yang/yang-data-codec-xml/src/main/java/org/opendaylight/yangtools/yang/data/codec/xml/XmlParserStream.java

   1 /*
   2  * Copyright (c) 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
   9 package org.opendaylight.yangtools.yang.data.codec.xml;
  10
  11 import com.google.common.base.Preconditions;
  12 import java.io.Closeable;
  13 import java.io.Flushable;
  14 import java.io.IOException;
  15 import java.io.StringReader;
  16 import java.net.URI;
  17 import java.net.URISyntaxException;
  18 import java.util.Deque;
  19 import java.util.HashSet;
  20 import java.util.Set;
  21 import javax.xml.parsers.DocumentBuilder;
  22 import javax.xml.parsers.DocumentBuilderFactory;
  23 import javax.xml.parsers.ParserConfigurationException;
  24 import javax.xml.stream.XMLStreamConstants;
  25 import javax.xml.stream.XMLStreamException;
  26 import javax.xml.stream.XMLStreamReader;
  27 import javax.xml.transform.dom.DOMSource;
  28 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  29 import org.opendaylight.yangtools.yang.data.util.AbstractNodeDataWithSchema;
  30 import org.opendaylight.yangtools.yang.data.util.AnyXmlNodeDataWithSchema;
  31 import org.opendaylight.yangtools.yang.data.util.CompositeNodeDataWithSchema;
  32 import org.opendaylight.yangtools.yang.data.util.LeafListEntryNodeDataWithSchema;
  33 import org.opendaylight.yangtools.yang.data.util.LeafListNodeDataWithSchema;
  34 import org.opendaylight.yangtools.yang.data.util.LeafNodeDataWithSchema;
  35 import org.opendaylight.yangtools.yang.data.util.ListEntryNodeDataWithSchema;
  36 import org.opendaylight.yangtools.yang.data.util.ListNodeDataWithSchema;
  37 import org.opendaylight.yangtools.yang.data.util.ParserStreamUtils;
  38 import org.opendaylight.yangtools.yang.data.util.RpcAsContainer;
  39 import org.opendaylight.yangtools.yang.data.util.SimpleNodeDataWithSchema;
  40 import org.opendaylight.yangtools.yang.model.api.AnyXmlSchemaNode;
  41 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
  42 import org.opendaylight.yangtools.yang.model.api.RpcDefinition;
  43 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  44 import org.opendaylight.yangtools.yang.model.api.SchemaNode;
  45 import org.opendaylight.yangtools.yang.model.api.YangModeledAnyXmlSchemaNode;
  46 import org.w3c.dom.Document;
  47 import org.xml.sax.InputSource;
  48 import org.xml.sax.SAXException;
  49
  50 /**
  51  * This class provides functionality for parsing an XML source containing YANG-modeled data. It disallows multiple
  52  * instances of the same element except for leaf-list and list entries. It also expects that the YANG-modeled data in
  53  * the XML source are wrapped in a root element.
  54  */
  55 public final class XmlParserStream implements Closeable, Flushable {
  56
  57     private String rootElement = null;
  58     private final NormalizedNodeStreamWriter writer;
  59     private final XmlCodecFactory codecs;
  60     private final SchemaContext schema;
  61     private final DataSchemaNode parentNode;
  62
  63     private XmlParserStream(final NormalizedNodeStreamWriter writer, final SchemaContext schemaContext,
  64                              final DataSchemaNode parentNode) {
  65         this.schema = Preconditions.checkNotNull(schemaContext);
  66         this.writer = Preconditions.checkNotNull(writer);
  67         this.codecs = XmlCodecFactory.create(schemaContext);
  68         this.parentNode = parentNode;
  69     }
  70
  71     public static XmlParserStream create(final NormalizedNodeStreamWriter writer, final SchemaContext schemaContext,
  72             final SchemaNode parentNode ) {
  73         if (parentNode instanceof RpcDefinition) {
  74             return new XmlParserStream(writer, schemaContext, new RpcAsContainer((RpcDefinition) parentNode));
  75         }
  76         Preconditions.checkArgument(parentNode instanceof DataSchemaNode, "Instance of DataSchemaNode class awaited.");
  77         return new XmlParserStream(writer, schemaContext, (DataSchemaNode) parentNode);
  78     }
  79
  80     public static XmlParserStream create(final NormalizedNodeStreamWriter writer, final SchemaContext schemaContext) {
  81         return new XmlParserStream(writer, schemaContext, schemaContext);
  82     }
  83
  84     /**
  85      * This method parses the XML source and emits node events into a NormalizedNodeStreamWriter based on the
  86      * YANG-modeled data contained in the XML source.
  87      *
  88      * @param reader
  89      *              StAX reader which is to used to walk through the XML source
  90      * @return
  91      *              instance of XmlParserStream
  92      * @throws XMLStreamException
  93      *              if a well-formedness error or an unexpected processing condition occurs while parsing the XML
  94      * @throws URISyntaxException
  95      *              if the namespace URI of an XML element contains a syntax error
  96      * @throws IOException
  97      *              if an error occurs while parsing the value of an anyxml node
  98      * @throws ParserConfigurationException
  99      *              if an error occurs while parsing the value of an anyxml node
 100      * @throws SAXException
 101      *              if an error occurs while parsing the value of an anyxml node
 102      */
 103     public XmlParserStream parse(final XMLStreamReader reader) throws XMLStreamException, URISyntaxException,
 104             IOException, ParserConfigurationException, SAXException {
 105         if (reader.hasNext()) {
 106             final CompositeNodeDataWithSchema compositeNodeDataWithSchema = new CompositeNodeDataWithSchema(parentNode);
 107             reader.nextTag();
 108             rootElement = reader.getLocalName();
 109             read(reader, compositeNodeDataWithSchema);
 110             compositeNodeDataWithSchema.write(writer);
 111         }
 112
 113         return this;
 114     }
 115
 116     private static String readAnyXmlValue(final XMLStreamReader in) throws XMLStreamException {
 117         String result = "";
 118         String anyXmlElementName = in.getLocalName();
 119
 120         while (in.hasNext()) {
 121             int eventType = in.next();
 122
 123             if (eventType == XMLStreamConstants.START_ELEMENT) {
 124                 result += "<" + in.getLocalName() + ">";
 125             } else if (eventType == XMLStreamConstants.END_ELEMENT) {
 126                 if (in.getLocalName().equals(anyXmlElementName)) {
 127                     break;
 128                 }
 129
 130                 result += "</" + in.getLocalName() + ">";
 131             } else if (eventType == XMLStreamConstants.CHARACTERS) {
 132                 result += in.getText();
 133             }
 134         }
 135
 136         return result;
 137     }
 138
 139     private void read(final XMLStreamReader in, final AbstractNodeDataWithSchema parent) throws XMLStreamException,
 140             URISyntaxException, ParserConfigurationException, SAXException, IOException {
 141         if (in.hasNext()) {
 142             if (parent instanceof LeafNodeDataWithSchema || parent instanceof LeafListEntryNodeDataWithSchema) {
 143                 setValue(parent, in.getElementText().trim());
 144                 in.nextTag();
 145                 return;
 146             } else if (parent instanceof LeafListNodeDataWithSchema || parent instanceof ListNodeDataWithSchema) {
 147                 String parentSchemaName = parent.getSchema().getQName().getLocalName();
 148                 String xmlElementName = in.getLocalName();
 149                 while (xmlElementName.equals(parentSchemaName)) {
 150                     AbstractNodeDataWithSchema newChild = newEntryNode(parent);
 151                     read(in, newChild);
 152                     xmlElementName = in.getLocalName();
 153                 }
 154
 155                 return;
 156             } else if (parent instanceof AnyXmlNodeDataWithSchema) {
 157                 setValue(parent, readAnyXmlValue(in));
 158                 in.nextTag();
 159                 return;
 160             }
 161
 162             switch (in.nextTag()) {
 163                 case XMLStreamConstants.START_ELEMENT:
 164                     final Set<String> namesakes = new HashSet<>();
 165                     while (in.hasNext()) {
 166                         String xmlElementName = in.getLocalName();
 167                         String xmlElementNamespace = in.getNamespaceURI();
 168
 169                         if (xmlElementName.equals(rootElement)) {
 170                             break;
 171                         }
 172
 173                         DataSchemaNode parentSchema = parent.getSchema();
 174                         if (parentSchema instanceof YangModeledAnyXmlSchemaNode) {
 175                             parentSchema = ((YangModeledAnyXmlSchemaNode) parentSchema).getSchemaOfAnyXmlData();
 176                         }
 177
 178                         String parentSchemaName = parentSchema.getQName().getLocalName();
 179                         if (parentSchemaName.equals(xmlElementName)
 180                                 && in.getEventType() == XMLStreamConstants.END_ELEMENT) {
 181                             in.nextTag();
 182                             break;
 183                         }
 184
 185                         if (namesakes.contains(xmlElementName)) {
 186                             int lineNumber = in.getLocation().getLineNumber();
 187                             int columnNumber = in.getLocation().getColumnNumber();
 188                             throw new IllegalStateException("Duplicate element \"" + xmlElementName + "\" in XML " +
 189                                     "input at: line " + lineNumber + " column " + columnNumber);
 190                         }
 191                         namesakes.add(xmlElementName);
 192
 193                         Deque<DataSchemaNode> childDataSchemaNodes = ParserStreamUtils.findSchemaNodeByNameAndNamespace(
 194                                 parentSchema, xmlElementName, new URI(xmlElementNamespace));
 195
 196                         if (childDataSchemaNodes.isEmpty()) {
 197                             throw new IllegalStateException("Schema for node with name " + xmlElementName +
 198                                     " and namespace " + xmlElementNamespace + " doesn't exist.");
 199                         }
 200
 201                         AbstractNodeDataWithSchema newChild =
 202                                 ((CompositeNodeDataWithSchema) parent).addChild(childDataSchemaNodes);
 203
 204                         read(in, newChild);
 205                     }
 206                     break;
 207                 case XMLStreamConstants.END_ELEMENT:
 208                     in.nextTag();
 209                     break;
 210             }
 211         }
 212     }
 213
 214     private void setValue(final AbstractNodeDataWithSchema parent, final String value) throws
 215             ParserConfigurationException, SAXException, IOException {
 216         Preconditions.checkArgument(parent instanceof SimpleNodeDataWithSchema, "Node %s is not a simple type",
 217                 parent.getSchema().getQName());
 218         final SimpleNodeDataWithSchema parentSimpleNode = (SimpleNodeDataWithSchema) parent;
 219         Preconditions.checkArgument(parentSimpleNode.getValue() == null, "Node '%s' has already set its value to '%s'",
 220                 parentSimpleNode.getSchema().getQName(), parentSimpleNode.getValue());
 221
 222         final Object translatedValue = translateValueByType(value, parentSimpleNode.getSchema());
 223         parentSimpleNode.setValue(translatedValue);
 224     }
 225
 226     private Object translateValueByType(final String value, final DataSchemaNode node) throws IOException,
 227             SAXException, ParserConfigurationException {
 228         if (node instanceof AnyXmlSchemaNode) {
 229             /*
 230              *  FIXME: Figure out some YANG extension dispatch, which will
 231              *  reuse JSON parsing or XML parsing - anyxml is not well-defined in
 232              * JSON.
 233              */
 234             DocumentBuilder db = DocumentBuilderFactory.newInstance().newDocumentBuilder();
 235             Document doc = db.parse( new InputSource(new StringReader(value)));
 236             doc.normalize();
 237             DOMSource anyXmlValueSource = new DOMSource(doc);
 238
 239             return anyXmlValueSource;
 240         }
 241         return codecs.codecFor(node).deserialize(value);
 242     }
 243
 244     private static AbstractNodeDataWithSchema newEntryNode(final AbstractNodeDataWithSchema parent) {
 245         AbstractNodeDataWithSchema newChild;
 246         if (parent instanceof ListNodeDataWithSchema) {
 247             newChild = new ListEntryNodeDataWithSchema(parent.getSchema());
 248         } else {
 249             newChild = new LeafListEntryNodeDataWithSchema(parent.getSchema());
 250         }
 251         ((CompositeNodeDataWithSchema) parent).addChild(newChild);
 252         return newChild;
 253     }
 254
 255     @Override
 256     public void close() throws IOException {
 257         writer.flush();
 258         writer.close();
 259     }
 260
 261     @Override
 262     public void flush() throws IOException {
 263         writer.flush();
 264     }
 265 }