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 com.google.common.base.Preconditions;
  11 import com.google.common.collect.ImmutableMap;
  12 import java.io.IOException;
  13 import java.net.URISyntaxException;
  14 import java.util.Iterator;
  15 import javax.xml.stream.XMLOutputFactory;
  16 import javax.xml.stream.XMLStreamException;
  17 import javax.xml.stream.XMLStreamWriter;
  18 import javax.xml.transform.dom.DOMResult;
  19 import javax.xml.transform.dom.DOMSource;
  20 import org.eclipse.jdt.annotation.Nullable;
  21 import org.opendaylight.netconf.api.DocumentedException;
  22 import org.opendaylight.netconf.api.xml.XmlElement;
  23 import org.opendaylight.netconf.api.xml.XmlNetconfConstants;
  24 import org.opendaylight.netconf.api.xml.XmlUtil;
  25 import org.opendaylight.yangtools.rfc7952.data.api.NormalizedMetadata;
  26 import org.opendaylight.yangtools.rfc7952.data.util.NormalizedMetadataWriter;
  27 import org.opendaylight.yangtools.yang.common.QName;
  28 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  29 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  30 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  31 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  32 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeWriter;
  33 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  34 import org.opendaylight.yangtools.yang.data.codec.xml.XmlCodecFactory;
  35 import org.opendaylight.yangtools.yang.data.codec.xml.XmlParserStream;
  36 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNormalizedNodeStreamWriter;
  37 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeResult;
  38 import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
  39 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  40 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  41 import org.slf4j.Logger;
  42 import org.slf4j.LoggerFactory;
  43 import org.w3c.dom.Document;
  44 import org.xml.sax.SAXException;
  45
  46 public final class NetconfUtil {
  47     /**
  48      * Shim interface to handle differences around namespace handling between various XMLStreamWriter implementations.
  49      * Specifically:
  50      * <ul>
  51      *   <li>OpenJDK DOM writer (com.sun.xml.internal.stream.writers.XMLDOMWriterImpl) throws
  52      *       UnsupportedOperationException from its setNamespaceContext() method</li>
  53      *   <li>Woodstox DOM writer (com.ctc.wstx.dom.WstxDOMWrappingWriter) works with namespace context, but treats
  54      *       setPrefix() calls as hints -- which are not discoverable.</li>
  55      * </ul>
  56      *
  57      * <p>
  58      * Due to this we perform a quick test for behavior and decide the appropriate strategy.
  59      */
  60     @FunctionalInterface
  61     private interface NamespaceSetter {
  62         void initializeNamespace(XMLStreamWriter writer) throws XMLStreamException;
  63
  64         static NamespaceSetter forFactory(final XMLOutputFactory xmlFactory) {
  65             final String netconfNamespace = NETCONF_QNAME.getNamespace().toString();
  66             final AnyXmlNamespaceContext namespaceContext = new AnyXmlNamespaceContext(ImmutableMap.of(
  67                 "op", netconfNamespace));
  68
  69             try {
  70                 final XMLStreamWriter testWriter = xmlFactory.createXMLStreamWriter(new DOMResult(
  71                     XmlUtil.newDocument()));
  72                 testWriter.setNamespaceContext(namespaceContext);
  73             } catch (final UnsupportedOperationException e) {
  74                 // This happens with JDK's DOM writer, which we may be using
  75                 LOG.warn("Unable to set namespace context, falling back to setPrefix()", e);
  76                 return writer -> writer.setPrefix("op", netconfNamespace);
  77             } catch (XMLStreamException e) {
  78                 throw new ExceptionInInitializerError(e);
  79             }
  80
  81             // Success, we can use setNamespaceContext()
  82             return writer -> writer.setNamespaceContext(namespaceContext);
  83         }
  84     }
  85
  86     private static final Logger LOG = LoggerFactory.getLogger(NetconfUtil.class);
  87
  88     public static final QName NETCONF_QNAME =
  89             QName.create("urn:ietf:params:xml:ns:netconf:base:1.0", "2011-06-01", "netconf").intern();
  90     public static final QName NETCONF_DATA_QNAME = QName.create(NETCONF_QNAME, "data").intern();
  91
  92     public static final XMLOutputFactory XML_FACTORY;
  93
  94     static {
  95         XML_FACTORY = XMLOutputFactory.newFactory();
  96         XML_FACTORY.setProperty(XMLOutputFactory.IS_REPAIRING_NAMESPACES, false);
  97     }
  98
  99     private static final NamespaceSetter XML_NAMESPACE_SETTER = NamespaceSetter.forFactory(XML_FACTORY);
 100
 101     private NetconfUtil() {
 102
 103     }
 104
 105     public static Document checkIsMessageOk(final Document response) throws DocumentedException {
 106         XmlElement element = XmlElement.fromDomDocument(response);
 107         Preconditions.checkState(element.getName().equals(XmlNetconfConstants.RPC_REPLY_KEY));
 108         element = element.getOnlyChildElement();
 109         if (element.getName().equals(XmlNetconfConstants.OK)) {
 110             return response;
 111         }
 112         LOG.warn("Can not load last configuration. Operation failed.");
 113         throw new IllegalStateException("Can not load last configuration. Operation failed: "
 114                 + XmlUtil.toString(response));
 115     }
 116
 117     @SuppressWarnings("checkstyle:IllegalCatch")
 118     public static void writeNormalizedNode(final NormalizedNode<?, ?> normalized, final DOMResult result,
 119                                            final SchemaPath schemaPath, final SchemaContext context)
 120             throws IOException, XMLStreamException {
 121         final XMLStreamWriter writer = XML_FACTORY.createXMLStreamWriter(result);
 122         try (
 123              NormalizedNodeStreamWriter normalizedNodeStreamWriter =
 124                      XMLStreamNormalizedNodeStreamWriter.create(writer, context, schemaPath);
 125              NormalizedNodeWriter normalizedNodeWriter =
 126                      NormalizedNodeWriter.forStreamWriter(normalizedNodeStreamWriter)
 127         ) {
 128             normalizedNodeWriter.write(normalized);
 129             normalizedNodeWriter.flush();
 130         } finally {
 131             try {
 132                 if (writer != null) {
 133                     writer.close();
 134                 }
 135             } catch (final Exception e) {
 136                 LOG.warn("Unable to close resource properly", e);
 137             }
 138         }
 139     }
 140
 141     @SuppressWarnings("checkstyle:IllegalCatch")
 142     public static void writeNormalizedNode(final NormalizedNode<?, ?> normalized,
 143                                            final @Nullable NormalizedMetadata metadata,
 144                                            final DOMResult result, final SchemaPath schemaPath,
 145                                            final SchemaContext context) throws IOException, XMLStreamException {
 146         if (metadata == null) {
 147             writeNormalizedNode(normalized, result, schemaPath, context);
 148             return;
 149         }
 150
 151         final XMLStreamWriter writer = XML_FACTORY.createXMLStreamWriter(result);
 152         XML_NAMESPACE_SETTER.initializeNamespace(writer);
 153         try (
 154              NormalizedNodeStreamWriter normalizedNodeStreamWriter =
 155                      XMLStreamNormalizedNodeStreamWriter.create(writer, context, schemaPath);
 156                 NormalizedMetadataWriter normalizedNodeWriter =
 157                      NormalizedMetadataWriter.forStreamWriter(normalizedNodeStreamWriter)
 158         ) {
 159             normalizedNodeWriter.write(normalized, metadata);
 160             normalizedNodeWriter.flush();
 161         } finally {
 162             try {
 163                 if (writer != null) {
 164                     writer.close();
 165                 }
 166             } catch (final Exception e) {
 167                 LOG.warn("Unable to close resource properly", e);
 168             }
 169         }
 170     }
 171
 172     public static void writeFilter(final YangInstanceIdentifier query, final DOMResult result,
 173             final SchemaPath schemaPath, final SchemaContext context) throws IOException, XMLStreamException {
 174         if (query.isEmpty()) {
 175             // No query at all
 176             return;
 177         }
 178
 179         final XMLStreamWriter xmlWriter = XML_FACTORY.createXMLStreamWriter(result);
 180         try {
 181             try (NormalizedNodeStreamWriter writer =
 182                     XMLStreamNormalizedNodeStreamWriter.create(xmlWriter, context, schemaPath)) {
 183                 final Iterator<PathArgument> it = query.getPathArguments().iterator();
 184                 final PathArgument first = it.next();
 185                 StreamingContext.fromSchemaAndQNameChecked(context, first.getNodeType()).streamToWriter(writer, first,
 186                     it);
 187             }
 188         } finally {
 189             xmlWriter.close();
 190         }
 191     }
 192
 193     public static NormalizedNodeResult transformDOMSourceToNormalizedNode(final SchemaContext schemaContext,
 194             final DOMSource value) throws XMLStreamException, URISyntaxException, IOException, SAXException {
 195         final NormalizedNodeResult resultHolder = new NormalizedNodeResult();
 196         final NormalizedNodeStreamWriter writer = ImmutableNormalizedNodeStreamWriter.from(resultHolder);
 197         final XmlCodecFactory codecs = XmlCodecFactory.create(schemaContext);
 198         final ContainerSchemaNode dataRead = new NodeContainerProxy(NETCONF_DATA_QNAME, schemaContext.getChildNodes());
 199         try (XmlParserStream xmlParserStream = XmlParserStream.create(writer, codecs, dataRead)) {
 200             xmlParserStream.traverse(value);
 201         }
 202         return resultHolder;
 203     }
 204 }