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.DataSchemaNodeAwareAdaptor;
  29 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  30 import org.opendaylight.yangtools.yang.data.api.schema.stream.SchemaAwareNormalizedNodeStreamWriter;
  31 import org.opendaylight.yangtools.yang.data.util.AbstractNodeDataWithSchema;
  32 import org.opendaylight.yangtools.yang.data.util.AnyXmlNodeDataWithSchema;
  33 import org.opendaylight.yangtools.yang.data.util.CompositeNodeDataWithSchema;
  34 import org.opendaylight.yangtools.yang.data.util.LeafListEntryNodeDataWithSchema;
  35 import org.opendaylight.yangtools.yang.data.util.LeafListNodeDataWithSchema;
  36 import org.opendaylight.yangtools.yang.data.util.LeafNodeDataWithSchema;
  37 import org.opendaylight.yangtools.yang.data.util.ListEntryNodeDataWithSchema;
  38 import org.opendaylight.yangtools.yang.data.util.ListNodeDataWithSchema;
  39 import org.opendaylight.yangtools.yang.data.util.ParserStreamUtils;
  40 import org.opendaylight.yangtools.yang.data.util.RpcAsContainer;
  41 import org.opendaylight.yangtools.yang.data.util.SimpleNodeDataWithSchema;
  42 import org.opendaylight.yangtools.yang.model.api.AnyXmlSchemaNode;
  43 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
  44 import org.opendaylight.yangtools.yang.model.api.RpcDefinition;
  45 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  46 import org.opendaylight.yangtools.yang.model.api.SchemaNode;
  47 import org.opendaylight.yangtools.yang.model.api.YangModeledAnyXmlSchemaNode;
  48 import org.w3c.dom.Document;
  49 import org.xml.sax.InputSource;
  50 import org.xml.sax.SAXException;
  51
  52 /**
  53  * This class provides functionality for parsing an XML source containing YANG-modeled data. It disallows multiple
  54  * instances of the same element except for leaf-list and list entries. It also expects that the YANG-modeled data in
  55  * the XML source are wrapped in a root element.
  56  */
  57 public final class XmlParserStream implements Closeable, Flushable {
  58
  59     private String rootElement = null;
  60     private final SchemaAwareNormalizedNodeStreamWriter writer;
  61     private final XmlCodecFactory codecs;
  62     private final SchemaContext schema;
  63     private final DataSchemaNode parentNode;
  64
  65     private XmlParserStream(final NormalizedNodeStreamWriter writer, final SchemaContext schemaContext,
  66                              final DataSchemaNode parentNode) {
  67         this.schema = Preconditions.checkNotNull(schemaContext);
  68         this.writer = DataSchemaNodeAwareAdaptor.forWriter(writer);
  69         this.codecs = XmlCodecFactory.create(schemaContext);
  70         this.parentNode = parentNode;
  71     }
  72
  73     public static XmlParserStream create(final NormalizedNodeStreamWriter writer, final SchemaContext schemaContext,
  74             final SchemaNode parentNode ) {
  75         if (parentNode instanceof RpcDefinition) {
  76             return new XmlParserStream(writer, schemaContext, new RpcAsContainer((RpcDefinition) parentNode));
  77         }
  78         Preconditions.checkArgument(parentNode instanceof DataSchemaNode, "Instance of DataSchemaNode class awaited.");
  79         return new XmlParserStream(writer, schemaContext, (DataSchemaNode) parentNode);
  80     }
  81
  82     public static XmlParserStream create(final NormalizedNodeStreamWriter writer, final SchemaContext schemaContext) {
  83         return new XmlParserStream(writer, schemaContext, schemaContext);
  84     }
  85
  86     /**
  87      * This method parses the XML source and emits node events into a NormalizedNodeStreamWriter based on the
  88      * YANG-modeled data contained in the XML source.
  89      *
  90      * @param reader
  91      *              StAX reader which is to used to walk through the XML source
  92      * @return
  93      *              instance of XmlParserStream
  94      * @throws XMLStreamException
  95      *              if a well-formedness error or an unexpected processing condition occurs while parsing the XML
  96      * @throws URISyntaxException
  97      *              if the namespace URI of an XML element contains a syntax error
  98      * @throws IOException
  99      *              if an error occurs while parsing the value of an anyxml node
 100      * @throws ParserConfigurationException
 101      *              if an error occurs while parsing the value of an anyxml node
 102      * @throws SAXException
 103      *              if an error occurs while parsing the value of an anyxml node
 104      */
 105     public XmlParserStream parse(final XMLStreamReader reader) throws XMLStreamException, URISyntaxException,
 106             IOException, ParserConfigurationException, SAXException {
 107         if (reader.hasNext()) {
 108             final CompositeNodeDataWithSchema compositeNodeDataWithSchema = new CompositeNodeDataWithSchema(parentNode);
 109             reader.nextTag();
 110             rootElement = reader.getLocalName();
 111             read(reader, compositeNodeDataWithSchema);
 112             compositeNodeDataWithSchema.write(writer);
 113         }
 114
 115         return this;
 116     }
 117
 118     private String readAnyXmlValue(XMLStreamReader in) throws XMLStreamException {
 119         String result = "";
 120         String anyXmlElementName = in.getLocalName();
 121
 122         while (in.hasNext()) {
 123             int eventType = in.next();
 124
 125             if (eventType == XMLStreamConstants.START_ELEMENT) {
 126                 result += "<" + in.getLocalName() + ">";
 127             } else if (eventType == XMLStreamConstants.END_ELEMENT) {
 128                 if (in.getLocalName().equals(anyXmlElementName)) {
 129                     break;
 130                 }
 131
 132                 result += "</" + in.getLocalName() + ">";
 133             } else if (eventType == XMLStreamConstants.CHARACTERS) {
 134                 result += in.getText();
 135             }
 136         }
 137
 138         return result;
 139     }
 140
 141     private void read(final XMLStreamReader in, AbstractNodeDataWithSchema parent) throws XMLStreamException,
 142             URISyntaxException, ParserConfigurationException, SAXException, IOException {
 143         if (in.hasNext()) {
 144             if (parent instanceof LeafNodeDataWithSchema || parent instanceof LeafListEntryNodeDataWithSchema) {
 145                 setValue(parent, in.getElementText().trim());
 146                 in.nextTag();
 147                 return;
 148             } else if (parent instanceof LeafListNodeDataWithSchema || parent instanceof ListNodeDataWithSchema) {
 149                 String parentSchemaName = parent.getSchema().getQName().getLocalName();
 150                 String xmlElementName = in.getLocalName();
 151                 while (xmlElementName.equals(parentSchemaName)) {
 152                     AbstractNodeDataWithSchema newChild = newEntryNode(parent);
 153                     read(in, newChild);
 154                     xmlElementName = in.getLocalName();
 155                 }
 156
 157                 return;
 158             } else if (parent instanceof AnyXmlNodeDataWithSchema) {
 159                 setValue(parent, readAnyXmlValue(in));
 160                 in.nextTag();
 161                 return;
 162             }
 163
 164             switch (in.nextTag()) {
 165                 case XMLStreamConstants.START_ELEMENT:
 166                     final Set<String> namesakes = new HashSet<>();
 167                     while (in.hasNext()) {
 168                         String xmlElementName = in.getLocalName();
 169                         String xmlElementNamespace = in.getNamespaceURI();
 170
 171                         if (xmlElementName.equals(rootElement)) {
 172                             break;
 173                         }
 174
 175                         DataSchemaNode parentSchema = parent.getSchema();
 176                         if (parentSchema instanceof YangModeledAnyXmlSchemaNode) {
 177                             parentSchema = ((YangModeledAnyXmlSchemaNode) parentSchema).getSchemaOfAnyXmlData();
 178                         }
 179
 180                         String parentSchemaName = parentSchema.getQName().getLocalName();
 181                         if (parentSchemaName.equals(xmlElementName)
 182                                 && in.getEventType() == XMLStreamConstants.END_ELEMENT) {
 183                             in.nextTag();
 184                             break;
 185                         }
 186
 187                         if (namesakes.contains(xmlElementName)) {
 188                             int lineNumber = in.getLocation().getLineNumber();
 189                             int columnNumber = in.getLocation().getColumnNumber();
 190                             throw new IllegalStateException("Duplicate element \"" + xmlElementName + "\" in XML " +
 191                                     "input at: line " + lineNumber + " column " + columnNumber);
 192                         }
 193                         namesakes.add(xmlElementName);
 194
 195                         Deque<DataSchemaNode> childDataSchemaNodes = ParserStreamUtils.findSchemaNodeByNameAndNamespace(
 196                                 parentSchema, xmlElementName, new URI(xmlElementNamespace));
 197
 198                         if (childDataSchemaNodes.isEmpty()) {
 199                             throw new IllegalStateException("Schema for node with name " + xmlElementName +
 200                                     " and namespace " + xmlElementNamespace + " doesn't exist.");
 201                         }
 202
 203                         AbstractNodeDataWithSchema newChild =
 204                                 ((CompositeNodeDataWithSchema) parent).addChild(childDataSchemaNodes);
 205
 206                         read(in, newChild);
 207                     }
 208                     break;
 209                 case XMLStreamConstants.END_ELEMENT:
 210                     in.nextTag();
 211                     break;
 212             }
 213         }
 214     }
 215
 216     private void setValue(final AbstractNodeDataWithSchema parent, final String value) throws
 217             ParserConfigurationException, SAXException, IOException {
 218         Preconditions.checkArgument(parent instanceof SimpleNodeDataWithSchema, "Node %s is not a simple type",
 219                 parent.getSchema().getQName());
 220         final SimpleNodeDataWithSchema parentSimpleNode = (SimpleNodeDataWithSchema) parent;
 221         Preconditions.checkArgument(parentSimpleNode.getValue() == null, "Node '%s' has already set its value to '%s'",
 222                 parentSimpleNode.getSchema().getQName(), parentSimpleNode.getValue());
 223
 224         final Object translatedValue = translateValueByType(value, parentSimpleNode.getSchema());
 225         parentSimpleNode.setValue(translatedValue);
 226     }
 227
 228     private Object translateValueByType(final String value, final DataSchemaNode node) throws IOException,
 229             SAXException, ParserConfigurationException {
 230         if (node instanceof AnyXmlSchemaNode) {
 231             /*
 232              *  FIXME: Figure out some YANG extension dispatch, which will
 233              *  reuse JSON parsing or XML parsing - anyxml is not well-defined in
 234              * JSON.
 235              */
 236             DocumentBuilder db = DocumentBuilderFactory.newInstance().newDocumentBuilder();
 237             Document doc = db.parse( new InputSource(new StringReader(value)));
 238             doc.normalize();
 239             DOMSource anyXmlValueSource = new DOMSource(doc);
 240
 241             return anyXmlValueSource;
 242         }
 243         return codecs.codecFor(node).deserialize(value);
 244     }
 245
 246     private AbstractNodeDataWithSchema newEntryNode(final AbstractNodeDataWithSchema parent) {
 247         AbstractNodeDataWithSchema newChild;
 248         if (parent instanceof ListNodeDataWithSchema) {
 249             newChild = new ListEntryNodeDataWithSchema(parent.getSchema());
 250         } else {
 251             newChild = new LeafListEntryNodeDataWithSchema(parent.getSchema());
 252         }
 253         ((CompositeNodeDataWithSchema) parent).addChild(newChild);
 254         return newChild;
 255     }
 256
 257     @Override
 258     public void close() throws IOException {
 259         writer.flush();
 260         writer.close();
 261     }
 262
 263     @Override
 264     public void flush() throws IOException {
 265         writer.flush();
 266     }
 267 }