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 import org.opendaylight.controller.config.util.xml.XmlElement;
  26 import org.opendaylight.controller.config.util.xml.XmlUtil;
  27 import org.opendaylight.netconf.api.NetconfDocumentedException;
  28 import org.opendaylight.netconf.api.NetconfMessage;
  29 import org.opendaylight.netconf.api.NetconfTerminationReason;
  30 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  31 import org.opendaylight.netconf.client.NetconfClientDispatcher;
  32 import org.opendaylight.netconf.client.NetconfClientSession;
  33 import org.opendaylight.netconf.client.NetconfClientSessionListener;
  34 import org.opendaylight.netconf.client.conf.NetconfClientConfiguration;
  35 import org.opendaylight.netconf.client.conf.NetconfReconnectingClientConfiguration;
  36 import org.opendaylight.netconf.sal.connect.api.RemoteDevice;
  37 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceCommunicator;
  38 import org.opendaylight.netconf.sal.connect.netconf.util.NetconfMessageTransformUtil;
  39 import org.opendaylight.netconf.sal.connect.util.RemoteDeviceId;
  40 import org.opendaylight.yangtools.yang.common.QName;
  41 import org.opendaylight.yangtools.yang.common.RpcError;
  42 import org.opendaylight.yangtools.yang.common.RpcResult;
  43 import org.opendaylight.yangtools.yang.common.RpcResultBuilder;
  44 import org.slf4j.Logger;
  45 import org.slf4j.LoggerFactory;
  46
  47 public class NetconfDeviceCommunicator
  48         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 final SettableFuture<NetconfDeviceCapabilities> firstConnectionFuture;
  65
  66     // isSessionClosing indicates a close operation on the session is issued and
  67     // tearDown will surely be called later to finish the close.
  68     // Used to allow only one thread to enter tearDown and other threads should
  69     // NOT enter it simultaneously and should end its close operation without
  70     // calling tearDown to release the locks they hold to avoid deadlock.
  71     private final AtomicBoolean isSessionClosing = new AtomicBoolean(false);
  72
  73     public Boolean isSessionClosing() {
  74         return isSessionClosing.get();
  75     }
  76
  77     public NetconfDeviceCommunicator(
  78             final RemoteDeviceId id,
  79             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(
  85             final RemoteDeviceId id,
  86             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  87             final int rpcMessageLimit) {
  88         this(id, remoteDevice, Optional.<UserPreferences>absent(), rpcMessageLimit);
  89     }
  90
  91     private NetconfDeviceCommunicator(
  92             final RemoteDeviceId id,
  93             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  94             final Optional<UserPreferences> overrideNetconfCapabilities, final int rpcMessageLimit) {
  95         this.concurentRpcMsgs = rpcMessageLimit;
  96         this.id = id;
  97         this.remoteDevice = remoteDevice;
  98         this.overrideNetconfCapabilities = overrideNetconfCapabilities;
  99         this.firstConnectionFuture = SettableFuture.create();
 100         this.semaphore = rpcMessageLimit > 0 ? new Semaphore(rpcMessageLimit) : null;
 101     }
 102
 103     @Override
 104     public void onSessionUp(final NetconfClientSession session) {
 105         sessionLock.lock();
 106         try {
 107             LOG.debug("{}: Session established", id);
 108             this.session = session;
 109
 110             NetconfSessionPreferences netconfSessionPreferences =
 111                                              NetconfSessionPreferences.fromNetconfSession(session);
 112             LOG.trace("{}: Session advertised capabilities: {}", id,
 113                     netconfSessionPreferences);
 114
 115             if (overrideNetconfCapabilities.isPresent()) {
 116                 final NetconfSessionPreferences sessionPreferences = overrideNetconfCapabilities
 117                         .get().getSessionPreferences();
 118                 netconfSessionPreferences = overrideNetconfCapabilities.get().moduleBasedCapsOverrided()
 119                         ? netconfSessionPreferences.replaceModuleCaps(sessionPreferences)
 120                         : netconfSessionPreferences.addModuleCaps(sessionPreferences);
 121
 122                 netconfSessionPreferences = overrideNetconfCapabilities.get().nonModuleBasedCapsOverrided()
 123                         ? netconfSessionPreferences.replaceNonModuleCaps(sessionPreferences)
 124                         : netconfSessionPreferences.addNonModuleCaps(sessionPreferences);
 125                 LOG.debug("{}: Session capabilities overridden, capabilities that will be used: {}", id,
 126                         netconfSessionPreferences);
 127             }
 128
 129             remoteDevice.onRemoteSessionUp(netconfSessionPreferences, this);
 130             if (!firstConnectionFuture.isDone()) {
 131                 firstConnectionFuture.set(netconfSessionPreferences.getNetconfDeviceCapabilities());
 132             }
 133         } finally {
 134             sessionLock.unlock();
 135         }
 136     }
 137
 138     /**
 139      * Initialize remote connection.
 140      *
 141      * @param dispatcher {@code NetconfCLientDispatcher}
 142      * @param config     {@code NetconfClientConfiguration}
 143      * @return future that returns succes on first succesfull connection and failure when the underlying
 144      *     reconnecting strategy runs out of reconnection attempts
 145      */
 146     public ListenableFuture<NetconfDeviceCapabilities> initializeRemoteConnection(
 147             final NetconfClientDispatcher dispatcher, final NetconfClientConfiguration config) {
 148         if (config instanceof NetconfReconnectingClientConfiguration) {
 149             initFuture = dispatcher.createReconnectingClient((NetconfReconnectingClientConfiguration) config);
 150         } else {
 151             initFuture = dispatcher.createClient(config);
 152         }
 153
 154
 155         initFuture.addListener(future -> {
 156             if (!future.isSuccess() && !future.isCancelled()) {
 157                 LOG.debug("{}: Connection failed", id, future.cause());
 158                 NetconfDeviceCommunicator.this.remoteDevice.onRemoteSessionFailed(future.cause());
 159                 if (firstConnectionFuture.isDone()) {
 160                     firstConnectionFuture.setException(future.cause());
 161                 }
 162             }
 163         });
 164         return firstConnectionFuture;
 165     }
 166
 167     public void disconnect() {
 168         // If session is already in closing, no need to close it again
 169         if (session != null && isSessionClosing.compareAndSet(false, true)) {
 170             session.close();
 171         }
 172     }
 173
 174     private void tearDown(final String reason) {
 175         if (!isSessionClosing()) {
 176             LOG.warn("It's curious that no one to close the session but tearDown is called!");
 177         }
 178         LOG.debug("Tearing down {}", reason);
 179         final List<UncancellableFuture<RpcResult<NetconfMessage>>> futuresToCancel = Lists.newArrayList();
 180         sessionLock.lock();
 181         try {
 182             if (session != null) {
 183                 session = null;
 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         } finally {
 203             sessionLock.unlock();
 204         }
 205
 206         // Notify pending request futures outside of the sessionLock to avoid unnecessarily
 207         // blocking the caller.
 208         for (final UncancellableFuture<RpcResult<NetconfMessage>> future : futuresToCancel) {
 209             if (Strings.isNullOrEmpty(reason)) {
 210                 future.set(createSessionDownRpcResult());
 211             } else {
 212                 future.set(createErrorRpcResult(RpcError.ErrorType.TRANSPORT, reason));
 213             }
 214         }
 215
 216         isSessionClosing.set(false);
 217     }
 218
 219     private RpcResult<NetconfMessage> createSessionDownRpcResult() {
 220         return createErrorRpcResult(RpcError.ErrorType.TRANSPORT,
 221                 String.format("The netconf session to %1$s is disconnected", id.getName()));
 222     }
 223
 224     private static RpcResult<NetconfMessage> createErrorRpcResult(final RpcError.ErrorType errorType,
 225             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 exception) {
 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, exception);
 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         } finally {
 289             sessionLock.unlock();
 290         }
 291
 292         if (request != null) {
 293
 294             LOG.debug("{}: Message received {}", id, message);
 295
 296             if (LOG.isTraceEnabled()) {
 297                 LOG.trace("{}: Matched request: {} to response: {}", id, msgToS(request.request), msgToS(message));
 298             }
 299
 300             try {
 301                 NetconfMessageTransformUtil.checkValidReply(request.request, message);
 302             } catch (final NetconfDocumentedException e) {
 303                 LOG.warn(
 304                         "{}: Invalid request-reply match,"
 305                                 + "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"
 344                     + id.getName());
 345             sessionLock.unlock();
 346             return Futures.immediateFailedFuture(new NetconfDocumentedException(
 347                     "Limit of rpc messages was reached (Limit :" + concurentRpcMsgs
 348                             + ") waiting for emptying the queue of Netconf device with id" + id.getName()));
 349         }
 350
 351         try {
 352             return sendRequestWithLock(message, rpc);
 353         } finally {
 354             sessionLock.unlock();
 355         }
 356     }
 357
 358     private ListenableFuture<RpcResult<NetconfMessage>> sendRequestWithLock(final NetconfMessage message,
 359                                                                             final QName rpc) {
 360         if (LOG.isTraceEnabled()) {
 361             LOG.trace("{}: Sending message {}", id, msgToS(message));
 362         }
 363
 364         if (session == null) {
 365             LOG.warn("{}: Session is disconnected, failing RPC request {}",
 366                     id, message);
 367             return Futures.immediateFuture(createSessionDownRpcResult());
 368         }
 369
 370         final Request req = new Request(new UncancellableFuture<>(true), message);
 371         requests.add(req);
 372
 373         session.sendMessage(req.request).addListener(future -> {
 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             } else {
 388                 LOG.trace("Finished sending request {}", req.request);
 389             }
 390         });
 391
 392         return req.future;
 393     }
 394
 395     private void processNotification(final NetconfMessage notification) {
 396         if (LOG.isTraceEnabled()) {
 397             LOG.trace("{}: Notification received: {}", id, notification);
 398         }
 399
 400         remoteDevice.onNotification(notification);
 401     }
 402
 403     private static boolean isNotification(final NetconfMessage message) {
 404         final XmlElement xmle = XmlElement.fromDomDocument(message.getDocument());
 405         return XmlNetconfConstants.NOTIFICATION_ELEMENT_NAME.equals(xmle.getName()) ;
 406     }
 407
 408     private static final class Request {
 409         final UncancellableFuture<RpcResult<NetconfMessage>> future;
 410         final NetconfMessage request;
 411
 412         private Request(final UncancellableFuture<RpcResult<NetconfMessage>> future,
 413                         final NetconfMessage request) {
 414             this.future = future;
 415             this.request = request;
 416         }
 417     }
 418 }