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