X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?a=blobdiff_plain;f=opendaylight%2Fmd-sal%2Fsal-netconf-connector%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fcontroller%2Fsal%2Fconnect%2Fnetconf%2FNetconfDevice.java;h=b57a8912ccd1fe67875f6b6d37e571259b1c23f1;hb=8ce853c0627e829d40fe18e550bc807efbcbafee;hp=cc9eb5a851271c8ed221d94038b9db5e35f92059;hpb=971b179000ef1cc56699de35061cf6f97d4cf36f;p=controller.git

diff --git a/opendaylight/md-sal/sal-netconf-connector/src/main/java/org/opendaylight/controller/sal/connect/netconf/NetconfDevice.java b/opendaylight/md-sal/sal-netconf-connector/src/main/java/org/opendaylight/controller/sal/connect/netconf/NetconfDevice.java
index cc9eb5a851..b57a8912cc 100644
--- a/opendaylight/md-sal/sal-netconf-connector/src/main/java/org/opendaylight/controller/sal/connect/netconf/NetconfDevice.java
+++ b/opendaylight/md-sal/sal-netconf-connector/src/main/java/org/opendaylight/controller/sal/connect/netconf/NetconfDevice.java
@@ -7,6 +7,7 @@
  */
 package org.opendaylight.controller.sal.connect.netconf;
 
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Function;
 import com.google.common.base.Optional;
 import com.google.common.base.Preconditions;
@@ -20,21 +21,34 @@ import com.google.common.util.concurrent.ListenableFuture;
 import com.google.common.util.concurrent.ListeningExecutorService;
 import com.google.common.util.concurrent.MoreExecutors;
 import java.util.Collection;
+import java.util.HashSet;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Set;
 import java.util.concurrent.Callable;
 import java.util.concurrent.ExecutorService;
+import org.opendaylight.controller.md.sal.dom.api.DOMRpcException;
+import org.opendaylight.controller.md.sal.dom.api.DOMRpcResult;
+import org.opendaylight.controller.md.sal.dom.api.DOMRpcService;
 import org.opendaylight.controller.netconf.api.NetconfMessage;
 import org.opendaylight.controller.sal.connect.api.MessageTransformer;
 import org.opendaylight.controller.sal.connect.api.RemoteDevice;
 import org.opendaylight.controller.sal.connect.api.RemoteDeviceCommunicator;
 import org.opendaylight.controller.sal.connect.api.RemoteDeviceHandler;
-import org.opendaylight.controller.sal.connect.netconf.listener.NetconfSessionCapabilities;
+import org.opendaylight.controller.sal.connect.netconf.listener.NetconfDeviceCapabilities;
+import org.opendaylight.controller.sal.connect.netconf.listener.NetconfDeviceCommunicator;
+import org.opendaylight.controller.sal.connect.netconf.listener.NetconfSessionPreferences;
 import org.opendaylight.controller.sal.connect.netconf.sal.NetconfDeviceRpc;
 import org.opendaylight.controller.sal.connect.netconf.schema.NetconfRemoteSchemaYangSourceProvider;
+import org.opendaylight.controller.sal.connect.netconf.schema.mapping.NetconfMessageTransformer;
+import org.opendaylight.controller.sal.connect.netconf.util.NetconfMessageTransformUtil;
 import org.opendaylight.controller.sal.connect.util.RemoteDeviceId;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.monitoring.extension.rev131210.$YangModuleInfoImpl;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.netconf.notifications.rev120206.NetconfCapabilityChange;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.netconf.node.topology.rev150114.netconf.node.fields.unavailable.capabilities.UnavailableCapability;
+import org.opendaylight.yangtools.sal.binding.generator.impl.ModuleInfoBackedContext;
 import org.opendaylight.yangtools.yang.common.QName;
+import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
 import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
 import org.opendaylight.yangtools.yang.model.repo.api.SchemaContextFactory;
@@ -51,10 +65,30 @@ import org.slf4j.LoggerFactory;
 /**
  *  This is a mediator between NetconfDeviceCommunicator and NetconfDeviceSalFacade
  */
-public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilities, NetconfMessage> {
+public final class NetconfDevice implements RemoteDevice<NetconfSessionPreferences, NetconfMessage, NetconfDeviceCommunicator> {
 
     private static final Logger logger = LoggerFactory.getLogger(NetconfDevice.class);
 
+    /**
+     * Initial schema context contains schemas for netconf monitoring and netconf notifications
+     */
+    public static final SchemaContext INIT_SCHEMA_CTX;
+
+    static {
+        try {
+            final ModuleInfoBackedContext moduleInfoBackedContext = ModuleInfoBackedContext.create();
+            moduleInfoBackedContext.addModuleInfos(
+                    Lists.newArrayList(
+                            $YangModuleInfoImpl.getInstance(),
+                            org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.notification._1._0.rev080714.$YangModuleInfoImpl.getInstance(),
+                            org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.netconf.base._1._0.rev110601.$YangModuleInfoImpl.getInstance()));
+            INIT_SCHEMA_CTX = moduleInfoBackedContext.tryToCreateSchemaContext().get();
+        } catch (final RuntimeException e) {
+            logger.error("Unable to prepare schema context for netconf initialization", e);
+            throw new ExceptionInInitializerError(e);
+        }
+    }
+
     public static final Function<QName, SourceIdentifier> QNAME_TO_SOURCE_ID_FUNCTION = new Function<QName, SourceIdentifier>() {
         @Override
         public SourceIdentifier apply(final QName input) {
@@ -63,31 +97,48 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
     };
 
     private final RemoteDeviceId id;
+    private final boolean reconnectOnSchemasChange;
 
     private final SchemaContextFactory schemaContextFactory;
-    private final RemoteDeviceHandler<NetconfSessionCapabilities> salFacade;
+    private final RemoteDeviceHandler<NetconfSessionPreferences> salFacade;
     private final ListeningExecutorService processingExecutor;
     private final SchemaSourceRegistry schemaRegistry;
-    private final MessageTransformer<NetconfMessage> messageTransformer;
     private final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver;
     private final NotificationHandler notificationHandler;
     private final List<SchemaSourceRegistration<? extends SchemaSourceRepresentation>> sourceRegistrations = Lists.newArrayList();
 
-    public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final RemoteDeviceId id, final RemoteDeviceHandler<NetconfSessionCapabilities> salFacade,
-                         final ExecutorService globalProcessingExecutor, final MessageTransformer<NetconfMessage> messageTransformer) {
+    // Message transformer is constructed once the schemas are available
+    private MessageTransformer<NetconfMessage> messageTransformer;
+
+    public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final RemoteDeviceId id, final RemoteDeviceHandler<NetconfSessionPreferences> salFacade,
+                         final ExecutorService globalProcessingExecutor) {
+        this(schemaResourcesDTO, id, salFacade, globalProcessingExecutor, false);
+    }
+
+    /**
+     * Create rpc implementation capable of handling RPC for monitoring and notifications even before the schemas of remote device are downloaded
+     */
+    static NetconfDeviceRpc getRpcForInitialization(final NetconfDeviceCommunicator listener) {
+        return new NetconfDeviceRpc(INIT_SCHEMA_CTX, listener, new NetconfMessageTransformer(INIT_SCHEMA_CTX));
+    }
+
+
+    // FIXME reduce parameters
+    public NetconfDevice(final SchemaResourcesDTO schemaResourcesDTO, final RemoteDeviceId id, final RemoteDeviceHandler<NetconfSessionPreferences> salFacade,
+                         final ExecutorService globalProcessingExecutor, final boolean reconnectOnSchemasChange) {
         this.id = id;
+        this.reconnectOnSchemasChange = reconnectOnSchemasChange;
         this.schemaRegistry = schemaResourcesDTO.getSchemaRegistry();
-        this.messageTransformer = messageTransformer;
         this.schemaContextFactory = schemaResourcesDTO.getSchemaContextFactory();
         this.salFacade = salFacade;
         this.stateSchemasResolver = schemaResourcesDTO.getStateSchemasResolver();
         this.processingExecutor = MoreExecutors.listeningDecorator(globalProcessingExecutor);
-        this.notificationHandler = new NotificationHandler(salFacade, messageTransformer, id);
+        this.notificationHandler = new NotificationHandler(salFacade, id);
     }
 
     @Override
-    public void onRemoteSessionUp(final NetconfSessionCapabilities remoteSessionCapabilities,
-                                  final RemoteDeviceCommunicator<NetconfMessage> listener) {
+    public void onRemoteSessionUp(final NetconfSessionPreferences remoteSessionCapabilities,
+                                  final NetconfDeviceCommunicator listener) {
         // SchemaContext setup has to be performed in a dedicated thread since
         // we are in a netty thread in this method
         // Yang models are being downloaded in this method and it would cause a
@@ -95,20 +146,23 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
         // http://netty.io/wiki/thread-model.html
         logger.debug("{}: Session to remote device established with {}", id, remoteSessionCapabilities);
 
-        final NetconfDeviceRpc deviceRpc = setUpDeviceRpc(listener);
-
-        final DeviceSourcesResolver task = new DeviceSourcesResolver(deviceRpc, remoteSessionCapabilities, id, stateSchemasResolver);
+        final NetconfDeviceRpc initRpc = getRpcForInitialization(listener);
+        final DeviceSourcesResolver task = new DeviceSourcesResolver(remoteSessionCapabilities, id, stateSchemasResolver, initRpc);
         final ListenableFuture<DeviceSources> sourceResolverFuture = processingExecutor.submit(task);
 
+        if(shouldListenOnSchemaChange(remoteSessionCapabilities)) {
+           registerToBaseNetconfStream(initRpc, listener);
+        }
+
         final FutureCallback<DeviceSources> resolvedSourceCallback = new FutureCallback<DeviceSources>() {
             @Override
             public void onSuccess(final DeviceSources result) {
-                addProvidedSourcesToSchemaRegistry(deviceRpc, result);
+                addProvidedSourcesToSchemaRegistry(initRpc, result);
                 setUpSchema(result);
             }
 
             private void setUpSchema(final DeviceSources result) {
-                processingExecutor.submit(new RecursiveSchemaSetup(result, remoteSessionCapabilities, deviceRpc, listener));
+                processingExecutor.submit(new RecursiveSchemaSetup(result, remoteSessionCapabilities, listener));
             }
 
             @Override
@@ -121,12 +175,52 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
         Futures.addCallback(sourceResolverFuture, resolvedSourceCallback);
     }
 
-    private void handleSalInitializationSuccess(final SchemaContext result, final NetconfSessionCapabilities remoteSessionCapabilities, final NetconfDeviceRpc deviceRpc) {
-        updateMessageTransformer(result);
+    private void registerToBaseNetconfStream(final NetconfDeviceRpc deviceRpc, final NetconfDeviceCommunicator listener) {
+       final CheckedFuture<DOMRpcResult, DOMRpcException> rpcResultListenableFuture =
+                deviceRpc.invokeRpc(NetconfMessageTransformUtil.toPath(NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_QNAME), NetconfMessageTransformUtil.CREATE_SUBSCRIPTION_RPC_CONTENT);
+
+        final NotificationHandler.NotificationFilter filter = new NotificationHandler.NotificationFilter() {
+            @Override
+            public Optional<NormalizedNode<?, ?>> filterNotification(final NormalizedNode<?, ?> notification) {
+                if (isCapabilityChanged(notification)) {
+                    logger.info("{}: Schemas change detected, reconnecting", id);
+                    // Only disconnect is enough, the reconnecting nature of the connector will take care of reconnecting
+                    listener.disconnect();
+                    return Optional.absent();
+                }
+                return Optional.<NormalizedNode<?, ?>>of(notification);
+            }
+
+            private boolean isCapabilityChanged(final NormalizedNode<?, ?> notification) {
+                return notification.getNodeType().equals(NetconfCapabilityChange.QNAME);
+            }
+        };
+
+        Futures.addCallback(rpcResultListenableFuture, new FutureCallback<DOMRpcResult>() {
+            @Override
+            public void onSuccess(final DOMRpcResult domRpcResult) {
+                notificationHandler.addNotificationFilter(filter);
+            }
+
+            @Override
+            public void onFailure(final Throwable t) {
+                logger.warn("Unable to subscribe to base notification stream. Schemas will not be reloaded on the fly", t);
+            }
+        });
+    }
+
+    private boolean shouldListenOnSchemaChange(final NetconfSessionPreferences remoteSessionCapabilities) {
+        return remoteSessionCapabilities.isNotificationsSupported() && reconnectOnSchemasChange;
+    }
+
+    @VisibleForTesting
+    void handleSalInitializationSuccess(final SchemaContext result, final NetconfSessionPreferences remoteSessionCapabilities, final DOMRpcService deviceRpc) {
+        messageTransformer = new NetconfMessageTransformer(result);
+
+        updateTransformer(messageTransformer);
+        notificationHandler.onRemoteSchemaUp(messageTransformer);
         salFacade.onDeviceConnected(result, remoteSessionCapabilities, deviceRpc);
-        notificationHandler.onRemoteSchemaUp();
 
-        logger.debug("{}: Initialization in sal successful", id);
         logger.info("{}: Netconf connector initialized successfully", id);
     }
 
@@ -134,14 +228,18 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
         logger.error("{}: Initialization in sal failed, disconnecting from device", id, t);
         listener.close();
         onRemoteSessionDown();
+        resetMessageTransformer();
     }
 
     /**
-     * Update initial message transformer to use retrieved schema
-     * @param currentSchemaContext
+     * Set the transformer to null as is in initial state
      */
-    private void updateMessageTransformer(final SchemaContext currentSchemaContext) {
-        messageTransformer.onGlobalContextUpdated(currentSchemaContext);
+    private void resetMessageTransformer() {
+        updateTransformer(null);
+    }
+
+    private void updateTransformer(final MessageTransformer<NetconfMessage> transformer) {
+        messageTransformer = transformer;
     }
 
     private void addProvidedSourcesToSchemaRegistry(final NetconfDeviceRpc deviceRpc, final DeviceSources deviceSources) {
@@ -152,16 +250,20 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
         }
     }
 
-    private NetconfDeviceRpc setUpDeviceRpc(final RemoteDeviceCommunicator<NetconfMessage> listener) {
-       return new NetconfDeviceRpc(listener, messageTransformer);
-    }
-
     @Override
     public void onRemoteSessionDown() {
+        notificationHandler.onRemoteSchemaDown();
+
         salFacade.onDeviceDisconnected();
         for (final SchemaSourceRegistration<? extends SchemaSourceRepresentation> sourceRegistration : sourceRegistrations) {
             sourceRegistration.close();
         }
+        resetMessageTransformer();
+    }
+
+    @Override
+    public void onRemoteSessionFailed(final Throwable throwable) {
+        salFacade.onDeviceFailed(throwable);
     }
 
     @Override
@@ -200,18 +302,24 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
      * Schema building callable.
      */
     private static class DeviceSourcesResolver implements Callable<DeviceSources> {
+
         private final NetconfDeviceRpc deviceRpc;
-        private final NetconfSessionCapabilities remoteSessionCapabilities;
+        private final NetconfSessionPreferences remoteSessionCapabilities;
         private final RemoteDeviceId id;
         private final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver;
 
-        public DeviceSourcesResolver(final NetconfDeviceRpc deviceRpc, final NetconfSessionCapabilities remoteSessionCapabilities, final RemoteDeviceId id, final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver) {
+        DeviceSourcesResolver(final NetconfDeviceRpc deviceRpc, final NetconfSessionPreferences remoteSessionCapabilities,
+                                     final RemoteDeviceId id, final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver) {
             this.deviceRpc = deviceRpc;
             this.remoteSessionCapabilities = remoteSessionCapabilities;
             this.id = id;
             this.stateSchemasResolver = stateSchemasResolver;
         }
 
+        public DeviceSourcesResolver(final NetconfSessionPreferences remoteSessionCapabilities, final RemoteDeviceId id, final NetconfStateSchemas.NetconfStateSchemasResolver stateSchemasResolver, final NetconfDeviceRpc rpcForMonitoring) {
+            this(rpcForMonitoring, remoteSessionCapabilities, id, stateSchemasResolver);
+        }
+
         @Override
         public DeviceSources call() throws Exception {
 
@@ -234,15 +342,16 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
             }
 
 
-            // TODO should we perform this ? We have a mechanism to fix initialization of devices not reporting or required modules in hello
-            // That is overriding capabilities in configuration using attribute yang-module-capabilities
-            // This is more user friendly even though it clashes with attribute yang-module-capabilities
-            // Some devices do not report all required models in hello message, but provide them
+            // Here all the sources reported in netconf monitoring are merged with those reported in hello.
+            // It is necessary to perform this since submodules are not mentioned in hello but still required.
+            // This clashes with the option of a user to specify supported yang models manually in configuration for netconf-connector
+            // and as a result one is not able to fully override yang models of a device. It is only possible to add additional models.
             final Set<SourceIdentifier> providedSourcesNotRequired = Sets.difference(providedSources, requiredSources);
             if (!providedSourcesNotRequired.isEmpty()) {
                 logger.warn("{}: Netconf device provides additional yang models not reported in hello message capabilities: {}",
                         id, providedSourcesNotRequired);
                 logger.warn("{}: Adding provided but not required sources as required to prevent failures", id);
+                logger.debug("{}: Netconf device reported in hello: {}", id, requiredSources);
                 requiredSources.addAll(providedSourcesNotRequired);
             }
 
@@ -252,7 +361,6 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
 
     /**
      * Contains RequiredSources - sources from capabilities.
-     *
      */
     private static final class DeviceSources {
         private final Collection<SourceIdentifier> requiredSources;
@@ -278,15 +386,15 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
      */
     private final class RecursiveSchemaSetup implements Runnable {
         private final DeviceSources deviceSources;
-        private final NetconfSessionCapabilities remoteSessionCapabilities;
-        private final NetconfDeviceRpc deviceRpc;
+        private final NetconfSessionPreferences remoteSessionCapabilities;
         private final RemoteDeviceCommunicator<NetconfMessage> listener;
+        private final NetconfDeviceCapabilities capabilities;
 
-        public RecursiveSchemaSetup(final DeviceSources deviceSources, final NetconfSessionCapabilities remoteSessionCapabilities, final NetconfDeviceRpc deviceRpc, final RemoteDeviceCommunicator<NetconfMessage> listener) {
+        public RecursiveSchemaSetup(final DeviceSources deviceSources, final NetconfSessionPreferences remoteSessionCapabilities, final RemoteDeviceCommunicator<NetconfMessage> listener) {
             this.deviceSources = deviceSources;
             this.remoteSessionCapabilities = remoteSessionCapabilities;
-            this.deviceRpc = deviceRpc;
             this.listener = listener;
+            this.capabilities = remoteSessionCapabilities.getNetconfDeviceCapabilities();
         }
 
         @Override
@@ -297,6 +405,7 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
         /**
          * Recursively build schema context, in case of success or final failure notify device
          */
+        // FIXME reimplement without recursion
         private void setUpSchema(final Collection<SourceIdentifier> requiredSources) {
             logger.trace("{}: Trying to build schema context from {}", id, requiredSources);
 
@@ -313,7 +422,10 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
                 @Override
                 public void onSuccess(final SchemaContext result) {
                     logger.debug("{}: Schema context built successfully from {}", id, requiredSources);
-                    handleSalInitializationSuccess(result, remoteSessionCapabilities, deviceRpc);
+                    final Collection<QName> filteredQNames = Sets.difference(remoteSessionCapabilities.getModuleBasedCaps(), capabilities.getUnresolvedCapabilites().keySet());
+                    capabilities.addCapabilities(filteredQNames);
+                    capabilities.addNonModuleBasedCapabilities(remoteSessionCapabilities.getNonModuleCaps());
+                    handleSalInitializationSuccess(result, remoteSessionCapabilities, getDeviceSpecificRpc(result));
                 }
 
                 @Override
@@ -322,12 +434,15 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
                     if (t instanceof MissingSchemaSourceException) {
                         final SourceIdentifier missingSource = ((MissingSchemaSourceException) t).getSourceId();
                         logger.warn("{}: Unable to build schema context, missing source {}, will reattempt without it", id, missingSource);
+                        capabilities.addUnresolvedCapabilities(getQNameFromSourceIdentifiers(Sets.newHashSet(missingSource)), UnavailableCapability.FailureReason.MissingSource);
                         setUpSchema(stripMissingSource(requiredSources, missingSource));
 
                     // In case resolution error, try only with resolved sources
                     } else if (t instanceof SchemaResolutionException) {
                         // TODO check for infinite loop
                         final SchemaResolutionException resolutionException = (SchemaResolutionException) t;
+                        final Set<SourceIdentifier> unresolvedSources = resolutionException.getUnsatisfiedImports().keySet();
+                        capabilities.addUnresolvedCapabilities(getQNameFromSourceIdentifiers(unresolvedSources), UnavailableCapability.FailureReason.UnableToResolve);
                         logger.warn("{}: Unable to build schema context, unsatisfied imports {}, will reattempt with resolved only", id, resolutionException.getUnsatisfiedImports());
                         setUpSchema(resolutionException.getResolvedSources());
                     // unknown error, fail
@@ -340,11 +455,39 @@ public final class NetconfDevice implements RemoteDevice<NetconfSessionCapabilit
             Futures.addCallback(schemaBuilderFuture, RecursiveSchemaBuilderCallback);
         }
 
+        private NetconfDeviceRpc getDeviceSpecificRpc(final SchemaContext result) {
+            return new NetconfDeviceRpc(result, listener, new NetconfMessageTransformer(result));
+        }
+
         private Collection<SourceIdentifier> stripMissingSource(final Collection<SourceIdentifier> requiredSources, final SourceIdentifier sIdToRemove) {
             final LinkedList<SourceIdentifier> sourceIdentifiers = Lists.newLinkedList(requiredSources);
             final boolean removed = sourceIdentifiers.remove(sIdToRemove);
             Preconditions.checkState(removed, "{}: Trying to remove {} from {} failed", id, sIdToRemove, requiredSources);
             return sourceIdentifiers;
         }
+
+        private Collection<QName> getQNameFromSourceIdentifiers(final Collection<SourceIdentifier> identifiers) {
+            final Collection<QName> qNames = new HashSet<>();
+            for (final SourceIdentifier source : identifiers) {
+                final Optional<QName> qname = getQNameFromSourceIdentifier(source);
+                if (qname.isPresent()) {
+                    qNames.add(qname.get());
+                }
+            }
+            if (qNames.isEmpty()) {
+                logger.debug("Unable to map any source identfiers to a capability reported by device : " + identifiers);
+            }
+            return qNames;
+        }
+
+        private Optional<QName> getQNameFromSourceIdentifier(final SourceIdentifier identifier) {
+            for (final QName qname : remoteSessionCapabilities.getModuleBasedCaps()) {
+                if (qname.getLocalName().equals(identifier.getName())
+                        && qname.getFormattedRevision().equals(identifier.getRevision())) {
+                    return Optional.of(qname);
+                }
+            }
+            throw new IllegalArgumentException("Unable to map identifier to a devices reported capability: " + identifier);
+        }
     }
 }