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 import static org.opendaylight.netconf.sal.connect.netconf.util.NetconfMessageTransformUtil.NETCONF_GET_NODEID;
  13
  14 import com.google.common.base.Predicates;
  15 import com.google.common.collect.Collections2;
  16 import com.google.common.collect.ImmutableMap;
  17 import com.google.common.collect.ImmutableSet;
  18 import com.google.common.collect.Sets;
  19 import com.google.common.util.concurrent.FutureCallback;
  20 import com.google.common.util.concurrent.Futures;
  21 import com.google.common.util.concurrent.ListenableFuture;
  22 import com.google.common.util.concurrent.ListeningExecutorService;
  23 import com.google.common.util.concurrent.MoreExecutors;
  24 import com.google.common.util.concurrent.SettableFuture;
  25 import java.util.ArrayList;
  26 import java.util.Arrays;
  27 import java.util.Collection;
  28 import java.util.HashMap;
  29 import java.util.HashSet;
  30 import java.util.List;
  31 import java.util.Map;
  32 import java.util.Objects;
  33 import java.util.Set;
  34 import java.util.concurrent.ExecutionException;
  35 import java.util.stream.Collectors;
  36 import org.checkerframework.checker.lock.qual.GuardedBy;
  37 import org.eclipse.jdt.annotation.NonNull;
  38 import org.opendaylight.mdsal.dom.api.DOMRpcResult;
  39 import org.opendaylight.mdsal.dom.api.DOMRpcService;
  40 import org.opendaylight.netconf.api.NetconfMessage;
  41 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  42 import org.opendaylight.netconf.sal.connect.api.DeviceActionFactory;
  43 import org.opendaylight.netconf.sal.connect.api.MessageTransformer;
  44 import org.opendaylight.netconf.sal.connect.api.NetconfDeviceSchemasResolver;
  45 import org.opendaylight.netconf.sal.connect.api.RemoteDevice;
  46 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceCommunicator;
  47 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceHandler;
  48 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfDeviceCapabilities;
  49 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfDeviceCommunicator;
  50 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfSessionPreferences;
  51 import org.opendaylight.netconf.sal.connect.netconf.sal.NetconfDeviceRpc;
  52 import org.opendaylight.netconf.sal.connect.netconf.schema.mapping.BaseNetconfSchemas;
  53 import org.opendaylight.netconf.sal.connect.netconf.schema.mapping.BaseSchema;
  54 import org.opendaylight.netconf.sal.connect.netconf.schema.mapping.NetconfMessageTransformer;
  55 import org.opendaylight.netconf.sal.connect.netconf.util.NetconfMessageTransformUtil;
  56 import org.opendaylight.netconf.sal.connect.util.RemoteDeviceId;
  57 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfCapabilityChange;
  58 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.available.capabilities.AvailableCapability;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.available.capabilities.AvailableCapabilityBuilder;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.unavailable.capabilities.UnavailableCapability;
  61 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.unavailable.capabilities.UnavailableCapability.FailureReason;
  62 import org.opendaylight.yangtools.concepts.Registration;
  63 import org.opendaylight.yangtools.rfc8528.data.api.MountPointContext;
  64 import org.opendaylight.yangtools.rfc8528.data.util.EmptyMountPointContext;
  65 import org.opendaylight.yangtools.rfc8528.model.api.SchemaMountConstants;
  66 import org.opendaylight.yangtools.yang.common.QName;
  67 import org.opendaylight.yangtools.yang.common.RpcError;
  68 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  69 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  70 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  71 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  72 import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
  73 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  74 import org.opendaylight.yangtools.yang.model.repo.api.EffectiveModelContextFactory;
  75 import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
  76 import org.opendaylight.yangtools.yang.model.repo.api.SchemaRepository;
  77 import org.opendaylight.yangtools.yang.model.repo.api.SchemaResolutionException;
  78 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
  79 import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
  80 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistry;
  81 import org.slf4j.Logger;
  82 import org.slf4j.LoggerFactory;
  83
  84 /**
  85  *  This is a mediator between NetconfDeviceCommunicator and NetconfDeviceSalFacade.
  86  */
  87 public class NetconfDevice implements RemoteDevice<NetconfDeviceCommunicator> {
  88     private static final Logger LOG = LoggerFactory.getLogger(NetconfDevice.class);
  89
  90     private static final QName RFC8528_SCHEMA_MOUNTS_QNAME = QName.create(
  91         SchemaMountConstants.RFC8528_MODULE, "schema-mounts").intern();
  92     private static final YangInstanceIdentifier RFC8528_SCHEMA_MOUNTS = YangInstanceIdentifier.create(
  93         NodeIdentifier.create(RFC8528_SCHEMA_MOUNTS_QNAME));
  94
  95     protected final RemoteDeviceId id;
  96     protected final EffectiveModelContextFactory schemaContextFactory;
  97     protected final SchemaSourceRegistry schemaRegistry;
  98     protected final SchemaRepository schemaRepository;
  99
 100     protected final List<Registration> sourceRegistrations = new ArrayList<>();
 101
 102     private final RemoteDeviceHandler salFacade;
 103     private final ListeningExecutorService processingExecutor;
 104     private final DeviceActionFactory deviceActionFactory;
 105     private final NetconfDeviceSchemasResolver stateSchemasResolver;
 106     private final NotificationHandler notificationHandler;
 107     private final boolean reconnectOnSchemasChange;
 108     private final BaseNetconfSchemas baseSchemas;
 109
 110     @GuardedBy("this")
 111     private boolean connected = false;
 112
 113     // Message transformer is constructed once the schemas are available
 114     private MessageTransformer messageTransformer;
 115
 116     public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final BaseNetconfSchemas baseSchemas,
 117             final RemoteDeviceId id, final RemoteDeviceHandler salFacade,
 118             final ListeningExecutorService globalProcessingExecutor, final boolean reconnectOnSchemasChange) {
 119         this(schemaResourcesDTO, baseSchemas, id, salFacade, globalProcessingExecutor, reconnectOnSchemasChange, null);
 120     }
 121
 122     public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final BaseNetconfSchemas baseSchemas,
 123             final RemoteDeviceId id, final RemoteDeviceHandler salFacade,
 124             final ListeningExecutorService globalProcessingExecutor, final boolean reconnectOnSchemasChange,
 125             final DeviceActionFactory deviceActionFactory) {
 126         this.baseSchemas = requireNonNull(baseSchemas);
 127         this.id = id;
 128         this.reconnectOnSchemasChange = reconnectOnSchemasChange;
 129         this.deviceActionFactory = deviceActionFactory;
 130         schemaRegistry = schemaResourcesDTO.getSchemaRegistry();
 131         schemaRepository = schemaResourcesDTO.getSchemaRepository();
 132         schemaContextFactory = schemaResourcesDTO.getSchemaContextFactory();
 133         this.salFacade = salFacade;
 134         stateSchemasResolver = schemaResourcesDTO.getStateSchemasResolver();
 135         processingExecutor = requireNonNull(globalProcessingExecutor);
 136         notificationHandler = new NotificationHandler(salFacade, id);
 137     }
 138
 139     @Override
 140     public void onRemoteSessionUp(final NetconfSessionPreferences remoteSessionCapabilities,
 141                                   final NetconfDeviceCommunicator listener) {
 142         // SchemaContext setup has to be performed in a dedicated thread since
 143         // we are in a netty thread in this method
 144         // Yang models are being downloaded in this method and it would cause a
 145         // deadlock if we used the netty thread
 146         // http://netty.io/wiki/thread-model.html
 147         setConnected(true);
 148         LOG.debug("{}: Session to remote device established with {}", id, remoteSessionCapabilities);
 149
 150         final BaseSchema baseSchema = resolveBaseSchema(remoteSessionCapabilities.isNotificationsSupported());
 151         final NetconfDeviceRpc initRpc = new NetconfDeviceRpc(baseSchema.getEffectiveModelContext(), listener,
 152             new NetconfMessageTransformer(baseSchema.getMountPointContext(), false, baseSchema));
 153         final ListenableFuture<DeviceSources> sourceResolverFuture = processingExecutor.submit(
 154             new DeviceSourcesResolver(id, baseSchema, initRpc, remoteSessionCapabilities, stateSchemasResolver));
 155
 156         if (shouldListenOnSchemaChange(remoteSessionCapabilities)) {
 157             registerToBaseNetconfStream(initRpc, listener);
 158         }
 159
 160         // Set up the SchemaContext for the device
 161         final ListenableFuture<SchemaResult> futureSchema = Futures.transformAsync(sourceResolverFuture,
 162             deviceSources -> assembleSchemaContext(deviceSources, remoteSessionCapabilities), processingExecutor);
 163
 164         // Potentially acquire mount point list and interpret it
 165         final ListenableFuture<NetconfDeviceSchema> futureContext = Futures.transformAsync(futureSchema,
 166             result -> Futures.transform(createMountPointContext(result.modelContext(), baseSchema, listener),
 167                 mount -> new NetconfDeviceSchema(result.capabilities(), mount), processingExecutor),
 168             processingExecutor);
 169
 170         Futures.addCallback(futureContext, new FutureCallback<>() {
 171             @Override
 172             public void onSuccess(final NetconfDeviceSchema result) {
 173                 handleSalInitializationSuccess(result, remoteSessionCapabilities,
 174                         getDeviceSpecificRpc(result.mountContext(), listener, baseSchema), listener);
 175             }
 176
 177             @Override
 178             public void onFailure(final Throwable cause) {
 179                 LOG.warn("{}: Unexpected error resolving device sources", id, cause);
 180                 // FIXME: this causes salFacade to see onDeviceDisconnected() and then onDeviceFailed(), which is quite
 181                 //        weird
 182                 handleSalInitializationFailure(cause, listener);
 183                 salFacade.onDeviceFailed(cause);
 184             }
 185         }, MoreExecutors.directExecutor());
 186     }
 187
 188     private void registerToBaseNetconfStream(final NetconfDeviceRpc deviceRpc,
 189                                              final NetconfDeviceCommunicator listener) {
 190         // TODO check whether the model describing create subscription is present in schema
 191         // Perhaps add a default schema context to support create-subscription if the model was not provided
 192         // (same as what we do for base netconf operations in transformer)
 193         final ListenableFuture<DOMRpcResult> rpcResultListenableFuture = deviceRpc.invokeRpc(
 194                 NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_QNAME,
 195                 NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_CONTENT);
 196
 197         Futures.addCallback(rpcResultListenableFuture, new FutureCallback<DOMRpcResult>() {
 198             @Override
 199             public void onSuccess(final DOMRpcResult domRpcResult) {
 200                 notificationHandler.addNotificationFilter(notification -> {
 201                     if (NetconfCapabilityChange.QNAME.equals(notification.getBody().getIdentifier().getNodeType())) {
 202                         LOG.info("{}: Schemas change detected, reconnecting", id);
 203                         // Only disconnect is enough,
 204                         // the reconnecting nature of the connector will take care of reconnecting
 205                         listener.disconnect();
 206                         return false;
 207                     }
 208                     return true;
 209                 });
 210             }
 211
 212             @Override
 213             public void onFailure(final Throwable throwable) {
 214                 LOG.warn("Unable to subscribe to base notification stream. Schemas will not be reloaded on the fly",
 215                         throwable);
 216             }
 217         }, MoreExecutors.directExecutor());
 218     }
 219
 220     private boolean shouldListenOnSchemaChange(final NetconfSessionPreferences remoteSessionCapabilities) {
 221         return remoteSessionCapabilities.isNotificationsSupported() && reconnectOnSchemasChange;
 222     }
 223
 224     private synchronized void handleSalInitializationSuccess(final NetconfDeviceSchema deviceSchema,
 225             final NetconfSessionPreferences remoteSessionCapabilities, final DOMRpcService deviceRpc,
 226             final RemoteDeviceCommunicator listener) {
 227         //NetconfDevice.SchemaSetup can complete after NetconfDeviceCommunicator was closed. In that case do nothing,
 228         //since salFacade.onDeviceDisconnected was already called.
 229         if (connected) {
 230             final var mount = deviceSchema.mountContext();
 231             messageTransformer = new NetconfMessageTransformer(mount, true,
 232                 resolveBaseSchema(remoteSessionCapabilities.isNotificationsSupported()));
 233
 234             // salFacade.onDeviceConnected has to be called before the notification handler is initialized
 235             salFacade.onDeviceConnected(deviceSchema, remoteSessionCapabilities, deviceRpc,
 236                     deviceActionFactory == null ? null : deviceActionFactory.createDeviceAction(
 237                             messageTransformer, listener, mount.getEffectiveModelContext()));
 238             notificationHandler.onRemoteSchemaUp(messageTransformer);
 239
 240             LOG.info("{}: Netconf connector initialized successfully", id);
 241         } else {
 242             LOG.warn("{}: Device communicator was closed before schema setup finished.", id);
 243         }
 244     }
 245
 246     private void handleSalInitializationFailure(final Throwable throwable, final RemoteDeviceCommunicator listener) {
 247         LOG.error("{}: Initialization in sal failed, disconnecting from device", id, throwable);
 248         listener.close();
 249         onRemoteSessionDown();
 250         resetMessageTransformer();
 251     }
 252
 253     /**
 254      * Set the transformer to null as is in initial state.
 255      */
 256     private void resetMessageTransformer() {
 257         updateTransformer(null);
 258     }
 259
 260     private synchronized void updateTransformer(final MessageTransformer transformer) {
 261         messageTransformer = transformer;
 262     }
 263
 264     private synchronized void setConnected(final boolean connected) {
 265         this.connected = connected;
 266     }
 267
 268     private ListenableFuture<SchemaResult> assembleSchemaContext(final DeviceSources deviceSources,
 269             final NetconfSessionPreferences remoteSessionCapabilities) {
 270         LOG.debug("{}: Resolved device sources to {}", id, deviceSources);
 271
 272         sourceRegistrations.addAll(deviceSources.register(schemaRegistry));
 273
 274         return new SchemaSetup(deviceSources, remoteSessionCapabilities).startResolution();
 275     }
 276
 277     private ListenableFuture<@NonNull MountPointContext> createMountPointContext(
 278             final EffectiveModelContext schemaContext, final BaseSchema baseSchema,
 279             final NetconfDeviceCommunicator listener) {
 280         final MountPointContext emptyContext = new EmptyMountPointContext(schemaContext);
 281         if (schemaContext.findModule(SchemaMountConstants.RFC8528_MODULE).isEmpty()) {
 282             return Futures.immediateFuture(emptyContext);
 283         }
 284
 285         // Create a temporary RPC invoker and acquire the mount point tree
 286         LOG.debug("{}: Acquiring available mount points", id);
 287         final NetconfDeviceRpc deviceRpc = new NetconfDeviceRpc(schemaContext, listener,
 288             new NetconfMessageTransformer(emptyContext, false, baseSchema));
 289
 290         return Futures.transform(deviceRpc.invokeRpc(NetconfMessageTransformUtil.NETCONF_GET_QNAME,
 291             Builders.containerBuilder().withNodeIdentifier(NETCONF_GET_NODEID)
 292                 .withChild(NetconfMessageTransformUtil.toFilterStructure(RFC8528_SCHEMA_MOUNTS, schemaContext))
 293                 .build()), rpcResult -> processSchemaMounts(rpcResult, emptyContext), MoreExecutors.directExecutor());
 294     }
 295
 296     private MountPointContext processSchemaMounts(final DOMRpcResult rpcResult, final MountPointContext emptyContext) {
 297         final Collection<? extends RpcError> errors = rpcResult.getErrors();
 298         if (!errors.isEmpty()) {
 299             LOG.warn("{}: Schema-mounts acquisition resulted in errors {}", id, errors);
 300         }
 301         final NormalizedNode schemaMounts = rpcResult.getResult();
 302         if (schemaMounts == null) {
 303             LOG.debug("{}: device does not define any schema mounts", id);
 304             return emptyContext;
 305         }
 306         if (!(schemaMounts instanceof ContainerNode)) {
 307             LOG.warn("{}: ignoring non-container schema mounts {}", id, schemaMounts);
 308             return emptyContext;
 309         }
 310
 311         return DeviceMountPointContext.create(emptyContext, (ContainerNode) schemaMounts);
 312     }
 313
 314     @Override
 315     public void onRemoteSessionDown() {
 316         setConnected(false);
 317         notificationHandler.onRemoteSchemaDown();
 318
 319         salFacade.onDeviceDisconnected();
 320         sourceRegistrations.forEach(Registration::close);
 321         sourceRegistrations.clear();
 322         resetMessageTransformer();
 323     }
 324
 325     @Override
 326     public void onRemoteSessionFailed(final Throwable throwable) {
 327         setConnected(false);
 328         salFacade.onDeviceFailed(throwable);
 329     }
 330
 331     @Override
 332     public void onNotification(final NetconfMessage notification) {
 333         notificationHandler.handleNotification(notification);
 334     }
 335
 336     private BaseSchema resolveBaseSchema(final boolean notificationSupport) {
 337         return notificationSupport ? baseSchemas.getBaseSchemaWithNotifications() : baseSchemas.getBaseSchema();
 338     }
 339
 340     protected NetconfDeviceRpc getDeviceSpecificRpc(final MountPointContext result,
 341             final RemoteDeviceCommunicator listener, final BaseSchema schema) {
 342         return new NetconfDeviceRpc(result.getEffectiveModelContext(), listener,
 343             new NetconfMessageTransformer(result, true, schema));
 344     }
 345
 346     /**
 347      * Just a transfer object containing schema related dependencies. Injected in constructor.
 348      */
 349     public static class SchemaResourcesDTO {
 350         private final SchemaSourceRegistry schemaRegistry;
 351         private final SchemaRepository schemaRepository;
 352         private final EffectiveModelContextFactory schemaContextFactory;
 353         private final NetconfDeviceSchemasResolver stateSchemasResolver;
 354
 355         public SchemaResourcesDTO(final SchemaSourceRegistry schemaRegistry,
 356                                   final SchemaRepository schemaRepository,
 357                                   final EffectiveModelContextFactory schemaContextFactory,
 358                                   final NetconfDeviceSchemasResolver deviceSchemasResolver) {
 359             this.schemaRegistry = requireNonNull(schemaRegistry);
 360             this.schemaRepository = requireNonNull(schemaRepository);
 361             this.schemaContextFactory = requireNonNull(schemaContextFactory);
 362             stateSchemasResolver = requireNonNull(deviceSchemasResolver);
 363         }
 364
 365         public SchemaSourceRegistry getSchemaRegistry() {
 366             return schemaRegistry;
 367         }
 368
 369         public SchemaRepository getSchemaRepository() {
 370             return schemaRepository;
 371         }
 372
 373         public EffectiveModelContextFactory getSchemaContextFactory() {
 374             return schemaContextFactory;
 375         }
 376
 377         public NetconfDeviceSchemasResolver getStateSchemasResolver() {
 378             return stateSchemasResolver;
 379         }
 380     }
 381
 382     /**
 383      * A dedicated exception to indicate when we fail to setup an {@link EffectiveModelContext}.
 384      */
 385     public static final class EmptySchemaContextException extends Exception {
 386         private static final long serialVersionUID = 1L;
 387
 388         public EmptySchemaContextException(final String message) {
 389             super(message);
 390         }
 391     }
 392
 393     /**
 394      * {@link NetconfDeviceCapabilities} and {@link EffectiveModelContext}.
 395      */
 396     private record SchemaResult(
 397         @NonNull NetconfDeviceCapabilities capabilities,
 398         @NonNull EffectiveModelContext modelContext) {
 399
 400         SchemaResult {
 401             requireNonNull(capabilities);
 402             requireNonNull(modelContext);
 403         }
 404     }
 405
 406     /**
 407      * Schema builder that tries to build schema context from provided sources or biggest subset of it.
 408      */
 409     private final class SchemaSetup implements FutureCallback<EffectiveModelContext> {
 410         private final SettableFuture<SchemaResult> resultFuture = SettableFuture.create();
 411
 412         private final Set<AvailableCapability> nonModuleBasedCapabilities = new HashSet<>();
 413         private final Map<QName, FailureReason> unresolvedCapabilites = new HashMap<>();
 414         private final Set<AvailableCapability> resolvedCapabilities = new HashSet<>();
 415
 416         private final DeviceSources deviceSources;
 417         private final NetconfSessionPreferences remoteSessionCapabilities;
 418
 419         private Collection<SourceIdentifier> requiredSources;
 420
 421         SchemaSetup(final DeviceSources deviceSources, final NetconfSessionPreferences remoteSessionCapabilities) {
 422             this.deviceSources = deviceSources;
 423             this.remoteSessionCapabilities = remoteSessionCapabilities;
 424
 425             // If device supports notifications and does not contain necessary modules, add them automatically
 426             if (remoteSessionCapabilities.containsNonModuleCapability(
 427                     XmlNetconfConstants.URN_IETF_PARAMS_NETCONF_CAPABILITY_NOTIFICATION_1_0)) {
 428                 deviceSources.getRequiredSourcesQName().addAll(
 429                         Arrays.asList(
 430                                 org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.notification._1._0.rev080714
 431                                         .$YangModuleInfoImpl.getInstance().getName(),
 432                                 org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.yang.types.rev130715
 433                                         .$YangModuleInfoImpl.getInstance().getName()
 434                         )
 435                 );
 436             }
 437
 438             requiredSources = deviceSources.getRequiredSources();
 439             final Collection<SourceIdentifier> missingSources = filterMissingSources(requiredSources);
 440
 441             addUnresolvedCapabilities(getQNameFromSourceIdentifiers(missingSources),
 442                 UnavailableCapability.FailureReason.MissingSource);
 443             requiredSources.removeAll(missingSources);
 444         }
 445
 446         ListenableFuture<SchemaResult> startResolution() {
 447             trySetupSchema();
 448             return resultFuture;
 449         }
 450
 451         @Override
 452         public void onSuccess(final EffectiveModelContext result) {
 453             LOG.debug("{}: Schema context built successfully from {}", id, requiredSources);
 454
 455             final Collection<QName> filteredQNames = Sets.difference(deviceSources.getRequiredSourcesQName(),
 456                     unresolvedCapabilites.keySet());
 457             resolvedCapabilities.addAll(filteredQNames.stream()
 458                 .map(capability -> new AvailableCapabilityBuilder()
 459                     .setCapability(capability.toString())
 460                     .setCapabilityOrigin(remoteSessionCapabilities.capabilityOrigin(capability))
 461                     .build())
 462                 .collect(Collectors.toList()));
 463
 464             nonModuleBasedCapabilities.addAll(remoteSessionCapabilities.nonModuleCaps().keySet().stream()
 465                 .map(capability -> new AvailableCapabilityBuilder()
 466                     .setCapability(capability)
 467                     .setCapabilityOrigin(remoteSessionCapabilities.capabilityOrigin(capability))
 468                     .build())
 469                 .collect(Collectors.toList()));
 470
 471
 472             resultFuture.set(new SchemaResult(new NetconfDeviceCapabilities(ImmutableMap.copyOf(unresolvedCapabilites),
 473                 ImmutableSet.copyOf(resolvedCapabilities), ImmutableSet.copyOf(nonModuleBasedCapabilities)), result));
 474         }
 475
 476         @Override
 477         public void onFailure(final Throwable cause) {
 478             // schemaBuilderFuture.checkedGet() throws only SchemaResolutionException
 479             // that might be wrapping a MissingSchemaSourceException so we need to look
 480             // at the cause of the exception to make sure we don't misinterpret it.
 481             if (cause instanceof MissingSchemaSourceException) {
 482                 requiredSources = handleMissingSchemaSourceException((MissingSchemaSourceException) cause);
 483             } else if (cause instanceof SchemaResolutionException) {
 484                 requiredSources = handleSchemaResolutionException((SchemaResolutionException) cause);
 485             } else {
 486                 LOG.debug("Unhandled failure", cause);
 487                 resultFuture.setException(cause);
 488                 // No more trying...
 489                 return;
 490             }
 491
 492             trySetupSchema();
 493         }
 494
 495         private void trySetupSchema() {
 496             if (!requiredSources.isEmpty()) {
 497                 // Initiate async resolution, drive it back based on the result
 498                 LOG.trace("{}: Trying to build schema context from {}", id, requiredSources);
 499                 Futures.addCallback(schemaContextFactory.createEffectiveModelContext(requiredSources), this,
 500                     MoreExecutors.directExecutor());
 501             } else {
 502                 LOG.debug("{}: no more sources for schema context", id);
 503                 resultFuture.setException(new EmptySchemaContextException(id + ": No more sources for schema context"));
 504             }
 505         }
 506
 507         private List<SourceIdentifier> filterMissingSources(final Collection<SourceIdentifier> origSources) {
 508             return origSources.parallelStream().filter(sourceIdentifier -> {
 509                 try {
 510                     schemaRepository.getSchemaSource(sourceIdentifier, YangTextSchemaSource.class).get();
 511                     return false;
 512                 } catch (InterruptedException | ExecutionException e) {
 513                     return true;
 514                 }
 515             }).collect(Collectors.toList());
 516         }
 517
 518         private void addUnresolvedCapabilities(final Collection<QName> capabilities, final FailureReason reason) {
 519             for (QName s : capabilities) {
 520                 unresolvedCapabilites.put(s, reason);
 521             }
 522         }
 523
 524         private List<SourceIdentifier> handleMissingSchemaSourceException(
 525                 final MissingSchemaSourceException exception) {
 526             // In case source missing, try without it
 527             final SourceIdentifier missingSource = exception.getSourceId();
 528             LOG.warn("{}: Unable to build schema context, missing source {}, will reattempt without it",
 529                 id, missingSource);
 530             LOG.debug("{}: Unable to build schema context, missing source {}, will reattempt without it",
 531                 id, missingSource, exception);
 532             final var qNameOfMissingSource = getQNameFromSourceIdentifiers(Sets.newHashSet(missingSource));
 533             if (!qNameOfMissingSource.isEmpty()) {
 534                 addUnresolvedCapabilities(qNameOfMissingSource, UnavailableCapability.FailureReason.MissingSource);
 535             }
 536             return stripUnavailableSource(missingSource);
 537         }
 538
 539         private Collection<SourceIdentifier> handleSchemaResolutionException(
 540                 final SchemaResolutionException resolutionException) {
 541             // In case resolution error, try only with resolved sources
 542             // There are two options why schema resolution exception occurred : unsatisfied imports or flawed model
 543             // FIXME Do we really have assurance that these two cases cannot happen at once?
 544             if (resolutionException.getFailedSource() != null) {
 545                 // flawed model - exclude it
 546                 final SourceIdentifier failedSourceId = resolutionException.getFailedSource();
 547                 LOG.warn("{}: Unable to build schema context, failed to resolve source {}, will reattempt without it",
 548                     id, failedSourceId);
 549                 LOG.warn("{}: Unable to build schema context, failed to resolve source {}, will reattempt without it",
 550                     id, failedSourceId, resolutionException);
 551                 addUnresolvedCapabilities(getQNameFromSourceIdentifiers(List.of(failedSourceId)),
 552                         UnavailableCapability.FailureReason.UnableToResolve);
 553                 return stripUnavailableSource(resolutionException.getFailedSource());
 554             }
 555             // unsatisfied imports
 556             addUnresolvedCapabilities(
 557                 getQNameFromSourceIdentifiers(resolutionException.getUnsatisfiedImports().keySet()),
 558                 UnavailableCapability.FailureReason.UnableToResolve);
 559             LOG.warn("{}: Unable to build schema context, unsatisfied imports {}, will reattempt with resolved only",
 560                 id, resolutionException.getUnsatisfiedImports());
 561             LOG.debug("{}: Unable to build schema context, unsatisfied imports {}, will reattempt with resolved only",
 562                 id, resolutionException.getUnsatisfiedImports(), resolutionException);
 563             return resolutionException.getResolvedSources();
 564         }
 565
 566         private List<SourceIdentifier> stripUnavailableSource(final SourceIdentifier sourceIdToRemove) {
 567             final var tmp = new ArrayList<>(requiredSources);
 568             checkState(tmp.remove(sourceIdToRemove), "%s: Trying to remove %s from %s failed", id, sourceIdToRemove,
 569                 requiredSources);
 570             return tmp;
 571         }
 572
 573         private Collection<QName> getQNameFromSourceIdentifiers(final Collection<SourceIdentifier> identifiers) {
 574             final Collection<QName> qNames = Collections2.transform(identifiers, this::getQNameFromSourceIdentifier);
 575
 576             if (qNames.isEmpty()) {
 577                 LOG.debug("{}: Unable to map any source identifiers to a capability reported by device : {}", id,
 578                         identifiers);
 579             }
 580             return Collections2.filter(qNames, Predicates.notNull());
 581         }
 582
 583         private QName getQNameFromSourceIdentifier(final SourceIdentifier identifier) {
 584             // Required sources are all required and provided merged in DeviceSourcesResolver
 585             for (final QName qname : deviceSources.getRequiredSourcesQName()) {
 586                 if (!qname.getLocalName().equals(identifier.name().getLocalName())) {
 587                     continue;
 588                 }
 589
 590                 if (Objects.equals(identifier.revision(), qname.getRevision().orElse(null))) {
 591                     return qname;
 592                 }
 593             }
 594             LOG.warn("Unable to map identifier to a devices reported capability: {} Available: {}",identifier,
 595                     deviceSources.getRequiredSourcesQName());
 596             // return null since we cannot find the QName,
 597             // this capability will be removed from required sources and not reported as unresolved-capability
 598             return null;
 599         }
 600     }
 601 }