restconf/restconf-nb/src/main/java/org/opendaylight/restconf/nb/rfc8040/jersey/providers/XmlNormalizedNodeBodyWriter.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 package org.opendaylight.restconf.nb.rfc8040.jersey.providers;
   9
  10 import java.io.IOException;
  11 import java.io.OutputStream;
  12 import java.nio.charset.StandardCharsets;
  13 import javanet.staxutils.IndentingXMLStreamWriter;
  14 import javax.ws.rs.Produces;
  15 import javax.ws.rs.core.MediaType;
  16 import javax.ws.rs.ext.Provider;
  17 import javax.xml.XMLConstants;
  18 import javax.xml.stream.FactoryConfigurationError;
  19 import javax.xml.stream.XMLOutputFactory;
  20 import javax.xml.stream.XMLStreamException;
  21 import javax.xml.stream.XMLStreamWriter;
  22 import org.eclipse.jdt.annotation.Nullable;
  23 import org.opendaylight.restconf.api.MediaTypes;
  24 import org.opendaylight.restconf.api.query.PrettyPrintParam;
  25 import org.opendaylight.restconf.nb.rfc8040.jersey.providers.api.RestconfNormalizedNodeWriter;
  26 import org.opendaylight.restconf.nb.rfc8040.legacy.QueryParameters;
  27 import org.opendaylight.yangtools.yang.common.QName;
  28 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  29 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  30 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  31 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  32 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
  33 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack;
  34 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack.Inference;
  35
  36 @Provider
  37 @Produces({ MediaTypes.APPLICATION_YANG_DATA_XML, MediaType.APPLICATION_XML, MediaType.TEXT_XML })
  38 public final class XmlNormalizedNodeBodyWriter extends AbstractNormalizedNodeBodyWriter {
  39     private static final XMLOutputFactory XML_FACTORY;
  40
  41     static {
  42         XML_FACTORY = XMLOutputFactory.newFactory();
  43         XML_FACTORY.setProperty(XMLOutputFactory.IS_REPAIRING_NAMESPACES, true);
  44     }
  45
  46     @Override
  47     void writeOperationOutput(final SchemaInferenceStack stack, final QueryParameters writerParameters,
  48             final ContainerNode output, final OutputStream entityStream) throws IOException {
  49         // RpcDefinition/ActionDefinition is not supported as initial codec in XMLStreamWriter, so we need to emit
  50         // initial output declaration.
  51         final var xmlWriter = createXmlWriter(entityStream, writerParameters.prettyPrint());
  52         final var nnWriter = createNormalizedNodeWriter(xmlWriter, stack.toInference(), writerParameters);
  53         writeElements(xmlWriter, nnWriter, output);
  54         nnWriter.flush();
  55     }
  56
  57     @Override
  58     void writeData(final SchemaInferenceStack stack, final QueryParameters writerParameters, final NormalizedNode data,
  59             final OutputStream entityStream) throws IOException {
  60         final boolean isRoot;
  61         if (!stack.isEmpty()) {
  62             stack.exit();
  63             isRoot = false;
  64         } else {
  65             isRoot = true;
  66         }
  67
  68         final var xmlWriter = createXmlWriter(entityStream, writerParameters.prettyPrint());
  69         final var nnWriter = createNormalizedNodeWriter(xmlWriter, stack.toInference(), writerParameters);
  70         if (data instanceof MapEntryNode mapEntry) {
  71             // Restconf allows returning one list item. We need to wrap it
  72             // in map node in order to serialize it properly
  73             nnWriter.write(ImmutableNodes.mapNodeBuilder(data.name().getNodeType()).addChild(mapEntry).build());
  74         } else if (isRoot) {
  75             if (data instanceof ContainerNode container && container.isEmpty()) {
  76                 writeEmptyDataNode(xmlWriter, container);
  77             } else {
  78                 writeAndWrapInDataNode(xmlWriter, nnWriter, data);
  79             }
  80         } else {
  81             nnWriter.write(data);
  82         }
  83         nnWriter.flush();
  84     }
  85
  86     private static XMLStreamWriter createXmlWriter(final OutputStream entityStream,
  87             final @Nullable PrettyPrintParam prettyPrint) {
  88         final XMLStreamWriter xmlWriter;
  89         try {
  90             xmlWriter = XML_FACTORY.createXMLStreamWriter(entityStream, StandardCharsets.UTF_8.name());
  91         } catch (XMLStreamException | FactoryConfigurationError e) {
  92             throw new IllegalStateException(e);
  93         }
  94
  95         return prettyPrint != null && prettyPrint.value() ? new IndentingXMLStreamWriter(xmlWriter) : xmlWriter;
  96     }
  97
  98     private static RestconfNormalizedNodeWriter createNormalizedNodeWriter(final XMLStreamWriter xmlWriter,
  99             final Inference inference, final QueryParameters writerParameters) {
 100         return ParameterAwareNormalizedNodeWriter.forStreamWriter(
 101             XMLStreamNormalizedNodeStreamWriter.create(xmlWriter, inference),
 102             writerParameters.depth(), writerParameters.fields());
 103     }
 104
 105     private static void writeAndWrapInDataNode(final XMLStreamWriter xmlWriter,
 106             final RestconfNormalizedNodeWriter nnWriter, final NormalizedNode data) throws IOException {
 107         final QName nodeType = data.name().getNodeType();
 108         final String namespace = nodeType.getNamespace().toString();
 109         try {
 110             xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX, nodeType.getLocalName(), namespace);
 111             xmlWriter.writeDefaultNamespace(namespace);
 112             nnWriter.write(data);
 113             xmlWriter.writeEndElement();
 114             xmlWriter.flush();
 115         } catch (XMLStreamException e) {
 116             throw new IOException("Failed to write elements", e);
 117         }
 118     }
 119
 120     private static void writeEmptyDataNode(final XMLStreamWriter xmlWriter, final ContainerNode data)
 121             throws IOException {
 122         final QName nodeType = data.name().getNodeType();
 123         final String namespace = nodeType.getNamespace().toString();
 124         try {
 125             xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX, nodeType.getLocalName(), namespace);
 126             xmlWriter.writeDefaultNamespace(namespace);
 127             xmlWriter.writeEndElement();
 128             xmlWriter.flush();
 129         } catch (XMLStreamException e) {
 130             throw new IOException("Failed to write elements", e);
 131         }
 132     }
 133
 134     private static void writeElements(final XMLStreamWriter xmlWriter, final RestconfNormalizedNodeWriter nnWriter,
 135             final ContainerNode data) throws IOException {
 136         final QName nodeType = data.name().getNodeType();
 137         final String namespace = nodeType.getNamespace().toString();
 138         try {
 139             xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX, nodeType.getLocalName(), namespace);
 140             xmlWriter.writeDefaultNamespace(namespace);
 141             for (var child : data.body()) {
 142                 nnWriter.write(child);
 143             }
 144             nnWriter.flush();
 145             xmlWriter.writeEndElement();
 146             xmlWriter.flush();
 147         } catch (final XMLStreamException e) {
 148             throw new IOException("Failed to write elements", e);
 149         }
 150     }
 151 }