opendaylight/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.Function;
  11 import com.google.common.base.Optional;
  12 import com.google.common.base.Preconditions;
  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.Collection;
  23 import java.util.LinkedList;
  24 import java.util.List;
  25 import java.util.Set;
  26 import java.util.concurrent.Callable;
  27 import java.util.concurrent.ExecutorService;
  28 import org.opendaylight.controller.md.sal.dom.api.DOMNotification;
  29 import org.opendaylight.controller.md.sal.dom.api.DOMRpcException;
  30 import org.opendaylight.controller.md.sal.dom.api.DOMRpcResult;
  31 import org.opendaylight.controller.md.sal.dom.api.DOMRpcService;
  32 import org.opendaylight.netconf.api.NetconfMessage;
  33 import org.opendaylight.netconf.sal.connect.api.MessageTransformer;
  34 import org.opendaylight.netconf.sal.connect.api.RemoteDevice;
  35 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceCommunicator;
  36 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceHandler;
  37 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfDeviceCapabilities;
  38 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfDeviceCommunicator;
  39 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfSessionPreferences;
  40 import org.opendaylight.netconf.sal.connect.netconf.sal.NetconfDeviceRpc;
  41 import org.opendaylight.netconf.sal.connect.netconf.schema.NetconfRemoteSchemaYangSourceProvider;
  42 import org.opendaylight.netconf.sal.connect.netconf.schema.mapping.NetconfMessageTransformer;
  43 import org.opendaylight.netconf.sal.connect.netconf.util.NetconfMessageTransformUtil;
  44 import org.opendaylight.netconf.sal.connect.util.RemoteDeviceId;
  45 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.monitoring.extension.rev131210.$YangModuleInfoImpl;
  46 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfCapabilityChange;
  47 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.unavailable.capabilities.UnavailableCapability;
  48 import org.opendaylight.yangtools.sal.binding.generator.impl.ModuleInfoBackedContext;
  49 import org.opendaylight.yangtools.yang.common.QName;
  50 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  51 import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
  52 import org.opendaylight.yangtools.yang.model.repo.api.SchemaContextFactory;
  53 import org.opendaylight.yangtools.yang.model.repo.api.SchemaResolutionException;
  54 import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceRepresentation;
  55 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
  56 import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
  57 import org.opendaylight.yangtools.yang.model.repo.spi.PotentialSchemaSource;
  58 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistration;
  59 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistry;
  60 import org.slf4j.Logger;
  61 import org.slf4j.LoggerFactory;
  62
  63 /**
  64  *  This is a mediator between NetconfDeviceCommunicator and NetconfDeviceSalFacade
  65  */
  66 public class NetconfDevice implements RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> {
  67
  68     private static final Logger LOG = LoggerFactory.getLogger(NetconfDevice.class);
  69
  70     /**
  71      * Initial schema context contains schemas for netconf monitoring and netconf notifications
  72      */
  73     public static final SchemaContext INIT_SCHEMA_CTX;
  74
  75     static {
  76         try {
  77             final ModuleInfoBackedContext moduleInfoBackedContext = ModuleInfoBackedContext.create();
  78             moduleInfoBackedContext.addModuleInfos(
  79                     Lists.newArrayList(
  80                             $YangModuleInfoImpl.getInstance(),
  81                             org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.notification._1._0.rev080714.$YangModuleInfoImpl.getInstance(),
  82                             org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.base._1._0.rev110601.$YangModuleInfoImpl.getInstance()));
  83             INIT_SCHEMA_CTX = moduleInfoBackedContext.tryToCreateSchemaContext().get();
  84         } catch (final RuntimeException e) {
  85             LOG.error("Unable to prepare schema context for netconf initialization", e);
  86             throw new ExceptionInInitializerError(e);
  87         }
  88     }
  89
  90     public static final Function<QName, SourceIdentifier> QNAME_TO_SOURCE_ID_FUNCTION = new Function<QName, SourceIdentifier>() {
  91         @Override
  92         public SourceIdentifier apply(final QName input) {
  93             return new SourceIdentifier(input.getLocalName(), Optional.fromNullable(input.getFormattedRevision()));
  94         }
  95     };
  96
  97     protected final RemoteDeviceId id;
  98     private final boolean reconnectOnSchemasChange;
  99
 100     protected final SchemaContextFactory schemaContextFactory;
 101     private final RemoteDeviceHandler<NetconfSessionPreferences> salFacade;
 102     private final ListeningExecutorService processingExecutor;
 103     protected final SchemaSourceRegistry schemaRegistry;
 104     private final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver;
 105     private final NotificationHandler notificationHandler;
 106     protected final List<SchemaSourceRegistration<? extends SchemaSourceRepresentation>> sourceRegistrations = Lists.newArrayList();
 107
 108     // Message transformer is constructed once the schemas are available
 109     private MessageTransformer<NetconfMessage> messageTransformer;
 110
 111     public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final RemoteDeviceId id, final RemoteDeviceHandler<NetconfSessionPreferences> salFacade,
 112                          final ExecutorService globalProcessingExecutor) {
 113         this(schemaResourcesDTO, id, salFacade, globalProcessingExecutor, false);
 114     }
 115
 116     /**
 117      * Create rpc implementation capable of handling RPC for monitoring and notifications even before the schemas of remote device are downloaded
 118      */
 119     static NetconfDeviceRpc getRpcForInitialization(final NetconfDeviceCommunicator listener) {
 120         return new NetconfDeviceRpc(INIT_SCHEMA_CTX, listener, new NetconfMessageTransformer(INIT_SCHEMA_CTX, false));
 121     }
 122
 123
 124     // FIXME reduce parameters
 125     public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final RemoteDeviceId id, final RemoteDeviceHandler<NetconfSessionPreferences> salFacade,
 126                          final ExecutorService globalProcessingExecutor, final boolean reconnectOnSchemasChange) {
 127         this.id = id;
 128         this.reconnectOnSchemasChange = reconnectOnSchemasChange;
 129         this.schemaRegistry = schemaResourcesDTO.getSchemaRegistry();
 130         this.schemaContextFactory = schemaResourcesDTO.getSchemaContextFactory();
 131         this.salFacade = salFacade;
 132         this.stateSchemasResolver = schemaResourcesDTO.getStateSchemasResolver();
 133         this.processingExecutor = MoreExecutors.listeningDecorator(globalProcessingExecutor);
 134         this.notificationHandler = new NotificationHandler(salFacade, id);
 135     }
 136
 137     @Override
 138     public void onRemoteSessionUp(final NetconfSessionPreferences remoteSessionCapabilities,
 139                                   final NetconfDeviceCommunicator listener) {
 140         // SchemaContext setup has to be performed in a dedicated thread since
 141         // we are in a netty thread in this method
 142         // Yang models are being downloaded in this method and it would cause a
 143         // deadlock if we used the netty thread
 144         // http://netty.io/wiki/thread-model.html
 145         LOG.debug("{}: Session to remote device established with {}", id, remoteSessionCapabilities);
 146
 147         final NetconfDeviceRpc initRpc = getRpcForInitialization(listener);
 148         final DeviceSourcesResolver task = new DeviceSourcesResolver(remoteSessionCapabilities, id, stateSchemasResolver, initRpc);
 149         final ListenableFuture<DeviceSources> sourceResolverFuture = processingExecutor.submit(task);
 150
 151         if (shouldListenOnSchemaChange(remoteSessionCapabilities)) {
 152             registerToBaseNetconfStream(initRpc, listener);
 153         }
 154
 155         final FutureCallback<DeviceSources> resolvedSourceCallback = new FutureCallback<DeviceSources>() {
 156             @Override
 157             public void onSuccess(final DeviceSources result) {
 158                 addProvidedSourcesToSchemaRegistry(initRpc, result);
 159                 setUpSchema(result);
 160             }
 161
 162             private void setUpSchema(final DeviceSources result) {
 163                 processingExecutor.submit(new RecursiveSchemaSetup(result, remoteSessionCapabilities, listener));
 164             }
 165
 166             @Override
 167             public void onFailure(final Throwable t) {
 168                 LOG.warn("{}: Unexpected error resolving device sources: {}", id, t);
 169                 handleSalInitializationFailure(t, listener);
 170             }
 171         };
 172
 173         Futures.addCallback(sourceResolverFuture, resolvedSourceCallback);
 174     }
 175
 176     private void registerToBaseNetconfStream(final NetconfDeviceRpc deviceRpc, final NetconfDeviceCommunicator listener) {
 177        // TODO check whether the model describing create subscription is present in schema
 178         // Perhaps add a default schema context to support create-subscription if the model was not provided (same as what we do for base netconf operations in transformer)
 179         final CheckedFuture<DOMRpcResult, DOMRpcException> rpcResultListenableFuture =
 180                 deviceRpc.invokeRpc(NetconfMessageTransformUtil.toPath(NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_QNAME), NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_CONTENT);
 181
 182         final NotificationHandler.NotificationFilter filter = new NotificationHandler.NotificationFilter() {
 183             @Override
 184             public Optional<DOMNotification> filterNotification(final DOMNotification notification) {
 185                 if (isCapabilityChanged(notification)) {
 186                     LOG.info("{}: Schemas change detected, reconnecting", id);
 187                     // Only disconnect is enough, the reconnecting nature of the connector will take care of reconnecting
 188                     listener.disconnect();
 189                     return Optional.absent();
 190                 }
 191                 return Optional.of(notification);
 192             }
 193
 194             private boolean isCapabilityChanged(final DOMNotification notification) {
 195                 return notification.getBody().getNodeType().equals(NetconfCapabilityChange.QNAME);
 196             }
 197         };
 198
 199         Futures.addCallback(rpcResultListenableFuture, new FutureCallback<DOMRpcResult>() {
 200             @Override
 201             public void onSuccess(final DOMRpcResult domRpcResult) {
 202                 notificationHandler.addNotificationFilter(filter);
 203             }
 204
 205             @Override
 206             public void onFailure(final Throwable t) {
 207                 LOG.warn("Unable to subscribe to base notification stream. Schemas will not be reloaded on the fly", t);
 208             }
 209         });
 210     }
 211
 212     private boolean shouldListenOnSchemaChange(final NetconfSessionPreferences remoteSessionCapabilities) {
 213         return remoteSessionCapabilities.isNotificationsSupported() && reconnectOnSchemasChange;
 214     }
 215
 216     protected void handleSalInitializationSuccess(final SchemaContext result, final NetconfSessionPreferences remoteSessionCapabilities, final DOMRpcService deviceRpc) {
 217         messageTransformer = new NetconfMessageTransformer(result, true);
 218
 219         updateTransformer(messageTransformer);
 220         // salFacade.onDeviceConnected has to be called before the notification handler is initialized
 221         salFacade.onDeviceConnected(result, remoteSessionCapabilities, deviceRpc);
 222         notificationHandler.onRemoteSchemaUp(messageTransformer);
 223
 224         LOG.info("{}: Netconf connector initialized successfully", id);
 225     }
 226
 227     protected void handleSalInitializationFailure(final Throwable t, final RemoteDeviceCommunicator<NetconfMessage> listener) {
 228         LOG.error("{}: Initialization in sal failed, disconnecting from device", id, t);
 229         listener.close();
 230         onRemoteSessionDown();
 231         resetMessageTransformer();
 232     }
 233
 234     /**
 235      * Set the transformer to null as is in initial state
 236      */
 237     private void resetMessageTransformer() {
 238         updateTransformer(null);
 239     }
 240
 241     private void updateTransformer(final MessageTransformer<NetconfMessage> transformer) {
 242         messageTransformer = transformer;
 243     }
 244
 245     private void addProvidedSourcesToSchemaRegistry(final NetconfDeviceRpc deviceRpc, final DeviceSources deviceSources) {
 246         final NetconfRemoteSchemaYangSourceProvider yangProvider = new NetconfRemoteSchemaYangSourceProvider(id, deviceRpc);
 247         for (final SourceIdentifier sourceId : deviceSources.getProvidedSources()) {
 248             sourceRegistrations.add(schemaRegistry.registerSchemaSource(yangProvider,
 249                     PotentialSchemaSource.create(sourceId, YangTextSchemaSource.class, PotentialSchemaSource.Costs.REMOTE_IO.getValue())));
 250         }
 251     }
 252
 253     @Override
 254     public void onRemoteSessionDown() {
 255         notificationHandler.onRemoteSchemaDown();
 256
 257         salFacade.onDeviceDisconnected();
 258         for (final SchemaSourceRegistration<? extends SchemaSourceRepresentation> sourceRegistration : sourceRegistrations) {
 259             sourceRegistration.close();
 260         }
 261         resetMessageTransformer();
 262     }
 263
 264     @Override
 265     public void onRemoteSessionFailed(final Throwable throwable) {
 266         salFacade.onDeviceFailed(throwable);
 267     }
 268
 269     @Override
 270     public void onNotification(final NetconfMessage notification) {
 271         notificationHandler.handleNotification(notification);
 272     }
 273
 274     /**
 275      * Just a transfer object containing schema related dependencies. Injected in constructor.
 276      */
 277     public static class SchemaResourcesDTO {
 278         private final SchemaSourceRegistry schemaRegistry;
 279         private final SchemaContextFactory schemaContextFactory;
 280         private final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver;
 281
 282         public SchemaResourcesDTO(final SchemaSourceRegistry schemaRegistry, final SchemaContextFactory schemaContextFactory, final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver) {
 283             this.schemaRegistry = Preconditions.checkNotNull(schemaRegistry);
 284             this.schemaContextFactory = Preconditions.checkNotNull(schemaContextFactory);
 285             this.stateSchemasResolver = Preconditions.checkNotNull(stateSchemasResolver);
 286         }
 287
 288         public SchemaSourceRegistry getSchemaRegistry() {
 289             return schemaRegistry;
 290         }
 291
 292         public SchemaContextFactory getSchemaContextFactory() {
 293             return schemaContextFactory;
 294         }
 295
 296         public NetconfStateSchemas.NetconfStateSchemasResolver getStateSchemasResolver() {
 297             return stateSchemasResolver;
 298         }
 299     }
 300
 301     /**
 302      * Schema building callable.
 303      */
 304     private static class DeviceSourcesResolver implements Callable<DeviceSources> {
 305
 306         private final NetconfDeviceRpc deviceRpc;
 307         private final NetconfSessionPreferences remoteSessionCapabilities;
 308         private final RemoteDeviceId id;
 309         private final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver;
 310
 311         DeviceSourcesResolver(final NetconfDeviceRpc deviceRpc, final NetconfSessionPreferences remoteSessionCapabilities,
 312                                      final RemoteDeviceId id, final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver) {
 313             this.deviceRpc = deviceRpc;
 314             this.remoteSessionCapabilities = remoteSessionCapabilities;
 315             this.id = id;
 316             this.stateSchemasResolver = stateSchemasResolver;
 317         }
 318
 319         public DeviceSourcesResolver(final NetconfSessionPreferences remoteSessionCapabilities, final RemoteDeviceId id, final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver, final NetconfDeviceRpc rpcForMonitoring) {
 320             this(rpcForMonitoring, remoteSessionCapabilities, id, stateSchemasResolver);
 321         }
 322
 323         @Override
 324         public DeviceSources call() throws Exception {
 325             final NetconfStateSchemas availableSchemas = stateSchemasResolver.resolve(deviceRpc, remoteSessionCapabilities, id);
 326             LOG.debug("{}: Schemas exposed by ietf-netconf-monitoring: {}", id, availableSchemas.getAvailableYangSchemasQNames());
 327
 328             final Set<QName> requiredSources = Sets.newHashSet(remoteSessionCapabilities.getModuleBasedCaps());
 329             final Set<QName> providedSources = availableSchemas.getAvailableYangSchemasQNames();
 330
 331             final Set<QName> requiredSourcesNotProvided = Sets.difference(requiredSources, providedSources);
 332             if (!requiredSourcesNotProvided.isEmpty()) {
 333                 LOG.warn("{}: Netconf device does not provide all yang models reported in hello message capabilities, required but not provided: {}",
 334                         id, requiredSourcesNotProvided);
 335                 LOG.warn("{}: Attempting to build schema context from required sources", id);
 336             }
 337
 338             // Here all the sources reported in netconf monitoring are merged with those reported in hello.
 339             // It is necessary to perform this since submodules are not mentioned in hello but still required.
 340             // This clashes with the option of a user to specify supported yang models manually in configuration for netconf-connector
 341             // and as a result one is not able to fully override yang models of a device. It is only possible to add additional models.
 342             final Set<QName> providedSourcesNotRequired = Sets.difference(providedSources, requiredSources);
 343             if (!providedSourcesNotRequired.isEmpty()) {
 344                 LOG.warn("{}: Netconf device provides additional yang models not reported in hello message capabilities: {}",
 345                         id, providedSourcesNotRequired);
 346                 LOG.warn("{}: Adding provided but not required sources as required to prevent failures", id);
 347                 LOG.debug("{}: Netconf device reported in hello: {}", id, requiredSources);
 348                 requiredSources.addAll(providedSourcesNotRequired);
 349             }
 350
 351             return new DeviceSources(requiredSources, providedSources);
 352         }
 353     }
 354
 355     /**
 356      * Contains RequiredSources - sources from capabilities.
 357      */
 358     private static final class DeviceSources {
 359         private final Set<QName> requiredSources;
 360         private final Set<QName> providedSources;
 361
 362         public DeviceSources(final Set<QName> requiredSources, final Set<QName> providedSources) {
 363             this.requiredSources = requiredSources;
 364             this.providedSources = providedSources;
 365         }
 366
 367         public Set<QName> getRequiredSourcesQName() {
 368             return requiredSources;
 369         }
 370
 371         public Set<QName> getProvidedSourcesQName() {
 372             return providedSources;
 373         }
 374
 375         public Collection<SourceIdentifier> getRequiredSources() {
 376             return Collections2.transform(requiredSources, QNAME_TO_SOURCE_ID_FUNCTION);
 377         }
 378
 379         public Collection<SourceIdentifier> getProvidedSources() {
 380             return Collections2.transform(providedSources, QNAME_TO_SOURCE_ID_FUNCTION);
 381         }
 382
 383     }
 384
 385     /**
 386      * Schema builder that tries to build schema context from provided sources or biggest subset of it.
 387      */
 388     private final class RecursiveSchemaSetup implements Runnable {
 389         private final DeviceSources deviceSources;
 390         private final NetconfSessionPreferences remoteSessionCapabilities;
 391         private final RemoteDeviceCommunicator<NetconfMessage> listener;
 392         private final NetconfDeviceCapabilities capabilities;
 393
 394         public RecursiveSchemaSetup(final DeviceSources deviceSources, final NetconfSessionPreferences remoteSessionCapabilities, final RemoteDeviceCommunicator<NetconfMessage> listener) {
 395             this.deviceSources = deviceSources;
 396             this.remoteSessionCapabilities = remoteSessionCapabilities;
 397             this.listener = listener;
 398             this.capabilities = remoteSessionCapabilities.getNetconfDeviceCapabilities();
 399         }
 400
 401         @Override
 402         public void run() {
 403             setUpSchema(deviceSources.getRequiredSources());
 404         }
 405
 406         /**
 407          * Recursively build schema context, in case of success or final failure notify device
 408          */
 409         // FIXME reimplement without recursion
 410         private void setUpSchema(final Collection<SourceIdentifier> requiredSources) {
 411             LOG.trace("{}: Trying to build schema context from {}", id, requiredSources);
 412
 413             // If no more sources, fail
 414             if(requiredSources.isEmpty()) {
 415                 final IllegalStateException cause = new IllegalStateException(id + ": No more sources for schema context");
 416                 handleSalInitializationFailure(cause, listener);
 417                 salFacade.onDeviceFailed(cause);
 418                 return;
 419             }
 420
 421             final CheckedFuture<SchemaContext, SchemaResolutionException> schemaBuilderFuture = schemaContextFactory.createSchemaContext(requiredSources);
 422
 423             final FutureCallback<SchemaContext> RecursiveSchemaBuilderCallback = new FutureCallback<SchemaContext>() {
 424
 425                 @Override
 426                 public void onSuccess(final SchemaContext result) {
 427                     LOG.debug("{}: Schema context built successfully from {}", id, requiredSources);
 428                     final Collection<QName> filteredQNames = Sets.difference(deviceSources.getProvidedSourcesQName(), capabilities.getUnresolvedCapabilites().keySet());
 429                     capabilities.addCapabilities(filteredQNames);
 430                     capabilities.addNonModuleBasedCapabilities(remoteSessionCapabilities.getNonModuleCaps());
 431                     handleSalInitializationSuccess(result, remoteSessionCapabilities, getDeviceSpecificRpc(result));
 432                 }
 433
 434                 @Override
 435                 public void onFailure(final Throwable t) {
 436                     // In case source missing, try without it
 437                     if (t instanceof MissingSchemaSourceException) {
 438                         final SourceIdentifier missingSource = ((MissingSchemaSourceException) t).getSourceId();
 439                         LOG.warn("{}: Unable to build schema context, missing source {}, will reattempt without it", id, missingSource);
 440                         capabilities.addUnresolvedCapabilities(getQNameFromSourceIdentifiers(Sets.newHashSet(missingSource)), UnavailableCapability.FailureReason.MissingSource);
 441                         setUpSchema(stripMissingSource(requiredSources, missingSource));
 442
 443                     // In case resolution error, try only with resolved sources
 444                     } else if (t instanceof SchemaResolutionException) {
 445                         // TODO check for infinite loop
 446                         final SchemaResolutionException resolutionException = (SchemaResolutionException) t;
 447                         final Set<SourceIdentifier> unresolvedSources = resolutionException.getUnsatisfiedImports().keySet();
 448                         capabilities.addUnresolvedCapabilities(getQNameFromSourceIdentifiers(unresolvedSources), UnavailableCapability.FailureReason.UnableToResolve);
 449                         LOG.warn("{}: Unable to build schema context, unsatisfied imports {}, will reattempt with resolved only", id, resolutionException.getUnsatisfiedImports());
 450                         setUpSchema(resolutionException.getResolvedSources());
 451                     // unknown error, fail
 452                     } else {
 453                         handleSalInitializationFailure(t, listener);
 454                     }
 455                 }
 456             };
 457
 458             Futures.addCallback(schemaBuilderFuture, RecursiveSchemaBuilderCallback);
 459         }
 460
 461         protected NetconfDeviceRpc getDeviceSpecificRpc(final SchemaContext result) {
 462             return new NetconfDeviceRpc(result, listener, new NetconfMessageTransformer(result, true));
 463         }
 464
 465         private Collection<SourceIdentifier> stripMissingSource(final Collection<SourceIdentifier> requiredSources, final SourceIdentifier sIdToRemove) {
 466             final LinkedList<SourceIdentifier> sourceIdentifiers = Lists.newLinkedList(requiredSources);
 467             final boolean removed = sourceIdentifiers.remove(sIdToRemove);
 468             Preconditions.checkState(removed, "{}: Trying to remove {} from {} failed", id, sIdToRemove, requiredSources);
 469             return sourceIdentifiers;
 470         }
 471
 472         private Collection<QName> getQNameFromSourceIdentifiers(final Collection<SourceIdentifier> identifiers) {
 473             final Collection<QName> qNames = Collections2.transform(identifiers, new Function<SourceIdentifier, QName>() {
 474                 @Override
 475                 public QName apply(final SourceIdentifier sourceIdentifier) {
 476                     return getQNameFromSourceIdentifier(sourceIdentifier);
 477                 }
 478             });
 479
 480             if (qNames.isEmpty()) {
 481                 LOG.debug("{}: Unable to map any source identfiers to a capability reported by device : {}", id, identifiers);
 482             }
 483             return qNames;
 484         }
 485
 486         private QName getQNameFromSourceIdentifier(final SourceIdentifier identifier) {
 487             // Required sources are all required and provided merged in DeviceSourcesResolver
 488             for (final QName qname : deviceSources.getRequiredSourcesQName()) {
 489                 if(qname.getLocalName().equals(identifier.getName()) == false) {
 490                     continue;
 491                 }
 492
 493                 if(identifier.getRevision().equals(SourceIdentifier.NOT_PRESENT_FORMATTED_REVISION) &&
 494                         qname.getRevision() == null) {
 495                     return qname;
 496                 }
 497
 498                 if (qname.getFormattedRevision().equals(identifier.getRevision())) {
 499                     return qname;
 500                 }
 501             }
 502             throw new IllegalArgumentException("Unable to map identifier to a devices reported capability: " + identifier + " Available: " + deviceSources.getRequiredSourcesQName());
 503         }
 504     }
 505 }