restconf/restconf-nb-bierman02/src/main/java/org/opendaylight/netconf/sal/streams/listeners/ListenerAdapter.java

   1 /*
   2  * Copyright (c) 2014, 2016 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.streams.listeners;
   9
  10 import com.google.common.base.Preconditions;
  11 import java.io.IOException;
  12 import java.util.Collection;
  13 import java.util.Map;
  14 import java.util.Map.Entry;
  15 import javax.annotation.Nonnull;
  16 import javax.xml.stream.XMLStreamException;
  17 import javax.xml.transform.dom.DOMResult;
  18 import org.json.XML;
  19 import org.opendaylight.mdsal.dom.api.ClusteredDOMDataTreeChangeListener;
  20 import org.opendaylight.netconf.sal.restconf.impl.ControllerContext;
  21 import org.opendaylight.yang.gen.v1.urn.sal.restconf.event.subscription.rev140708.NotificationOutputTypeGrouping.NotificationOutputType;
  22 import org.opendaylight.yangtools.yang.common.QName;
  23 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  24 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
  25 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeWithValue;
  26 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  27 import org.opendaylight.yangtools.yang.data.api.schema.LeafNode;
  28 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  29 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  30 import org.opendaylight.yangtools.yang.data.api.schema.UnkeyedListEntryNode;
  31 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  32 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateNode;
  33 import org.opendaylight.yangtools.yang.data.util.DataSchemaContextTree;
  34 import org.opendaylight.yangtools.yang.model.api.Module;
  35 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  36 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  37 import org.slf4j.Logger;
  38 import org.slf4j.LoggerFactory;
  39 import org.w3c.dom.Document;
  40 import org.w3c.dom.Element;
  41 import org.w3c.dom.Node;
  42
  43 /**
  44  * {@link ListenerAdapter} is responsible to track events, which occurred by
  45  * changing data in data source.
  46  */
  47 public class ListenerAdapter extends AbstractCommonSubscriber implements ClusteredDOMDataTreeChangeListener {
  48
  49     private static final Logger LOG = LoggerFactory.getLogger(ListenerAdapter.class);
  50
  51     private final ControllerContext controllerContext;
  52     private final YangInstanceIdentifier path;
  53     private final String streamName;
  54     private final NotificationOutputType outputType;
  55
  56     /**
  57      * Creates new {@link ListenerAdapter} listener specified by path and stream
  58      * name and register for subscribing.
  59      *
  60      * @param path
  61      *            Path to data in data store.
  62      * @param streamName
  63      *            The name of the stream.
  64      * @param outputType
  65      *            Type of output on notification (JSON, XML)
  66      */
  67     ListenerAdapter(final YangInstanceIdentifier path, final String streamName,
  68             final NotificationOutputType outputType, final ControllerContext controllerContext) {
  69         register(this);
  70         this.outputType = Preconditions.checkNotNull(outputType);
  71         this.path = Preconditions.checkNotNull(path);
  72         Preconditions.checkArgument(streamName != null && !streamName.isEmpty());
  73         this.streamName = streamName;
  74         this.controllerContext = controllerContext;
  75     }
  76
  77     @Override
  78     public void onDataTreeChanged(@Nonnull final Collection<DataTreeCandidate> dataTreeCandidates) {
  79         final String xml = prepareXml(dataTreeCandidates);
  80         if (checkQueryParams(xml, this)) {
  81             prepareAndPostData(xml);
  82         }
  83     }
  84
  85     /**
  86      * Gets the name of the stream.
  87      *
  88      * @return The name of the stream.
  89      */
  90     @Override
  91     public String getStreamName() {
  92         return this.streamName;
  93     }
  94
  95     @Override
  96     public String getOutputType() {
  97         return this.outputType.getName();
  98     }
  99
 100     /**
 101      * Get path pointed to data in data store.
 102      *
 103      * @return Path pointed to data in data store.
 104      */
 105     public YangInstanceIdentifier getPath() {
 106         return this.path;
 107     }
 108
 109     /**
 110      * Prepare data of notification and data to client.
 111      *
 112      * @param xml   data
 113      */
 114     private void prepareAndPostData(final String xml) {
 115         final Event event = new Event(EventType.NOTIFY);
 116         if (this.outputType.equals(NotificationOutputType.JSON)) {
 117             event.setData(XML.toJSONObject(xml).toString());
 118         } else {
 119             event.setData(xml);
 120         }
 121         post(event);
 122     }
 123
 124     /**
 125      * Tracks events of data change by customer.
 126      */
 127
 128     /**
 129      * Prepare data in printable form and transform it to String.
 130      *
 131      * @return Data in printable form.
 132      */
 133     private String prepareXml(final Collection<DataTreeCandidate> candidates) {
 134         final SchemaContext schemaContext = controllerContext.getGlobalSchema();
 135         final DataSchemaContextTree dataContextTree = DataSchemaContextTree.from(schemaContext);
 136         final Document doc = createDocument();
 137         final Element notificationElement = basePartDoc(doc);
 138
 139         final Element dataChangedNotificationEventElement = doc.createElementNS(
 140                 "urn:opendaylight:params:xml:ns:yang:controller:md:sal:remote", "data-changed-notification");
 141
 142         addValuesToDataChangedNotificationEventElement(doc, dataChangedNotificationEventElement, candidates,
 143             schemaContext, dataContextTree);
 144         notificationElement.appendChild(dataChangedNotificationEventElement);
 145         return transformDoc(doc);
 146     }
 147
 148     /**
 149      * Adds values to data changed notification event element.
 150      *
 151      * @param doc
 152      *            {@link Document}
 153      * @param dataChangedNotificationEventElement
 154      *            {@link Element}
 155      * @param dataTreeCandidates
 156      *            {@link DataTreeCandidate}
 157      */
 158     private void addValuesToDataChangedNotificationEventElement(final Document doc,
 159             final Element dataChangedNotificationEventElement,
 160             final Collection<DataTreeCandidate> dataTreeCandidates,
 161             final SchemaContext schemaContext, final DataSchemaContextTree dataSchemaContextTree) {
 162
 163         for (DataTreeCandidate dataTreeCandidate : dataTreeCandidates) {
 164             DataTreeCandidateNode candidateNode = dataTreeCandidate.getRootNode();
 165             if (candidateNode == null) {
 166                 continue;
 167             }
 168             YangInstanceIdentifier yiid = dataTreeCandidate.getRootPath();
 169             addNodeToDataChangeNotificationEventElement(doc, dataChangedNotificationEventElement, candidateNode,
 170                     yiid.getParent(), schemaContext, dataSchemaContextTree);
 171         }
 172     }
 173
 174     private void addNodeToDataChangeNotificationEventElement(final Document doc,
 175             final Element dataChangedNotificationEventElement, final DataTreeCandidateNode candidateNode,
 176             final YangInstanceIdentifier parentYiid, final SchemaContext schemaContext,
 177             final DataSchemaContextTree dataSchemaContextTree) {
 178
 179         java.util.Optional<NormalizedNode<?,?>> optionalNormalizedNode = java.util.Optional.empty();
 180         switch (candidateNode.getModificationType()) {
 181             case APPEARED:
 182             case SUBTREE_MODIFIED:
 183             case WRITE:
 184                 optionalNormalizedNode = candidateNode.getDataAfter();
 185                 break;
 186             case DELETE:
 187             case DISAPPEARED:
 188                 optionalNormalizedNode = candidateNode.getDataBefore();
 189                 break;
 190             case UNMODIFIED:
 191             default:
 192                 break;
 193         }
 194
 195         if (!optionalNormalizedNode.isPresent()) {
 196             LOG.error("No node present in notification for {}", candidateNode);
 197             return;
 198         }
 199
 200         NormalizedNode<?,?> normalizedNode = optionalNormalizedNode.get();
 201         YangInstanceIdentifier yiid = YangInstanceIdentifier.builder(parentYiid)
 202                                                             .append(normalizedNode.getIdentifier()).build();
 203
 204         boolean isNodeMixin = controllerContext.isNodeMixin(yiid);
 205         boolean isSkippedNonLeaf = getLeafNodesOnly() && !(normalizedNode instanceof LeafNode);
 206         if (!isNodeMixin && !isSkippedNonLeaf) {
 207             Node node = null;
 208             switch (candidateNode.getModificationType()) {
 209                 case APPEARED:
 210                 case SUBTREE_MODIFIED:
 211                 case WRITE:
 212                     Operation op = candidateNode.getDataBefore().isPresent() ? Operation.UPDATED : Operation.CREATED;
 213                     node = createCreatedChangedDataChangeEventElement(doc, yiid, normalizedNode, op,
 214                             schemaContext, dataSchemaContextTree);
 215                     break;
 216                 case DELETE:
 217                 case DISAPPEARED:
 218                     node = createDataChangeEventElement(doc, yiid, Operation.DELETED);
 219                     break;
 220                 case UNMODIFIED:
 221                 default:
 222                     break;
 223             }
 224             if (node != null) {
 225                 dataChangedNotificationEventElement.appendChild(node);
 226             }
 227         }
 228
 229         for (DataTreeCandidateNode childNode : candidateNode.getChildNodes()) {
 230             addNodeToDataChangeNotificationEventElement(doc, dataChangedNotificationEventElement, childNode,
 231                                                                         yiid, schemaContext, dataSchemaContextTree);
 232         }
 233     }
 234
 235     /**
 236      * Creates changed event element from data.
 237      *
 238      * @param doc
 239      *            {@link Document}
 240      * @param dataPath
 241      *            Path to data in data store.
 242      * @param operation
 243      *            {@link Operation}
 244      * @return {@link Node} node represented by changed event element.
 245      */
 246     private Node createDataChangeEventElement(final Document doc, final YangInstanceIdentifier dataPath,
 247             final Operation operation) {
 248         final Element dataChangeEventElement = doc.createElement("data-change-event");
 249         final Element pathElement = doc.createElement("path");
 250         addPathAsValueToElement(dataPath, pathElement);
 251         dataChangeEventElement.appendChild(pathElement);
 252
 253         final Element operationElement = doc.createElement("operation");
 254         operationElement.setTextContent(operation.value);
 255         dataChangeEventElement.appendChild(operationElement);
 256
 257         return dataChangeEventElement;
 258     }
 259
 260     private Node createCreatedChangedDataChangeEventElement(final Document doc,
 261             final YangInstanceIdentifier eventPath, final NormalizedNode normalized, final Operation operation,
 262             final SchemaContext schemaContext, final DataSchemaContextTree dataSchemaContextTree) {
 263         final Element dataChangeEventElement = doc.createElement("data-change-event");
 264         final Element pathElement = doc.createElement("path");
 265         addPathAsValueToElement(eventPath, pathElement);
 266         dataChangeEventElement.appendChild(pathElement);
 267
 268         final Element operationElement = doc.createElement("operation");
 269         operationElement.setTextContent(operation.value);
 270         dataChangeEventElement.appendChild(operationElement);
 271
 272         try {
 273             SchemaPath nodePath;
 274             if (normalized instanceof MapEntryNode || normalized instanceof UnkeyedListEntryNode) {
 275                 nodePath = dataSchemaContextTree.getChild(eventPath).getDataSchemaNode().getPath();
 276             } else {
 277                 nodePath = dataSchemaContextTree.getChild(eventPath).getDataSchemaNode().getPath().getParent();
 278             }
 279             final DOMResult domResult = writeNormalizedNode(normalized, schemaContext, nodePath);
 280             final Node result = doc.importNode(domResult.getNode().getFirstChild(), true);
 281             final Element dataElement = doc.createElement("data");
 282             dataElement.appendChild(result);
 283             dataChangeEventElement.appendChild(dataElement);
 284         } catch (final IOException e) {
 285             LOG.error("Error in writer ", e);
 286         } catch (final XMLStreamException e) {
 287             LOG.error("Error processing stream", e);
 288         }
 289
 290         return dataChangeEventElement;
 291     }
 292
 293     /**
 294      * Adds path as value to element.
 295      *
 296      * @param dataPath
 297      *            Path to data in data store.
 298      * @param element
 299      *            {@link Element}
 300      */
 301     @SuppressWarnings("rawtypes")
 302     private void addPathAsValueToElement(final YangInstanceIdentifier dataPath, final Element element) {
 303         final YangInstanceIdentifier normalizedPath = controllerContext.toXpathRepresentation(dataPath);
 304         final StringBuilder textContent = new StringBuilder();
 305
 306         for (final PathArgument pathArgument : normalizedPath.getPathArguments()) {
 307             if (pathArgument instanceof YangInstanceIdentifier.AugmentationIdentifier) {
 308                 continue;
 309             }
 310             textContent.append("/");
 311             writeIdentifierWithNamespacePrefix(element, textContent, pathArgument.getNodeType());
 312             if (pathArgument instanceof NodeIdentifierWithPredicates) {
 313                 final Map<QName, Object> predicates = ((NodeIdentifierWithPredicates) pathArgument).getKeyValues();
 314                 for (final Entry<QName, Object> entry : predicates.entrySet()) {
 315                     final QName keyValue = entry.getKey();
 316                     final String predicateValue = String.valueOf(entry.getValue());
 317                     textContent.append("[");
 318                     writeIdentifierWithNamespacePrefix(element, textContent, keyValue);
 319                     textContent.append("='");
 320                     textContent.append(predicateValue);
 321                     textContent.append("'");
 322                     textContent.append("]");
 323                 }
 324             } else if (pathArgument instanceof NodeWithValue) {
 325                 textContent.append("[.='");
 326                 textContent.append(((NodeWithValue) pathArgument).getValue());
 327                 textContent.append("'");
 328                 textContent.append("]");
 329             }
 330         }
 331         element.setTextContent(textContent.toString());
 332     }
 333
 334     /**
 335      * Writes identifier that consists of prefix and QName.
 336      *
 337      * @param element
 338      *            {@link Element}
 339      * @param textContent
 340      *            StringBuilder
 341      * @param qualifiedName
 342      *            QName
 343      */
 344     private void writeIdentifierWithNamespacePrefix(final Element element, final StringBuilder textContent,
 345             final QName qualifiedName) {
 346         final Module module = controllerContext.getGlobalSchema().findModule(qualifiedName.getModule())
 347                 .get();
 348
 349         textContent.append(module.getName());
 350         textContent.append(":");
 351         textContent.append(qualifiedName.getLocalName());
 352     }
 353
 354     /**
 355      * Consists of three types {@link Operation#CREATED},
 356      * {@link Operation#UPDATED} and {@link Operation#DELETED}.
 357      */
 358     private enum Operation {
 359         CREATED("created"), UPDATED("updated"), DELETED("deleted");
 360
 361         private final String value;
 362
 363         Operation(final String value) {
 364             this.value = value;
 365         }
 366     }
 367 }