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 java.util.ArrayDeque;
  18 import java.util.Iterator;
  19 import java.util.List;
  20 import java.util.Queue;
  21 import java.util.concurrent.Semaphore;
  22 import java.util.concurrent.atomic.AtomicBoolean;
  23 import java.util.concurrent.locks.Lock;
  24 import java.util.concurrent.locks.ReentrantLock;
  25
  26 import org.opendaylight.controller.config.util.xml.DocumentedException;
  27 import org.opendaylight.controller.config.util.xml.XmlElement;
  28 import org.opendaylight.controller.config.util.xml.XmlUtil;
  29 import org.opendaylight.netconf.api.FailedNetconfMessage;
  30 import org.opendaylight.netconf.api.NetconfDocumentedException;
  31 import org.opendaylight.netconf.api.NetconfMessage;
  32 import org.opendaylight.netconf.api.NetconfTerminationReason;
  33 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  34 import org.opendaylight.netconf.client.NetconfClientDispatcher;
  35 import org.opendaylight.netconf.client.NetconfClientSession;
  36 import org.opendaylight.netconf.client.NetconfClientSessionListener;
  37 import org.opendaylight.netconf.client.conf.NetconfClientConfiguration;
  38 import org.opendaylight.netconf.client.conf.NetconfReconnectingClientConfiguration;
  39 import org.opendaylight.netconf.sal.connect.api.RemoteDevice;
  40 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceCommunicator;
  41 import org.opendaylight.netconf.sal.connect.netconf.util.NetconfMessageTransformUtil;
  42 import org.opendaylight.netconf.sal.connect.util.RemoteDeviceId;
  43 import org.opendaylight.yangtools.yang.common.QName;
  44 import org.opendaylight.yangtools.yang.common.RpcError;
  45 import org.opendaylight.yangtools.yang.common.RpcResult;
  46 import org.opendaylight.yangtools.yang.common.RpcResultBuilder;
  47 import org.slf4j.Logger;
  48 import org.slf4j.LoggerFactory;
  49
  50 public class NetconfDeviceCommunicator implements NetconfClientSessionListener, RemoteDeviceCommunicator<NetconfMessage> {
  51
  52     private static final Logger LOG = LoggerFactory.getLogger(NetconfDeviceCommunicator.class);
  53
  54     protected final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice;
  55     private final Optional<UserPreferences> overrideNetconfCapabilities;
  56     protected final RemoteDeviceId id;
  57     private final Lock sessionLock = new ReentrantLock();
  58
  59     private final Semaphore semaphore;
  60     private final int concurentRpcMsgs;
  61
  62     private final Queue<Request> requests = new ArrayDeque<>();
  63     private NetconfClientSession session;
  64
  65     private Future<?> initFuture;
  66     private final SettableFuture<NetconfDeviceCapabilities> firstConnectionFuture;
  67
  68     // isSessionClosing indicates a close operation on the session is issued and
  69     // tearDown will surely be called later to finish the close.
  70     // Used to allow only one thread to enter tearDown and other threads should
  71     // NOT enter it simultaneously and should end its close operation without
  72     // calling tearDown to release the locks they hold to avoid deadlock.
  73     private final AtomicBoolean isSessionClosing = new AtomicBoolean(false);
  74
  75     public Boolean isSessionClosing() {
  76         return isSessionClosing.get();
  77     }
  78
  79     public NetconfDeviceCommunicator(final RemoteDeviceId id, final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  80             final UserPreferences NetconfSessionPreferences, final int rpcMessageLimit) {
  81         this(id, remoteDevice, Optional.of(NetconfSessionPreferences), rpcMessageLimit);
  82     }
  83
  84     public NetconfDeviceCommunicator(final RemoteDeviceId id,
  85                                      final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  86                                      final int rpcMessageLimit) {
  87         this(id, remoteDevice, Optional.<UserPreferences>absent(), rpcMessageLimit);
  88     }
  89
  90     private NetconfDeviceCommunicator(final RemoteDeviceId id, final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  91                                       final Optional<UserPreferences> overrideNetconfCapabilities, final int rpcMessageLimit) {
  92         this.concurentRpcMsgs = rpcMessageLimit;
  93         this.id = id;
  94         this.remoteDevice = remoteDevice;
  95         this.overrideNetconfCapabilities = overrideNetconfCapabilities;
  96         this.firstConnectionFuture = SettableFuture.create();
  97         this.semaphore = rpcMessageLimit > 0 ? new Semaphore(rpcMessageLimit) : null;
  98     }
  99
 100     @Override
 101     public void onSessionUp(final NetconfClientSession session) {
 102         sessionLock.lock();
 103         try {
 104             LOG.debug("{}: Session established", id);
 105             this.session = session;
 106
 107             NetconfSessionPreferences netconfSessionPreferences =
 108                                              NetconfSessionPreferences.fromNetconfSession(session);
 109             LOG.trace("{}: Session advertised capabilities: {}", id,
 110                     netconfSessionPreferences);
 111
 112             if (overrideNetconfCapabilities.isPresent()) {
 113                 final NetconfSessionPreferences sessionPreferences = overrideNetconfCapabilities
 114                         .get().getSessionPreferences();
 115                 netconfSessionPreferences = overrideNetconfCapabilities.get().moduleBasedCapsOverrided()
 116                         ? netconfSessionPreferences.replaceModuleCaps(sessionPreferences)
 117                         : netconfSessionPreferences.addModuleCaps(sessionPreferences);
 118
 119                 netconfSessionPreferences = overrideNetconfCapabilities.get().nonModuleBasedCapsOverrided()
 120                         ? netconfSessionPreferences.replaceNonModuleCaps(sessionPreferences)
 121                         : netconfSessionPreferences.addNonModuleCaps(sessionPreferences);
 122                 LOG.debug("{}: Session capabilities overridden, capabilities that will be used: {}", id,
 123                         netconfSessionPreferences);
 124             }
 125
 126             remoteDevice.onRemoteSessionUp(netconfSessionPreferences, this);
 127             if (!firstConnectionFuture.isDone()) {
 128                 firstConnectionFuture.set(netconfSessionPreferences.getNetconfDeviceCapabilities());
 129             }
 130         }
 131         finally {
 132             sessionLock.unlock();
 133         }
 134     }
 135
 136     /**
 137      *
 138      * @param dispatcher
 139      * @param config
 140      * @return future that returns succes on first succesfull connection and failure when the underlying
 141      * reconnecting strategy runs out of reconnection attempts
 142      */
 143     public ListenableFuture<NetconfDeviceCapabilities> initializeRemoteConnection(final NetconfClientDispatcher dispatcher, final NetconfClientConfiguration config) {
 144         if(config instanceof NetconfReconnectingClientConfiguration) {
 145             initFuture = dispatcher.createReconnectingClient((NetconfReconnectingClientConfiguration) config);
 146         } else {
 147             initFuture = dispatcher.createClient(config);
 148         }
 149
 150
 151         initFuture.addListener(future -> {
 152             if (!future.isSuccess() && !future.isCancelled()) {
 153                 LOG.debug("{}: Connection failed", id, future.cause());
 154                 NetconfDeviceCommunicator.this.remoteDevice.onRemoteSessionFailed(future.cause());
 155                 if (firstConnectionFuture.isDone()) {
 156                     firstConnectionFuture.setException(future.cause());
 157                 }
 158             }
 159         });
 160         return firstConnectionFuture;
 161     }
 162
 163     public void disconnect() {
 164         // If session is already in closing, no need to close it again
 165         if(session != null && isSessionClosing.compareAndSet(false, true)) {
 166             session.close();
 167         }
 168     }
 169
 170     private void tearDown(final String reason) {
 171         if (!isSessionClosing()) {
 172             LOG.warn("It's curious that no one to close the session but tearDown is called!");
 173         }
 174         LOG.debug("Tearing down {}", reason);
 175         final List<UncancellableFuture<RpcResult<NetconfMessage>>> futuresToCancel = Lists.newArrayList();
 176         sessionLock.lock();
 177         try {
 178             if( session != null ) {
 179                 session = null;
 180
 181                 /*
 182                  * Walk all requests, check if they have been executing
 183                  * or cancelled and remove them from the queue.
 184                  */
 185                 final Iterator<Request> it = requests.iterator();
 186                 while (it.hasNext()) {
 187                     final Request r = it.next();
 188                     if (r.future.isUncancellable()) {
 189                         futuresToCancel.add( r.future );
 190                         it.remove();
 191                     } else if (r.future.isCancelled()) {
 192                         // This just does some house-cleaning
 193                         it.remove();
 194                     }
 195                 }
 196
 197                 remoteDevice.onRemoteSessionDown();
 198             }
 199         }
 200         finally {
 201             sessionLock.unlock();
 202         }
 203
 204         // Notify pending request futures outside of the sessionLock to avoid unnecessarily
 205         // blocking the caller.
 206         for (final UncancellableFuture<RpcResult<NetconfMessage>> future : futuresToCancel) {
 207             if( Strings.isNullOrEmpty( reason ) ) {
 208                 future.set( createSessionDownRpcResult() );
 209             } else {
 210                 future.set( createErrorRpcResult( RpcError.ErrorType.TRANSPORT, reason ) );
 211             }
 212         }
 213
 214         isSessionClosing.set(false);
 215     }
 216
 217     private RpcResult<NetconfMessage> createSessionDownRpcResult() {
 218         return createErrorRpcResult( RpcError.ErrorType.TRANSPORT,
 219                              String.format( "The netconf session to %1$s is disconnected", id.getName() ) );
 220     }
 221
 222     private static RpcResult<NetconfMessage> createErrorRpcResult(final RpcError.ErrorType errorType,
 223             final String message) {
 224         return RpcResultBuilder.<NetconfMessage>failed()
 225                 .withError(errorType, NetconfDocumentedException.ErrorTag.OPERATION_FAILED.getTagValue(), message).build();
 226     }
 227
 228     @Override
 229     public void onSessionDown(final NetconfClientSession session, final Exception e) {
 230         // If session is already in closing, no need to call tearDown again.
 231         if (isSessionClosing.compareAndSet(false, true)) {
 232             LOG.warn("{}: Session went down", id, e);
 233             tearDown( null );
 234         }
 235     }
 236
 237     @Override
 238     public void onSessionTerminated(final NetconfClientSession session, final NetconfTerminationReason reason) {
 239         // onSessionTerminated is called directly by disconnect, no need to compare and set isSessionClosing.
 240         LOG.warn("{}: Session terminated {}", id, reason);
 241         tearDown( reason.getErrorMessage() );
 242     }
 243
 244     @Override
 245     public void close() {
 246         // Cancel reconnect if in progress
 247         if(initFuture != null) {
 248             initFuture.cancel(false);
 249         }
 250         // Disconnect from device
 251         // tear down not necessary, called indirectly by the close in disconnect()
 252         disconnect();
 253     }
 254
 255     @Override
 256     public void onMessage(final NetconfClientSession session, final NetconfMessage message) {
 257         /*
 258          * Dispatch between notifications and messages. Messages need to be processed
 259          * with lock held, notifications do not.
 260          */
 261         if (isNotification(message)) {
 262             processNotification(message);
 263         } else {
 264             processMessage(message);
 265         }
 266     }
 267
 268     private void processMessage(final NetconfMessage message) {
 269         Request request = null;
 270         sessionLock.lock();
 271
 272         try {
 273             request = requests.peek();
 274             if (request != null && request.future.isUncancellable()) {
 275                 requests.poll();
 276                 // we have just removed one request from the queue
 277                 // we can also release one permit
 278                 if(semaphore != null) {
 279                     semaphore.release();
 280                 }
 281             } else {
 282                 request = null;
 283                 LOG.warn("{}: Ignoring unsolicited message {}", id,
 284                         msgToS(message));
 285             }
 286         }
 287         finally {
 288             sessionLock.unlock();
 289         }
 290
 291         if( request != null ) {
 292
 293             if (FailedNetconfMessage.class.isInstance(message)) {
 294                 request.future.set(NetconfMessageTransformUtil.toRpcResult((FailedNetconfMessage) message));
 295                 return;
 296             }
 297
 298             LOG.debug("{}: Message received {}", id, message);
 299
 300             if(LOG.isTraceEnabled()) {
 301                 LOG.trace( "{}: Matched request: {} to response: {}", id, msgToS( request.request ), msgToS( message ) );
 302             }
 303
 304             try {
 305                 NetconfMessageTransformUtil.checkValidReply( request.request, message );
 306             } catch (final NetconfDocumentedException e) {
 307                 LOG.warn(
 308                         "{}: Invalid request-reply match, reply message contains different message-id, request: {}, response: {}",
 309                         id, msgToS(request.request), msgToS(message), e);
 310
 311                 request.future.set( RpcResultBuilder.<NetconfMessage>failed()
 312                         .withRpcError( NetconfMessageTransformUtil.toRpcError( e ) ).build() );
 313
 314                 //recursively processing message to eventually find matching request
 315                 processMessage(message);
 316
 317                 return;
 318             }
 319
 320             try {
 321                 NetconfMessageTransformUtil.checkSuccessReply(message);
 322             } catch(final NetconfDocumentedException e) {
 323                 LOG.warn(
 324                         "{}: Error reply from remote device, request: {}, response: {}",
 325                         id, msgToS(request.request), msgToS(message), e);
 326
 327                 request.future.set( RpcResultBuilder.<NetconfMessage>failed()
 328                         .withRpcError( NetconfMessageTransformUtil.toRpcError( e ) ).build() );
 329                 return;
 330             }
 331
 332             request.future.set( RpcResultBuilder.success( message ).build() );
 333         }
 334     }
 335
 336     private static String msgToS(final NetconfMessage msg) {
 337         return XmlUtil.toString(msg.getDocument());
 338     }
 339
 340     @Override
 341     public ListenableFuture<RpcResult<NetconfMessage>> sendRequest(final NetconfMessage message, final QName rpc) {
 342         sessionLock.lock();
 343
 344         if (semaphore != null && !semaphore.tryAcquire()) {
 345             LOG.warn("Limit of concurrent rpc messages was reached (limit :" +
 346                     concurentRpcMsgs + "). Rpc reply message is needed. Discarding request of Netconf device with id" + id.getName());
 347             sessionLock.unlock();
 348             return Futures.immediateFailedFuture(new NetconfDocumentedException("Limit of rpc messages was reached (Limit :" +
 349                     concurentRpcMsgs + ") waiting for emptying the queue of Netconf device with id" + id.getName()));
 350         }
 351
 352         try {
 353             return sendRequestWithLock(message, rpc);
 354         } finally {
 355             sessionLock.unlock();
 356         }
 357     }
 358
 359     private ListenableFuture<RpcResult<NetconfMessage>> sendRequestWithLock(
 360                                                final NetconfMessage message, final QName rpc) {
 361         if(LOG.isTraceEnabled()) {
 362             LOG.trace("{}: Sending message {}", id, msgToS(message));
 363         }
 364
 365         if (session == null) {
 366             LOG.warn("{}: Session is disconnected, failing RPC request {}",
 367                     id, message);
 368             return Futures.immediateFuture( createSessionDownRpcResult() );
 369         }
 370
 371         final Request req = new Request(new UncancellableFuture<>(true), message);
 372         requests.add(req);
 373
 374         session.sendMessage(req.request).addListener(future -> {
 375             if( !future.isSuccess() ) {
 376                 // We expect that a session down will occur at this point
 377                 LOG.debug("{}: Failed to send request {}", id,
 378                         XmlUtil.toString(req.request.getDocument()),
 379                         future.cause());
 380
 381                 if( future.cause() != null ) {
 382                     req.future.set( createErrorRpcResult( RpcError.ErrorType.TRANSPORT,
 383                                                           future.cause().getLocalizedMessage() ) );
 384                 } else {
 385                     req.future.set( createSessionDownRpcResult() ); // assume session is down
 386                 }
 387                 req.future.setException( future.cause() );
 388             }
 389             else {
 390                 LOG.trace("Finished sending request {}", req.request);
 391             }
 392         });
 393
 394         return req.future;
 395     }
 396
 397     private void processNotification(final NetconfMessage notification) {
 398         if(LOG.isTraceEnabled()) {
 399             LOG.trace("{}: Notification received: {}", id, notification);
 400         }
 401
 402         remoteDevice.onNotification(notification);
 403     }
 404
 405     private static boolean isNotification(final NetconfMessage message) {
 406         if (message.getDocument() == null) {
 407             // We have no message, which mean we have a FailedNetconfMessage
 408             return false;
 409         }
 410         final XmlElement xmle = XmlElement.fromDomDocument(message.getDocument());
 411         return XmlNetconfConstants.NOTIFICATION_ELEMENT_NAME.equals(xmle.getName()) ;
 412     }
 413
 414     private static final class Request {
 415         final UncancellableFuture<RpcResult<NetconfMessage>> future;
 416         final NetconfMessage request;
 417
 418         private Request(final UncancellableFuture<RpcResult<NetconfMessage>> future,
 419                         final NetconfMessage request) {
 420             this.future = future;
 421             this.request = request;
 422         }
 423     }
 424 }