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.util.ArrayDeque;
  15 import java.util.ArrayList;
  16 import java.util.Iterator;
  17 import java.util.List;
  18 import java.util.Optional;
  19 import java.util.Queue;
  20 import java.util.concurrent.Semaphore;
  21 import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
  22 import java.util.concurrent.locks.Lock;
  23 import java.util.concurrent.locks.ReentrantLock;
  24 import org.opendaylight.netconf.api.FailedNetconfMessage;
  25 import org.opendaylight.netconf.api.NetconfDocumentedException;
  26 import org.opendaylight.netconf.api.NetconfMessage;
  27 import org.opendaylight.netconf.api.NetconfTerminationReason;
  28 import org.opendaylight.netconf.api.xml.XmlElement;
  29 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  30 import org.opendaylight.netconf.api.xml.XmlUtil;
  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.util.concurrent.FluentFutures;
  41 import org.opendaylight.yangtools.yang.common.QName;
  42 import org.opendaylight.yangtools.yang.common.RpcError;
  43 import org.opendaylight.yangtools.yang.common.RpcResult;
  44 import org.opendaylight.yangtools.yang.common.RpcResultBuilder;
  45 import org.slf4j.Logger;
  46 import org.slf4j.LoggerFactory;
  47
  48 public class NetconfDeviceCommunicator
  49         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 currentSession;
  63
  64     private final SettableFuture<NetconfDeviceCapabilities> firstConnectionFuture;
  65     private Future<?> initFuture;
  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 static final AtomicIntegerFieldUpdater<NetconfDeviceCommunicator> CLOSING_UPDATER =
  73             AtomicIntegerFieldUpdater.newUpdater(NetconfDeviceCommunicator.class, "closing");
  74     private volatile int closing;
  75
  76     public boolean isSessionClosing() {
  77         return closing != 0;
  78     }
  79
  80     public NetconfDeviceCommunicator(
  81             final RemoteDeviceId id,
  82             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  83             final UserPreferences netconfSessionPreferences, final int rpcMessageLimit) {
  84         this(id, remoteDevice, Optional.of(netconfSessionPreferences), rpcMessageLimit);
  85     }
  86
  87     public NetconfDeviceCommunicator(
  88             final RemoteDeviceId id,
  89             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  90             final int rpcMessageLimit) {
  91         this(id, remoteDevice, Optional.empty(), rpcMessageLimit);
  92     }
  93
  94     private NetconfDeviceCommunicator(
  95             final RemoteDeviceId id,
  96             final RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> remoteDevice,
  97             final Optional<UserPreferences> overrideNetconfCapabilities, final int rpcMessageLimit) {
  98         this.concurentRpcMsgs = rpcMessageLimit;
  99         this.id = id;
 100         this.remoteDevice = remoteDevice;
 101         this.overrideNetconfCapabilities = overrideNetconfCapabilities;
 102         this.firstConnectionFuture = SettableFuture.create();
 103         this.semaphore = rpcMessageLimit > 0 ? new Semaphore(rpcMessageLimit) : null;
 104     }
 105
 106     @Override
 107     public void onSessionUp(final NetconfClientSession session) {
 108         sessionLock.lock();
 109         try {
 110             LOG.debug("{}: Session established", id);
 111             currentSession = session;
 112
 113             NetconfSessionPreferences netconfSessionPreferences =
 114                                              NetconfSessionPreferences.fromNetconfSession(session);
 115             LOG.trace("{}: Session advertised capabilities: {}", id,
 116                     netconfSessionPreferences);
 117
 118             if (overrideNetconfCapabilities.isPresent()) {
 119                 final NetconfSessionPreferences sessionPreferences = overrideNetconfCapabilities
 120                         .get().getSessionPreferences();
 121                 netconfSessionPreferences = overrideNetconfCapabilities.get().moduleBasedCapsOverrided()
 122                         ? netconfSessionPreferences.replaceModuleCaps(sessionPreferences)
 123                         : netconfSessionPreferences.addModuleCaps(sessionPreferences);
 124
 125                 netconfSessionPreferences = overrideNetconfCapabilities.get().nonModuleBasedCapsOverrided()
 126                         ? netconfSessionPreferences.replaceNonModuleCaps(sessionPreferences)
 127                         : netconfSessionPreferences.addNonModuleCaps(sessionPreferences);
 128                 LOG.debug("{}: Session capabilities overridden, capabilities that will be used: {}", id,
 129                         netconfSessionPreferences);
 130             }
 131
 132             remoteDevice.onRemoteSessionUp(netconfSessionPreferences, this);
 133             if (!firstConnectionFuture.isDone()) {
 134                 firstConnectionFuture.set(netconfSessionPreferences.getNetconfDeviceCapabilities());
 135             }
 136         } finally {
 137             sessionLock.unlock();
 138         }
 139     }
 140
 141     /**
 142      * Initialize remote connection.
 143      *
 144      * @param dispatcher {@code NetconfCLientDispatcher}
 145      * @param config     {@code NetconfClientConfiguration}
 146      * @return future that returns succes on first succesfull connection and failure when the underlying
 147      *     reconnecting strategy runs out of reconnection attempts
 148      */
 149     public ListenableFuture<NetconfDeviceCapabilities> initializeRemoteConnection(
 150             final NetconfClientDispatcher dispatcher, final NetconfClientConfiguration config) {
 151         if (config instanceof NetconfReconnectingClientConfiguration) {
 152             initFuture = dispatcher.createReconnectingClient((NetconfReconnectingClientConfiguration) config);
 153         } else {
 154             initFuture = dispatcher.createClient(config);
 155         }
 156
 157
 158         initFuture.addListener(future -> {
 159             if (!future.isSuccess() && !future.isCancelled()) {
 160                 LOG.debug("{}: Connection failed", id, future.cause());
 161                 NetconfDeviceCommunicator.this.remoteDevice.onRemoteSessionFailed(future.cause());
 162                 if (firstConnectionFuture.isDone()) {
 163                     firstConnectionFuture.setException(future.cause());
 164                 }
 165             }
 166         });
 167         return firstConnectionFuture;
 168     }
 169
 170     public void disconnect() {
 171         // If session is already in closing, no need to close it again
 172         if (currentSession != null && startClosing() && currentSession.isUp()) {
 173             currentSession.close();
 174         }
 175     }
 176
 177     private void tearDown(final String reason) {
 178         if (!isSessionClosing()) {
 179             LOG.warn("It's curious that no one to close the session but tearDown is called!");
 180         }
 181         LOG.debug("Tearing down {}", reason);
 182         final List<UncancellableFuture<RpcResult<NetconfMessage>>> futuresToCancel = new ArrayList<>();
 183         sessionLock.lock();
 184         try {
 185             if (currentSession != null) {
 186                 currentSession = null;
 187                 /*
 188                  * Walk all requests, check if they have been executing
 189                  * or cancelled and remove them from the queue.
 190                  */
 191                 final Iterator<Request> it = requests.iterator();
 192                 while (it.hasNext()) {
 193                     final Request r = it.next();
 194                     if (r.future.isUncancellable()) {
 195                         futuresToCancel.add(r.future);
 196                         it.remove();
 197                     } else if (r.future.isCancelled()) {
 198                         // This just does some house-cleaning
 199                         it.remove();
 200                     }
 201                 }
 202
 203                 remoteDevice.onRemoteSessionDown();
 204             }
 205         } finally {
 206             sessionLock.unlock();
 207         }
 208
 209         // Notify pending request futures outside of the sessionLock to avoid unnecessarily
 210         // blocking the caller.
 211         for (final UncancellableFuture<RpcResult<NetconfMessage>> future : futuresToCancel) {
 212             if (Strings.isNullOrEmpty(reason)) {
 213                 future.set(createSessionDownRpcResult());
 214             } else {
 215                 future.set(createErrorRpcResult(RpcError.ErrorType.TRANSPORT, reason));
 216             }
 217         }
 218
 219         closing = 0;
 220     }
 221
 222     private RpcResult<NetconfMessage> createSessionDownRpcResult() {
 223         return createErrorRpcResult(RpcError.ErrorType.TRANSPORT,
 224                 String.format("The netconf session to %1$s is disconnected", id.getName()));
 225     }
 226
 227     private static RpcResult<NetconfMessage> createErrorRpcResult(final RpcError.ErrorType errorType,
 228             final String message) {
 229         return RpcResultBuilder.<NetconfMessage>failed()
 230             .withError(errorType, NetconfDocumentedException.ErrorTag.OPERATION_FAILED.getTagValue(), message).build();
 231     }
 232
 233     @Override
 234     public void onSessionDown(final NetconfClientSession session, final Exception exception) {
 235         // If session is already in closing, no need to call tearDown again.
 236         if (startClosing()) {
 237             LOG.warn("{}: Session went down", id, exception);
 238             tearDown(null);
 239         }
 240     }
 241
 242     @Override
 243     public void onSessionTerminated(final NetconfClientSession session, final NetconfTerminationReason reason) {
 244         // onSessionTerminated is called directly by disconnect, no need to compare and set isSessionClosing.
 245         LOG.warn("{}: Session terminated {}", id, reason);
 246         tearDown(reason.getErrorMessage());
 247     }
 248
 249     @Override
 250     public void close() {
 251         // Cancel reconnect if in progress
 252         if (initFuture != null) {
 253             initFuture.cancel(false);
 254         }
 255         // Disconnect from device
 256         // tear down not necessary, called indirectly by the close in disconnect()
 257         disconnect();
 258     }
 259
 260     @Override
 261     public void onMessage(final NetconfClientSession session, final NetconfMessage message) {
 262         /*
 263          * Dispatch between notifications and messages. Messages need to be processed
 264          * with lock held, notifications do not.
 265          */
 266         if (isNotification(message)) {
 267             processNotification(message);
 268         } else {
 269             processMessage(message);
 270         }
 271     }
 272
 273     private void processMessage(final NetconfMessage message) {
 274         Request request = null;
 275         sessionLock.lock();
 276
 277         try {
 278             request = requests.peek();
 279             if (request != null && request.future.isUncancellable()) {
 280                 request = requests.poll();
 281                 // we have just removed one request from the queue
 282                 // we can also release one permit
 283                 if (semaphore != null) {
 284                     semaphore.release();
 285                 }
 286             } else {
 287                 request = null;
 288                 LOG.warn("{}: Ignoring unsolicited message {}", id,
 289                         msgToS(message));
 290             }
 291         } finally {
 292             sessionLock.unlock();
 293         }
 294
 295         if (request != null) {
 296
 297             if (FailedNetconfMessage.class.isInstance(message)) {
 298                 request.future.set(NetconfMessageTransformUtil.toRpcResult((FailedNetconfMessage) message));
 299                 return;
 300             }
 301
 302             LOG.debug("{}: Message received {}", id, message);
 303
 304             if (LOG.isTraceEnabled()) {
 305                 LOG.trace("{}: Matched request: {} to response: {}", id, msgToS(request.request), msgToS(message));
 306             }
 307
 308             try {
 309                 NetconfMessageTransformUtil.checkValidReply(request.request, message);
 310             } catch (final NetconfDocumentedException e) {
 311                 LOG.warn(
 312                         "{}: Invalid request-reply match,"
 313                                 + "reply message contains different message-id, request: {}, response: {}",
 314                         id, msgToS(request.request), msgToS(message), e);
 315
 316                 request.future.set(RpcResultBuilder.<NetconfMessage>failed()
 317                         .withRpcError(NetconfMessageTransformUtil.toRpcError(e)).build());
 318
 319                 //recursively processing message to eventually find matching request
 320                 processMessage(message);
 321
 322                 return;
 323             }
 324
 325             try {
 326                 NetconfMessageTransformUtil.checkSuccessReply(message);
 327             } catch (final NetconfDocumentedException e) {
 328                 LOG.warn(
 329                         "{}: Error reply from remote device, request: {}, response: {}",
 330                         id, msgToS(request.request), msgToS(message), e);
 331
 332                 request.future.set(RpcResultBuilder.<NetconfMessage>failed()
 333                         .withRpcError(NetconfMessageTransformUtil.toRpcError(e)).build());
 334                 return;
 335             }
 336
 337             request.future.set(RpcResultBuilder.success(message).build());
 338         }
 339     }
 340
 341     private static String msgToS(final NetconfMessage msg) {
 342         return XmlUtil.toString(msg.getDocument());
 343     }
 344
 345     @Override
 346     public ListenableFuture<RpcResult<NetconfMessage>> sendRequest(final NetconfMessage message, final QName rpc) {
 347         sessionLock.lock();
 348         try {
 349             if (semaphore != null && !semaphore.tryAcquire()) {
 350                 LOG.warn("Limit of concurrent rpc messages was reached (limit: {}). Rpc reply message is needed. "
 351                     + "Discarding request of Netconf device with id {}", concurentRpcMsgs, id.getName());
 352                 return FluentFutures.immediateFailedFluentFuture(new NetconfDocumentedException(
 353                         "Limit of rpc messages was reached (Limit :" + concurentRpcMsgs
 354                         + ") waiting for emptying the queue of Netconf device with id" + id.getName()));
 355             }
 356
 357             return sendRequestWithLock(message, rpc);
 358         } finally {
 359             sessionLock.unlock();
 360         }
 361     }
 362
 363     private ListenableFuture<RpcResult<NetconfMessage>> sendRequestWithLock(final NetconfMessage message,
 364                                                                             final QName rpc) {
 365         if (LOG.isTraceEnabled()) {
 366             LOG.trace("{}: Sending message {}", id, msgToS(message));
 367         }
 368
 369         if (currentSession == null) {
 370             LOG.warn("{}: Session is disconnected, failing RPC request {}",
 371                     id, message);
 372             return FluentFutures.immediateFluentFuture(createSessionDownRpcResult());
 373         }
 374
 375         final Request req = new Request(new UncancellableFuture<>(true), message);
 376         requests.add(req);
 377
 378         currentSession.sendMessage(req.request).addListener(future -> {
 379             if (!future.isSuccess()) {
 380                 // We expect that a session down will occur at this point
 381                 LOG.debug("{}: Failed to send request {}", id,
 382                         XmlUtil.toString(req.request.getDocument()),
 383                         future.cause());
 384
 385                 if (future.cause() != null) {
 386                     req.future.set(createErrorRpcResult(RpcError.ErrorType.TRANSPORT,
 387                             future.cause().getLocalizedMessage()));
 388                 } else {
 389                     req.future.set(createSessionDownRpcResult()); // assume session is down
 390                 }
 391                 req.future.setException(future.cause());
 392             } else {
 393                 LOG.trace("Finished sending request {}", req.request);
 394             }
 395         });
 396
 397         return req.future;
 398     }
 399
 400     private void processNotification(final NetconfMessage notification) {
 401         if (LOG.isTraceEnabled()) {
 402             LOG.trace("{}: Notification received: {}", id, notification);
 403         }
 404
 405         remoteDevice.onNotification(notification);
 406     }
 407
 408     private static boolean isNotification(final NetconfMessage message) {
 409         if (message.getDocument() == null) {
 410             // We have no message, which mean we have a FailedNetconfMessage
 411             return false;
 412         }
 413         final XmlElement xmle = XmlElement.fromDomDocument(message.getDocument());
 414         return XmlNetconfConstants.NOTIFICATION_ELEMENT_NAME.equals(xmle.getName()) ;
 415     }
 416
 417     private static final class Request {
 418         final UncancellableFuture<RpcResult<NetconfMessage>> future;
 419         final NetconfMessage request;
 420
 421         private Request(final UncancellableFuture<RpcResult<NetconfMessage>> future,
 422                         final NetconfMessage request) {
 423             this.future = future;
 424             this.request = request;
 425         }
 426     }
 427
 428     private boolean startClosing() {
 429         return CLOSING_UPDATER.compareAndSet(this, 0, 1);
 430     }
 431 }