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                 .withKey(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 () -> {
 142             synchronized (NetconfNotificationManager.this) {
 143                 streamListeners.remove(listener);
 144             }
 145         };
 146     }
 147
 148     @Override
 149     public synchronized void close() {
 150         // Unregister all listeners
 151         for (final GenericNotificationListenerReg genericNotificationListenerReg : notificationListeners.values()) {
 152             genericNotificationListenerReg.close();
 153         }
 154         notificationListeners.clear();
 155
 156         // Unregister all publishers
 157         for (final GenericNotificationPublisherReg notificationPublisher : notificationPublishers) {
 158             notificationPublisher.close();
 159         }
 160         notificationPublishers.clear();
 161
 162         // Clear stream Listeners
 163         streamListeners.clear();
 164     }
 165
 166     @Override
 167     public synchronized NotificationPublisherRegistration registerNotificationPublisher(final Stream stream) {
 168         Preconditions.checkNotNull(stream);
 169         final StreamNameType streamName = stream.getName();
 170
 171         LOG.debug("Notification publisher registered for stream: {}", streamName);
 172         if (LOG.isTraceEnabled()) {
 173             LOG.trace("Notification publisher registered for stream: {}", stream);
 174         }
 175
 176         if (streamMetadata.containsKey(streamName)) {
 177             LOG.warn("Notification stream {} already registered as: {}. Will be reused", streamName,
 178                     streamMetadata.get(streamName));
 179         } else {
 180             streamMetadata.put(streamName, stream);
 181         }
 182
 183         availableStreams.add(streamName);
 184
 185         final GenericNotificationPublisherReg genericNotificationPublisherReg =
 186                 new GenericNotificationPublisherReg(this, streamName) {
 187             @Override
 188             public void close() {
 189                 synchronized (NetconfNotificationManager.this) {
 190                     super.close();
 191                 }
 192             }
 193         };
 194
 195         notificationPublishers.add(genericNotificationPublisherReg);
 196
 197         notifyStreamAdded(stream);
 198         return genericNotificationPublisherReg;
 199     }
 200
 201     private void unregisterNotificationPublisher(
 202             final StreamNameType streamName,
 203             final GenericNotificationPublisherReg genericNotificationPublisherReg) {
 204         availableStreams.remove(streamName);
 205         notificationPublishers.remove(genericNotificationPublisherReg);
 206
 207         LOG.debug("Notification publisher unregistered for stream: {}", streamName);
 208
 209         // Notify stream listeners if all publishers are gone and also clear metadata for stream
 210         if (!isStreamAvailable(streamName)) {
 211             LOG.debug("Notification stream: {} became unavailable", streamName);
 212             streamMetadata.remove(streamName);
 213             notifyStreamRemoved(streamName);
 214         }
 215     }
 216
 217     private synchronized void notifyStreamAdded(final Stream stream) {
 218         for (final NetconfNotificationStreamListener streamListener : streamListeners) {
 219             streamListener.onStreamRegistered(stream);
 220         }
 221     }
 222
 223     private synchronized void notifyStreamRemoved(final StreamNameType stream) {
 224         for (final NetconfNotificationStreamListener streamListener : streamListeners) {
 225             streamListener.onStreamUnregistered(stream);
 226         }
 227     }
 228
 229     @Override
 230     public BaseNotificationPublisherRegistration registerBaseNotificationPublisher() {
 231         final NotificationPublisherRegistration notificationPublisherRegistration =
 232                 registerNotificationPublisher(BASE_NETCONF_STREAM);
 233         return new BaseNotificationPublisherReg(notificationPublisherRegistration);
 234     }
 235
 236     private static class GenericNotificationPublisherReg implements NotificationPublisherRegistration {
 237         private NetconfNotificationManager baseListener;
 238         private final StreamNameType registeredStream;
 239
 240         GenericNotificationPublisherReg(final NetconfNotificationManager baseListener,
 241                                         final StreamNameType registeredStream) {
 242             this.baseListener = baseListener;
 243             this.registeredStream = registeredStream;
 244         }
 245
 246         @Override
 247         public void close() {
 248             baseListener.unregisterNotificationPublisher(registeredStream, this);
 249             baseListener = null;
 250         }
 251
 252         @Override
 253         public void onNotification(final StreamNameType stream, final NetconfNotification notification) {
 254             Preconditions.checkState(baseListener != null, "Already closed");
 255             Preconditions.checkArgument(stream.equals(registeredStream));
 256             baseListener.onNotification(stream, notification);
 257         }
 258     }
 259
 260     private static class BaseNotificationPublisherReg implements BaseNotificationPublisherRegistration {
 261
 262         static final SchemaPath CAPABILITY_CHANGE_SCHEMA_PATH = SchemaPath.create(true, NetconfCapabilityChange.QNAME);
 263         static final SchemaPath SESSION_START_PATH = SchemaPath.create(true, NetconfSessionStart.QNAME);
 264         static final SchemaPath SESSION_END_PATH = SchemaPath.create(true, NetconfSessionEnd.QNAME);
 265
 266         private final NotificationPublisherRegistration baseRegistration;
 267
 268         BaseNotificationPublisherReg(final NotificationPublisherRegistration baseRegistration) {
 269             this.baseRegistration = baseRegistration;
 270         }
 271
 272         @Override
 273         public void close() {
 274             baseRegistration.close();
 275         }
 276
 277         private static NetconfNotification serializeNotification(final Notification notification,
 278                 final SchemaPath path) {
 279             return NotificationsTransformUtil.transform(notification, path);
 280         }
 281
 282         @Override
 283         public void onCapabilityChanged(final NetconfCapabilityChange capabilityChange) {
 284             baseRegistration.onNotification(BASE_STREAM_NAME,
 285                     serializeNotification(capabilityChange, CAPABILITY_CHANGE_SCHEMA_PATH));
 286         }
 287
 288         @Override
 289         public void onSessionStarted(final NetconfSessionStart start) {
 290             baseRegistration.onNotification(BASE_STREAM_NAME, serializeNotification(start, SESSION_START_PATH));
 291         }
 292
 293         @Override
 294         public void onSessionEnded(final NetconfSessionEnd end) {
 295             baseRegistration.onNotification(BASE_STREAM_NAME, serializeNotification(end, SESSION_END_PATH));
 296         }
 297     }
 298
 299     private class GenericNotificationListenerReg implements NotificationListenerRegistration {
 300         private final NetconfNotificationListener listener;
 301
 302         GenericNotificationListenerReg(final NetconfNotificationListener listener) {
 303             this.listener = listener;
 304         }
 305
 306         public NetconfNotificationListener getListener() {
 307             return listener;
 308         }
 309
 310         @Override
 311         public void close() {
 312             notificationListeners.remove(BASE_STREAM_NAME, this);
 313         }
 314     }
 315 }