netconf/sal-netconf-connector/src/main/java/org/opendaylight/netconf/sal/connect/netconf/NetconfDevice.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;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11 import static java.util.Objects.requireNonNull;
  12
  13 import com.google.common.base.Predicates;
  14 import com.google.common.collect.Collections2;
  15 import com.google.common.collect.Lists;
  16 import com.google.common.collect.Sets;
  17 import com.google.common.util.concurrent.FutureCallback;
  18 import com.google.common.util.concurrent.Futures;
  19 import com.google.common.util.concurrent.ListenableFuture;
  20 import com.google.common.util.concurrent.ListeningExecutorService;
  21 import com.google.common.util.concurrent.MoreExecutors;
  22 import io.netty.util.concurrent.EventExecutor;
  23 import java.util.ArrayList;
  24 import java.util.Collection;
  25 import java.util.Collections;
  26 import java.util.LinkedList;
  27 import java.util.List;
  28 import java.util.Optional;
  29 import java.util.Set;
  30 import java.util.concurrent.Callable;
  31 import java.util.concurrent.ExecutionException;
  32 import java.util.concurrent.TimeUnit;
  33 import java.util.stream.Collectors;
  34 import org.checkerframework.checker.lock.qual.GuardedBy;
  35 import org.opendaylight.mdsal.dom.api.DOMRpcResult;
  36 import org.opendaylight.mdsal.dom.api.DOMRpcService;
  37 import org.opendaylight.netconf.api.NetconfMessage;
  38 import org.opendaylight.netconf.sal.connect.api.DeviceActionFactory;
  39 import org.opendaylight.netconf.sal.connect.api.MessageTransformer;
  40 import org.opendaylight.netconf.sal.connect.api.NetconfDeviceSchemas;
  41 import org.opendaylight.netconf.sal.connect.api.NetconfDeviceSchemasResolver;
  42 import org.opendaylight.netconf.sal.connect.api.RemoteDevice;
  43 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceCommunicator;
  44 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceHandler;
  45 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfDeviceCapabilities;
  46 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfDeviceCommunicator;
  47 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfSessionPreferences;
  48 import org.opendaylight.netconf.sal.connect.netconf.sal.NetconfDeviceRpc;
  49 import org.opendaylight.netconf.sal.connect.netconf.schema.NetconfRemoteSchemaYangSourceProvider;
  50 import org.opendaylight.netconf.sal.connect.netconf.schema.YangLibrarySchemaYangSourceProvider;
  51 import org.opendaylight.netconf.sal.connect.netconf.schema.mapping.BaseSchema;
  52 import org.opendaylight.netconf.sal.connect.netconf.schema.mapping.NetconfMessageTransformer;
  53 import org.opendaylight.netconf.sal.connect.netconf.util.NetconfMessageTransformUtil;
  54 import org.opendaylight.netconf.sal.connect.util.RemoteDeviceId;
  55 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfCapabilityChange;
  56 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.optional.rev190614.NetconfNodeAugmentedOptional;
  57 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.NetconfNode;
  58 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.available.capabilities.AvailableCapabilityBuilder;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.unavailable.capabilities.UnavailableCapability;
  60 import org.opendaylight.yangtools.yang.common.QName;
  61 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  62 import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
  63 import org.opendaylight.yangtools.yang.model.repo.api.RevisionSourceIdentifier;
  64 import org.opendaylight.yangtools.yang.model.repo.api.SchemaContextFactory;
  65 import org.opendaylight.yangtools.yang.model.repo.api.SchemaRepository;
  66 import org.opendaylight.yangtools.yang.model.repo.api.SchemaResolutionException;
  67 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
  68 import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
  69 import org.opendaylight.yangtools.yang.model.repo.spi.PotentialSchemaSource;
  70 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceProvider;
  71 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistration;
  72 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistry;
  73 import org.slf4j.Logger;
  74 import org.slf4j.LoggerFactory;
  75
  76 /**
  77  *  This is a mediator between NetconfDeviceCommunicator and NetconfDeviceSalFacade.
  78  */
  79 public class NetconfDevice
  80         implements RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> {
  81
  82     private static final Logger LOG = LoggerFactory.getLogger(NetconfDevice.class);
  83
  84     protected final RemoteDeviceId id;
  85     protected final SchemaContextFactory schemaContextFactory;
  86     protected final SchemaSourceRegistry schemaRegistry;
  87     protected final SchemaRepository schemaRepository;
  88
  89     protected final List<SchemaSourceRegistration<?>> sourceRegistrations = new ArrayList<>();
  90
  91     private final RemoteDeviceHandler<NetconfSessionPreferences> salFacade;
  92     private final ListeningExecutorService processingExecutor;
  93     private final DeviceActionFactory deviceActionFactory;
  94     private final NetconfDeviceSchemasResolver stateSchemasResolver;
  95     private final NotificationHandler notificationHandler;
  96     private final boolean reconnectOnSchemasChange;
  97     private final NetconfNode node;
  98     private final EventExecutor eventExecutor;
  99     private final NetconfNodeAugmentedOptional nodeOptional;
 100
 101     @GuardedBy("this")
 102     private boolean connected = false;
 103
 104     // Message transformer is constructed once the schemas are available
 105     private MessageTransformer<NetconfMessage> messageTransformer;
 106
 107     /**
 108      * Create rpc implementation capable of handling RPC for monitoring and notifications
 109      * even before the schemas of remote device are downloaded.
 110      */
 111     static NetconfDeviceRpc getRpcForInitialization(final NetconfDeviceCommunicator listener,
 112                                                     final boolean notificationSupport) {
 113         final BaseSchema baseSchema = resolveBaseSchema(notificationSupport);
 114
 115         return new NetconfDeviceRpc(baseSchema.getSchemaContext(), listener,
 116                 new NetconfMessageTransformer(baseSchema.getSchemaContext(), false, baseSchema));
 117     }
 118
 119     private static BaseSchema resolveBaseSchema(final boolean notificationSupport) {
 120         return notificationSupport ? BaseSchema.BASE_NETCONF_CTX_WITH_NOTIFICATIONS : BaseSchema.BASE_NETCONF_CTX;
 121     }
 122
 123     public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final RemoteDeviceId id,
 124                          final RemoteDeviceHandler<NetconfSessionPreferences> salFacade,
 125                          final ListeningExecutorService globalProcessingExecutor,
 126                          final boolean reconnectOnSchemasChange) {
 127         this(schemaResourcesDTO, id, salFacade, globalProcessingExecutor, reconnectOnSchemasChange, null, null, null,
 128                 null);
 129     }
 130
 131     public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final RemoteDeviceId id,
 132             final RemoteDeviceHandler<NetconfSessionPreferences> salFacade,
 133             final ListeningExecutorService globalProcessingExecutor, final boolean reconnectOnSchemasChange,
 134             final DeviceActionFactory deviceActionFactory, final NetconfNode node, final EventExecutor eventExecutor,
 135             final NetconfNodeAugmentedOptional nodeOptional) {
 136         this.id = id;
 137         this.reconnectOnSchemasChange = reconnectOnSchemasChange;
 138         this.deviceActionFactory = deviceActionFactory;
 139         this.node = node;
 140         this.eventExecutor = eventExecutor;
 141         this.nodeOptional = nodeOptional;
 142         this.schemaRegistry = schemaResourcesDTO.getSchemaRegistry();
 143         this.schemaRepository = schemaResourcesDTO.getSchemaRepository();
 144         this.schemaContextFactory = schemaResourcesDTO.getSchemaContextFactory();
 145         this.salFacade = salFacade;
 146         this.stateSchemasResolver = schemaResourcesDTO.getStateSchemasResolver();
 147         this.processingExecutor = requireNonNull(globalProcessingExecutor);
 148         this.notificationHandler = new NotificationHandler(salFacade, id);
 149     }
 150
 151     @Override
 152     public void onRemoteSessionUp(final NetconfSessionPreferences remoteSessionCapabilities,
 153                                   final NetconfDeviceCommunicator listener) {
 154         // SchemaContext setup has to be performed in a dedicated thread since
 155         // we are in a netty thread in this method
 156         // Yang models are being downloaded in this method and it would cause a
 157         // deadlock if we used the netty thread
 158         // http://netty.io/wiki/thread-model.html
 159         setConnected(true);
 160         LOG.debug("{}: Session to remote device established with {}", id, remoteSessionCapabilities);
 161
 162         final NetconfDeviceRpc initRpc =
 163                 getRpcForInitialization(listener, remoteSessionCapabilities.isNotificationsSupported());
 164         final DeviceSourcesResolver task =
 165                 new DeviceSourcesResolver(remoteSessionCapabilities, id, stateSchemasResolver, initRpc,
 166                         resolveBaseSchema(remoteSessionCapabilities.isNotificationsSupported()).getSchemaContext());
 167         final ListenableFuture<DeviceSources> sourceResolverFuture = processingExecutor.submit(task);
 168
 169         if (shouldListenOnSchemaChange(remoteSessionCapabilities)) {
 170             registerToBaseNetconfStream(initRpc, listener);
 171         }
 172
 173         final FutureCallback<DeviceSources> resolvedSourceCallback = new FutureCallback<DeviceSources>() {
 174             @Override
 175             public void onSuccess(final DeviceSources result) {
 176                 addProvidedSourcesToSchemaRegistry(result);
 177                 setUpSchema(result);
 178             }
 179
 180             private void setUpSchema(final DeviceSources result) {
 181                 processingExecutor.submit(new SchemaSetup(result, remoteSessionCapabilities, listener));
 182             }
 183
 184             @Override
 185             public void onFailure(final Throwable throwable) {
 186                 LOG.warn("{}: Unexpected error resolving device sources", id, throwable);
 187                 handleSalInitializationFailure(throwable, listener);
 188             }
 189         };
 190
 191         Futures.addCallback(sourceResolverFuture, resolvedSourceCallback, MoreExecutors.directExecutor());
 192     }
 193
 194     private void registerToBaseNetconfStream(final NetconfDeviceRpc deviceRpc,
 195                                              final NetconfDeviceCommunicator listener) {
 196         // TODO check whether the model describing create subscription is present in schema
 197         // Perhaps add a default schema context to support create-subscription if the model was not provided
 198         // (same as what we do for base netconf operations in transformer)
 199         final ListenableFuture<DOMRpcResult> rpcResultListenableFuture = deviceRpc.invokeRpc(
 200                 NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_PATH,
 201                 NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_CONTENT);
 202
 203         Futures.addCallback(rpcResultListenableFuture, new FutureCallback<DOMRpcResult>() {
 204             @Override
 205             public void onSuccess(final DOMRpcResult domRpcResult) {
 206                 notificationHandler.addNotificationFilter(notification -> {
 207                     if (NetconfCapabilityChange.QNAME.equals(notification.getBody().getNodeType())) {
 208                         LOG.info("{}: Schemas change detected, reconnecting", id);
 209                         // Only disconnect is enough,
 210                         // the reconnecting nature of the connector will take care of reconnecting
 211                         listener.disconnect();
 212                         return Optional.empty();
 213                     }
 214                     return Optional.of(notification);
 215                 });
 216             }
 217
 218             @Override
 219             public void onFailure(final Throwable throwable) {
 220                 LOG.warn("Unable to subscribe to base notification stream. Schemas will not be reloaded on the fly",
 221                         throwable);
 222             }
 223         }, MoreExecutors.directExecutor());
 224     }
 225
 226     private boolean shouldListenOnSchemaChange(final NetconfSessionPreferences remoteSessionCapabilities) {
 227         return remoteSessionCapabilities.isNotificationsSupported() && reconnectOnSchemasChange;
 228     }
 229
 230     private synchronized void handleSalInitializationSuccess(final SchemaContext result,
 231                                         final NetconfSessionPreferences remoteSessionCapabilities,
 232                                         final DOMRpcService deviceRpc,
 233                                         final RemoteDeviceCommunicator<NetconfMessage> listener) {
 234         //NetconfDevice.SchemaSetup can complete after NetconfDeviceCommunicator was closed. In that case do nothing,
 235         //since salFacade.onDeviceDisconnected was already called.
 236         if (connected) {
 237             final BaseSchema baseSchema =
 238                 remoteSessionCapabilities.isNotificationsSupported()
 239                         ? BaseSchema.BASE_NETCONF_CTX_WITH_NOTIFICATIONS : BaseSchema.BASE_NETCONF_CTX;
 240             this.messageTransformer = new NetconfMessageTransformer(result, true, baseSchema);
 241
 242             // salFacade.onDeviceConnected has to be called before the notification handler is initialized
 243             this.salFacade.onDeviceConnected(result, remoteSessionCapabilities, deviceRpc,
 244                     this.deviceActionFactory == null ? null : this.deviceActionFactory.createDeviceAction(
 245                             this.messageTransformer, listener, result));
 246             this.notificationHandler.onRemoteSchemaUp(this.messageTransformer);
 247
 248             LOG.info("{}: Netconf connector initialized successfully", id);
 249         } else {
 250             LOG.warn("{}: Device communicator was closed before schema setup finished.", id);
 251         }
 252     }
 253
 254     private void handleSalInitializationFailure(final Throwable throwable,
 255                                                 final RemoteDeviceCommunicator<NetconfMessage> listener) {
 256         LOG.error("{}: Initialization in sal failed, disconnecting from device", id, throwable);
 257         listener.close();
 258         onRemoteSessionDown();
 259         resetMessageTransformer();
 260     }
 261
 262     /**
 263      * Set the transformer to null as is in initial state.
 264      */
 265     private void resetMessageTransformer() {
 266         updateTransformer(null);
 267     }
 268
 269     private synchronized void updateTransformer(final MessageTransformer<NetconfMessage> transformer) {
 270         messageTransformer = transformer;
 271     }
 272
 273     private synchronized void setConnected(final boolean connected) {
 274         this.connected = connected;
 275     }
 276
 277     private void addProvidedSourcesToSchemaRegistry(final DeviceSources deviceSources) {
 278         final SchemaSourceProvider<YangTextSchemaSource> yangProvider = deviceSources.getSourceProvider();
 279         for (final SourceIdentifier sourceId : deviceSources.getProvidedSources()) {
 280             sourceRegistrations.add(schemaRegistry.registerSchemaSource(yangProvider,
 281                     PotentialSchemaSource.create(
 282                             sourceId, YangTextSchemaSource.class, PotentialSchemaSource.Costs.REMOTE_IO.getValue())));
 283         }
 284     }
 285
 286     @Override
 287     public void onRemoteSessionDown() {
 288         setConnected(false);
 289         notificationHandler.onRemoteSchemaDown();
 290
 291         salFacade.onDeviceDisconnected();
 292         sourceRegistrations.forEach(SchemaSourceRegistration::close);
 293         sourceRegistrations.clear();
 294         resetMessageTransformer();
 295     }
 296
 297     @Override
 298     public void onRemoteSessionFailed(final Throwable throwable) {
 299         setConnected(false);
 300         salFacade.onDeviceFailed(throwable);
 301     }
 302
 303     @Override
 304     public void onNotification(final NetconfMessage notification) {
 305         notificationHandler.handleNotification(notification);
 306     }
 307
 308     /**
 309      * Just a transfer object containing schema related dependencies. Injected in constructor.
 310      */
 311     public static class SchemaResourcesDTO {
 312         private final SchemaSourceRegistry schemaRegistry;
 313         private final SchemaRepository schemaRepository;
 314         private final SchemaContextFactory schemaContextFactory;
 315         private final NetconfDeviceSchemasResolver stateSchemasResolver;
 316
 317         public SchemaResourcesDTO(final SchemaSourceRegistry schemaRegistry,
 318                                   final SchemaRepository schemaRepository,
 319                                   final SchemaContextFactory schemaContextFactory,
 320                                   final NetconfDeviceSchemasResolver deviceSchemasResolver) {
 321             this.schemaRegistry = requireNonNull(schemaRegistry);
 322             this.schemaRepository = requireNonNull(schemaRepository);
 323             this.schemaContextFactory = requireNonNull(schemaContextFactory);
 324             this.stateSchemasResolver = requireNonNull(deviceSchemasResolver);
 325         }
 326
 327         public SchemaSourceRegistry getSchemaRegistry() {
 328             return schemaRegistry;
 329         }
 330
 331         public SchemaRepository getSchemaRepository() {
 332             return schemaRepository;
 333         }
 334
 335         public SchemaContextFactory getSchemaContextFactory() {
 336             return schemaContextFactory;
 337         }
 338
 339         public NetconfDeviceSchemasResolver getStateSchemasResolver() {
 340             return stateSchemasResolver;
 341         }
 342     }
 343
 344     /**
 345      * Schema building callable.
 346      */
 347     private static class DeviceSourcesResolver implements Callable<DeviceSources> {
 348
 349         private final NetconfDeviceRpc deviceRpc;
 350         private final NetconfSessionPreferences remoteSessionCapabilities;
 351         private final RemoteDeviceId id;
 352         private final NetconfDeviceSchemasResolver stateSchemasResolver;
 353         private final SchemaContext schemaContext;
 354
 355         DeviceSourcesResolver(final NetconfDeviceRpc deviceRpc,
 356                               final NetconfSessionPreferences remoteSessionCapabilities,
 357                               final RemoteDeviceId id, final NetconfDeviceSchemasResolver stateSchemasResolver,
 358                               final SchemaContext schemaContext) {
 359             this.deviceRpc = deviceRpc;
 360             this.remoteSessionCapabilities = remoteSessionCapabilities;
 361             this.id = id;
 362             this.stateSchemasResolver = stateSchemasResolver;
 363             this.schemaContext = schemaContext;
 364         }
 365
 366         DeviceSourcesResolver(final NetconfSessionPreferences remoteSessionCapabilities, final RemoteDeviceId id,
 367                                      final NetconfDeviceSchemasResolver stateSchemasResolver,
 368                                      final NetconfDeviceRpc rpcForMonitoring, final SchemaContext schemaCtx) {
 369             this(rpcForMonitoring, remoteSessionCapabilities, id, stateSchemasResolver, schemaCtx);
 370         }
 371
 372         @Override
 373         public DeviceSources call() {
 374             final NetconfDeviceSchemas availableSchemas =
 375                     stateSchemasResolver.resolve(deviceRpc, remoteSessionCapabilities, id, schemaContext);
 376             LOG.debug("{}: Schemas exposed by ietf-netconf-monitoring: {}", id,
 377                     availableSchemas.getAvailableYangSchemasQNames());
 378
 379             final Set<QName> requiredSources = Sets.newHashSet(remoteSessionCapabilities.getModuleBasedCaps());
 380             final Set<QName> providedSources = availableSchemas.getAvailableYangSchemasQNames();
 381
 382             final Set<QName> requiredSourcesNotProvided = Sets.difference(requiredSources, providedSources);
 383             if (!requiredSourcesNotProvided.isEmpty()) {
 384                 LOG.warn("{}: Netconf device does not provide all yang models reported in hello message capabilities,"
 385                         + " required but not provided: {}", id, requiredSourcesNotProvided);
 386                 LOG.warn("{}: Attempting to build schema context from required sources", id);
 387             }
 388
 389             // Here all the sources reported in netconf monitoring are merged with those reported in hello.
 390             // It is necessary to perform this since submodules are not mentioned in hello but still required.
 391             // This clashes with the option of a user to specify supported yang models manually in configuration
 392             // for netconf-connector and as a result one is not able to fully override yang models of a device.
 393             // It is only possible to add additional models.
 394             final Set<QName> providedSourcesNotRequired = Sets.difference(providedSources, requiredSources);
 395             if (!providedSourcesNotRequired.isEmpty()) {
 396                 LOG.warn("{}: Netconf device provides additional yang models not reported in "
 397                         + "hello message capabilities: {}", id, providedSourcesNotRequired);
 398                 LOG.warn("{}: Adding provided but not required sources as required to prevent failures", id);
 399                 LOG.debug("{}: Netconf device reported in hello: {}", id, requiredSources);
 400                 requiredSources.addAll(providedSourcesNotRequired);
 401             }
 402
 403             final SchemaSourceProvider<YangTextSchemaSource> sourceProvider;
 404             if (availableSchemas instanceof LibraryModulesSchemas) {
 405                 sourceProvider = new YangLibrarySchemaYangSourceProvider(id,
 406                         ((LibraryModulesSchemas) availableSchemas).getAvailableModels());
 407             } else {
 408                 sourceProvider = new NetconfRemoteSchemaYangSourceProvider(id, deviceRpc);
 409             }
 410
 411             return new DeviceSources(requiredSources, providedSources, sourceProvider);
 412         }
 413     }
 414
 415     /**
 416      * Contains RequiredSources - sources from capabilities.
 417      */
 418     private static final class DeviceSources {
 419         private final Set<QName> requiredSources;
 420         private final Set<QName> providedSources;
 421         private final SchemaSourceProvider<YangTextSchemaSource> sourceProvider;
 422
 423         DeviceSources(final Set<QName> requiredSources, final Set<QName> providedSources,
 424                              final SchemaSourceProvider<YangTextSchemaSource> sourceProvider) {
 425             this.requiredSources = requiredSources;
 426             this.providedSources = providedSources;
 427             this.sourceProvider = sourceProvider;
 428         }
 429
 430         public Set<QName> getRequiredSourcesQName() {
 431             return requiredSources;
 432         }
 433
 434         public Set<QName> getProvidedSourcesQName() {
 435             return providedSources;
 436         }
 437
 438         public Collection<SourceIdentifier> getRequiredSources() {
 439             return Collections2.transform(requiredSources, DeviceSources::toSourceId);
 440         }
 441
 442         public Collection<SourceIdentifier> getProvidedSources() {
 443             return Collections2.transform(providedSources, DeviceSources::toSourceId);
 444         }
 445
 446         public SchemaSourceProvider<YangTextSchemaSource> getSourceProvider() {
 447             return sourceProvider;
 448         }
 449
 450         private static SourceIdentifier toSourceId(final QName input) {
 451             return RevisionSourceIdentifier.create(input.getLocalName(), input.getRevision());
 452         }
 453     }
 454
 455     /**
 456      * Schema builder that tries to build schema context from provided sources or biggest subset of it.
 457      */
 458     private final class SchemaSetup implements Runnable {
 459         private final DeviceSources deviceSources;
 460         private final NetconfSessionPreferences remoteSessionCapabilities;
 461         private final RemoteDeviceCommunicator<NetconfMessage> listener;
 462         private final NetconfDeviceCapabilities capabilities;
 463
 464         SchemaSetup(final DeviceSources deviceSources, final NetconfSessionPreferences remoteSessionCapabilities,
 465                            final RemoteDeviceCommunicator<NetconfMessage> listener) {
 466             this.deviceSources = deviceSources;
 467             this.remoteSessionCapabilities = remoteSessionCapabilities;
 468             this.listener = listener;
 469             this.capabilities = remoteSessionCapabilities.getNetconfDeviceCapabilities();
 470         }
 471
 472         @Override
 473         public void run() {
 474
 475             final Collection<SourceIdentifier> requiredSources = deviceSources.getRequiredSources();
 476             final Collection<SourceIdentifier> missingSources = filterMissingSources(requiredSources);
 477
 478             capabilities.addUnresolvedCapabilities(getQNameFromSourceIdentifiers(missingSources),
 479                     UnavailableCapability.FailureReason.MissingSource);
 480
 481             requiredSources.removeAll(missingSources);
 482             setUpSchema(requiredSources);
 483         }
 484
 485         private Collection<SourceIdentifier> filterMissingSources(final Collection<SourceIdentifier> requiredSources) {
 486             return requiredSources.parallelStream().filter(sourceIdentifier -> {
 487                 try {
 488                     schemaRepository.getSchemaSource(sourceIdentifier, YangTextSchemaSource.class).get();
 489                     return false;
 490                 } catch (InterruptedException | ExecutionException e) {
 491                     return true;
 492                 }
 493             }).collect(Collectors.toList());
 494         }
 495
 496         /**
 497          * Build schema context, in case of success or final failure notify device.
 498          *
 499          * @param requiredSources required sources
 500          */
 501         @SuppressWarnings("checkstyle:IllegalCatch")
 502         private void setUpSchema(Collection<SourceIdentifier> requiredSources) {
 503             while (!requiredSources.isEmpty()) {
 504                 LOG.trace("{}: Trying to build schema context from {}", id, requiredSources);
 505                 try {
 506                     final ListenableFuture<SchemaContext> schemaBuilderFuture = schemaContextFactory
 507                             .createSchemaContext(requiredSources);
 508                     final SchemaContext result = schemaBuilderFuture.get();
 509                     LOG.debug("{}: Schema context built successfully from {}", id, requiredSources);
 510                     final Collection<QName> filteredQNames = Sets.difference(deviceSources.getRequiredSourcesQName(),
 511                             capabilities.getUnresolvedCapabilites().keySet());
 512                     capabilities.addCapabilities(filteredQNames.stream().map(entry -> new AvailableCapabilityBuilder()
 513                             .setCapability(entry.toString()).setCapabilityOrigin(
 514                                     remoteSessionCapabilities.getModuleBasedCapsOrigin().get(entry)).build())
 515                             .collect(Collectors.toList()));
 516
 517                     capabilities.addNonModuleBasedCapabilities(remoteSessionCapabilities
 518                             .getNonModuleCaps().stream().map(entry -> new AvailableCapabilityBuilder()
 519                                     .setCapability(entry).setCapabilityOrigin(
 520                                             remoteSessionCapabilities.getNonModuleBasedCapsOrigin().get(entry)).build())
 521                             .collect(Collectors.toList()));
 522
 523                     handleSalInitializationSuccess(result, remoteSessionCapabilities, getDeviceSpecificRpc(result),
 524                             listener);
 525                     return;
 526                 } catch (final ExecutionException e) {
 527                     // schemaBuilderFuture.checkedGet() throws only SchemaResolutionException
 528                     // that might be wrapping a MissingSchemaSourceException so we need to look
 529                     // at the cause of the exception to make sure we don't misinterpret it.
 530                     final Throwable cause = e.getCause();
 531
 532                     if (cause instanceof MissingSchemaSourceException) {
 533                         requiredSources = handleMissingSchemaSourceException(
 534                                 requiredSources, (MissingSchemaSourceException) cause);
 535                         continue;
 536                     }
 537                     if (cause instanceof SchemaResolutionException) {
 538                         requiredSources = handleSchemaResolutionException(requiredSources,
 539                             (SchemaResolutionException) cause);
 540                     } else {
 541                         handleSalInitializationFailure(e, listener);
 542                         return;
 543                     }
 544                 } catch (final Exception e) {
 545                     // unknown error, fail
 546                     handleSalInitializationFailure(e, listener);
 547                     return;
 548                 }
 549             }
 550             // No more sources, fail or try to reconnect
 551             if (nodeOptional != null && nodeOptional.getIgnoreMissingSchemaSources().isAllowed()) {
 552                 eventExecutor.schedule(() -> {
 553                     LOG.warn("Reconnection is allowed! This can lead to unexpected errors at runtime.");
 554                     LOG.warn("{} : No more sources for schema context.", id);
 555                     LOG.info("{} : Try to remount device.", id);
 556                     onRemoteSessionDown();
 557                     salFacade.onDeviceReconnected(remoteSessionCapabilities, node);
 558                 }, nodeOptional.getIgnoreMissingSchemaSources().getReconnectTime(), TimeUnit.MILLISECONDS);
 559             } else {
 560                 final IllegalStateException cause =
 561                         new IllegalStateException(id + ": No more sources for schema context");
 562                 handleSalInitializationFailure(cause, listener);
 563                 salFacade.onDeviceFailed(cause);
 564             }
 565         }
 566
 567         private Collection<SourceIdentifier> handleMissingSchemaSourceException(
 568                 final Collection<SourceIdentifier> requiredSources, final MissingSchemaSourceException exception) {
 569             // In case source missing, try without it
 570             final SourceIdentifier missingSource = exception.getSourceId();
 571             LOG.warn("{}: Unable to build schema context, missing source {}, will reattempt without it",
 572                 id, missingSource);
 573             LOG.debug("{}: Unable to build schema context, missing source {}, will reattempt without it",
 574                 id, missingSource, exception);
 575             final Collection<QName> qNameOfMissingSource =
 576                 getQNameFromSourceIdentifiers(Sets.newHashSet(missingSource));
 577             if (!qNameOfMissingSource.isEmpty()) {
 578                 capabilities.addUnresolvedCapabilities(
 579                         qNameOfMissingSource, UnavailableCapability.FailureReason.MissingSource);
 580             }
 581             return stripUnavailableSource(requiredSources, missingSource);
 582         }
 583
 584         private Collection<SourceIdentifier> handleSchemaResolutionException(
 585             final Collection<SourceIdentifier> requiredSources, final SchemaResolutionException resolutionException) {
 586             // In case resolution error, try only with resolved sources
 587             // There are two options why schema resolution exception occurred : unsatisfied imports or flawed model
 588             // FIXME Do we really have assurance that these two cases cannot happen at once?
 589             if (resolutionException.getFailedSource() != null) {
 590                 // flawed model - exclude it
 591                 final SourceIdentifier failedSourceId = resolutionException.getFailedSource();
 592                 LOG.warn("{}: Unable to build schema context, failed to resolve source {}, will reattempt without it",
 593                     id, failedSourceId);
 594                 LOG.warn("{}: Unable to build schema context, failed to resolve source {}, will reattempt without it",
 595                     id, failedSourceId, resolutionException);
 596                 capabilities.addUnresolvedCapabilities(
 597                         getQNameFromSourceIdentifiers(Collections.singleton(failedSourceId)),
 598                         UnavailableCapability.FailureReason.UnableToResolve);
 599                 return stripUnavailableSource(requiredSources, resolutionException.getFailedSource());
 600             }
 601             // unsatisfied imports
 602             final Set<SourceIdentifier> unresolvedSources = resolutionException.getUnsatisfiedImports().keySet();
 603             capabilities.addUnresolvedCapabilities(getQNameFromSourceIdentifiers(unresolvedSources),
 604                 UnavailableCapability.FailureReason.UnableToResolve);
 605             LOG.warn("{}: Unable to build schema context, unsatisfied imports {}, will reattempt with resolved only",
 606                 id, resolutionException.getUnsatisfiedImports());
 607             LOG.debug("{}: Unable to build schema context, unsatisfied imports {}, will reattempt with resolved only",
 608                 id, resolutionException.getUnsatisfiedImports(), resolutionException);
 609             return resolutionException.getResolvedSources();
 610         }
 611
 612         protected NetconfDeviceRpc getDeviceSpecificRpc(final SchemaContext result) {
 613             return new NetconfDeviceRpc(result, listener, new NetconfMessageTransformer(result, true));
 614         }
 615
 616         private Collection<SourceIdentifier> stripUnavailableSource(final Collection<SourceIdentifier> requiredSources,
 617                                                                     final SourceIdentifier sourceIdToRemove) {
 618             final LinkedList<SourceIdentifier> sourceIdentifiers = Lists.newLinkedList(requiredSources);
 619             checkState(sourceIdentifiers.remove(sourceIdToRemove),
 620                     "%s: Trying to remove %s from %s failed", id, sourceIdToRemove, requiredSources);
 621             return sourceIdentifiers;
 622         }
 623
 624         private Collection<QName> getQNameFromSourceIdentifiers(final Collection<SourceIdentifier> identifiers) {
 625             final Collection<QName> qNames = Collections2.transform(identifiers, this::getQNameFromSourceIdentifier);
 626
 627             if (qNames.isEmpty()) {
 628                 LOG.debug("{}: Unable to map any source identifiers to a capability reported by device : {}", id,
 629                         identifiers);
 630             }
 631             return Collections2.filter(qNames, Predicates.notNull());
 632         }
 633
 634         private QName getQNameFromSourceIdentifier(final SourceIdentifier identifier) {
 635             // Required sources are all required and provided merged in DeviceSourcesResolver
 636             for (final QName qname : deviceSources.getRequiredSourcesQName()) {
 637                 if (!qname.getLocalName().equals(identifier.getName())) {
 638                     continue;
 639                 }
 640
 641                 if (identifier.getRevision().equals(qname.getRevision())) {
 642                     return qname;
 643                 }
 644             }
 645             LOG.warn("Unable to map identifier to a devices reported capability: {} Available: {}",identifier,
 646                     deviceSources.getRequiredSourcesQName());
 647             // return null since we cannot find the QName,
 648             // this capability will be removed from required sources and not reported as unresolved-capability
 649             return null;
 650         }
 651     }
 652 }