listeners
 157         for (final GenericNotificationListenerReg genericNotificationListenerReg : notificationListeners.values()) {
 158             genericNotificationListenerReg.close();
 159         }
 160         notificationListeners.clear();
 161
 162         // Unregister all publishers
 163         for (final GenericNotificationPublisherReg notificationPublisher : notificationPublishers) {
 164             notificationPublisher.close();
 165         }
 166         notificationPublishers.clear();
 167
 168         // Clear stream Listeners
 169         streamListeners.clear();
 170     }
 171
 172     @Override
 173     public synchronized NotificationPublisherRegistration registerNotificationPublisher(final Stream stream) {
 174         final StreamNameType streamName = requireNonNull(stream).getName();
 175
 176         LOG.debug("Notification publisher registered for stream: {}", streamName);
 177         if (LOG.isTraceEnabled()) {
 178             LOG.trace("Notification publisher registered for stream: {}", stream);
 179         }
 180
 181         if (streamMetadata.containsKey(streamName)) {
 182             LOG.warn("Notification stream {} already registered as: {}. Will be reused", streamName,
 183                     streamMetadata.get(streamName));
 184         } else {
 185             streamMetadata.put(streamName, stream);
 186         }
 187
 188         availableStreams.add(streamName);
 189
 190         final GenericNotificationPublisherReg genericNotificationPublisherReg =
 191                 new GenericNotificationPublisherReg(this, streamName) {
 192             @Override
 193             public void close() {
 194                 synchronized (NetconfNotificationManager.this) {
 195                     super.close();
 196                 }
 197             }
 198         };
 199
 200         notificationPublishers.add(genericNotificationPublisherReg);
 201
 202         notifyStreamAdded(stream);
 203         return genericNotificationPublisherReg;
 204     }
 205
 206     @SuppressFBWarnings(value = "UPM_UNCALLED_PRIVATE_METHOD",
 207             justification = "https://github.com/spotbugs/spotbugs/issues/811")
 208     private void unregisterNotificationPublisher(
 209             final StreamNameType streamName,
 210             final GenericNotificationPublisherReg genericNotificationPublisherReg) {
 211         availableStreams.remove(streamName);
 212         notificationPublishers.remove(genericNotificationPublisherReg);
 213
 214         LOG.debug("Notification publisher unregistered for stream: {}", streamName);
 215
 216         // Notify stream listeners if all publishers are gone and also clear metadata for stream
 217         if (!isStreamAvailable(streamName)) {
 218             LOG.debug("Notification stream: {} became unavailable", streamName);
 219             streamMetadata.remove(streamName);
 220             notifyStreamRemoved(streamName);
 221         }
 222     }
 223
 224     private synchronized void notifyStreamAdded(final Stream stream) {
 225         for (final NetconfNotificationStreamListener streamListener : streamListeners) {
 226             streamListener.onStreamRegistered(stream);
 227         }
 228     }
 229
 230     private synchronized void notifyStreamRemoved(final StreamNameType stream) {
 231         for (final NetconfNotificationStreamListener streamListener : streamListeners) {
 232             streamListener.onStreamUnregistered(stream);
 233         }
 234     }
 235
 236     @Override
 237     public BaseNotificationPublisherRegistration registerBaseNotificationPublisher() {
 238         final NotificationPublisherRegistration notificationPublisherRegistration =
 239                 registerNotificationPublisher(BASE_NETCONF_STREAM);
 240         return new BaseNotificationPublisherReg(notificationPublisherRegistration);
 241     }
 242
 243     @Override
 244     public YangLibraryPublisherRegistration registerYangLibraryPublisher() {
 245         final NotificationPublisherRegistration notificationPublisherRegistration =
 246                 registerNotificationPublisher(BASE_NETCONF_STREAM);
 247         return new YangLibraryPublisherReg(notificationPublisherRegistration);
 248     }
 249
 250     private static class GenericNotificationPublisherReg implements NotificationPublisherRegistration {
 251         private NetconfNotificationManager baseListener;
 252         private final StreamNameType registeredStream;
 253
 254         GenericNotificationPublisherReg(final NetconfNotificationManager baseListener,
 255                                         final StreamNameType registeredStream) {
 256             this.baseListener = baseListener;
 257             this.registeredStream = registeredStream;
 258         }
 259
 260         @Override
 261         public void close() {
 262             baseListener.unregisterNotificationPublisher(registeredStream, this);
 263             baseListener = null;
 264         }
 265
 266         @Override
 267         public void onNotification(final StreamNameType stream, final NetconfNotification notification) {
 268             checkState(baseListener != null, "Already closed");
 269             checkArgument(stream.equals(registeredStream));
 270             baseListener.onNotification(stream, notification);
 271         }
 272     }
 273
 274     private static class BaseNotificationPublisherReg implements BaseNotificationPublisherRegistration {
 275
 276         static final SchemaPath CAPABILITY_CHANGE_SCHEMA_PATH = SchemaPath.create(true, NetconfCapabilityChange.QNAME);
 277         static final SchemaPath SESSION_START_PATH = SchemaPath.create(true, NetconfSessionStart.QNAME);
 278         static final SchemaPath SESSION_END_PATH = SchemaPath.create(true, NetconfSessionEnd.QNAME);
 279
 280         private final NotificationPublisherRegistration baseRegistration;
 281
 282         BaseNotificationPublisherReg(final NotificationPublisherRegistration baseRegistration) {
 283             this.baseRegistration = baseRegistration;
 284         }
 285
 286         @Override
 287         public void close() {
 288             baseRegistration.close();
 289         }
 290
 291         private static NetconfNotification serializeNotification(final Notification notification,
 292                 final SchemaPath path) {
 293             return NotificationsTransformUtil.transform(notification, path);
 294         }
 295
 296         @Override
 297         public void onCapabilityChanged(final NetconfCapabilityChange capabilityChange) {
 298             baseRegistration.onNotification(BASE_STREAM_NAME,
 299                     serializeNotification(capabilityChange, CAPABILITY_CHANGE_SCHEMA_PATH));
 300         }
 301
 302         @Override
 303         public void onSessionStarted(final NetconfSessionStart start) {
 304             baseRegistration.onNotification(BASE_STREAM_NAME, serializeNotification(start, SESSION_START_PATH));
 305         }
 306
 307         @Override
 308         public void onSessionEnded(final NetconfSessionEnd end) {
 309             baseRegistration.onNotification(BASE_STREAM_NAME, serializeNotification(end, SESSION_END_PATH));
 310         }
 311     }
 312
 313     private static class YangLibraryPublisherReg implements YangLibraryPublisherRegistration {
 314         static final SchemaPath YANG_LIBRARY_CHANGE_PATH = SchemaPath.create(true, YangLibraryChange.QNAME);
 315
 316         private final NotificationPublisherRegistration baseRegistration;
 317
 318         YangLibraryPublisherReg(final NotificationPublisherRegistration baseRegistration) {
 319             this.baseRegistration = baseRegistration;
 320         }
 321
 322         @Override
 323         public void onYangLibraryChange(YangLibraryChange yangLibraryChange) {
 324             baseRegistration.onNotification(BASE_STREAM_NAME, NotificationsTransformUtil
 325                     .transform(yangLibraryChange, YANG_LIBRARY_CHANGE_PATH));
 326         }
 327
 328         @Override
 329         public void close() {
 330             baseRegistration.close();
 331         }
 332     }
 333
 334     private class GenericNotificationListenerReg implements NotificationListenerRegistration {
 335         private final NetconfNotificationListener listener;
 336
 337         GenericNotificationListenerReg(final NetconfNotificationListener listener) {
 338             this.listener = listener;
 339         }
 340
 341         public NetconfNotificationListener getListener() {
 342             return listener;
 343         }
 344
 345         @Override
 346         public void close() {
 347             notificationListeners.remove(BASE_STREAM_NAME, this);
 348         }
 349     }
 350 }