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.Semaphore;
  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     private final Semaphore semaphore;
  58     private final int concurentRpcMsgs;
  59
  60     private final Queue<Request> requests = new ArrayDeque<>();
  61     private NetconfClientSession session;
  62
  63     private Future<?> initFuture;
  64     private SettableFuture<NetconfDeviceCapabilities> firstConnectionFuture;
  65
  66     public NetconfDeviceCommunicator(final RemoteDeviceId id, final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  67             final UserPreferences NetconfSessionPreferences, final int rpcMessageLimit) {
  68         this(id, remoteDevice, Optional.of(NetconfSessionPreferences), rpcMessageLimit);
  69     }
  70
  71     public NetconfDeviceCommunicator(final RemoteDeviceId id,
  72                                      final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  73                                      final int rpcMessageLimit) {
  74         this(id, remoteDevice, Optional.<UserPreferences>absent(), rpcMessageLimit);
  75     }
  76
  77     private NetconfDeviceCommunicator(final RemoteDeviceId id, final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  78                                       final Optional<UserPreferences> overrideNetconfCapabilities, final int rpcMessageLimit) {
  79         this.concurentRpcMsgs = rpcMessageLimit;
  80         this.id = id;
  81         this.remoteDevice = remoteDevice;
  82         this.overrideNetconfCapabilities = overrideNetconfCapabilities;
  83         this.firstConnectionFuture = SettableFuture.create();
  84         this.semaphore = rpcMessageLimit > 0 ? new Semaphore(rpcMessageLimit) : null;
  85     }
  86
  87     @Override
  88     public void onSessionUp(final NetconfClientSession session) {
  89         sessionLock.lock();
  90         try {
  91             LOG.debug("{}: Session established", id);
  92             this.session = session;
  93
  94             NetconfSessionPreferences netconfSessionPreferences =
  95                                              NetconfSessionPreferences.fromNetconfSession(session);
  96             LOG.trace("{}: Session advertised capabilities: {}", id,
  97                     netconfSessionPreferences);
  98
  99             if(overrideNetconfCapabilities.isPresent()) {
 100                 netconfSessionPreferences = overrideNetconfCapabilities.get().isOverride() ?
 101                         netconfSessionPreferences.replaceModuleCaps(overrideNetconfCapabilities.get().getSessionPreferences()) :
 102                         netconfSessionPreferences.addModuleCaps(overrideNetconfCapabilities.get().getSessionPreferences());
 103                 LOG.debug(
 104                         "{}: Session capabilities overridden, capabilities that will be used: {}",
 105                         id, netconfSessionPreferences);
 106             }
 107
 108
 109             remoteDevice.onRemoteSessionUp(netconfSessionPreferences, this);
 110             if (!firstConnectionFuture.isDone()) {
 111                 firstConnectionFuture.set(netconfSessionPreferences.getNetconfDeviceCapabilities());
 112             }
 113         }
 114         finally {
 115             sessionLock.unlock();
 116         }
 117     }
 118
 119     /**
 120      *
 121      * @param dispatcher
 122      * @param config
 123      * @return future that returns succes on first succesfull connection and failure when the underlying
 124      * reconnecting strategy runs out of reconnection attempts
 125      */
 126     public ListenableFuture<NetconfDeviceCapabilities> initializeRemoteConnection(final NetconfClientDispatcher dispatcher, final NetconfClientConfiguration config) {
 127         if(config instanceof NetconfReconnectingClientConfiguration) {
 128             initFuture = dispatcher.createReconnectingClient((NetconfReconnectingClientConfiguration) config);
 129         } else {
 130             initFuture = dispatcher.createClient(config);
 131         }
 132
 133
 134         initFuture.addListener(new GenericFutureListener<Future<Object>>(){
 135
 136             @Override
 137             public void operationComplete(Future<Object> future) throws Exception {
 138                 if (!future.isSuccess() && !future.isCancelled()) {
 139                     LOG.debug("{}: Connection failed", id, future.cause());
 140                     NetconfDeviceCommunicator.this.remoteDevice.onRemoteSessionFailed(future.cause());
 141                     if (firstConnectionFuture.isDone()) {
 142                         firstConnectionFuture.setException(future.cause());
 143                     }
 144                 }
 145             }
 146         });
 147         return firstConnectionFuture;
 148     }
 149
 150     public void disconnect() {
 151         if(session != null) {
 152             session.close();
 153         }
 154     }
 155
 156     private void tearDown( String reason ) {
 157         LOG.debug("Tearing down {}", reason);
 158         List<UncancellableFuture<RpcResult<NetconfMessage>>> futuresToCancel = Lists.newArrayList();
 159         sessionLock.lock();
 160         try {
 161             if( session != null ) {
 162                 session = null;
 163
 164                 /*
 165                  * Walk all requests, check if they have been executing
 166                  * or cancelled and remove them from the queue.
 167                  */
 168                 final Iterator<Request> it = requests.iterator();
 169                 while (it.hasNext()) {
 170                     final Request r = it.next();
 171                     if (r.future.isUncancellable()) {
 172                         futuresToCancel.add( r.future );
 173                         it.remove();
 174                     } else if (r.future.isCancelled()) {
 175                         // This just does some house-cleaning
 176                         it.remove();
 177                     }
 178                 }
 179
 180                 remoteDevice.onRemoteSessionDown();
 181             }
 182         }
 183         finally {
 184             sessionLock.unlock();
 185         }
 186
 187         // Notify pending request futures outside of the sessionLock to avoid unnecessarily
 188         // blocking the caller.
 189         for( UncancellableFuture<RpcResult<NetconfMessage>> future: futuresToCancel ) {
 190             if( Strings.isNullOrEmpty( reason ) ) {
 191                 future.set( createSessionDownRpcResult() );
 192             } else {
 193                 future.set( createErrorRpcResult( RpcError.ErrorType.TRANSPORT, reason ) );
 194             }
 195         }
 196     }
 197
 198     private RpcResult<NetconfMessage> createSessionDownRpcResult() {
 199         return createErrorRpcResult( RpcError.ErrorType.TRANSPORT,
 200                              String.format( "The netconf session to %1$s is disconnected", id.getName() ) );
 201     }
 202
 203     private RpcResult<NetconfMessage> createErrorRpcResult( RpcError.ErrorType errorType, String message ) {
 204         return RpcResultBuilder.<NetconfMessage>failed()
 205                 .withError(errorType, NetconfDocumentedException.ErrorTag.operation_failed.getTagValue(), message).build();
 206     }
 207
 208     @Override
 209     public void onSessionDown(final NetconfClientSession session, final Exception e) {
 210         LOG.warn("{}: Session went down", id, e);
 211         tearDown( null );
 212     }
 213
 214     @Override
 215     public void onSessionTerminated(final NetconfClientSession session, final NetconfTerminationReason reason) {
 216         LOG.warn("{}: Session terminated {}", id, reason);
 217         tearDown( reason.getErrorMessage() );
 218     }
 219
 220     @Override
 221     public void close() {
 222         // Cancel reconnect if in progress
 223         if(initFuture != null) {
 224             initFuture.cancel(false);
 225         }
 226         // Disconnect from device
 227         if(session != null) {
 228             session.close();
 229             // tear down not necessary, called indirectly by above close
 230         }
 231     }
 232
 233     @Override
 234     public void onMessage(final NetconfClientSession session, final NetconfMessage message) {
 235         /*
 236          * Dispatch between notifications and messages. Messages need to be processed
 237          * with lock held, notifications do not.
 238          */
 239         if (isNotification(message)) {
 240             processNotification(message);
 241         } else {
 242             processMessage(message);
 243         }
 244     }
 245
 246     private void processMessage(final NetconfMessage message) {
 247         Request request = null;
 248         sessionLock.lock();
 249
 250         try {
 251             request = requests.peek();
 252             if (request != null && request.future.isUncancellable()) {
 253                 requests.poll();
 254                 // we have just removed one request from the queue
 255                 // we can also release one permit
 256                 if(semaphore != null) {
 257                     semaphore.release();
 258                 }
 259             } else {
 260                 request = null;
 261                 LOG.warn("{}: Ignoring unsolicited message {}", id,
 262                         msgToS(message));
 263             }
 264         }
 265         finally {
 266             sessionLock.unlock();
 267         }
 268
 269         if( request != null ) {
 270
 271             LOG.debug("{}: Message received {}", id, message);
 272
 273             if(LOG.isTraceEnabled()) {
 274                 LOG.trace( "{}: Matched request: {} to response: {}", id, msgToS( request.request ), msgToS( message ) );
 275             }
 276
 277             try {
 278                 NetconfMessageTransformUtil.checkValidReply( request.request, message );
 279             } catch (final NetconfDocumentedException e) {
 280                 LOG.warn(
 281                         "{}: Invalid request-reply match, reply message contains different message-id, request: {}, response: {}",
 282                         id, msgToS(request.request), msgToS(message), e);
 283
 284                 request.future.set( RpcResultBuilder.<NetconfMessage>failed()
 285                         .withRpcError( NetconfMessageTransformUtil.toRpcError( e ) ).build() );
 286
 287                 //recursively processing message to eventually find matching request
 288                 processMessage(message);
 289
 290                 return;
 291             }
 292
 293             try {
 294                 NetconfMessageTransformUtil.checkSuccessReply(message);
 295             } catch(final NetconfDocumentedException e) {
 296                 LOG.warn(
 297                         "{}: Error reply from remote device, request: {}, response: {}",
 298                         id, msgToS(request.request), msgToS(message), e);
 299
 300                 request.future.set( RpcResultBuilder.<NetconfMessage>failed()
 301                         .withRpcError( NetconfMessageTransformUtil.toRpcError( e ) ).build() );
 302                 return;
 303             }
 304
 305             request.future.set( RpcResultBuilder.success( message ).build() );
 306         }
 307     }
 308
 309     private static String msgToS(final NetconfMessage msg) {
 310         return XmlUtil.toString(msg.getDocument());
 311     }
 312
 313     @Override
 314     public ListenableFuture<RpcResult<NetconfMessage>> sendRequest(final NetconfMessage message, final QName rpc) {
 315         sessionLock.lock();
 316
 317         if (semaphore != null && !semaphore.tryAcquire()) {
 318             LOG.warn("Limit of concurrent rpc messages was reached (limit :" +
 319                     concurentRpcMsgs + "). Rpc reply message is needed. Discarding request of Netconf device with id" + id.getName());
 320             sessionLock.unlock();
 321             return Futures.immediateFailedFuture(new NetconfDocumentedException("Limit of rpc messages was reached (Limit :" +
 322                     concurentRpcMsgs + ") waiting for emptying the queue of Netconf device with id" + id.getName()));
 323         }
 324
 325         try {
 326             return sendRequestWithLock(message, rpc);
 327         } finally {
 328             sessionLock.unlock();
 329         }
 330     }
 331
 332     private ListenableFuture<RpcResult<NetconfMessage>> sendRequestWithLock(
 333                                                final NetconfMessage message, final QName rpc) {
 334         if(LOG.isTraceEnabled()) {
 335             LOG.trace("{}: Sending message {}", id, msgToS(message));
 336         }
 337
 338         if (session == null) {
 339             LOG.warn("{}: Session is disconnected, failing RPC request {}",
 340                     id, message);
 341             return Futures.immediateFuture( createSessionDownRpcResult() );
 342         }
 343
 344         final Request req = new Request( new UncancellableFuture<RpcResult<NetconfMessage>>(true),
 345                                          message );
 346         requests.add(req);
 347
 348         session.sendMessage(req.request).addListener(new FutureListener<Void>() {
 349             @Override
 350             public void operationComplete(final Future<Void> future) throws Exception {
 351                 if( !future.isSuccess() ) {
 352                     // We expect that a session down will occur at this point
 353                     LOG.debug("{}: Failed to send request {}", id,
 354                             XmlUtil.toString(req.request.getDocument()),
 355                             future.cause());
 356
 357                     if( future.cause() != null ) {
 358                         req.future.set( createErrorRpcResult( RpcError.ErrorType.TRANSPORT,
 359                                                               future.cause().getLocalizedMessage() ) );
 360                     } else {
 361                         req.future.set( createSessionDownRpcResult() ); // assume session is down
 362                     }
 363                     req.future.setException( future.cause() );
 364                 }
 365                 else {
 366                     LOG.trace("Finished sending request {}", req.request);
 367                 }
 368             }
 369         });
 370
 371         return req.future;
 372     }
 373
 374     private void processNotification(final NetconfMessage notification) {
 375         if(LOG.isTraceEnabled()) {
 376             LOG.trace("{}: Notification received: {}", id, notification);
 377         }
 378
 379         remoteDevice.onNotification(notification);
 380     }
 381
 382     private static boolean isNotification(final NetconfMessage message) {
 383         final XmlElement xmle = XmlElement.fromDomDocument(message.getDocument());
 384         return XmlNetconfConstants.NOTIFICATION_ELEMENT_NAME.equals(xmle.getName()) ;
 385     }
 386
 387     private static final class Request {
 388         final UncancellableFuture<RpcResult<NetconfMessage>> future;
 389         final NetconfMessage request;
 390
 391         private Request(final UncancellableFuture<RpcResult<NetconfMessage>> future,
 392                         final NetconfMessage request) {
 393             this.future = future;
 394             this.request = request;
 395         }
 396     }
 397 }