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