netconf/netconf-util/src/main/java/org/opendaylight/netconf/util/NetconfUtil.java

   1 /*
   2  * Copyright (c) 2013 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.util;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11
  12 import com.google.common.collect.ImmutableMap;
  13 import java.io.IOException;
  14 import java.net.URISyntaxException;
  15 import java.util.Iterator;
  16 import java.util.List;
  17 import java.util.Map.Entry;
  18 import java.util.stream.Collectors;
  19 import javax.xml.stream.XMLOutputFactory;
  20 import javax.xml.stream.XMLStreamException;
  21 import javax.xml.stream.XMLStreamWriter;
  22 import javax.xml.transform.dom.DOMResult;
  23 import javax.xml.transform.dom.DOMSource;
  24 import org.eclipse.jdt.annotation.Nullable;
  25 import org.opendaylight.netconf.api.DocumentedException;
  26 import org.opendaylight.netconf.api.xml.XmlElement;
  27 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  28 import org.opendaylight.netconf.api.xml.XmlUtil;
  29 import org.opendaylight.yangtools.rcf8528.data.util.EmptyMountPointContext;
  30 import org.opendaylight.yangtools.rfc7952.data.api.NormalizedMetadata;
  31 import org.opendaylight.yangtools.rfc7952.data.util.NormalizedMetadataWriter;
  32 import org.opendaylight.yangtools.rfc8528.data.api.MountPointContext;
  33 import org.opendaylight.yangtools.yang.common.QName;
  34 import org.opendaylight.yangtools.yang.common.QNameModule;
  35 import org.opendaylight.yangtools.yang.common.Revision;
  36 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  37 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
  38 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  39 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  40 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  41 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeWriter;
  42 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  43 import org.opendaylight.yangtools.yang.data.codec.xml.XmlCodecFactory;
  44 import org.opendaylight.yangtools.yang.data.codec.xml.XmlParserStream;
  45 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNormalizedNodeStreamWriter;
  46 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeResult;
  47 import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
  48 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  49 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  50 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  51 import org.slf4j.Logger;
  52 import org.slf4j.LoggerFactory;
  53 import org.w3c.dom.Document;
  54 import org.w3c.dom.Element;
  55 import org.xml.sax.SAXException;
  56
  57 public final class NetconfUtil {
  58     /**
  59      * Shim interface to handle differences around namespace handling between various XMLStreamWriter implementations.
  60      * Specifically:
  61      * <ul>
  62      *   <li>OpenJDK DOM writer (com.sun.xml.internal.stream.writers.XMLDOMWriterImpl) throws
  63      *       UnsupportedOperationException from its setNamespaceContext() method</li>
  64      *   <li>Woodstox DOM writer (com.ctc.wstx.dom.WstxDOMWrappingWriter) works with namespace context, but treats
  65      *       setPrefix() calls as hints -- which are not discoverable.</li>
  66      * </ul>
  67      *
  68      * <p>
  69      * Due to this we perform a quick test for behavior and decide the appropriate strategy.
  70      */
  71     @FunctionalInterface
  72     private interface NamespaceSetter {
  73         void initializeNamespace(XMLStreamWriter writer) throws XMLStreamException;
  74
  75         static NamespaceSetter forFactory(final XMLOutputFactory xmlFactory) {
  76             final String netconfNamespace = NETCONF_QNAME.getNamespace().toString();
  77             final AnyXmlNamespaceContext namespaceContext = new AnyXmlNamespaceContext(ImmutableMap.of(
  78                 "op", netconfNamespace));
  79
  80             try {
  81                 final XMLStreamWriter testWriter = xmlFactory.createXMLStreamWriter(new DOMResult(
  82                     XmlUtil.newDocument()));
  83                 testWriter.setNamespaceContext(namespaceContext);
  84             } catch (final UnsupportedOperationException e) {
  85                 // This happens with JDK's DOM writer, which we may be using
  86                 LOG.warn("Unable to set namespace context, falling back to setPrefix()", e);
  87                 return writer -> writer.setPrefix("op", netconfNamespace);
  88             } catch (XMLStreamException e) {
  89                 throw new ExceptionInInitializerError(e);
  90             }
  91
  92             // Success, we can use setNamespaceContext()
  93             return writer -> writer.setNamespaceContext(namespaceContext);
  94         }
  95     }
  96
  97     private static final Logger LOG = LoggerFactory.getLogger(NetconfUtil.class);
  98
  99     // FIXME: document what exactly this QName means, as it is not referring to a tangible node nor the ietf-module.
 100     // FIXME: what is this contract saying?
 101     //        - is it saying all data is going to be interpreted with this root?
 102     //        - is this saying we are following a specific interface contract (i.e. do we have schema mounts?)
 103     //        - is it also inferring some abilities w.r.t. RFC8342?
 104     public static final QName NETCONF_QNAME = QName.create(QNameModule.create(SchemaContext.NAME.getNamespace(),
 105         Revision.of("2011-06-01")), "netconf").intern();
 106     // FIXME: is this the device-bound revision?
 107     public static final QName NETCONF_DATA_QNAME = QName.create(NETCONF_QNAME, "data").intern();
 108
 109     public static final XMLOutputFactory XML_FACTORY;
 110
 111     static {
 112         final XMLOutputFactory f = XMLOutputFactory.newFactory();
 113         // FIXME: not repairing namespaces is probably common, this should be availabe as common XML constant.
 114         f.setProperty(XMLOutputFactory.IS_REPAIRING_NAMESPACES, false);
 115         XML_FACTORY = f;
 116     }
 117
 118     private static final NamespaceSetter XML_NAMESPACE_SETTER = NamespaceSetter.forFactory(XML_FACTORY);
 119
 120     private NetconfUtil() {
 121         // No-op
 122     }
 123
 124     public static Document checkIsMessageOk(final Document response) throws DocumentedException {
 125         final XmlElement docElement = XmlElement.fromDomDocument(response);
 126         // FIXME: we should throw DocumentedException here
 127         checkState(XmlNetconfConstants.RPC_REPLY_KEY.equals(docElement.getName()));
 128         final XmlElement element = docElement.getOnlyChildElement();
 129         if (XmlNetconfConstants.OK.equals(element.getName())) {
 130             return response;
 131         }
 132
 133         LOG.warn("Can not load last configuration. Operation failed.");
 134         // FIXME: we should be throwing a DocumentedException here
 135         throw new IllegalStateException("Can not load last configuration. Operation failed: "
 136                 + XmlUtil.toString(response));
 137     }
 138
 139     @SuppressWarnings("checkstyle:IllegalCatch")
 140     public static void writeNormalizedNode(final NormalizedNode<?, ?> normalized, final DOMResult result,
 141                                            final SchemaPath schemaPath, final EffectiveModelContext context)
 142             throws IOException, XMLStreamException {
 143         final XMLStreamWriter writer = XML_FACTORY.createXMLStreamWriter(result);
 144         try (
 145              NormalizedNodeStreamWriter normalizedNodeStreamWriter =
 146                      XMLStreamNormalizedNodeStreamWriter.create(writer, context, schemaPath);
 147              NormalizedNodeWriter normalizedNodeWriter =
 148                      NormalizedNodeWriter.forStreamWriter(normalizedNodeStreamWriter)
 149         ) {
 150             normalizedNodeWriter.write(normalized);
 151             normalizedNodeWriter.flush();
 152         } finally {
 153             try {
 154                 if (writer != null) {
 155                     writer.close();
 156                 }
 157             } catch (final Exception e) {
 158                 LOG.warn("Unable to close resource properly", e);
 159             }
 160         }
 161     }
 162
 163     @SuppressWarnings("checkstyle:IllegalCatch")
 164     public static void writeNormalizedNode(final NormalizedNode<?, ?> normalized,
 165                                            final @Nullable NormalizedMetadata metadata,
 166                                            final DOMResult result, final SchemaPath schemaPath,
 167                                            final EffectiveModelContext context) throws IOException, XMLStreamException {
 168         if (metadata == null) {
 169             writeNormalizedNode(normalized, result, schemaPath, context);
 170             return;
 171         }
 172
 173         final XMLStreamWriter writer = XML_FACTORY.createXMLStreamWriter(result);
 174         XML_NAMESPACE_SETTER.initializeNamespace(writer);
 175         try (
 176              NormalizedNodeStreamWriter normalizedNodeStreamWriter =
 177                      XMLStreamNormalizedNodeStreamWriter.create(writer, context, schemaPath);
 178                 NormalizedMetadataWriter normalizedNodeWriter =
 179                      NormalizedMetadataWriter.forStreamWriter(normalizedNodeStreamWriter)
 180         ) {
 181             normalizedNodeWriter.write(normalized, metadata);
 182             normalizedNodeWriter.flush();
 183         } finally {
 184             try {
 185                 if (writer != null) {
 186                     writer.close();
 187                 }
 188             } catch (final Exception e) {
 189                 LOG.warn("Unable to close resource properly", e);
 190             }
 191         }
 192     }
 193
 194     /**
 195      * Writing subtree filter specified by {@link YangInstanceIdentifier} into {@link DOMResult}.
 196      *
 197      * @param query      path to the root node
 198      * @param result     DOM result holder
 199      * @param schemaPath schema path of the parent node
 200      * @param context    mountpoint schema context
 201      * @throws IOException        failed to write filter into {@link NormalizedNodeStreamWriter}
 202      * @throws XMLStreamException failed to serialize filter into XML document
 203      */
 204     public static void writeFilter(final YangInstanceIdentifier query, final DOMResult result,
 205             final SchemaPath schemaPath, final EffectiveModelContext context) throws IOException, XMLStreamException {
 206         if (query.isEmpty()) {
 207             // No query at all
 208             return;
 209         }
 210
 211         final XMLStreamWriter xmlWriter = XML_FACTORY.createXMLStreamWriter(result);
 212         try {
 213             try (NormalizedNodeStreamWriter streamWriter =
 214                     XMLStreamNormalizedNodeStreamWriter.create(xmlWriter, context, schemaPath);
 215                  EmptyListXmlWriter writer = new EmptyListXmlWriter(streamWriter, xmlWriter)) {
 216                 final Iterator<PathArgument> it = query.getPathArguments().iterator();
 217                 final PathArgument first = it.next();
 218                 StreamingContext.fromSchemaAndQNameChecked(context, first.getNodeType()).streamToWriter(writer, first,
 219                     it);
 220             }
 221         } finally {
 222             xmlWriter.close();
 223         }
 224     }
 225
 226     /**
 227      * Writing subtree filter specified by parent {@link YangInstanceIdentifier} and specific fields
 228      * into {@link DOMResult}. Field paths are relative to parent query path.
 229      *
 230      * @param query      path to the root node
 231      * @param result     DOM result holder
 232      * @param schemaPath schema path of the parent node
 233      * @param context    mountpoint schema context
 234      * @param fields     list of specific fields for which the filter should be created
 235      * @throws IOException        failed to write filter into {@link NormalizedNodeStreamWriter}
 236      * @throws XMLStreamException failed to serialize filter into XML document
 237      * @throws NullPointerException if any argument is null
 238      */
 239     public static void writeFilter(final YangInstanceIdentifier query, final DOMResult result,
 240                                    final SchemaPath schemaPath, final EffectiveModelContext context,
 241                                    final List<YangInstanceIdentifier> fields) throws IOException, XMLStreamException {
 242         if (query.isEmpty() || fields.isEmpty()) {
 243             // No query at all
 244             return;
 245         }
 246         final List<YangInstanceIdentifier> aggregatedFields = aggregateFields(fields);
 247         final PathNode rootNode = constructPathArgumentTree(query, aggregatedFields);
 248
 249         final XMLStreamWriter xmlWriter = XML_FACTORY.createXMLStreamWriter(result);
 250         try {
 251             try (NormalizedNodeStreamWriter streamWriter =
 252                     XMLStreamNormalizedNodeStreamWriter.create(xmlWriter, context, schemaPath);
 253                  EmptyListXmlWriter writer = new EmptyListXmlWriter(streamWriter, xmlWriter)) {
 254                 final PathArgument first = rootNode.element();
 255                 StreamingContext.fromSchemaAndQNameChecked(context, first.getNodeType())
 256                         .streamToWriter(writer, first, rootNode);
 257             }
 258         } finally {
 259             xmlWriter.close();
 260         }
 261     }
 262
 263     /**
 264      * Writing subtree filter specified by parent {@link YangInstanceIdentifier} and specific fields
 265      * into {@link Element}. Field paths are relative to parent query path. Filter is created without following
 266      * {@link EffectiveModelContext}.
 267      *
 268      * @param query         path to the root node
 269      * @param fields        list of specific fields for which the filter should be created
 270      * @param filterElement XML filter element to which the created filter will be written
 271      */
 272     public static void writeSchemalessFilter(final YangInstanceIdentifier query,
 273                                              final List<YangInstanceIdentifier> fields, final Element filterElement) {
 274         pathArgumentTreeToXmlStructure(constructPathArgumentTree(query, aggregateFields(fields)), filterElement);
 275     }
 276
 277     private static void pathArgumentTreeToXmlStructure(final PathNode pathArgumentTree, final Element data) {
 278         final PathArgument pathArg = pathArgumentTree.element();
 279
 280         final QName nodeType = pathArg.getNodeType();
 281         final String elementNamespace = nodeType.getNamespace().toString();
 282
 283         if (data.getElementsByTagNameNS(elementNamespace, nodeType.getLocalName()).getLength() != 0) {
 284             // element has already been written as list key
 285             return;
 286         }
 287
 288         final Element childElement = data.getOwnerDocument().createElementNS(elementNamespace, nodeType.getLocalName());
 289         data.appendChild(childElement);
 290         if (pathArg instanceof NodeIdentifierWithPredicates) {
 291             appendListKeyNodes(childElement, (NodeIdentifierWithPredicates) pathArg);
 292         }
 293         for (final PathNode childrenNode : pathArgumentTree.children()) {
 294             pathArgumentTreeToXmlStructure(childrenNode, childElement);
 295         }
 296     }
 297
 298     /**
 299      * Appending list key elements to parent element.
 300      *
 301      * @param parentElement parent XML element to which children elements are appended
 302      * @param listEntryId   list entry identifier
 303      */
 304     public static void appendListKeyNodes(final Element parentElement, final NodeIdentifierWithPredicates listEntryId) {
 305         for (Entry<QName, Object> key : listEntryId.entrySet()) {
 306             final Element keyElement = parentElement.getOwnerDocument().createElementNS(
 307                     key.getKey().getNamespace().toString(), key.getKey().getLocalName());
 308             keyElement.setTextContent(key.getValue().toString());
 309             parentElement.appendChild(keyElement);
 310         }
 311     }
 312
 313     /**
 314      * Aggregation of the fields paths based on parenthesis. Only parent/enclosing {@link YangInstanceIdentifier}
 315      * are kept. For example, paths '/x/y/z', '/x/y', and '/x' are aggregated into single field path: '/x'
 316      *
 317      * @param fields paths of fields
 318      * @return filtered {@link List} of paths
 319      */
 320     private static List<YangInstanceIdentifier> aggregateFields(final List<YangInstanceIdentifier> fields) {
 321         return fields.stream()
 322                 .filter(field -> fields.stream()
 323                         .filter(fieldYiid -> !field.equals(fieldYiid))
 324                         .noneMatch(fieldYiid -> fieldYiid.contains(field)))
 325                 .collect(Collectors.toList());
 326     }
 327
 328     /**
 329      * Construct a tree based on the parent {@link YangInstanceIdentifier} and provided list of fields. The goal of this
 330      * procedure is the elimination of the redundancy that is introduced by potentially overlapping parts of the fields
 331      * paths.
 332      *
 333      * @param query  path to parent element
 334      * @param fields subpaths relative to parent path that identify specific fields
 335      * @return created {@link TreeNode} structure
 336      */
 337     private static PathNode constructPathArgumentTree(final YangInstanceIdentifier query,
 338             final List<YangInstanceIdentifier> fields) {
 339         final Iterator<PathArgument> queryIterator = query.getPathArguments().iterator();
 340         final PathNode rootTreeNode = new PathNode(queryIterator.next());
 341
 342         PathNode queryTreeNode = rootTreeNode;
 343         while (queryIterator.hasNext()) {
 344             queryTreeNode = queryTreeNode.ensureChild(queryIterator.next());
 345         }
 346
 347         for (final YangInstanceIdentifier field : fields) {
 348             PathNode actualFieldTreeNode = queryTreeNode;
 349             for (final PathArgument fieldPathArg : field.getPathArguments()) {
 350                 actualFieldTreeNode = actualFieldTreeNode.ensureChild(fieldPathArg);
 351             }
 352         }
 353         return rootTreeNode;
 354     }
 355
 356     public static NormalizedNodeResult transformDOMSourceToNormalizedNode(final MountPointContext mountContext,
 357             final DOMSource value) throws XMLStreamException, URISyntaxException, IOException, SAXException {
 358         final NormalizedNodeResult resultHolder = new NormalizedNodeResult();
 359         final NormalizedNodeStreamWriter writer = ImmutableNormalizedNodeStreamWriter.from(resultHolder);
 360         final XmlCodecFactory codecs = XmlCodecFactory.create(mountContext);
 361
 362         // FIXME: we probably need to propagate MountPointContext here and not just the child nodes
 363         final ContainerSchemaNode dataRead = new NodeContainerProxy(NETCONF_DATA_QNAME,
 364             mountContext.getEffectiveModelContext().getChildNodes());
 365         try (XmlParserStream xmlParserStream = XmlParserStream.create(writer, codecs, dataRead)) {
 366             xmlParserStream.traverse(value);
 367         }
 368         return resultHolder;
 369     }
 370
 371
 372     // FIXME: document this interface contract. Does it support RFC8528/RFC8542? How?
 373     public static NormalizedNodeResult transformDOMSourceToNormalizedNode(final EffectiveModelContext schemaContext,
 374             final DOMSource value) throws XMLStreamException, URISyntaxException, IOException, SAXException {
 375         return transformDOMSourceToNormalizedNode(new EmptyMountPointContext(schemaContext), value);
 376     }
 377 }