opendaylight/md-sal/sal-netconf-connector/src/main/java/org/opendaylight/controller/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.controller.sal.connect.netconf.listener;
   9
  10 import java.util.ArrayDeque;
  11 import java.util.Collections;
  12 import java.util.Iterator;
  13 import java.util.List;
  14 import java.util.Queue;
  15 import java.util.concurrent.locks.Lock;
  16 import java.util.concurrent.locks.ReentrantLock;
  17
  18 import org.opendaylight.controller.netconf.api.NetconfDocumentedException;
  19 import org.opendaylight.controller.netconf.api.NetconfMessage;
  20 import org.opendaylight.controller.netconf.api.NetconfTerminationReason;
  21 import org.opendaylight.controller.netconf.api.xml.XmlNetconfConstants;
  22 import org.opendaylight.controller.netconf.client.NetconfClientDispatcher;
  23 import org.opendaylight.controller.netconf.client.NetconfClientSession;
  24 import org.opendaylight.controller.netconf.client.NetconfClientSessionListener;
  25 import org.opendaylight.controller.netconf.client.conf.NetconfReconnectingClientConfiguration;
  26 import org.opendaylight.controller.netconf.util.xml.XmlElement;
  27 import org.opendaylight.controller.netconf.util.xml.XmlUtil;
  28 import org.opendaylight.controller.sal.common.util.RpcErrors;
  29 import org.opendaylight.controller.sal.common.util.Rpcs;
  30 import org.opendaylight.controller.sal.connect.api.RemoteDevice;
  31 import org.opendaylight.controller.sal.connect.api.RemoteDeviceCommunicator;
  32 import org.opendaylight.controller.sal.connect.netconf.util.NetconfMessageTransformUtil;
  33 import org.opendaylight.controller.sal.connect.util.FailedRpcResult;
  34 import org.opendaylight.controller.sal.connect.util.RemoteDeviceId;
  35 import org.opendaylight.yangtools.yang.common.QName;
  36 import org.opendaylight.yangtools.yang.common.RpcError;
  37 import org.opendaylight.yangtools.yang.common.RpcResult;
  38 import org.slf4j.Logger;
  39 import org.slf4j.LoggerFactory;
  40
  41 import com.google.common.base.Strings;
  42 import com.google.common.collect.Lists;
  43 import com.google.common.util.concurrent.Futures;
  44 import com.google.common.util.concurrent.ListenableFuture;
  45
  46 import io.netty.util.concurrent.Future;
  47 import io.netty.util.concurrent.FutureListener;
  48
  49 public class NetconfDeviceCommunicator implements NetconfClientSessionListener, RemoteDeviceCommunicator<NetconfMessage> {
  50
  51     private static final Logger logger = LoggerFactory.getLogger(NetconfDeviceCommunicator.class);
  52
  53     private final RemoteDevice<NetconfSessionCapabilities, NetconfMessage> remoteDevice;
  54     private final RemoteDeviceId id;
  55     private final Lock sessionLock = new ReentrantLock();
  56
  57     public NetconfDeviceCommunicator(final RemoteDeviceId id,
  58             final RemoteDevice<NetconfSessionCapabilities, NetconfMessage> remoteDevice) {
  59         this.id = id;
  60         this.remoteDevice = remoteDevice;
  61     }
  62
  63     private final Queue<Request> requests = new ArrayDeque<>();
  64     private NetconfClientSession session;
  65
  66     @Override
  67     public void onSessionUp(final NetconfClientSession session) {
  68         sessionLock.lock();
  69         try {
  70             logger.debug("{}: Session established", id);
  71             this.session = session;
  72
  73             final NetconfSessionCapabilities netconfSessionCapabilities =
  74                                              NetconfSessionCapabilities.fromNetconfSession(session);
  75             logger.trace("{}: Session advertised capabilities: {}", id, netconfSessionCapabilities);
  76
  77             remoteDevice.onRemoteSessionUp(netconfSessionCapabilities, this);
  78         }
  79         finally {
  80             sessionLock.unlock();
  81         }
  82     }
  83
  84     public void initializeRemoteConnection(final NetconfClientDispatcher dispatch,
  85                                            final NetconfReconnectingClientConfiguration config) {
  86         dispatch.createReconnectingClient(config);
  87     }
  88
  89     private void tearDown( String reason ) {
  90         List<UncancellableFuture<RpcResult<NetconfMessage>>> futuresToCancel = Lists.newArrayList();
  91         sessionLock.lock();
  92         try {
  93             if( session != null ) {
  94                 session = null;
  95
  96                 /*
  97                  * Walk all requests, check if they have been executing
  98                  * or cancelled and remove them from the queue.
  99                  */
 100                 final Iterator<Request> it = requests.iterator();
 101                 while (it.hasNext()) {
 102                     final Request r = it.next();
 103                     if (r.future.isUncancellable()) {
 104                         futuresToCancel.add( r.future );
 105                         it.remove();
 106                     } else if (r.future.isCancelled()) {
 107                         // This just does some house-cleaning
 108                         it.remove();
 109                     }
 110                 }
 111
 112                 remoteDevice.onRemoteSessionDown();
 113             }
 114         }
 115         finally {
 116             sessionLock.unlock();
 117         }
 118
 119         // Notify pending request futures outside of the sessionLock to avoid unnecessarily
 120         // blocking the caller.
 121         for( UncancellableFuture<RpcResult<NetconfMessage>> future: futuresToCancel ) {
 122             if( Strings.isNullOrEmpty( reason ) ) {
 123                 future.set( createSessionDownRpcResult() );
 124             } else {
 125                 future.set( createErrorRpcResult( RpcError.ErrorType.TRANSPORT, reason ) );
 126             }
 127         }
 128     }
 129
 130     private RpcResult<NetconfMessage> createSessionDownRpcResult()
 131     {
 132         return createErrorRpcResult( RpcError.ErrorType.TRANSPORT,
 133                              String.format( "The netconf session to %1$s is disconnected", id.getName() ) );
 134     }
 135
 136     private RpcResult<NetconfMessage> createErrorRpcResult( RpcError.ErrorType errorType, String message )
 137     {
 138         return new FailedRpcResult<NetconfMessage>( RpcErrors.getRpcError( null,
 139                 NetconfDocumentedException.ErrorTag.operation_failed.getTagValue(),
 140                 null, RpcError.ErrorSeverity.ERROR, message, errorType, null ) );
 141     }
 142
 143     @Override
 144     public void onSessionDown(final NetconfClientSession session, final Exception e) {
 145         logger.warn("{}: Session went down", id, e);
 146         tearDown( null );
 147     }
 148
 149     @Override
 150     public void onSessionTerminated(final NetconfClientSession session, final NetconfTerminationReason reason) {
 151         logger.warn("{}: Session terminated {}", id, reason);
 152         tearDown( reason.getErrorMessage() );
 153     }
 154
 155     @Override
 156     public void close() {
 157         tearDown( String.format( "The netconf session to %1$s has been closed", id.getName() ) );
 158     }
 159
 160     @Override
 161     public void onMessage(final NetconfClientSession session, final NetconfMessage message) {
 162         /*
 163          * Dispatch between notifications and messages. Messages need to be processed
 164          * with lock held, notifications do not.
 165          */
 166         if (isNotification(message)) {
 167             processNotification(message);
 168         } else {
 169             processMessage(message);
 170         }
 171     }
 172
 173     private void processMessage(final NetconfMessage message) {
 174         Request request = null;
 175         sessionLock.lock();
 176         try {
 177             request = requests.peek();
 178             if (request.future.isUncancellable()) {
 179                 requests.poll();
 180             }
 181             else {
 182                 request = null;
 183                 logger.warn("{}: Ignoring unsolicited message {}", id, msgToS(message));
 184             }
 185         }
 186         finally {
 187             sessionLock.unlock();
 188         }
 189
 190         if( request != null ) {
 191
 192             logger.debug("{}: Message received {}", id, message);
 193
 194             if(logger.isTraceEnabled()) {
 195                 logger.trace( "{}: Matched request: {} to response: {}", id,
 196                               msgToS( request.request ), msgToS( message ) );
 197             }
 198
 199             try {
 200                 NetconfMessageTransformUtil.checkValidReply( request.request, message );
 201             }
 202             catch (final NetconfDocumentedException e) {
 203                 logger.warn( "{}: Invalid request-reply match, reply message contains different message-id, request: {}, response: {}",
 204                              id, msgToS( request.request ), msgToS( message ), e );
 205
 206                 request.future.set( new FailedRpcResult<NetconfMessage>(
 207                                                            NetconfMessageTransformUtil.toRpcError( e ) ) );
 208                 return;
 209             }
 210
 211             try {
 212                 NetconfMessageTransformUtil.checkSuccessReply(message);
 213             }
 214             catch( NetconfDocumentedException e ) {
 215                 logger.warn( "{}: Error reply from remote device, request: {}, response: {}", id,
 216                              msgToS( request.request ), msgToS( message ), e );
 217
 218                 request.future.set( new FailedRpcResult<NetconfMessage>(
 219                                                           NetconfMessageTransformUtil.toRpcError( e ) ) );
 220                 return;
 221             }
 222
 223             request.future.set(Rpcs.getRpcResult( true, message, Collections.<RpcError>emptySet() ) );
 224         }
 225     }
 226
 227     private static String msgToS(final NetconfMessage msg) {
 228         return XmlUtil.toString(msg.getDocument());
 229     }
 230
 231     @Override
 232     public ListenableFuture<RpcResult<NetconfMessage>> sendRequest(
 233                                                final NetconfMessage message, final QName rpc) {
 234         sessionLock.lock();
 235         try {
 236             return sendRequestWithLock( message, rpc );
 237         }
 238         finally {
 239             sessionLock.unlock();
 240         }
 241     }
 242
 243     private ListenableFuture<RpcResult<NetconfMessage>> sendRequestWithLock(
 244                                                final NetconfMessage message, final QName rpc) {
 245         if(logger.isTraceEnabled()) {
 246             logger.trace("{}: Sending message {}", id, msgToS(message));
 247         }
 248
 249         if (session == null) {
 250             logger.warn("{}: Session is disconnected, failing RPC request {}", id, message);
 251             return Futures.immediateFuture( createSessionDownRpcResult() );
 252         }
 253
 254         final Request req = new Request( new UncancellableFuture<RpcResult<NetconfMessage>>(true),
 255                                          message );
 256         requests.add(req);
 257
 258         session.sendMessage(req.request).addListener(new FutureListener<Void>() {
 259             @Override
 260             public void operationComplete(final Future<Void> future) throws Exception {
 261                 if( !future.isSuccess() ) {
 262                     // We expect that a session down will occur at this point
 263                     logger.debug( "{}: Failed to send request {}", id,
 264                                   XmlUtil.toString(req.request.getDocument()), future.cause() );
 265
 266                     if( future.cause() != null ) {
 267                         req.future.set( createErrorRpcResult( RpcError.ErrorType.TRANSPORT,
 268                                                               future.cause().getLocalizedMessage() ) );
 269                     } else {
 270                         req.future.set( createSessionDownRpcResult() ); // assume session is down
 271                     }
 272                     req.future.setException( future.cause() );
 273                 }
 274                 else {
 275                     logger.trace( "Finished sending request {}", req.request );
 276                 }
 277             }
 278         });
 279
 280         return req.future;
 281     }
 282
 283     private void processNotification(final NetconfMessage notification) {
 284         logger.debug("{}: Notification received: {}", id, notification);
 285
 286         if(logger.isTraceEnabled()) {
 287             logger.trace("{}: Notification received: {}", id, msgToS(notification));
 288         }
 289
 290         remoteDevice.onNotification(notification);
 291     }
 292
 293     private static boolean isNotification(final NetconfMessage message) {
 294         final XmlElement xmle = XmlElement.fromDomDocument(message.getDocument());
 295         return XmlNetconfConstants.NOTIFICATION_ELEMENT_NAME.equals(xmle.getName()) ;
 296     }
 297
 298     private static final class Request {
 299         final UncancellableFuture<RpcResult<NetconfMessage>> future;
 300         final NetconfMessage request;
 301
 302         private Request(final UncancellableFuture<RpcResult<NetconfMessage>> future,
 303                         final NetconfMessage request) {
 304             this.future = future;
 305             this.request = request;
 306         }
 307     }
 308 }