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