plugins/netconf-client-mdsal/src/main/java/org/opendaylight/netconf/client/mdsal/spi/KeepaliveSalFacade.java

   1 /*
   2  * Copyright (c) 2015 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.client.mdsal.spi;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11 import static java.util.Objects.requireNonNull;
  12 import static org.opendaylight.netconf.client.mdsal.impl.NetconfBaseOps.getSourceNode;
  13 import static org.opendaylight.netconf.client.mdsal.impl.NetconfMessageTransformUtil.NETCONF_GET_CONFIG_NODEID;
  14 import static org.opendaylight.netconf.client.mdsal.impl.NetconfMessageTransformUtil.NETCONF_RUNNING_NODEID;
  15
  16 import com.google.common.util.concurrent.FutureCallback;
  17 import com.google.common.util.concurrent.Futures;
  18 import com.google.common.util.concurrent.ListenableFuture;
  19 import com.google.common.util.concurrent.MoreExecutors;
  20 import com.google.common.util.concurrent.SettableFuture;
  21 import io.netty.util.Timeout;
  22 import io.netty.util.TimerTask;
  23 import java.util.concurrent.CancellationException;
  24 import java.util.concurrent.TimeUnit;
  25 import javax.xml.transform.dom.DOMSource;
  26 import org.checkerframework.checker.lock.qual.GuardedBy;
  27 import org.eclipse.jdt.annotation.NonNull;
  28 import org.opendaylight.mdsal.dom.api.DOMNotification;
  29 import org.opendaylight.mdsal.dom.api.DOMRpcAvailabilityListener;
  30 import org.opendaylight.mdsal.dom.api.DOMRpcResult;
  31 import org.opendaylight.mdsal.dom.api.DOMRpcService;
  32 import org.opendaylight.netconf.client.mdsal.NetconfDeviceCommunicator;
  33 import org.opendaylight.netconf.client.mdsal.NetconfDeviceSchema;
  34 import org.opendaylight.netconf.client.mdsal.api.NetconfSessionPreferences;
  35 import org.opendaylight.netconf.client.mdsal.api.RemoteDeviceHandler;
  36 import org.opendaylight.netconf.client.mdsal.api.RemoteDeviceId;
  37 import org.opendaylight.netconf.client.mdsal.api.RemoteDeviceServices;
  38 import org.opendaylight.netconf.client.mdsal.api.RemoteDeviceServices.Rpcs;
  39 import org.opendaylight.netconf.client.mdsal.api.SchemalessRpcService;
  40 import org.opendaylight.netconf.client.mdsal.impl.NetconfMessageTransformUtil;
  41 import org.opendaylight.netconf.common.NetconfTimer;
  42 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.base._1._0.rev110601.GetConfig;
  43 import org.opendaylight.yangtools.concepts.Registration;
  44 import org.opendaylight.yangtools.yang.common.QName;
  45 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  46 import org.slf4j.Logger;
  47 import org.slf4j.LoggerFactory;
  48
  49 /**
  50  * SalFacade proxy that invokes keepalive RPCs to prevent session shutdown from remote device
  51  * and to detect incorrect session drops (netconf session is inactive, but TCP/SSH connection is still present).
  52  * The keepalive RPC is a get-config with empty filter.
  53  */
  54 public final class KeepaliveSalFacade implements RemoteDeviceHandler {
  55     private static final Logger LOG = LoggerFactory.getLogger(KeepaliveSalFacade.class);
  56
  57     // 2 minutes keepalive delay by default
  58     private static final long DEFAULT_DELAY = TimeUnit.MINUTES.toSeconds(2);
  59
  60     // 1 minute transaction timeout by default
  61     private static final long DEFAULT_TRANSACTION_TIMEOUT_MILLI = TimeUnit.MILLISECONDS.toMillis(60000);
  62
  63     private final RemoteDeviceHandler deviceHandler;
  64     private final RemoteDeviceId deviceId;
  65     private final NetconfTimer timer;
  66     private final long keepaliveDelaySeconds;
  67     private final long timeoutNanos;
  68     private final long delayNanos;
  69
  70     private volatile NetconfDeviceCommunicator listener;
  71     private volatile KeepaliveTask task;
  72
  73     public KeepaliveSalFacade(final RemoteDeviceId deviceId, final RemoteDeviceHandler deviceHandler,
  74             final NetconfTimer timer, final long keepaliveDelaySeconds, final long requestTimeoutMillis) {
  75         this.deviceId = requireNonNull(deviceId);
  76         this.deviceHandler = requireNonNull(deviceHandler);
  77         this.timer = requireNonNull(timer);
  78         this.keepaliveDelaySeconds = keepaliveDelaySeconds;
  79         delayNanos = TimeUnit.SECONDS.toNanos(keepaliveDelaySeconds);
  80         timeoutNanos = TimeUnit.MILLISECONDS.toNanos(requestTimeoutMillis);
  81     }
  82
  83     public KeepaliveSalFacade(final RemoteDeviceId deviceId, final RemoteDeviceHandler deviceHandler,
  84             final NetconfTimer timer) {
  85         this(deviceId, deviceHandler, timer, DEFAULT_DELAY, DEFAULT_TRANSACTION_TIMEOUT_MILLI);
  86     }
  87
  88     /**
  89      * Set the netconf session listener whenever ready.
  90      *
  91      * @param listener netconf session listener
  92      */
  93     public void setListener(final NetconfDeviceCommunicator listener) {
  94         this.listener = listener;
  95     }
  96
  97     /**
  98      * Cancel current keepalive and free it.
  99      */
 100     private synchronized void stopKeepalives() {
 101         final var localTask = task;
 102         if (localTask != null) {
 103             localTask.disableKeepalive();
 104             task = null;
 105         }
 106     }
 107
 108     private void disableKeepalive() {
 109         final var localTask = task;
 110         if (localTask != null) {
 111             localTask.disableKeepalive();
 112         }
 113     }
 114
 115     private void enableKeepalive() {
 116         final var localTask = task;
 117         if (localTask != null) {
 118             localTask.enableKeepalive();
 119         }
 120     }
 121
 122     private void disconnect() {
 123         checkState(listener != null, "%s: Unable to reconnect, session listener is missing", deviceId);
 124         stopKeepalives();
 125         LOG.info("{}: Reconnecting inactive netconf session", deviceId);
 126         listener.disconnect();
 127     }
 128
 129     @Override
 130     public void onDeviceConnected(final NetconfDeviceSchema deviceSchema,
 131             final NetconfSessionPreferences sessionPreferences, final RemoteDeviceServices services) {
 132         final var devRpc = services.rpcs();
 133         task = new KeepaliveTask(devRpc);
 134
 135         final Rpcs keepaliveRpcs;
 136         if (devRpc instanceof Rpcs.Normalized normalized) {
 137             keepaliveRpcs = new NormalizedKeepaliveRpcs(normalized);
 138         } else if (devRpc instanceof Rpcs.Schemaless schemaless) {
 139             keepaliveRpcs = new SchemalessKeepaliveRpcs(schemaless);
 140         } else {
 141             throw new IllegalStateException("Unhandled " + devRpc);
 142         }
 143
 144         deviceHandler.onDeviceConnected(deviceSchema, sessionPreferences, new RemoteDeviceServices(keepaliveRpcs,
 145             // FIXME: wrap with keepalive
 146             services.actions()));
 147
 148         // We have performed a callback, which might have termined keepalives
 149         final var localTask = task;
 150         if (localTask != null) {
 151             LOG.debug("{}: Netconf session initiated, starting keepalives", deviceId);
 152             LOG.trace("{}: Scheduling keepalives every {}s", deviceId, keepaliveDelaySeconds);
 153             localTask.enableKeepalive();
 154         }
 155     }
 156
 157     @Override
 158     public void onDeviceDisconnected() {
 159         stopKeepalives();
 160         deviceHandler.onDeviceDisconnected();
 161     }
 162
 163     @Override
 164     public void onDeviceFailed(final Throwable throwable) {
 165         stopKeepalives();
 166         deviceHandler.onDeviceFailed(throwable);
 167     }
 168
 169     @Override
 170     public void onNotification(final DOMNotification domNotification) {
 171         final var localTask = task;
 172         if (localTask != null) {
 173             localTask.recordActivity();
 174         }
 175         deviceHandler.onNotification(domNotification);
 176     }
 177
 178     @Override
 179     public void close() {
 180         stopKeepalives();
 181         deviceHandler.close();
 182     }
 183
 184     private <T> @NonNull ListenableFuture<T> scheduleTimeout(final ListenableFuture<T> invokeFuture) {
 185         final var timeout = new RequestTimeoutTask<>(invokeFuture);
 186         scheduleTimeout(invokeFuture, timeout);
 187         return timeout.userFuture;
 188     }
 189
 190     private void scheduleTimeout(final ListenableFuture<?> future, final TimeoutTask timeoutTask) {
 191         final var timeout = timer.newTimeout(timeoutTask, timeoutNanos, TimeUnit.NANOSECONDS);
 192         future.addListener(() -> timeout.cancel(), MoreExecutors.directExecutor());
 193     }
 194
 195     /**
 196      * Invoke keepalive RPC and check the response. In case of any received response the keepalive
 197      * is considered successful and schedules next keepalive with a fixed delay. If the response is unsuccessful (no
 198      * response received, or the rcp could not even be sent) immediate reconnect is triggered as netconf session
 199      * is considered inactive/failed.
 200      */
 201     private final class KeepaliveTask implements TimerTask, FutureCallback<DOMRpcResult> {
 202         // Keepalive RPC static resources
 203         static final @NonNull ContainerNode KEEPALIVE_PAYLOAD = NetconfMessageTransformUtil.wrap(
 204             NETCONF_GET_CONFIG_NODEID, getSourceNode(NETCONF_RUNNING_NODEID), NetconfMessageTransformUtil.EMPTY_FILTER);
 205
 206         private final Rpcs devRpc;
 207
 208         @GuardedBy("this")
 209         private boolean suppressed = false;
 210
 211         private volatile long lastActivity;
 212
 213         KeepaliveTask(final Rpcs devRpc) {
 214             this.devRpc = requireNonNull(devRpc);
 215         }
 216
 217         @Override
 218         public void run(final Timeout timeout) {
 219             final long local = lastActivity;
 220             final long now = System.nanoTime();
 221             final long inFutureNanos = local + delayNanos - now;
 222             if (inFutureNanos > 0) {
 223                 reschedule(inFutureNanos);
 224             } else {
 225                 sendKeepalive(now);
 226             }
 227         }
 228
 229         void recordActivity() {
 230             lastActivity = System.nanoTime();
 231         }
 232
 233         synchronized void disableKeepalive() {
 234             // unsuppressed -> suppressed
 235             suppressed = true;
 236         }
 237
 238         synchronized void enableKeepalive() {
 239             recordActivity();
 240             if (suppressed) {
 241                 // suppressed -> unsuppressed
 242                 suppressed = false;
 243             } else {
 244                 // unscheduled -> unsuppressed
 245                 reschedule();
 246             }
 247         }
 248
 249         private synchronized void sendKeepalive(final long now) {
 250             if (suppressed) {
 251                 LOG.debug("{}: Skipping keepalive while disabled", deviceId);
 252                 // suppressed -> unscheduled
 253                 suppressed = false;
 254                 return;
 255             }
 256
 257             LOG.trace("{}: Invoking keepalive RPC", deviceId);
 258             final var deviceFuture = devRpc.invokeNetconf(GetConfig.QNAME, KEEPALIVE_PAYLOAD);
 259             lastActivity = now;
 260
 261             scheduleTimeout(deviceFuture, new TimeoutTask(deviceFuture));
 262             Futures.addCallback(deviceFuture, this, MoreExecutors.directExecutor());
 263         }
 264
 265         @Override
 266         public void onSuccess(final DOMRpcResult result) {
 267             // No matter what response we got, rpc-reply or rpc-error,
 268             // we got it from device so the netconf session is OK
 269             if (result == null) {
 270                 LOG.warn("{} Keepalive RPC returned null with response. Reconnecting netconf session", deviceId);
 271                 disconnect();
 272                 return;
 273             }
 274
 275             if (result.value() != null) {
 276                 reschedule();
 277             } else {
 278                 final var errors = result.errors();
 279                 if (!errors.isEmpty()) {
 280                     LOG.warn("{}: Keepalive RPC failed with error: {}", deviceId, errors);
 281                     reschedule();
 282                 } else {
 283                     LOG.warn("{} Keepalive RPC returned null with response. Reconnecting netconf session", deviceId);
 284                     disconnect();
 285                 }
 286             }
 287         }
 288
 289         @Override
 290         public void onFailure(final Throwable throwable) {
 291             if (throwable instanceof CancellationException) {
 292                 LOG.warn("{}: Keepalive RPC timed out. Reconnecting netconf session.", deviceId);
 293             } else {
 294                 LOG.warn("{}: Keepalive RPC failed. Reconnecting netconf session.", deviceId, throwable);
 295             }
 296             disconnect();
 297         }
 298
 299         private void reschedule() {
 300             reschedule(delayNanos);
 301         }
 302
 303         private void reschedule(final long delay) {
 304             timer.newTimeout(this, delay, TimeUnit.NANOSECONDS);
 305         }
 306     }
 307
 308     private static class TimeoutTask implements TimerTask {
 309         private final ListenableFuture<?> future;
 310
 311         TimeoutTask(final ListenableFuture<?> future) {
 312             this.future = requireNonNull(future);
 313         }
 314
 315         @Override
 316         public final void run(final Timeout timeout) {
 317             future.cancel(true);
 318         }
 319     }
 320
 321     /*
 322      * Request timeout task is called once the requestTimeoutMillis is reached. At that moment, if the request is not
 323      * yet finished, we cancel it.
 324      */
 325     private final class RequestTimeoutTask<V> extends TimeoutTask implements FutureCallback<V> {
 326         private final @NonNull SettableFuture<V> userFuture = SettableFuture.create();
 327
 328         RequestTimeoutTask(final ListenableFuture<V> rpcResultFuture) {
 329             super(rpcResultFuture);
 330             // Note: this will also wire run() to onFailure()
 331             Futures.addCallback(rpcResultFuture, this, MoreExecutors.directExecutor());
 332         }
 333
 334         @Override
 335         public void onSuccess(final V result) {
 336             // No matter what response we got,
 337             // rpc-reply or rpc-error, we got it from device so the netconf session is OK.
 338             userFuture.set(result);
 339             enableKeepalive();
 340         }
 341
 342         @Override
 343         public void onFailure(final Throwable throwable) {
 344             // User/Application RPC failed (The RPC did not reach the remote device or it has timeed out)
 345             if (throwable instanceof CancellationException) {
 346                 LOG.warn("{}: RPC timed out. Reconnecting netconf session", deviceId);
 347             } else {
 348                 LOG.warn("{}: RPC failed. Reconnecting netconf session", deviceId, throwable);
 349             }
 350             userFuture.setException(throwable);
 351             // There is no point in keeping this session. Reconnect.
 352             disconnect();
 353         }
 354     }
 355
 356     /**
 357      * Proxy for {@link Rpcs} which attaches a reset-keepalive-task and schedule request-timeout-task to each RPC
 358      * invocation. Version for {@link Rpcs.Normalized}.
 359      */
 360     private final class NormalizedKeepaliveRpcs implements Rpcs.Normalized {
 361         private final @NonNull KeepaliveDOMRpcService domRpcService;
 362         private final Rpcs.Normalized delegate;
 363
 364         NormalizedKeepaliveRpcs(final Rpcs.Normalized delegate) {
 365             this.delegate = requireNonNull(delegate);
 366             domRpcService = new KeepaliveDOMRpcService(delegate.domRpcService());
 367         }
 368
 369         @Override
 370         public ListenableFuture<? extends DOMRpcResult> invokeNetconf(final QName type, final ContainerNode input) {
 371             // FIXME: what happens if we disable keepalive and then invokeRpc() throws?
 372             disableKeepalive();
 373             return scheduleTimeout(delegate.invokeNetconf(type, input));
 374         }
 375
 376         @Override
 377         public DOMRpcService domRpcService() {
 378             return domRpcService;
 379         }
 380     }
 381
 382     private final class KeepaliveDOMRpcService implements DOMRpcService {
 383         private final @NonNull DOMRpcService delegate;
 384
 385         KeepaliveDOMRpcService(final DOMRpcService delegate) {
 386             this.delegate = requireNonNull(delegate);
 387         }
 388
 389         @Override
 390         public ListenableFuture<? extends DOMRpcResult> invokeRpc(final QName type, final ContainerNode input) {
 391             // FIXME: what happens if we disable keepalive and then invokeRpc() throws?
 392             disableKeepalive();
 393             return scheduleTimeout(delegate.invokeRpc(type, input));
 394         }
 395
 396         @Override
 397         public Registration registerRpcListener(final DOMRpcAvailabilityListener rpcListener) {
 398             // There is no real communication with the device (yet), hence no recordActivity() or anything
 399             return delegate.registerRpcListener(rpcListener);
 400         }
 401     }
 402
 403     /**
 404      * Proxy for {@link Rpcs} which attaches a reset-keepalive-task and schedule request-timeout-task to each RPC
 405      * invocation. Version for {@link Rpcs.Schemaless}.
 406      */
 407     private final class SchemalessKeepaliveRpcs implements Rpcs.Schemaless {
 408         private final @NonNull KeepaliveSchemalessRpcService schemalessRpcService;
 409         private final Rpcs.Schemaless delegate;
 410
 411         SchemalessKeepaliveRpcs(final Rpcs.Schemaless delegate) {
 412             this.delegate = requireNonNull(delegate);
 413             schemalessRpcService = new KeepaliveSchemalessRpcService(delegate.schemalessRpcService());
 414         }
 415
 416         @Override
 417         public ListenableFuture<? extends DOMRpcResult> invokeNetconf(final QName type, final ContainerNode input) {
 418             // FIXME: what happens if we disable keepalive and then invokeRpc() throws?
 419             disableKeepalive();
 420             return scheduleTimeout(delegate.invokeNetconf(type, input));
 421         }
 422
 423         @Override
 424         public SchemalessRpcService schemalessRpcService() {
 425             return schemalessRpcService;
 426         }
 427     }
 428
 429     private final class KeepaliveSchemalessRpcService implements SchemalessRpcService {
 430         private final SchemalessRpcService delegate;
 431
 432         KeepaliveSchemalessRpcService(final SchemalessRpcService delegate) {
 433             this.delegate = requireNonNull(delegate);
 434         }
 435
 436         @Override
 437         public ListenableFuture<? extends DOMSource> invokeRpc(final QName type, final DOMSource payload) {
 438             // FIXME: what happens if we disable keepalive and then invokeRpc() throws?
 439             disableKeepalive();
 440             return scheduleTimeout(delegate.invokeRpc(type, payload));
 441         }
 442     }
 443 }