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.Strings;
  11 import com.google.common.util.concurrent.ListenableFuture;
  12 import com.google.common.util.concurrent.SettableFuture;
  13 import io.netty.util.concurrent.Future;
  14 import java.io.EOFException;
  15 import java.util.ArrayDeque;
  16 import java.util.ArrayList;
  17 import java.util.Iterator;
  18 import java.util.List;
  19 import java.util.Optional;
  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.ErrorTag;
  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
  51         implements NetconfClientSessionListener, RemoteDeviceCommunicator<NetconfMessage> {
  52
  53     private static final Logger LOG = LoggerFactory.getLogger(NetconfDeviceCommunicator.class);
  54
  55     protected final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice;
  56     private final Optional<UserPreferences> overrideNetconfCapabilities;
  57     protected final RemoteDeviceId id;
  58     private final Lock sessionLock = new ReentrantLock();
  59
  60     private final Semaphore semaphore;
  61     private final int concurentRpcMsgs;
  62
  63     private final Queue<Request> requests = new ArrayDeque<>();
  64     private NetconfClientSession currentSession;
  65
  66     private final SettableFuture<NetconfDeviceCapabilities> firstConnectionFuture;
  67     private Future<?> initFuture;
  68
  69     // isSessionClosing indicates a close operation on the session is issued and
  70     // tearDown will surely be called later to finish the close.
  71     // Used to allow only one thread to enter tearDown and other threads should
  72     // NOT enter it simultaneously and should end its close operation without
  73     // calling tearDown to release the locks they hold to avoid deadlock.
  74     private static final AtomicIntegerFieldUpdater<NetconfDeviceCommunicator> CLOSING_UPDATER =
  75             AtomicIntegerFieldUpdater.newUpdater(NetconfDeviceCommunicator.class, "closing");
  76     private volatile int closing;
  77
  78     public boolean isSessionClosing() {
  79         return closing != 0;
  80     }
  81
  82     public NetconfDeviceCommunicator(
  83             final RemoteDeviceId id,
  84             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  85             final UserPreferences netconfSessionPreferences, final int rpcMessageLimit) {
  86         this(id, remoteDevice, Optional.of(netconfSessionPreferences), rpcMessageLimit);
  87     }
  88
  89     public NetconfDeviceCommunicator(
  90             final RemoteDeviceId id,
  91             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  92             final int rpcMessageLimit) {
  93         this(id, remoteDevice, Optional.empty(), rpcMessageLimit);
  94     }
  95
  96     private NetconfDeviceCommunicator(
  97             final RemoteDeviceId id,
  98             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  99             final Optional<UserPreferences> overrideNetconfCapabilities, final int rpcMessageLimit) {
 100         this.concurentRpcMsgs = rpcMessageLimit;
 101         this.id = id;
 102         this.remoteDevice = remoteDevice;
 103         this.overrideNetconfCapabilities = overrideNetconfCapabilities;
 104         this.firstConnectionFuture = SettableFuture.create();
 105         this.semaphore = rpcMessageLimit > 0 ? new Semaphore(rpcMessageLimit) : null;
 106     }
 107
 108     @Override
 109     public void onSessionUp(final NetconfClientSession session) {
 110         sessionLock.lock();
 111         try {
 112             LOG.debug("{}: Session established", id);
 113             currentSession = session;
 114
 115             NetconfSessionPreferences netconfSessionPreferences =
 116                                              NetconfSessionPreferences.fromNetconfSession(session);
 117             LOG.trace("{}: Session advertised capabilities: {}", id,
 118                     netconfSessionPreferences);
 119
 120             if (overrideNetconfCapabilities.isPresent()) {
 121                 final NetconfSessionPreferences sessionPreferences = overrideNetconfCapabilities
 122                         .get().getSessionPreferences();
 123                 netconfSessionPreferences = overrideNetconfCapabilities.get().moduleBasedCapsOverrided()
 124                         ? netconfSessionPreferences.replaceModuleCaps(sessionPreferences)
 125                         : netconfSessionPreferences.addModuleCaps(sessionPreferences);
 126
 127                 netconfSessionPreferences = overrideNetconfCapabilities.get().nonModuleBasedCapsOverrided()
 128                         ? netconfSessionPreferences.replaceNonModuleCaps(sessionPreferences)
 129                         : netconfSessionPreferences.addNonModuleCaps(sessionPreferences);
 130                 LOG.debug("{}: Session capabilities overridden, capabilities that will be used: {}", id,
 131                         netconfSessionPreferences);
 132             }
 133
 134             remoteDevice.onRemoteSessionUp(netconfSessionPreferences, this);
 135             if (!firstConnectionFuture.isDone()) {
 136                 firstConnectionFuture.set(netconfSessionPreferences.getNetconfDeviceCapabilities());
 137             }
 138         } finally {
 139             sessionLock.unlock();
 140         }
 141     }
 142
 143     /**
 144      * Initialize remote connection.
 145      *
 146      * @param dispatcher {@code NetconfCLientDispatcher}
 147      * @param config     {@code NetconfClientConfiguration}
 148      * @return a ListenableFuture that returns success on first successful connection and failure when the underlying
 149      *         reconnecting strategy runs out of reconnection attempts
 150      */
 151     public ListenableFuture<NetconfDeviceCapabilities> initializeRemoteConnection(
 152             final NetconfClientDispatcher dispatcher, final NetconfClientConfiguration config) {
 153         if (config instanceof NetconfReconnectingClientConfiguration) {
 154             initFuture = dispatcher.createReconnectingClient((NetconfReconnectingClientConfiguration) config);
 155         } else {
 156             initFuture = dispatcher.createClient(config);
 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, ErrorTag.OPERATION_FAILED.elementBody(), 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             if (exception instanceof EOFException) {
 239                 LOG.info("{}: Session went down: {}", id, exception.getMessage());
 240             } else {
 241                 LOG.warn("{}: Session went down", id, exception);
 242             }
 243             tearDown(null);
 244         }
 245     }
 246
 247     @Override
 248     public void onSessionTerminated(final NetconfClientSession session, final NetconfTerminationReason reason) {
 249         // onSessionTerminated is called directly by disconnect, no need to compare and set isSessionClosing.
 250         LOG.warn("{}: Session terminated {}", id, reason);
 251         tearDown(reason.getErrorMessage());
 252     }
 253
 254     @Override
 255     public void close() {
 256         // Cancel reconnect if in progress
 257         if (initFuture != null) {
 258             initFuture.cancel(false);
 259         }
 260         // Disconnect from device
 261         // tear down not necessary, called indirectly by the close in disconnect()
 262         disconnect();
 263     }
 264
 265     @Override
 266     public void onMessage(final NetconfClientSession session, final NetconfMessage message) {
 267         /*
 268          * Dispatch between notifications and messages. Messages need to be processed
 269          * with lock held, notifications do not.
 270          */
 271         if (isNotification(message)) {
 272             processNotification(message);
 273         } else {
 274             processMessage(message);
 275         }
 276     }
 277
 278     private void processMessage(final NetconfMessage message) {
 279         Request request = null;
 280         sessionLock.lock();
 281
 282         try {
 283             request = requests.peek();
 284             if (request != null && request.future.isUncancellable()) {
 285                 request = requests.poll();
 286                 // we have just removed one request from the queue
 287                 // we can also release one permit
 288                 if (semaphore != null) {
 289                     semaphore.release();
 290                 }
 291             } else {
 292                 request = null;
 293                 LOG.warn("{}: Ignoring unsolicited message {}", id,
 294                         msgToS(message));
 295             }
 296         } finally {
 297             sessionLock.unlock();
 298         }
 299
 300         if (request != null) {
 301
 302             if (FailedNetconfMessage.class.isInstance(message)) {
 303                 request.future.set(NetconfMessageTransformUtil.toRpcResult((FailedNetconfMessage) message));
 304                 return;
 305             }
 306
 307             LOG.debug("{}: Message received {}", id, message);
 308
 309             if (LOG.isTraceEnabled()) {
 310                 LOG.trace("{}: Matched request: {} to response: {}", id, msgToS(request.request), msgToS(message));
 311             }
 312
 313             try {
 314                 NetconfMessageTransformUtil.checkValidReply(request.request, message);
 315             } catch (final NetconfDocumentedException e) {
 316                 LOG.warn(
 317                         "{}: Invalid request-reply match,"
 318                                 + "reply message contains different message-id, request: {}, response: {}",
 319                         id, msgToS(request.request), msgToS(message), e);
 320
 321                 request.future.set(RpcResultBuilder.<NetconfMessage>failed()
 322                         .withRpcError(NetconfMessageTransformUtil.toRpcError(e)).build());
 323
 324                 //recursively processing message to eventually find matching request
 325                 processMessage(message);
 326
 327                 return;
 328             }
 329
 330             try {
 331                 NetconfMessageTransformUtil.checkSuccessReply(message);
 332             } catch (final NetconfDocumentedException e) {
 333                 LOG.warn(
 334                         "{}: Error reply from remote device, request: {}, response: {}",
 335                         id, msgToS(request.request), msgToS(message), e);
 336
 337                 request.future.set(RpcResultBuilder.<NetconfMessage>failed()
 338                         .withRpcError(NetconfMessageTransformUtil.toRpcError(e)).build());
 339                 return;
 340             }
 341
 342             request.future.set(RpcResultBuilder.success(message).build());
 343         }
 344     }
 345
 346     private static String msgToS(final NetconfMessage msg) {
 347         return XmlUtil.toString(msg.getDocument());
 348     }
 349
 350     @Override
 351     public ListenableFuture<RpcResult<NetconfMessage>> sendRequest(final NetconfMessage message, final QName rpc) {
 352         sessionLock.lock();
 353         try {
 354             if (semaphore != null && !semaphore.tryAcquire()) {
 355                 LOG.warn("Limit of concurrent rpc messages was reached (limit: {}). Rpc reply message is needed. "
 356                     + "Discarding request of Netconf device with id: {}", concurentRpcMsgs, id.getName());
 357                 return FluentFutures.immediateFailedFluentFuture(new NetconfDocumentedException(
 358                         "Limit of rpc messages was reached (Limit :" + concurentRpcMsgs
 359                         + ") waiting for emptying the queue of Netconf device with id: " + id.getName()));
 360             }
 361
 362             return sendRequestWithLock(message, rpc);
 363         } finally {
 364             sessionLock.unlock();
 365         }
 366     }
 367
 368     private ListenableFuture<RpcResult<NetconfMessage>> sendRequestWithLock(final NetconfMessage message,
 369                                                                             final QName rpc) {
 370         if (LOG.isTraceEnabled()) {
 371             LOG.trace("{}: Sending message {}", id, msgToS(message));
 372         }
 373
 374         if (currentSession == null) {
 375             LOG.warn("{}: Session is disconnected, failing RPC request {}",
 376                     id, message);
 377             return FluentFutures.immediateFluentFuture(createSessionDownRpcResult());
 378         }
 379
 380         final Request req = new Request(new UncancellableFuture<>(true), message);
 381         requests.add(req);
 382
 383         currentSession.sendMessage(req.request).addListener(future -> {
 384             if (!future.isSuccess()) {
 385                 // We expect that a session down will occur at this point
 386                 LOG.debug("{}: Failed to send request {}", id,
 387                         XmlUtil.toString(req.request.getDocument()),
 388                         future.cause());
 389
 390                 if (future.cause() != null) {
 391                     req.future.set(createErrorRpcResult(RpcError.ErrorType.TRANSPORT,
 392                             future.cause().getLocalizedMessage()));
 393                 } else {
 394                     req.future.set(createSessionDownRpcResult()); // assume session is down
 395                 }
 396                 req.future.setException(future.cause());
 397             } else {
 398                 LOG.trace("Finished sending request {}", req.request);
 399             }
 400         });
 401
 402         return req.future;
 403     }
 404
 405     private void processNotification(final NetconfMessage notification) {
 406         if (LOG.isTraceEnabled()) {
 407             LOG.trace("{}: Notification received: {}", id, notification);
 408         }
 409
 410         remoteDevice.onNotification(notification);
 411     }
 412
 413     private static boolean isNotification(final NetconfMessage message) {
 414         if (message.getDocument() == null) {
 415             // We have no message, which mean we have a FailedNetconfMessage
 416             return false;
 417         }
 418         final XmlElement xmle = XmlElement.fromDomDocument(message.getDocument());
 419         return XmlNetconfConstants.NOTIFICATION_ELEMENT_NAME.equals(xmle.getName()) ;
 420     }
 421
 422     private static final class Request {
 423         final UncancellableFuture<RpcResult<NetconfMessage>> future;
 424         final NetconfMessage request;
 425
 426         private Request(final UncancellableFuture<RpcResult<NetconfMessage>> future,
 427                         final NetconfMessage request) {
 428             this.future = future;
 429             this.request = request;
 430         }
 431     }
 432
 433     private boolean startClosing() {
 434         return CLOSING_UPDATER.compareAndSet(this, 0, 1);
 435     }
 436 }