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