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.netconf.api.NetconfMessage;
  40 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  41 import org.opendaylight.netconf.sal.connect.api.DeviceActionFactory;
  42 import org.opendaylight.netconf.sal.connect.api.MessageTransformer;
  43 import org.opendaylight.netconf.sal.connect.api.NetconfDeviceSchemasResolver;
  44 import org.opendaylight.netconf.sal.connect.api.RemoteDevice;
  45 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceCommunicator;
  46 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceHandler;
  47 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceServices;
  48 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceServices.Rpcs;
  49 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfDeviceCapabilities;
  50 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfDeviceCommunicator;
  51 import org.opendaylight.netconf.sal.connect.netconf.listener.NetconfSessionPreferences;
  52 import org.opendaylight.netconf.sal.connect.netconf.sal.NetconfDeviceRpc;
  53 import org.opendaylight.netconf.sal.connect.netconf.schema.mapping.BaseNetconfSchemas;
  54 import org.opendaylight.netconf.sal.connect.netconf.schema.mapping.BaseSchema;
  55 import org.opendaylight.netconf.sal.connect.netconf.schema.mapping.NetconfMessageTransformer;
  56 import org.opendaylight.netconf.sal.connect.netconf.util.NetconfMessageTransformUtil;
  57 import org.opendaylight.netconf.sal.connect.util.RemoteDeviceId;
  58 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfCapabilityChange;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.available.capabilities.AvailableCapability;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.available.capabilities.AvailableCapabilityBuilder;
  61 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.unavailable.capabilities.UnavailableCapability;
  62 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.connection.status.unavailable.capabilities.UnavailableCapability.FailureReason;
  63 import org.opendaylight.yangtools.concepts.Registration;
  64 import org.opendaylight.yangtools.rfc8528.data.api.MountPointContext;
  65 import org.opendaylight.yangtools.rfc8528.data.util.EmptyMountPointContext;
  66 import org.opendaylight.yangtools.rfc8528.model.api.SchemaMountConstants;
  67 import org.opendaylight.yangtools.yang.common.QName;
  68 import org.opendaylight.yangtools.yang.common.RpcError;
  69 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  70 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  71 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  72 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  73 import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
  74 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  75 import org.opendaylight.yangtools.yang.model.repo.api.EffectiveModelContextFactory;
  76 import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
  77 import org.opendaylight.yangtools.yang.model.repo.api.SchemaRepository;
  78 import org.opendaylight.yangtools.yang.model.repo.api.SchemaResolutionException;
  79 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
  80 import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
  81 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistry;
  82 import org.slf4j.Logger;
  83 import org.slf4j.LoggerFactory;
  84
  85 /**
  86  *  This is a mediator between NetconfDeviceCommunicator and NetconfDeviceSalFacade.
  87  */
  88 public class NetconfDevice implements RemoteDevice<NetconfDeviceCommunicator> {
  89     private static final Logger LOG = LoggerFactory.getLogger(NetconfDevice.class);
  90
  91     private static final QName RFC8528_SCHEMA_MOUNTS_QNAME = QName.create(
  92         SchemaMountConstants.RFC8528_MODULE, "schema-mounts").intern();
  93     private static final YangInstanceIdentifier RFC8528_SCHEMA_MOUNTS = YangInstanceIdentifier.create(
  94         NodeIdentifier.create(RFC8528_SCHEMA_MOUNTS_QNAME));
  95
  96     protected final RemoteDeviceId id;
  97     protected final EffectiveModelContextFactory schemaContextFactory;
  98     protected final SchemaSourceRegistry schemaRegistry;
  99     protected final SchemaRepository schemaRepository;
 100
 101     protected final List<Registration> sourceRegistrations = new ArrayList<>();
 102
 103     private final RemoteDeviceHandler salFacade;
 104     private final ListeningExecutorService processingExecutor;
 105     private final DeviceActionFactory deviceActionFactory;
 106     private final NetconfDeviceSchemasResolver stateSchemasResolver;
 107     private final NotificationHandler notificationHandler;
 108     private final boolean reconnectOnSchemasChange;
 109     private final BaseNetconfSchemas baseSchemas;
 110
 111     @GuardedBy("this")
 112     private boolean connected = false;
 113
 114     // Message transformer is constructed once the schemas are available
 115     private MessageTransformer messageTransformer;
 116
 117     public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final BaseNetconfSchemas baseSchemas,
 118             final RemoteDeviceId id, final RemoteDeviceHandler salFacade,
 119             final ListeningExecutorService globalProcessingExecutor, final boolean reconnectOnSchemasChange) {
 120         this(schemaResourcesDTO, baseSchemas, id, salFacade, globalProcessingExecutor, reconnectOnSchemasChange, null);
 121     }
 122
 123     public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final BaseNetconfSchemas baseSchemas,
 124             final RemoteDeviceId id, final RemoteDeviceHandler salFacade,
 125             final ListeningExecutorService globalProcessingExecutor, final boolean reconnectOnSchemasChange,
 126             final DeviceActionFactory deviceActionFactory) {
 127         this.baseSchemas = requireNonNull(baseSchemas);
 128         this.id = id;
 129         this.reconnectOnSchemasChange = reconnectOnSchemasChange;
 130         this.deviceActionFactory = deviceActionFactory;
 131         schemaRegistry = schemaResourcesDTO.getSchemaRegistry();
 132         schemaRepository = schemaResourcesDTO.getSchemaRepository();
 133         schemaContextFactory = schemaResourcesDTO.getSchemaContextFactory();
 134         this.salFacade = salFacade;
 135         stateSchemasResolver = schemaResourcesDTO.getStateSchemasResolver();
 136         processingExecutor = requireNonNull(globalProcessingExecutor);
 137         notificationHandler = new NotificationHandler(salFacade, id);
 138     }
 139
 140     @Override
 141     public void onRemoteSessionUp(final NetconfSessionPreferences remoteSessionCapabilities,
 142                                   final NetconfDeviceCommunicator listener) {
 143         // SchemaContext setup has to be performed in a dedicated thread since
 144         // we are in a netty thread in this method
 145         // Yang models are being downloaded in this method and it would cause a
 146         // deadlock if we used the netty thread
 147         // http://netty.io/wiki/thread-model.html
 148         setConnected(true);
 149         LOG.debug("{}: Session to remote device established with {}", id, remoteSessionCapabilities);
 150
 151         final BaseSchema baseSchema = resolveBaseSchema(remoteSessionCapabilities.isNotificationsSupported());
 152         final NetconfDeviceRpc initRpc = new NetconfDeviceRpc(baseSchema.getEffectiveModelContext(), listener,
 153             new NetconfMessageTransformer(baseSchema.getMountPointContext(), false, baseSchema));
 154         final ListenableFuture<DeviceSources> sourceResolverFuture = processingExecutor.submit(
 155             new DeviceSourcesResolver(id, baseSchema, initRpc, remoteSessionCapabilities, stateSchemasResolver));
 156
 157         if (shouldListenOnSchemaChange(remoteSessionCapabilities)) {
 158             registerToBaseNetconfStream(initRpc, listener);
 159         }
 160
 161         // Set up the SchemaContext for the device
 162         final ListenableFuture<SchemaResult> futureSchema = Futures.transformAsync(sourceResolverFuture,
 163             deviceSources -> assembleSchemaContext(deviceSources, remoteSessionCapabilities), processingExecutor);
 164
 165         // Potentially acquire mount point list and interpret it
 166         final ListenableFuture<NetconfDeviceSchema> futureContext = Futures.transformAsync(futureSchema,
 167             result -> Futures.transform(createMountPointContext(result.modelContext(), baseSchema, listener),
 168                 mount -> new NetconfDeviceSchema(result.capabilities(), mount), processingExecutor),
 169             processingExecutor);
 170
 171         Futures.addCallback(futureContext, new FutureCallback<>() {
 172             @Override
 173             public void onSuccess(final NetconfDeviceSchema result) {
 174                 handleSalInitializationSuccess(result, remoteSessionCapabilities,
 175                         getDeviceSpecificRpc(result.mountContext(), listener, baseSchema), listener);
 176             }
 177
 178             @Override
 179             public void onFailure(final Throwable cause) {
 180                 LOG.warn("{}: Unexpected error resolving device sources", id, cause);
 181                 // FIXME: this causes salFacade to see onDeviceDisconnected() and then onDeviceFailed(), which is quite
 182                 //        weird
 183                 handleSalInitializationFailure(cause, listener);
 184                 salFacade.onDeviceFailed(cause);
 185             }
 186         }, MoreExecutors.directExecutor());
 187     }
 188
 189     private void registerToBaseNetconfStream(final NetconfDeviceRpc deviceRpc,
 190                                              final NetconfDeviceCommunicator listener) {
 191         // TODO check whether the model describing create subscription is present in schema
 192         // Perhaps add a default schema context to support create-subscription if the model was not provided
 193         // (same as what we do for base netconf operations in transformer)
 194         final ListenableFuture<DOMRpcResult> rpcResultListenableFuture = deviceRpc.invokeRpc(
 195                 NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_QNAME,
 196                 NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_CONTENT);
 197
 198         Futures.addCallback(rpcResultListenableFuture, new FutureCallback<DOMRpcResult>() {
 199             @Override
 200             public void onSuccess(final DOMRpcResult domRpcResult) {
 201                 notificationHandler.addNotificationFilter(notification -> {
 202                     if (NetconfCapabilityChange.QNAME.equals(notification.getBody().getIdentifier().getNodeType())) {
 203                         LOG.info("{}: Schemas change detected, reconnecting", id);
 204                         // Only disconnect is enough,
 205                         // the reconnecting nature of the connector will take care of reconnecting
 206                         listener.disconnect();
 207                         return false;
 208                     }
 209                     return true;
 210                 });
 211             }
 212
 213             @Override
 214             public void onFailure(final Throwable throwable) {
 215                 LOG.warn("Unable to subscribe to base notification stream. Schemas will not be reloaded on the fly",
 216                         throwable);
 217             }
 218         }, MoreExecutors.directExecutor());
 219     }
 220
 221     private boolean shouldListenOnSchemaChange(final NetconfSessionPreferences remoteSessionCapabilities) {
 222         return remoteSessionCapabilities.isNotificationsSupported() && reconnectOnSchemasChange;
 223     }
 224
 225     private synchronized void handleSalInitializationSuccess(final NetconfDeviceSchema deviceSchema,
 226             final NetconfSessionPreferences remoteSessionCapabilities, final Rpcs deviceRpc,
 227             final RemoteDeviceCommunicator listener) {
 228         //NetconfDevice.SchemaSetup can complete after NetconfDeviceCommunicator was closed. In that case do nothing,
 229         //since salFacade.onDeviceDisconnected was already called.
 230         if (connected) {
 231             final var mount = deviceSchema.mountContext();
 232             messageTransformer = new NetconfMessageTransformer(mount, true,
 233                 resolveBaseSchema(remoteSessionCapabilities.isNotificationsSupported()));
 234
 235             // salFacade.onDeviceConnected has to be called before the notification handler is initialized
 236             salFacade.onDeviceConnected(deviceSchema, remoteSessionCapabilities,
 237                 new RemoteDeviceServices(deviceRpc, deviceActionFactory == null ? null
 238                     : deviceActionFactory.createDeviceAction(messageTransformer, listener)));
 239             notificationHandler.onRemoteSchemaUp(messageTransformer);
 240
 241             LOG.info("{}: Netconf connector initialized successfully", id);
 242         } else {
 243             LOG.warn("{}: Device communicator was closed before schema setup finished.", id);
 244         }
 245     }
 246
 247     private void handleSalInitializationFailure(final Throwable throwable, final RemoteDeviceCommunicator listener) {
 248         LOG.error("{}: Initialization in sal failed, disconnecting from device", id, throwable);
 249         listener.close();
 250         onRemoteSessionDown();
 251         resetMessageTransformer();
 252     }
 253
 254     /**
 255      * Set the transformer to null as is in initial state.
 256      */
 257     private void resetMessageTransformer() {
 258         updateTransformer(null);
 259     }
 260
 261     private synchronized void updateTransformer(final MessageTransformer transformer) {
 262         messageTransformer = transformer;
 263     }
 264
 265     private synchronized void setConnected(final boolean connected) {
 266         this.connected = connected;
 267     }
 268
 269     private ListenableFuture<SchemaResult> assembleSchemaContext(final DeviceSources deviceSources,
 270             final NetconfSessionPreferences remoteSessionCapabilities) {
 271         LOG.debug("{}: Resolved device sources to {}", id, deviceSources);
 272
 273         sourceRegistrations.addAll(deviceSources.register(schemaRegistry));
 274
 275         return new SchemaSetup(deviceSources, remoteSessionCapabilities).startResolution();
 276     }
 277
 278     private ListenableFuture<@NonNull MountPointContext> createMountPointContext(
 279             final EffectiveModelContext schemaContext, final BaseSchema baseSchema,
 280             final NetconfDeviceCommunicator listener) {
 281         final MountPointContext emptyContext = new EmptyMountPointContext(schemaContext);
 282         if (schemaContext.findModule(SchemaMountConstants.RFC8528_MODULE).isEmpty()) {
 283             return Futures.immediateFuture(emptyContext);
 284         }
 285
 286         // Create a temporary RPC invoker and acquire the mount point tree
 287         LOG.debug("{}: Acquiring available mount points", id);
 288         final NetconfDeviceRpc deviceRpc = new NetconfDeviceRpc(schemaContext, listener,
 289             new NetconfMessageTransformer(emptyContext, false, baseSchema));
 290
 291         return Futures.transform(deviceRpc.invokeRpc(NetconfMessageTransformUtil.NETCONF_GET_QNAME,
 292             Builders.containerBuilder().withNodeIdentifier(NETCONF_GET_NODEID)
 293                 .withChild(NetconfMessageTransformUtil.toFilterStructure(RFC8528_SCHEMA_MOUNTS, schemaContext))
 294                 .build()), rpcResult -> processSchemaMounts(rpcResult, emptyContext), MoreExecutors.directExecutor());
 295     }
 296
 297     private MountPointContext processSchemaMounts(final DOMRpcResult rpcResult, final MountPointContext emptyContext) {
 298         final Collection<? extends RpcError> errors = rpcResult.getErrors();
 299         if (!errors.isEmpty()) {
 300             LOG.warn("{}: Schema-mounts acquisition resulted in errors {}", id, errors);
 301         }
 302         final NormalizedNode schemaMounts = rpcResult.getResult();
 303         if (schemaMounts == null) {
 304             LOG.debug("{}: device does not define any schema mounts", id);
 305             return emptyContext;
 306         }
 307         if (!(schemaMounts instanceof ContainerNode)) {
 308             LOG.warn("{}: ignoring non-container schema mounts {}", id, schemaMounts);
 309             return emptyContext;
 310         }
 311
 312         return DeviceMountPointContext.create(emptyContext, (ContainerNode) schemaMounts);
 313     }
 314
 315     @Override
 316     public void onRemoteSessionDown() {
 317         setConnected(false);
 318         notificationHandler.onRemoteSchemaDown();
 319
 320         salFacade.onDeviceDisconnected();
 321         sourceRegistrations.forEach(Registration::close);
 322         sourceRegistrations.clear();
 323         resetMessageTransformer();
 324     }
 325
 326     @Override
 327     public void onRemoteSessionFailed(final Throwable throwable) {
 328         setConnected(false);
 329         salFacade.onDeviceFailed(throwable);
 330     }
 331
 332     @Override
 333     public void onNotification(final NetconfMessage notification) {
 334         notificationHandler.handleNotification(notification);
 335     }
 336
 337     private BaseSchema resolveBaseSchema(final boolean notificationSupport) {
 338         return notificationSupport ? baseSchemas.getBaseSchemaWithNotifications() : baseSchemas.getBaseSchema();
 339     }
 340
 341     protected NetconfDeviceRpc getDeviceSpecificRpc(final MountPointContext result,
 342             final RemoteDeviceCommunicator listener, final BaseSchema schema) {
 343         return new NetconfDeviceRpc(result.getEffectiveModelContext(), listener,
 344             new NetconfMessageTransformer(result, true, schema));
 345     }
 346
 347     /**
 348      * Just a transfer object containing schema related dependencies. Injected in constructor.
 349      */
 350     public static class SchemaResourcesDTO {
 351         private final SchemaSourceRegistry schemaRegistry;
 352         private final SchemaRepository schemaRepository;
 353         private final EffectiveModelContextFactory schemaContextFactory;
 354         private final NetconfDeviceSchemasResolver stateSchemasResolver;
 355
 356         public SchemaResourcesDTO(final SchemaSourceRegistry schemaRegistry,
 357                                   final SchemaRepository schemaRepository,
 358                                   final EffectiveModelContextFactory schemaContextFactory,
 359                                   final NetconfDeviceSchemasResolver deviceSchemasResolver) {
 360             this.schemaRegistry = requireNonNull(schemaRegistry);
 361             this.schemaRepository = requireNonNull(schemaRepository);
 362             this.schemaContextFactory = requireNonNull(schemaContextFactory);
 363             stateSchemasResolver = requireNonNull(deviceSchemasResolver);
 364         }
 365
 366         public SchemaSourceRegistry getSchemaRegistry() {
 367             return schemaRegistry;
 368         }
 369
 370         public SchemaRepository getSchemaRepository() {
 371             return schemaRepository;
 372         }
 373
 374         public EffectiveModelContextFactory getSchemaContextFactory() {
 375             return schemaContextFactory;
 376         }
 377
 378         public NetconfDeviceSchemasResolver getStateSchemasResolver() {
 379             return stateSchemasResolver;
 380         }
 381     }
 382
 383     /**
 384      * A dedicated exception to indicate when we fail to setup an {@link EffectiveModelContext}.
 385      */
 386     public static final class EmptySchemaContextException extends Exception {
 387         private static final long serialVersionUID = 1L;
 388
 389         public EmptySchemaContextException(final String message) {
 390             super(message);
 391         }
 392     }
 393
 394     /**
 395      * {@link NetconfDeviceCapabilities} and {@link EffectiveModelContext}.
 396      */
 397     private record SchemaResult(
 398         @NonNull NetconfDeviceCapabilities capabilities,
 399         @NonNull EffectiveModelContext modelContext) {
 400
 401         SchemaResult {
 402             requireNonNull(capabilities);
 403             requireNonNull(modelContext);
 404         }
 405     }
 406
 407     /**
 408      * Schema builder that tries to build schema context from provided sources or biggest subset of it.
 409      */
 410     private final class SchemaSetup implements FutureCallback<EffectiveModelContext> {
 411         private final SettableFuture<SchemaResult> resultFuture = SettableFuture.create();
 412
 413         private final Set<AvailableCapability> nonModuleBasedCapabilities = new HashSet<>();
 414         private final Map<QName, FailureReason> unresolvedCapabilites = new HashMap<>();
 415         private final Set<AvailableCapability> resolvedCapabilities = new HashSet<>();
 416
 417         private final DeviceSources deviceSources;
 418         private final NetconfSessionPreferences remoteSessionCapabilities;
 419
 420         private Collection<SourceIdentifier> requiredSources;
 421
 422         SchemaSetup(final DeviceSources deviceSources, final NetconfSessionPreferences remoteSessionCapabilities) {
 423             this.deviceSources = deviceSources;
 424             this.remoteSessionCapabilities = remoteSessionCapabilities;
 425
 426             // If device supports notifications and does not contain necessary modules, add them automatically
 427             if (remoteSessionCapabilities.containsNonModuleCapability(
 428                     XmlNetconfConstants.URN_IETF_PARAMS_NETCONF_CAPABILITY_NOTIFICATION_1_0)) {
 429                 deviceSources.getRequiredSourcesQName().addAll(
 430                         Arrays.asList(
 431                                 org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.notification._1._0.rev080714
 432                                         .$YangModuleInfoImpl.getInstance().getName(),
 433                                 org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.yang.types.rev130715
 434                                         .$YangModuleInfoImpl.getInstance().getName()
 435                         )
 436                 );
 437             }
 438
 439             requiredSources = deviceSources.getRequiredSources();
 440             final Collection<SourceIdentifier> missingSources = filterMissingSources(requiredSources);
 441
 442             addUnresolvedCapabilities(getQNameFromSourceIdentifiers(missingSources),
 443                 UnavailableCapability.FailureReason.MissingSource);
 444             requiredSources.removeAll(missingSources);
 445         }
 446
 447         ListenableFuture<SchemaResult> startResolution() {
 448             trySetupSchema();
 449             return resultFuture;
 450         }
 451
 452         @Override
 453         public void onSuccess(final EffectiveModelContext result) {
 454             LOG.debug("{}: Schema context built successfully from {}", id, requiredSources);
 455
 456             final Collection<QName> filteredQNames = Sets.difference(deviceSources.getRequiredSourcesQName(),
 457                     unresolvedCapabilites.keySet());
 458             resolvedCapabilities.addAll(filteredQNames.stream()
 459                 .map(capability -> new AvailableCapabilityBuilder()
 460                     .setCapability(capability.toString())
 461                     .setCapabilityOrigin(remoteSessionCapabilities.capabilityOrigin(capability))
 462                     .build())
 463                 .collect(Collectors.toList()));
 464
 465             nonModuleBasedCapabilities.addAll(remoteSessionCapabilities.nonModuleCaps().keySet().stream()
 466                 .map(capability -> new AvailableCapabilityBuilder()
 467                     .setCapability(capability)
 468                     .setCapabilityOrigin(remoteSessionCapabilities.capabilityOrigin(capability))
 469                     .build())
 470                 .collect(Collectors.toList()));
 471
 472
 473             resultFuture.set(new SchemaResult(new NetconfDeviceCapabilities(ImmutableMap.copyOf(unresolvedCapabilites),
 474                 ImmutableSet.copyOf(resolvedCapabilities), ImmutableSet.copyOf(nonModuleBasedCapabilities)), result));
 475         }
 476
 477         @Override
 478         public void onFailure(final Throwable cause) {
 479             // schemaBuilderFuture.checkedGet() throws only SchemaResolutionException
 480             // that might be wrapping a MissingSchemaSourceException so we need to look
 481             // at the cause of the exception to make sure we don't misinterpret it.
 482             if (cause instanceof MissingSchemaSourceException) {
 483                 requiredSources = handleMissingSchemaSourceException((MissingSchemaSourceException) cause);
 484             } else if (cause instanceof SchemaResolutionException) {
 485                 requiredSources = handleSchemaResolutionException((SchemaResolutionException) cause);
 486             } else {
 487                 LOG.debug("Unhandled failure", cause);
 488                 resultFuture.setException(cause);
 489                 // No more trying...
 490                 return;
 491             }
 492
 493             trySetupSchema();
 494         }
 495
 496         private void trySetupSchema() {
 497             if (!requiredSources.isEmpty()) {
 498                 // Initiate async resolution, drive it back based on the result
 499                 LOG.trace("{}: Trying to build schema context from {}", id, requiredSources);
 500                 Futures.addCallback(schemaContextFactory.createEffectiveModelContext(requiredSources), this,
 501                     MoreExecutors.directExecutor());
 502             } else {
 503                 LOG.debug("{}: no more sources for schema context", id);
 504                 resultFuture.setException(new EmptySchemaContextException(id + ": No more sources for schema context"));
 505             }
 506         }
 507
 508         private List<SourceIdentifier> filterMissingSources(final Collection<SourceIdentifier> origSources) {
 509             return origSources.parallelStream().filter(sourceIdentifier -> {
 510                 try {
 511                     schemaRepository.getSchemaSource(sourceIdentifier, YangTextSchemaSource.class).get();
 512                     return false;
 513                 } catch (InterruptedException | ExecutionException e) {
 514                     return true;
 515                 }
 516             }).collect(Collectors.toList());
 517         }
 518
 519         private void addUnresolvedCapabilities(final Collection<QName> capabilities, final FailureReason reason) {
 520             for (QName s : capabilities) {
 521                 unresolvedCapabilites.put(s, reason);
 522             }
 523         }
 524
 525         private List<SourceIdentifier> handleMissingSchemaSourceException(
 526                 final MissingSchemaSourceException exception) {
 527             // In case source missing, try without it
 528             final SourceIdentifier missingSource = exception.getSourceId();
 529             LOG.warn("{}: Unable to build schema context, missing source {}, will reattempt without it",
 530                 id, missingSource);
 531             LOG.debug("{}: Unable to build schema context, missing source {}, will reattempt without it",
 532                 id, missingSource, exception);
 533             final var qNameOfMissingSource = getQNameFromSourceIdentifiers(Sets.newHashSet(missingSource));
 534             if (!qNameOfMissingSource.isEmpty()) {
 535                 addUnresolvedCapabilities(qNameOfMissingSource, UnavailableCapability.FailureReason.MissingSource);
 536             }
 537             return stripUnavailableSource(missingSource);
 538         }
 539
 540         private Collection<SourceIdentifier> handleSchemaResolutionException(
 541                 final SchemaResolutionException resolutionException) {
 542             // In case resolution error, try only with resolved sources
 543             // There are two options why schema resolution exception occurred : unsatisfied imports or flawed model
 544             // FIXME Do we really have assurance that these two cases cannot happen at once?
 545             if (resolutionException.getFailedSource() != null) {
 546                 // flawed model - exclude it
 547                 final SourceIdentifier failedSourceId = resolutionException.getFailedSource();
 548                 LOG.warn("{}: Unable to build schema context, failed to resolve source {}, will reattempt without it",
 549                     id, failedSourceId);
 550                 LOG.warn("{}: Unable to build schema context, failed to resolve source {}, will reattempt without it",
 551                     id, failedSourceId, resolutionException);
 552                 addUnresolvedCapabilities(getQNameFromSourceIdentifiers(List.of(failedSourceId)),
 553                         UnavailableCapability.FailureReason.UnableToResolve);
 554                 return stripUnavailableSource(resolutionException.getFailedSource());
 555             }
 556             // unsatisfied imports
 557             addUnresolvedCapabilities(
 558                 getQNameFromSourceIdentifiers(resolutionException.getUnsatisfiedImports().keySet()),
 559                 UnavailableCapability.FailureReason.UnableToResolve);
 560             LOG.warn("{}: Unable to build schema context, unsatisfied imports {}, will reattempt with resolved only",
 561                 id, resolutionException.getUnsatisfiedImports());
 562             LOG.debug("{}: Unable to build schema context, unsatisfied imports {}, will reattempt with resolved only",
 563                 id, resolutionException.getUnsatisfiedImports(), resolutionException);
 564             return resolutionException.getResolvedSources();
 565         }
 566
 567         private List<SourceIdentifier> stripUnavailableSource(final SourceIdentifier sourceIdToRemove) {
 568             final var tmp = new ArrayList<>(requiredSources);
 569             checkState(tmp.remove(sourceIdToRemove), "%s: Trying to remove %s from %s failed", id, sourceIdToRemove,
 570                 requiredSources);
 571             return tmp;
 572         }
 573
 574         private Collection<QName> getQNameFromSourceIdentifiers(final Collection<SourceIdentifier> identifiers) {
 575             final Collection<QName> qNames = Collections2.transform(identifiers, this::getQNameFromSourceIdentifier);
 576
 577             if (qNames.isEmpty()) {
 578                 LOG.debug("{}: Unable to map any source identifiers to a capability reported by device : {}", id,
 579                         identifiers);
 580             }
 581             return Collections2.filter(qNames, Predicates.notNull());
 582         }
 583
 584         private QName getQNameFromSourceIdentifier(final SourceIdentifier identifier) {
 585             // Required sources are all required and provided merged in DeviceSourcesResolver
 586             for (final QName qname : deviceSources.getRequiredSourcesQName()) {
 587                 if (!qname.getLocalName().equals(identifier.name().getLocalName())) {
 588                     continue;
 589                 }
 590
 591                 if (Objects.equals(identifier.revision(), qname.getRevision().orElse(null))) {
 592                     return qname;
 593                 }
 594             }
 595             LOG.warn("Unable to map identifier to a devices reported capability: {} Available: {}",identifier,
 596                     deviceSources.getRequiredSourcesQName());
 597             // return null since we cannot find the QName,
 598             // this capability will be removed from required sources and not reported as unresolved-capability
 599             return null;
 600         }
 601     }
 602 }