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.NetconfDeviceSchemasResolver;
  43 import org.opendaylight.netconf.sal.connect.api.RemoteDevice;
  44 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceCommunicator;
  45 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceHandler;
  46 import org.opendaylight.netconf.sal.connect.api.RemoteDeviceId;
  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.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfCapabilityChange;
  58 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.device.rev221225.connection.oper.available.capabilities.AvailableCapability;
  59 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.device.rev221225.connection.oper.available.capabilities.AvailableCapabilityBuilder;
  60 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.device.rev221225.connection.oper.unavailable.capabilities.UnavailableCapability;
  61 import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.device.rev221225.connection.oper.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.data.api.YangInstanceIdentifier;
  68 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  69 import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
  70 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  71 import org.opendaylight.yangtools.yang.model.repo.api.EffectiveModelContextFactory;
  72 import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
  73 import org.opendaylight.yangtools.yang.model.repo.api.SchemaRepository;
  74 import org.opendaylight.yangtools.yang.model.repo.api.SchemaResolutionException;
  75 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
  76 import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
  77 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistry;
  78 import org.slf4j.Logger;
  79 import org.slf4j.LoggerFactory;
  80
  81 /**
  82  *  This is a mediator between NetconfDeviceCommunicator and NetconfDeviceSalFacade.
  83  */
  84 public class NetconfDevice implements RemoteDevice<NetconfDeviceCommunicator> {
  85     private static final Logger LOG = LoggerFactory.getLogger(NetconfDevice.class);
  86
  87     private static final QName RFC8528_SCHEMA_MOUNTS_QNAME = QName.create(
  88         SchemaMountConstants.RFC8528_MODULE, "schema-mounts").intern();
  89     private static final YangInstanceIdentifier RFC8528_SCHEMA_MOUNTS = YangInstanceIdentifier.create(
  90         NodeIdentifier.create(RFC8528_SCHEMA_MOUNTS_QNAME));
  91
  92     protected final RemoteDeviceId id;
  93     protected final EffectiveModelContextFactory schemaContextFactory;
  94     protected final SchemaSourceRegistry schemaRegistry;
  95     protected final SchemaRepository schemaRepository;
  96
  97     protected final List<Registration> sourceRegistrations = new ArrayList<>();
  98
  99     private final RemoteDeviceHandler salFacade;
 100     private final ListeningExecutorService processingExecutor;
 101     private final DeviceActionFactory deviceActionFactory;
 102     private final NetconfDeviceSchemasResolver stateSchemasResolver;
 103     private final NotificationHandler notificationHandler;
 104     private final boolean reconnectOnSchemasChange;
 105     private final BaseNetconfSchemas baseSchemas;
 106
 107     @GuardedBy("this")
 108     private boolean connected = false;
 109
 110     // Message transformer is constructed once the schemas are available
 111     private NetconfMessageTransformer messageTransformer;
 112
 113     public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final BaseNetconfSchemas baseSchemas,
 114             final RemoteDeviceId id, final RemoteDeviceHandler salFacade,
 115             final ListeningExecutorService globalProcessingExecutor, final boolean reconnectOnSchemasChange) {
 116         this(schemaResourcesDTO, baseSchemas, id, salFacade, globalProcessingExecutor, reconnectOnSchemasChange, null);
 117     }
 118
 119     public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final BaseNetconfSchemas baseSchemas,
 120             final RemoteDeviceId id, final RemoteDeviceHandler salFacade,
 121             final ListeningExecutorService globalProcessingExecutor, final boolean reconnectOnSchemasChange,
 122             final DeviceActionFactory deviceActionFactory) {
 123         this.baseSchemas = requireNonNull(baseSchemas);
 124         this.id = id;
 125         this.reconnectOnSchemasChange = reconnectOnSchemasChange;
 126         this.deviceActionFactory = deviceActionFactory;
 127         schemaRegistry = schemaResourcesDTO.getSchemaRegistry();
 128         schemaRepository = schemaResourcesDTO.getSchemaRepository();
 129         schemaContextFactory = schemaResourcesDTO.getSchemaContextFactory();
 130         this.salFacade = salFacade;
 131         stateSchemasResolver = schemaResourcesDTO.getStateSchemasResolver();
 132         processingExecutor = requireNonNull(globalProcessingExecutor);
 133         notificationHandler = new NotificationHandler(salFacade, id);
 134     }
 135
 136     @Override
 137     public void onRemoteSessionUp(final NetconfSessionPreferences remoteSessionCapabilities,
 138                                   final NetconfDeviceCommunicator listener) {
 139         // SchemaContext setup has to be performed in a dedicated thread since
 140         // we are in a netty thread in this method
 141         // Yang models are being downloaded in this method and it would cause a
 142         // deadlock if we used the netty thread
 143         // http://netty.io/wiki/thread-model.html
 144         setConnected(true);
 145         LOG.debug("{}: Session to remote device established with {}", id, remoteSessionCapabilities);
 146
 147         final BaseSchema baseSchema = resolveBaseSchema(remoteSessionCapabilities.isNotificationsSupported());
 148         final NetconfDeviceRpc initRpc = new NetconfDeviceRpc(baseSchema.getEffectiveModelContext(), listener,
 149             new NetconfMessageTransformer(baseSchema.getMountPointContext(), false, baseSchema));
 150         final ListenableFuture<DeviceSources> sourceResolverFuture = processingExecutor.submit(
 151             new DeviceSourcesResolver(id, baseSchema, initRpc, remoteSessionCapabilities, stateSchemasResolver));
 152
 153         if (shouldListenOnSchemaChange(remoteSessionCapabilities)) {
 154             registerToBaseNetconfStream(initRpc, listener);
 155         }
 156
 157         // Set up the SchemaContext for the device
 158         final ListenableFuture<SchemaResult> futureSchema = Futures.transformAsync(sourceResolverFuture,
 159             deviceSources -> assembleSchemaContext(deviceSources, remoteSessionCapabilities), processingExecutor);
 160
 161         // Potentially acquire mount point list and interpret it
 162         final ListenableFuture<NetconfDeviceSchema> futureContext = Futures.transformAsync(futureSchema,
 163             result -> Futures.transform(createMountPointContext(result.modelContext(), baseSchema, listener),
 164                 mount -> new NetconfDeviceSchema(result.capabilities(), mount), processingExecutor),
 165             processingExecutor);
 166
 167         Futures.addCallback(futureContext, new FutureCallback<>() {
 168             @Override
 169             public void onSuccess(final NetconfDeviceSchema result) {
 170                 handleSalInitializationSuccess(result, remoteSessionCapabilities,
 171                         getDeviceSpecificRpc(result.mountContext(), listener, baseSchema), listener);
 172             }
 173
 174             @Override
 175             public void onFailure(final Throwable cause) {
 176                 LOG.warn("{}: Unexpected error resolving device sources", id, cause);
 177                 // FIXME: this causes salFacade to see onDeviceDisconnected() and then onDeviceFailed(), which is quite
 178                 //        weird
 179                 handleSalInitializationFailure(cause, listener);
 180                 salFacade.onDeviceFailed(cause);
 181             }
 182         }, MoreExecutors.directExecutor());
 183     }
 184
 185     private void registerToBaseNetconfStream(final NetconfDeviceRpc deviceRpc,
 186                                              final NetconfDeviceCommunicator listener) {
 187         // TODO check whether the model describing create subscription is present in schema
 188         // Perhaps add a default schema context to support create-subscription if the model was not provided
 189         // (same as what we do for base netconf operations in transformer)
 190         final var rpcResultListenableFuture = deviceRpc.invokeRpc(
 191                 NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_QNAME,
 192                 NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_CONTENT);
 193
 194         Futures.addCallback(rpcResultListenableFuture, new FutureCallback<DOMRpcResult>() {
 195             @Override
 196             public void onSuccess(final DOMRpcResult domRpcResult) {
 197                 notificationHandler.addNotificationFilter(notification -> {
 198                     if (NetconfCapabilityChange.QNAME.equals(notification.getBody().getIdentifier().getNodeType())) {
 199                         LOG.info("{}: Schemas change detected, reconnecting", id);
 200                         // Only disconnect is enough,
 201                         // the reconnecting nature of the connector will take care of reconnecting
 202                         listener.disconnect();
 203                         return false;
 204                     }
 205                     return true;
 206                 });
 207             }
 208
 209             @Override
 210             public void onFailure(final Throwable throwable) {
 211                 LOG.warn("Unable to subscribe to base notification stream. Schemas will not be reloaded on the fly",
 212                         throwable);
 213             }
 214         }, MoreExecutors.directExecutor());
 215     }
 216
 217     private boolean shouldListenOnSchemaChange(final NetconfSessionPreferences remoteSessionCapabilities) {
 218         return remoteSessionCapabilities.isNotificationsSupported() && reconnectOnSchemasChange;
 219     }
 220
 221     private synchronized void handleSalInitializationSuccess(final NetconfDeviceSchema deviceSchema,
 222             final NetconfSessionPreferences remoteSessionCapabilities, final Rpcs deviceRpc,
 223             final RemoteDeviceCommunicator listener) {
 224         //NetconfDevice.SchemaSetup can complete after NetconfDeviceCommunicator was closed. In that case do nothing,
 225         //since salFacade.onDeviceDisconnected was already called.
 226         if (connected) {
 227             final var mount = deviceSchema.mountContext();
 228             messageTransformer = new NetconfMessageTransformer(mount, true,
 229                 resolveBaseSchema(remoteSessionCapabilities.isNotificationsSupported()));
 230
 231             // salFacade.onDeviceConnected has to be called before the notification handler is initialized
 232             salFacade.onDeviceConnected(deviceSchema, remoteSessionCapabilities,
 233                 new RemoteDeviceServices(deviceRpc, deviceActionFactory == null ? null
 234                     : deviceActionFactory.createDeviceAction(messageTransformer, listener)));
 235             notificationHandler.onRemoteSchemaUp(messageTransformer);
 236
 237             LOG.info("{}: Netconf connector initialized successfully", id);
 238         } else {
 239             LOG.warn("{}: Device communicator was closed before schema setup finished.", id);
 240         }
 241     }
 242
 243     private void handleSalInitializationFailure(final Throwable throwable, final RemoteDeviceCommunicator listener) {
 244         LOG.error("{}: Initialization in sal failed, disconnecting from device", id, throwable);
 245         listener.close();
 246         onRemoteSessionDown();
 247         resetMessageTransformer();
 248     }
 249
 250     /**
 251      * Set the transformer to null as is in initial state.
 252      */
 253     private void resetMessageTransformer() {
 254         updateTransformer(null);
 255     }
 256
 257     private synchronized void updateTransformer(final NetconfMessageTransformer transformer) {
 258         messageTransformer = transformer;
 259     }
 260
 261     private synchronized void setConnected(final boolean connected) {
 262         this.connected = connected;
 263     }
 264
 265     private ListenableFuture<SchemaResult> assembleSchemaContext(final DeviceSources deviceSources,
 266             final NetconfSessionPreferences remoteSessionCapabilities) {
 267         LOG.debug("{}: Resolved device sources to {}", id, deviceSources);
 268
 269         sourceRegistrations.addAll(deviceSources.register(schemaRegistry));
 270
 271         return new SchemaSetup(deviceSources, remoteSessionCapabilities).startResolution();
 272     }
 273
 274     private ListenableFuture<@NonNull MountPointContext> createMountPointContext(
 275             final EffectiveModelContext schemaContext, final BaseSchema baseSchema,
 276             final NetconfDeviceCommunicator listener) {
 277         final MountPointContext emptyContext = new EmptyMountPointContext(schemaContext);
 278         if (schemaContext.findModule(SchemaMountConstants.RFC8528_MODULE).isEmpty()) {
 279             return Futures.immediateFuture(emptyContext);
 280         }
 281
 282         // Create a temporary RPC invoker and acquire the mount point tree
 283         LOG.debug("{}: Acquiring available mount points", id);
 284         final NetconfDeviceRpc deviceRpc = new NetconfDeviceRpc(schemaContext, listener,
 285             new NetconfMessageTransformer(emptyContext, false, baseSchema));
 286
 287         return Futures.transform(deviceRpc.invokeRpc(NetconfMessageTransformUtil.NETCONF_GET_QNAME,
 288             Builders.containerBuilder().withNodeIdentifier(NETCONF_GET_NODEID)
 289                 .withChild(NetconfMessageTransformUtil.toFilterStructure(RFC8528_SCHEMA_MOUNTS, schemaContext))
 290                 .build()), rpcResult -> processSchemaMounts(rpcResult, emptyContext), MoreExecutors.directExecutor());
 291     }
 292
 293     private MountPointContext processSchemaMounts(final DOMRpcResult rpcResult, final MountPointContext emptyContext) {
 294         final var errors = rpcResult.errors();
 295         if (!errors.isEmpty()) {
 296             LOG.warn("{}: Schema-mounts acquisition resulted in errors {}", id, errors);
 297         }
 298         final var schemaMounts = rpcResult.value();
 299         if (schemaMounts == null) {
 300             LOG.debug("{}: device does not define any schema mounts", id);
 301             return emptyContext;
 302         }
 303
 304         return DeviceMountPointContext.create(emptyContext, schemaMounts);
 305     }
 306
 307     @Override
 308     public void onRemoteSessionDown() {
 309         setConnected(false);
 310         notificationHandler.onRemoteSchemaDown();
 311
 312         salFacade.onDeviceDisconnected();
 313         sourceRegistrations.forEach(Registration::close);
 314         sourceRegistrations.clear();
 315         resetMessageTransformer();
 316     }
 317
 318     @Override
 319     public void onRemoteSessionFailed(final Throwable throwable) {
 320         setConnected(false);
 321         salFacade.onDeviceFailed(throwable);
 322     }
 323
 324     @Override
 325     public void onNotification(final NetconfMessage notification) {
 326         notificationHandler.handleNotification(notification);
 327     }
 328
 329     private BaseSchema resolveBaseSchema(final boolean notificationSupport) {
 330         return notificationSupport ? baseSchemas.getBaseSchemaWithNotifications() : baseSchemas.getBaseSchema();
 331     }
 332
 333     protected NetconfDeviceRpc getDeviceSpecificRpc(final MountPointContext result,
 334             final RemoteDeviceCommunicator listener, final BaseSchema schema) {
 335         return new NetconfDeviceRpc(result.getEffectiveModelContext(), listener,
 336             new NetconfMessageTransformer(result, true, schema));
 337     }
 338
 339     /**
 340      * Just a transfer object containing schema related dependencies. Injected in constructor.
 341      */
 342     public static class SchemaResourcesDTO {
 343         private final SchemaSourceRegistry schemaRegistry;
 344         private final SchemaRepository schemaRepository;
 345         private final EffectiveModelContextFactory schemaContextFactory;
 346         private final NetconfDeviceSchemasResolver stateSchemasResolver;
 347
 348         public SchemaResourcesDTO(final SchemaSourceRegistry schemaRegistry,
 349                                   final SchemaRepository schemaRepository,
 350                                   final EffectiveModelContextFactory schemaContextFactory,
 351                                   final NetconfDeviceSchemasResolver deviceSchemasResolver) {
 352             this.schemaRegistry = requireNonNull(schemaRegistry);
 353             this.schemaRepository = requireNonNull(schemaRepository);
 354             this.schemaContextFactory = requireNonNull(schemaContextFactory);
 355             stateSchemasResolver = requireNonNull(deviceSchemasResolver);
 356         }
 357
 358         public SchemaSourceRegistry getSchemaRegistry() {
 359             return schemaRegistry;
 360         }
 361
 362         public SchemaRepository getSchemaRepository() {
 363             return schemaRepository;
 364         }
 365
 366         public EffectiveModelContextFactory getSchemaContextFactory() {
 367             return schemaContextFactory;
 368         }
 369
 370         public NetconfDeviceSchemasResolver getStateSchemasResolver() {
 371             return stateSchemasResolver;
 372         }
 373     }
 374
 375     /**
 376      * A dedicated exception to indicate when we fail to setup an {@link EffectiveModelContext}.
 377      */
 378     public static final class EmptySchemaContextException extends Exception {
 379         private static final long serialVersionUID = 1L;
 380
 381         public EmptySchemaContextException(final String message) {
 382             super(message);
 383         }
 384     }
 385
 386     /**
 387      * {@link NetconfDeviceCapabilities} and {@link EffectiveModelContext}.
 388      */
 389     private record SchemaResult(
 390         @NonNull NetconfDeviceCapabilities capabilities,
 391         @NonNull EffectiveModelContext modelContext) {
 392
 393         SchemaResult {
 394             requireNonNull(capabilities);
 395             requireNonNull(modelContext);
 396         }
 397     }
 398
 399     /**
 400      * Schema builder that tries to build schema context from provided sources or biggest subset of it.
 401      */
 402     private final class SchemaSetup implements FutureCallback<EffectiveModelContext> {
 403         private final SettableFuture<SchemaResult> resultFuture = SettableFuture.create();
 404
 405         private final Set<AvailableCapability> nonModuleBasedCapabilities = new HashSet<>();
 406         private final Map<QName, FailureReason> unresolvedCapabilites = new HashMap<>();
 407         private final Set<AvailableCapability> resolvedCapabilities = new HashSet<>();
 408
 409         private final DeviceSources deviceSources;
 410         private final NetconfSessionPreferences remoteSessionCapabilities;
 411
 412         private Collection<SourceIdentifier> requiredSources;
 413
 414         SchemaSetup(final DeviceSources deviceSources, final NetconfSessionPreferences remoteSessionCapabilities) {
 415             this.deviceSources = deviceSources;
 416             this.remoteSessionCapabilities = remoteSessionCapabilities;
 417
 418             // If device supports notifications and does not contain necessary modules, add them automatically
 419             if (remoteSessionCapabilities.containsNonModuleCapability(
 420                     XmlNetconfConstants.URN_IETF_PARAMS_NETCONF_CAPABILITY_NOTIFICATION_1_0)) {
 421                 deviceSources.getRequiredSourcesQName().addAll(
 422                         Arrays.asList(
 423                                 org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.notification._1._0.rev080714
 424                                         .$YangModuleInfoImpl.getInstance().getName(),
 425                                 org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.yang.types.rev130715
 426                                         .$YangModuleInfoImpl.getInstance().getName()
 427                         )
 428                 );
 429             }
 430
 431             requiredSources = deviceSources.getRequiredSources();
 432             final Collection<SourceIdentifier> missingSources = filterMissingSources(requiredSources);
 433
 434             addUnresolvedCapabilities(getQNameFromSourceIdentifiers(missingSources),
 435                 UnavailableCapability.FailureReason.MissingSource);
 436             requiredSources.removeAll(missingSources);
 437         }
 438
 439         ListenableFuture<SchemaResult> startResolution() {
 440             trySetupSchema();
 441             return resultFuture;
 442         }
 443
 444         @Override
 445         public void onSuccess(final EffectiveModelContext result) {
 446             LOG.debug("{}: Schema context built successfully from {}", id, requiredSources);
 447
 448             final Collection<QName> filteredQNames = Sets.difference(deviceSources.getRequiredSourcesQName(),
 449                     unresolvedCapabilites.keySet());
 450             resolvedCapabilities.addAll(filteredQNames.stream()
 451                 .map(capability -> new AvailableCapabilityBuilder()
 452                     .setCapability(capability.toString())
 453                     .setCapabilityOrigin(remoteSessionCapabilities.capabilityOrigin(capability))
 454                     .build())
 455                 .collect(Collectors.toList()));
 456
 457             nonModuleBasedCapabilities.addAll(remoteSessionCapabilities.nonModuleCaps().keySet().stream()
 458                 .map(capability -> new AvailableCapabilityBuilder()
 459                     .setCapability(capability)
 460                     .setCapabilityOrigin(remoteSessionCapabilities.capabilityOrigin(capability))
 461                     .build())
 462                 .collect(Collectors.toList()));
 463
 464
 465             resultFuture.set(new SchemaResult(new NetconfDeviceCapabilities(ImmutableMap.copyOf(unresolvedCapabilites),
 466                 ImmutableSet.copyOf(resolvedCapabilities), ImmutableSet.copyOf(nonModuleBasedCapabilities)), result));
 467         }
 468
 469         @Override
 470         public void onFailure(final Throwable cause) {
 471             // schemaBuilderFuture.checkedGet() throws only SchemaResolutionException
 472             // that might be wrapping a MissingSchemaSourceException so we need to look
 473             // at the cause of the exception to make sure we don't misinterpret it.
 474             if (cause instanceof MissingSchemaSourceException) {
 475                 requiredSources = handleMissingSchemaSourceException((MissingSchemaSourceException) cause);
 476             } else if (cause instanceof SchemaResolutionException) {
 477                 requiredSources = handleSchemaResolutionException((SchemaResolutionException) cause);
 478             } else {
 479                 LOG.debug("Unhandled failure", cause);
 480                 resultFuture.setException(cause);
 481                 // No more trying...
 482                 return;
 483             }
 484
 485             trySetupSchema();
 486         }
 487
 488         private void trySetupSchema() {
 489             if (!requiredSources.isEmpty()) {
 490                 // Initiate async resolution, drive it back based on the result
 491                 LOG.trace("{}: Trying to build schema context from {}", id, requiredSources);
 492                 Futures.addCallback(schemaContextFactory.createEffectiveModelContext(requiredSources), this,
 493                     MoreExecutors.directExecutor());
 494             } else {
 495                 LOG.debug("{}: no more sources for schema context", id);
 496                 resultFuture.setException(new EmptySchemaContextException(id + ": No more sources for schema context"));
 497             }
 498         }
 499
 500         private List<SourceIdentifier> filterMissingSources(final Collection<SourceIdentifier> origSources) {
 501             return origSources.parallelStream().filter(sourceIdentifier -> {
 502                 try {
 503                     schemaRepository.getSchemaSource(sourceIdentifier, YangTextSchemaSource.class).get();
 504                     return false;
 505                 } catch (InterruptedException | ExecutionException e) {
 506                     return true;
 507                 }
 508             }).collect(Collectors.toList());
 509         }
 510
 511         private void addUnresolvedCapabilities(final Collection<QName> capabilities, final FailureReason reason) {
 512             for (QName s : capabilities) {
 513                 unresolvedCapabilites.put(s, reason);
 514             }
 515         }
 516
 517         private List<SourceIdentifier> handleMissingSchemaSourceException(
 518                 final MissingSchemaSourceException exception) {
 519             // In case source missing, try without it
 520             final SourceIdentifier missingSource = exception.getSourceId();
 521             LOG.warn("{}: Unable to build schema context, missing source {}, will reattempt without it",
 522                 id, missingSource);
 523             LOG.debug("{}: Unable to build schema context, missing source {}, will reattempt without it",
 524                 id, missingSource, exception);
 525             final var qNameOfMissingSource = getQNameFromSourceIdentifiers(Sets.newHashSet(missingSource));
 526             if (!qNameOfMissingSource.isEmpty()) {
 527                 addUnresolvedCapabilities(qNameOfMissingSource, UnavailableCapability.FailureReason.MissingSource);
 528             }
 529             return stripUnavailableSource(missingSource);
 530         }
 531
 532         private Collection<SourceIdentifier> handleSchemaResolutionException(
 533                 final SchemaResolutionException resolutionException) {
 534             // In case resolution error, try only with resolved sources
 535             // There are two options why schema resolution exception occurred : unsatisfied imports or flawed model
 536             // FIXME Do we really have assurance that these two cases cannot happen at once?
 537             if (resolutionException.getFailedSource() != null) {
 538                 // flawed model - exclude it
 539                 final SourceIdentifier failedSourceId = resolutionException.getFailedSource();
 540                 LOG.warn("{}: Unable to build schema context, failed to resolve source {}, will reattempt without it",
 541                     id, failedSourceId);
 542                 LOG.warn("{}: Unable to build schema context, failed to resolve source {}, will reattempt without it",
 543                     id, failedSourceId, resolutionException);
 544                 addUnresolvedCapabilities(getQNameFromSourceIdentifiers(List.of(failedSourceId)),
 545                         UnavailableCapability.FailureReason.UnableToResolve);
 546                 return stripUnavailableSource(resolutionException.getFailedSource());
 547             }
 548             // unsatisfied imports
 549             addUnresolvedCapabilities(
 550                 getQNameFromSourceIdentifiers(resolutionException.getUnsatisfiedImports().keySet()),
 551                 UnavailableCapability.FailureReason.UnableToResolve);
 552             LOG.warn("{}: Unable to build schema context, unsatisfied imports {}, will reattempt with resolved only",
 553                 id, resolutionException.getUnsatisfiedImports());
 554             LOG.debug("{}: Unable to build schema context, unsatisfied imports {}, will reattempt with resolved only",
 555                 id, resolutionException.getUnsatisfiedImports(), resolutionException);
 556             return resolutionException.getResolvedSources();
 557         }
 558
 559         private List<SourceIdentifier> stripUnavailableSource(final SourceIdentifier sourceIdToRemove) {
 560             final var tmp = new ArrayList<>(requiredSources);
 561             checkState(tmp.remove(sourceIdToRemove), "%s: Trying to remove %s from %s failed", id, sourceIdToRemove,
 562                 requiredSources);
 563             return tmp;
 564         }
 565
 566         private Collection<QName> getQNameFromSourceIdentifiers(final Collection<SourceIdentifier> identifiers) {
 567             final Collection<QName> qNames = Collections2.transform(identifiers, this::getQNameFromSourceIdentifier);
 568
 569             if (qNames.isEmpty()) {
 570                 LOG.debug("{}: Unable to map any source identifiers to a capability reported by device : {}", id,
 571                         identifiers);
 572             }
 573             return Collections2.filter(qNames, Predicates.notNull());
 574         }
 575
 576         private QName getQNameFromSourceIdentifier(final SourceIdentifier identifier) {
 577             // Required sources are all required and provided merged in DeviceSourcesResolver
 578             for (final QName qname : deviceSources.getRequiredSourcesQName()) {
 579                 if (!qname.getLocalName().equals(identifier.name().getLocalName())) {
 580                     continue;
 581                 }
 582
 583                 if (Objects.equals(identifier.revision(), qname.getRevision().orElse(null))) {
 584                     return qname;
 585                 }
 586             }
 587             LOG.warn("Unable to map identifier to a devices reported capability: {} Available: {}",identifier,
 588                     deviceSources.getRequiredSourcesQName());
 589             // return null since we cannot find the QName,
 590             // this capability will be removed from required sources and not reported as unresolved-capability
 591             return null;
 592         }
 593     }
 594 }