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.util.concurrent.FluentFuture;
  13 import com.google.common.util.concurrent.ListenableFuture;
  14 import com.google.common.util.concurrent.SettableFuture;
  15 import io.netty.util.concurrent.Future;
  16 import java.util.ArrayDeque;
  17 import java.util.ArrayList;
  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.AtomicIntegerFieldUpdater;
  23 import java.util.concurrent.locks.Lock;
  24 import java.util.concurrent.locks.ReentrantLock;
  25 import org.opendaylight.netconf.api.FailedNetconfMessage;
  26 import org.opendaylight.netconf.api.NetconfDocumentedException;
  27 import org.opendaylight.netconf.api.NetconfMessage;
  28 import org.opendaylight.netconf.api.NetconfTerminationReason;
  29 import org.opendaylight.netconf.api.xml.XmlElement;
  30 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  31 import org.opendaylight.netconf.api.xml.XmlUtil;
  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.util.concurrent.FluentFutures;
  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
  50         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 currentSession;
  64
  65     private final SettableFuture<NetconfDeviceCapabilities> firstConnectionFuture;
  66     private Future<?> initFuture;
  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 static final AtomicIntegerFieldUpdater<NetconfDeviceCommunicator> CLOSING_UPDATER =
  74             AtomicIntegerFieldUpdater.newUpdater(NetconfDeviceCommunicator.class, "closing");
  75     private volatile int closing;
  76
  77     public boolean isSessionClosing() {
  78         return closing != 0;
  79     }
  80
  81     public NetconfDeviceCommunicator(
  82             final RemoteDeviceId id,
  83             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  84             final UserPreferences netconfSessionPreferences, final int rpcMessageLimit) {
  85         this(id, remoteDevice, Optional.of(netconfSessionPreferences), rpcMessageLimit);
  86     }
  87
  88     public NetconfDeviceCommunicator(
  89             final RemoteDeviceId id,
  90             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  91             final int rpcMessageLimit) {
  92         this(id, remoteDevice, Optional.absent(), rpcMessageLimit);
  93     }
  94
  95     private NetconfDeviceCommunicator(
  96             final RemoteDeviceId id,
  97             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  98             final Optional<UserPreferences> overrideNetconfCapabilities, final int rpcMessageLimit) {
  99         this.concurentRpcMsgs = rpcMessageLimit;
 100         this.id = id;
 101         this.remoteDevice = remoteDevice;
 102         this.overrideNetconfCapabilities = overrideNetconfCapabilities;
 103         this.firstConnectionFuture = SettableFuture.create();
 104         this.semaphore = rpcMessageLimit > 0 ? new Semaphore(rpcMessageLimit) : null;
 105     }
 106
 107     @Override
 108     public void onSessionUp(final NetconfClientSession session) {
 109         sessionLock.lock();
 110         try {
 111             LOG.debug("{}: Session established", id);
 112             currentSession = session;
 113
 114             NetconfSessionPreferences netconfSessionPreferences =
 115                                              NetconfSessionPreferences.fromNetconfSession(session);
 116             LOG.trace("{}: Session advertised capabilities: {}", id,
 117                     netconfSessionPreferences);
 118
 119             if (overrideNetconfCapabilities.isPresent()) {
 120                 final NetconfSessionPreferences sessionPreferences = overrideNetconfCapabilities
 121                         .get().getSessionPreferences();
 122                 netconfSessionPreferences = overrideNetconfCapabilities.get().moduleBasedCapsOverrided()
 123                         ? netconfSessionPreferences.replaceModuleCaps(sessionPreferences)
 124                         : netconfSessionPreferences.addModuleCaps(sessionPreferences);
 125
 126                 netconfSessionPreferences = overrideNetconfCapabilities.get().nonModuleBasedCapsOverrided()
 127                         ? netconfSessionPreferences.replaceNonModuleCaps(sessionPreferences)
 128                         : netconfSessionPreferences.addNonModuleCaps(sessionPreferences);
 129                 LOG.debug("{}: Session capabilities overridden, capabilities that will be used: {}", id,
 130                         netconfSessionPreferences);
 131             }
 132
 133             remoteDevice.onRemoteSessionUp(netconfSessionPreferences, this);
 134             if (!firstConnectionFuture.isDone()) {
 135                 firstConnectionFuture.set(netconfSessionPreferences.getNetconfDeviceCapabilities());
 136             }
 137         } finally {
 138             sessionLock.unlock();
 139         }
 140     }
 141
 142     /**
 143      * Initialize remote connection.
 144      *
 145      * @param dispatcher {@code NetconfCLientDispatcher}
 146      * @param config     {@code NetconfClientConfiguration}
 147      * @return future that returns succes on first succesfull connection and failure when the underlying
 148      *     reconnecting strategy runs out of reconnection attempts
 149      */
 150     public ListenableFuture<NetconfDeviceCapabilities> initializeRemoteConnection(
 151             final NetconfClientDispatcher dispatcher, final NetconfClientConfiguration config) {
 152         if (config instanceof NetconfReconnectingClientConfiguration) {
 153             initFuture = dispatcher.createReconnectingClient((NetconfReconnectingClientConfiguration) config);
 154         } else {
 155             initFuture = dispatcher.createClient(config);
 156         }
 157
 158
 159         initFuture.addListener(future -> {
 160             if (!future.isSuccess() && !future.isCancelled()) {
 161                 LOG.debug("{}: Connection failed", id, future.cause());
 162                 NetconfDeviceCommunicator.this.remoteDevice.onRemoteSessionFailed(future.cause());
 163                 if (firstConnectionFuture.isDone()) {
 164                     firstConnectionFuture.setException(future.cause());
 165                 }
 166             }
 167         });
 168         return firstConnectionFuture;
 169     }
 170
 171     public void disconnect() {
 172         // If session is already in closing, no need to close it again
 173         if (currentSession != null && startClosing() && currentSession.isUp()) {
 174             currentSession.close();
 175         }
 176     }
 177
 178     private void tearDown(final String reason) {
 179         if (!isSessionClosing()) {
 180             LOG.warn("It's curious that no one to close the session but tearDown is called!");
 181         }
 182         LOG.debug("Tearing down {}", reason);
 183         final List<UncancellableFuture<RpcResult<NetconfMessage>>> futuresToCancel = new ArrayList<>();
 184         sessionLock.lock();
 185         try {
 186             if (currentSession != null) {
 187                 currentSession = null;
 188                 /*
 189                  * Walk all requests, check if they have been executing
 190                  * or cancelled and remove them from the queue.
 191                  */
 192                 final Iterator<Request> it = requests.iterator();
 193                 while (it.hasNext()) {
 194                     final Request r = it.next();
 195                     if (r.future.isUncancellable()) {
 196                         futuresToCancel.add(r.future);
 197                         it.remove();
 198                     } else if (r.future.isCancelled()) {
 199                         // This just does some house-cleaning
 200                         it.remove();
 201                     }
 202                 }
 203
 204                 remoteDevice.onRemoteSessionDown();
 205             }
 206         } finally {
 207             sessionLock.unlock();
 208         }
 209
 210         // Notify pending request futures outside of the sessionLock to avoid unnecessarily
 211         // blocking the caller.
 212         for (final UncancellableFuture<RpcResult<NetconfMessage>> future : futuresToCancel) {
 213             if (Strings.isNullOrEmpty(reason)) {
 214                 future.set(createSessionDownRpcResult());
 215             } else {
 216                 future.set(createErrorRpcResult(RpcError.ErrorType.TRANSPORT, reason));
 217             }
 218         }
 219
 220         closing = 0;
 221     }
 222
 223     private RpcResult<NetconfMessage> createSessionDownRpcResult() {
 224         return createErrorRpcResult(RpcError.ErrorType.TRANSPORT,
 225                 String.format("The netconf session to %1$s is disconnected", id.getName()));
 226     }
 227
 228     private static RpcResult<NetconfMessage> createErrorRpcResult(final RpcError.ErrorType errorType,
 229             final String message) {
 230         return RpcResultBuilder.<NetconfMessage>failed()
 231             .withError(errorType, NetconfDocumentedException.ErrorTag.OPERATION_FAILED.getTagValue(), message).build();
 232     }
 233
 234     @Override
 235     public void onSessionDown(final NetconfClientSession session, final Exception exception) {
 236         // If session is already in closing, no need to call tearDown again.
 237         if (startClosing()) {
 238             LOG.warn("{}: Session went down", id, exception);
 239             tearDown(null);
 240         }
 241     }
 242
 243     @Override
 244     public void onSessionTerminated(final NetconfClientSession session, final NetconfTerminationReason reason) {
 245         // onSessionTerminated is called directly by disconnect, no need to compare and set isSessionClosing.
 246         LOG.warn("{}: Session terminated {}", id, reason);
 247         tearDown(reason.getErrorMessage());
 248     }
 249
 250     @Override
 251     public void close() {
 252         // Cancel reconnect if in progress
 253         if (initFuture != null) {
 254             initFuture.cancel(false);
 255         }
 256         // Disconnect from device
 257         // tear down not necessary, called indirectly by the close in disconnect()
 258         disconnect();
 259     }
 260
 261     @Override
 262     public void onMessage(final NetconfClientSession session, final NetconfMessage message) {
 263         /*
 264          * Dispatch between notifications and messages. Messages need to be processed
 265          * with lock held, notifications do not.
 266          */
 267         if (isNotification(message)) {
 268             processNotification(message);
 269         } else {
 270             processMessage(message);
 271         }
 272     }
 273
 274     private void processMessage(final NetconfMessage message) {
 275         Request request = null;
 276         sessionLock.lock();
 277
 278         try {
 279             request = requests.peek();
 280             if (request != null && request.future.isUncancellable()) {
 281                 request = requests.poll();
 282                 // we have just removed one request from the queue
 283                 // we can also release one permit
 284                 if (semaphore != null) {
 285                     semaphore.release();
 286                 }
 287             } else {
 288                 request = null;
 289                 LOG.warn("{}: Ignoring unsolicited message {}", id,
 290                         msgToS(message));
 291             }
 292         } finally {
 293             sessionLock.unlock();
 294         }
 295
 296         if (request != null) {
 297
 298             if (FailedNetconfMessage.class.isInstance(message)) {
 299                 request.future.set(NetconfMessageTransformUtil.toRpcResult((FailedNetconfMessage) message));
 300                 return;
 301             }
 302
 303             LOG.debug("{}: Message received {}", id, message);
 304
 305             if (LOG.isTraceEnabled()) {
 306                 LOG.trace("{}: Matched request: {} to response: {}", id, msgToS(request.request), msgToS(message));
 307             }
 308
 309             try {
 310                 NetconfMessageTransformUtil.checkValidReply(request.request, message);
 311             } catch (final NetconfDocumentedException e) {
 312                 LOG.warn(
 313                         "{}: Invalid request-reply match,"
 314                                 + "reply message contains different message-id, request: {}, response: {}",
 315                         id, msgToS(request.request), msgToS(message), e);
 316
 317                 request.future.set(RpcResultBuilder.<NetconfMessage>failed()
 318                         .withRpcError(NetconfMessageTransformUtil.toRpcError(e)).build());
 319
 320                 //recursively processing message to eventually find matching request
 321                 processMessage(message);
 322
 323                 return;
 324             }
 325
 326             try {
 327                 NetconfMessageTransformUtil.checkSuccessReply(message);
 328             } catch (final NetconfDocumentedException e) {
 329                 LOG.warn(
 330                         "{}: Error reply from remote device, request: {}, response: {}",
 331                         id, msgToS(request.request), msgToS(message), e);
 332
 333                 request.future.set(RpcResultBuilder.<NetconfMessage>failed()
 334                         .withRpcError(NetconfMessageTransformUtil.toRpcError(e)).build());
 335                 return;
 336             }
 337
 338             request.future.set(RpcResultBuilder.success(message).build());
 339         }
 340     }
 341
 342     private static String msgToS(final NetconfMessage msg) {
 343         return XmlUtil.toString(msg.getDocument());
 344     }
 345
 346     @Override
 347     public FluentFuture<RpcResult<NetconfMessage>> sendRequest(final NetconfMessage message, final QName rpc) {
 348         sessionLock.lock();
 349         try {
 350             if (semaphore != null && !semaphore.tryAcquire()) {
 351                 LOG.warn("Limit of concurrent rpc messages was reached (limit: {}). Rpc reply message is needed. "
 352                     + "Discarding request of Netconf device with id {}", concurentRpcMsgs, id.getName());
 353                 return FluentFutures.immediateFailedFluentFuture(new NetconfDocumentedException(
 354                         "Limit of rpc messages was reached (Limit :" + concurentRpcMsgs
 355                         + ") waiting for emptying the queue of Netconf device with id" + id.getName()));
 356             }
 357
 358             return sendRequestWithLock(message, rpc);
 359         } finally {
 360             sessionLock.unlock();
 361         }
 362     }
 363
 364     private FluentFuture<RpcResult<NetconfMessage>> sendRequestWithLock(final NetconfMessage message,
 365                                                                             final QName rpc) {
 366         if (LOG.isTraceEnabled()) {
 367             LOG.trace("{}: Sending message {}", id, msgToS(message));
 368         }
 369
 370         if (currentSession == null) {
 371             LOG.warn("{}: Session is disconnected, failing RPC request {}",
 372                     id, message);
 373             return FluentFutures.immediateFluentFuture(createSessionDownRpcResult());
 374         }
 375
 376         final Request req = new Request(new UncancellableFuture<>(true), message);
 377         requests.add(req);
 378
 379         currentSession.sendMessage(req.request).addListener(future -> {
 380             if (!future.isSuccess()) {
 381                 // We expect that a session down will occur at this point
 382                 LOG.debug("{}: Failed to send request {}", id,
 383                         XmlUtil.toString(req.request.getDocument()),
 384                         future.cause());
 385
 386                 if (future.cause() != null) {
 387                     req.future.set(createErrorRpcResult(RpcError.ErrorType.TRANSPORT,
 388                             future.cause().getLocalizedMessage()));
 389                 } else {
 390                     req.future.set(createSessionDownRpcResult()); // assume session is down
 391                 }
 392                 req.future.setException(future.cause());
 393             } else {
 394                 LOG.trace("Finished sending request {}", req.request);
 395             }
 396         });
 397
 398         return req.future;
 399     }
 400
 401     private void processNotification(final NetconfMessage notification) {
 402         if (LOG.isTraceEnabled()) {
 403             LOG.trace("{}: Notification received: {}", id, notification);
 404         }
 405
 406         remoteDevice.onNotification(notification);
 407     }
 408
 409     private static boolean isNotification(final NetconfMessage message) {
 410         if (message.getDocument() == null) {
 411             // We have no message, which mean we have a FailedNetconfMessage
 412             return false;
 413         }
 414         final XmlElement xmle = XmlElement.fromDomDocument(message.getDocument());
 415         return XmlNetconfConstants.NOTIFICATION_ELEMENT_NAME.equals(xmle.getName()) ;
 416     }
 417
 418     private static final class Request {
 419         final UncancellableFuture<RpcResult<NetconfMessage>> future;
 420         final NetconfMessage request;
 421
 422         private Request(final UncancellableFuture<RpcResult<NetconfMessage>> future,
 423                         final NetconfMessage request) {
 424             this.future = future;
 425             this.request = request;
 426         }
 427     }
 428
 429     private boolean startClosing() {
 430         return CLOSING_UPDATER.compareAndSet(this, 0, 1);
 431     }
 432 }