opendaylight/netconf/sal-netconf-connector/src/main/java/org/opendaylight/netconf/sal/connect/netconf/listener/NetconfDeviceCommunicator.java

   1 /*
   2  * Copyright (c) 2014 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.sal.connect.netconf.listener;
   9
  10 import com.google.common.base.Optional;
  11 import com.google.common.base.Strings;
  12 import com.google.common.collect.Lists;
  13 import com.google.common.util.concurrent.Futures;
  14 import com.google.common.util.concurrent.ListenableFuture;
  15 import com.google.common.util.concurrent.SettableFuture;
  16 import io.netty.util.concurrent.Future;
  17 import io.netty.util.concurrent.FutureListener;
  18 import io.netty.util.concurrent.GenericFutureListener;
  19 import java.util.ArrayDeque;
  20 import java.util.Iterator;
  21 import java.util.List;
  22 import java.util.Queue;
  23 import java.util.concurrent.atomic.AtomicBoolean;
  24 import java.util.concurrent.locks.Lock;
  25 import java.util.concurrent.locks.ReentrantLock;
  26 import org.opendaylight.controller.config.util.xml.XmlElement;
  27 import org.opendaylight.controller.config.util.xml.XmlUtil;
  28 import org.opendaylight.netconf.api.NetconfDocumentedException;
  29 import org.opendaylight.netconf.api.NetconfMessage;
  30 import org.opendaylight.netconf.api.NetconfTerminationReason;
  31 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  32 import org.opendaylight.netconf.client.NetconfClientDispatcher;
  33 import org.opendaylight.netconf.client.NetconfClientSession;
  34 import org.opendaylight.netconf.client.NetconfClientSessionListener;
  35 import org.opendaylight.netconf.client.conf.NetconfClientConfiguration;
  36 import org.opendaylight.netconf.client.conf.NetconfReconnectingClientConfiguration;
  37 import org.opendaylight.netconf.sal.connect.api.RemoteDevice;
  38 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceCommunicator;
  39 import org.opendaylight.netconf.sal.connect.netconf.util.NetconfMessageTransformUtil;
  40 import org.opendaylight.netconf.sal.connect.util.RemoteDeviceId;
  41 import org.opendaylight.yangtools.yang.common.QName;
  42 import org.opendaylight.yangtools.yang.common.RpcError;
  43 import org.opendaylight.yangtools.yang.common.RpcResult;
  44 import org.opendaylight.yangtools.yang.common.RpcResultBuilder;
  45 import org.slf4j.Logger;
  46 import org.slf4j.LoggerFactory;
  47
  48 public class NetconfDeviceCommunicator implements NetconfClientSessionListener, RemoteDeviceCommunicator<NetconfMessage> {
  49
  50     private static final Logger LOG = LoggerFactory.getLogger(NetconfDeviceCommunicator.class);
  51
  52     protected final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice;
  53     private final Optional<UserPreferences> overrideNetconfCapabilities;
  54     protected final RemoteDeviceId id;
  55     private final Lock sessionLock = new ReentrantLock();
  56
  57     // TODO implement concurrent message limit
  58     private final Queue<Request> requests = new ArrayDeque<>();
  59     private NetconfClientSession session;
  60
  61     private Future<?> initFuture;
  62     private SettableFuture<NetconfDeviceCapabilities> firstConnectionFuture;
  63
  64     // isSessionClosing indicates a close operation on the session is issued and
  65     // tearDown will surely be called later to finish the close.
  66     // Used to allow only one thread to enter tearDown and other threads should
  67     // NOT enter it simultaneously and should end its close operation without
  68     // calling tearDown to release the locks they hold to avoid deadlock.
  69     private volatile AtomicBoolean isSessionClosing = new AtomicBoolean(false);
  70
  71     public Boolean isSessionClosing() {
  72         return isSessionClosing.get();
  73     }
  74
  75     public NetconfDeviceCommunicator(final RemoteDeviceId id, final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  76             final UserPreferences NetconfSessionPreferences) {
  77         this(id, remoteDevice, Optional.of(NetconfSessionPreferences));
  78     }
  79
  80     public NetconfDeviceCommunicator(final RemoteDeviceId id,
  81                                      final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice) {
  82         this(id, remoteDevice, Optional.<UserPreferences>absent());
  83     }
  84
  85     private NetconfDeviceCommunicator(final RemoteDeviceId id, final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  86             final Optional<UserPreferences> overrideNetconfCapabilities) {
  87         this.id = id;
  88         this.remoteDevice = remoteDevice;
  89         this.overrideNetconfCapabilities = overrideNetconfCapabilities;
  90         this.firstConnectionFuture = SettableFuture.create();
  91     }
  92
  93     @Override
  94     public void onSessionUp(final NetconfClientSession session) {
  95         sessionLock.lock();
  96         try {
  97             LOG.debug("{}: Session established", id);
  98             this.session = session;
  99
 100             NetconfSessionPreferences netconfSessionPreferences =
 101                                              NetconfSessionPreferences.fromNetconfSession(session);
 102             LOG.trace("{}: Session advertised capabilities: {}", id,
 103                     netconfSessionPreferences);
 104
 105             if(overrideNetconfCapabilities.isPresent()) {
 106                 netconfSessionPreferences = overrideNetconfCapabilities.get().isOverride() ?
 107                         netconfSessionPreferences.replaceModuleCaps(overrideNetconfCapabilities.get().getSessionPreferences()) :
 108                         netconfSessionPreferences.addModuleCaps(overrideNetconfCapabilities.get().getSessionPreferences());
 109                 LOG.debug(
 110                         "{}: Session capabilities overridden, capabilities that will be used: {}",
 111                         id, netconfSessionPreferences);
 112             }
 113
 114
 115             remoteDevice.onRemoteSessionUp(netconfSessionPreferences, this);
 116             if (!firstConnectionFuture.isDone()) {
 117                 firstConnectionFuture.set(netconfSessionPreferences.getNetconfDeviceCapabilities());
 118             }
 119         }
 120         finally {
 121             sessionLock.unlock();
 122         }
 123     }
 124
 125     /**
 126      *
 127      * @param dispatcher
 128      * @param config
 129      * @return future that returns succes on first succesfull connection and failure when the underlying
 130      * reconnecting strategy runs out of reconnection attempts
 131      */
 132     public ListenableFuture<NetconfDeviceCapabilities> initializeRemoteConnection(final NetconfClientDispatcher dispatcher, final NetconfClientConfiguration config) {
 133         // TODO 2313 extract listener from configuration
 134         if(config instanceof NetconfReconnectingClientConfiguration) {
 135             initFuture = dispatcher.createReconnectingClient((NetconfReconnectingClientConfiguration) config);
 136         } else {
 137             initFuture = dispatcher.createClient(config);
 138         }
 139
 140
 141         initFuture.addListener(new GenericFutureListener<Future<Object>>(){
 142
 143             @Override
 144             public void operationComplete(Future<Object> future) throws Exception {
 145                 if (!future.isSuccess() && !future.isCancelled()) {
 146                     LOG.debug("{}: Connection failed", id, future.cause());
 147                     NetconfDeviceCommunicator.this.remoteDevice.onRemoteSessionFailed(future.cause());
 148                     if (firstConnectionFuture.isDone()) {
 149                         firstConnectionFuture.setException(future.cause());
 150                     }
 151                 }
 152             }
 153         });
 154         return firstConnectionFuture;
 155     }
 156
 157     public void disconnect() {
 158         // If session is already in closing, no need to close it again
 159         if(session != null && isSessionClosing.compareAndSet(false, true)) {
 160             session.close();
 161         }
 162     }
 163
 164     private void tearDown( String reason ) {
 165         if (!isSessionClosing()) {
 166             LOG.warn("It's curious that no one to close the session but tearDown is called!");
 167         }
 168         LOG.debug("Tearing down {}", reason);
 169         List<UncancellableFuture<RpcResult<NetconfMessage>>> futuresToCancel = Lists.newArrayList();
 170         sessionLock.lock();
 171         try {
 172             if( session != null ) {
 173                 session = null;
 174
 175                 /*
 176                  * Walk all requests, check if they have been executing
 177                  * or cancelled and remove them from the queue.
 178                  */
 179                 final Iterator<Request> it = requests.iterator();
 180                 while (it.hasNext()) {
 181                     final Request r = it.next();
 182                     if (r.future.isUncancellable()) {
 183                         futuresToCancel.add( r.future );
 184                         it.remove();
 185                     } else if (r.future.isCancelled()) {
 186                         // This just does some house-cleaning
 187                         it.remove();
 188                     }
 189                 }
 190
 191                 remoteDevice.onRemoteSessionDown();
 192             }
 193         }
 194         finally {
 195             sessionLock.unlock();
 196         }
 197
 198         // Notify pending request futures outside of the sessionLock to avoid unnecessarily
 199         // blocking the caller.
 200         for( UncancellableFuture<RpcResult<NetconfMessage>> future: futuresToCancel ) {
 201             if( Strings.isNullOrEmpty( reason ) ) {
 202                 future.set( createSessionDownRpcResult() );
 203             } else {
 204                 future.set( createErrorRpcResult( RpcError.ErrorType.TRANSPORT, reason ) );
 205             }
 206         }
 207
 208         isSessionClosing.set(false);
 209     }
 210
 211     private RpcResult<NetconfMessage> createSessionDownRpcResult() {
 212         return createErrorRpcResult( RpcError.ErrorType.TRANSPORT,
 213                              String.format( "The netconf session to %1$s is disconnected", id.getName() ) );
 214     }
 215
 216     private RpcResult<NetconfMessage> createErrorRpcResult( RpcError.ErrorType errorType, String message ) {
 217         return RpcResultBuilder.<NetconfMessage>failed()
 218                 .withError(errorType, NetconfDocumentedException.ErrorTag.operation_failed.getTagValue(), message).build();
 219     }
 220
 221     @Override
 222     public void onSessionDown(final NetconfClientSession session, final Exception e) {
 223         // If session is already in closing, no need to call tearDown again.
 224         if (isSessionClosing.compareAndSet(false, true)) {
 225             LOG.warn("{}: Session went down", id, e);
 226             tearDown( null );
 227         }
 228     }
 229
 230     @Override
 231     public void onSessionTerminated(final NetconfClientSession session, final NetconfTerminationReason reason) {
 232         // onSessionTerminated is called directly by disconnect, no need to compare and set isSessionClosing.
 233         LOG.warn("{}: Session terminated {}", id, reason);
 234         tearDown( reason.getErrorMessage() );
 235     }
 236
 237     @Override
 238     public void close() {
 239         // Cancel reconnect if in progress
 240         if(initFuture != null) {
 241             initFuture.cancel(false);
 242         }
 243         // Disconnect from device
 244         // tear down not necessary, called indirectly by the close in disconnect()
 245         disconnect();
 246     }
 247
 248     @Override
 249     public void onMessage(final NetconfClientSession session, final NetconfMessage message) {
 250         /*
 251          * Dispatch between notifications and messages. Messages need to be processed
 252          * with lock held, notifications do not.
 253          */
 254         if (isNotification(message)) {
 255             processNotification(message);
 256         } else {
 257             processMessage(message);
 258         }
 259     }
 260
 261     private void processMessage(final NetconfMessage message) {
 262         Request request = null;
 263         sessionLock.lock();
 264
 265         try {
 266             request = requests.peek();
 267             if (request != null && request.future.isUncancellable()) {
 268                 requests.poll();
 269             } else {
 270                 request = null;
 271                 LOG.warn("{}: Ignoring unsolicited message {}", id,
 272                         msgToS(message));
 273             }
 274         }
 275         finally {
 276             sessionLock.unlock();
 277         }
 278
 279         if( request != null ) {
 280
 281             LOG.debug("{}: Message received {}", id, message);
 282
 283             if(LOG.isTraceEnabled()) {
 284                 LOG.trace( "{}: Matched request: {} to response: {}", id, msgToS( request.request ), msgToS( message ) );
 285             }
 286
 287             try {
 288                 NetconfMessageTransformUtil.checkValidReply( request.request, message );
 289             } catch (final NetconfDocumentedException e) {
 290                 LOG.warn(
 291                         "{}: Invalid request-reply match, reply message contains different message-id, request: {}, response: {}",
 292                         id, msgToS(request.request), msgToS(message), e);
 293
 294                 request.future.set( RpcResultBuilder.<NetconfMessage>failed()
 295                         .withRpcError( NetconfMessageTransformUtil.toRpcError( e ) ).build() );
 296
 297                 //recursively processing message to eventually find matching request
 298                 processMessage(message);
 299
 300                 return;
 301             }
 302
 303             try {
 304                 NetconfMessageTransformUtil.checkSuccessReply(message);
 305             } catch(final NetconfDocumentedException e) {
 306                 LOG.warn(
 307                         "{}: Error reply from remote device, request: {}, response: {}",
 308                         id, msgToS(request.request), msgToS(message), e);
 309
 310                 request.future.set( RpcResultBuilder.<NetconfMessage>failed()
 311                         .withRpcError( NetconfMessageTransformUtil.toRpcError( e ) ).build() );
 312                 return;
 313             }
 314
 315             request.future.set( RpcResultBuilder.success( message ).build() );
 316         }
 317     }
 318
 319     private static String msgToS(final NetconfMessage msg) {
 320         return XmlUtil.toString(msg.getDocument());
 321     }
 322
 323     @Override
 324     public ListenableFuture<RpcResult<NetconfMessage>> sendRequest(final NetconfMessage message, final QName rpc) {
 325         sessionLock.lock();
 326         try {
 327             return sendRequestWithLock( message, rpc );
 328         } finally {
 329             sessionLock.unlock();
 330         }
 331     }
 332
 333     private ListenableFuture<RpcResult<NetconfMessage>> sendRequestWithLock(
 334                                                final NetconfMessage message, final QName rpc) {
 335         if(LOG.isTraceEnabled()) {
 336             LOG.trace("{}: Sending message {}", id, msgToS(message));
 337         }
 338
 339         if (session == null) {
 340             LOG.warn("{}: Session is disconnected, failing RPC request {}",
 341                     id, message);
 342             return Futures.immediateFuture( createSessionDownRpcResult() );
 343         }
 344
 345         final Request req = new Request( new UncancellableFuture<RpcResult<NetconfMessage>>(true),
 346                                          message );
 347         requests.add(req);
 348
 349         session.sendMessage(req.request).addListener(new FutureListener<Void>() {
 350             @Override
 351             public void operationComplete(final Future<Void> future) throws Exception {
 352                 if( !future.isSuccess() ) {
 353                     // We expect that a session down will occur at this point
 354                     LOG.debug("{}: Failed to send request {}", id,
 355                             XmlUtil.toString(req.request.getDocument()),
 356                             future.cause());
 357
 358                     if( future.cause() != null ) {
 359                         req.future.set( createErrorRpcResult( RpcError.ErrorType.TRANSPORT,
 360                                                               future.cause().getLocalizedMessage() ) );
 361                     } else {
 362                         req.future.set( createSessionDownRpcResult() ); // assume session is down
 363                     }
 364                     req.future.setException( future.cause() );
 365                 }
 366                 else {
 367                     LOG.trace("Finished sending request {}", req.request);
 368                 }
 369             }
 370         });
 371
 372         return req.future;
 373     }
 374
 375     private void processNotification(final NetconfMessage notification) {
 376         if(LOG.isTraceEnabled()) {
 377             LOG.trace("{}: Notification received: {}", id, notification);
 378         }
 379
 380         remoteDevice.onNotification(notification);
 381     }
 382
 383     private static boolean isNotification(final NetconfMessage message) {
 384         final XmlElement xmle = XmlElement.fromDomDocument(message.getDocument());
 385         return XmlNetconfConstants.NOTIFICATION_ELEMENT_NAME.equals(xmle.getName()) ;
 386     }
 387
 388     private static final class Request {
 389         final UncancellableFuture<RpcResult<NetconfMessage>> future;
 390         final NetconfMessage request;
 391
 392         private Request(final UncancellableFuture<RpcResult<NetconfMessage>> future,
 393                         final NetconfMessage request) {
 394             this.future = future;
 395             this.request = request;
 396         }
 397     }
 398 }