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