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.YangInstanceIdentifier.NodeIdentifier;
  29 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  30 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  31 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  32 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  33 import org.opendaylight.yangtools.yang.data.spi.node.ImmutableNodes;
  34 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack;
  35 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack.Inference;
  36
  37 @Provider
  38 @Produces({ MediaTypes.APPLICATION_YANG_DATA_XML, MediaType.APPLICATION_XML, MediaType.TEXT_XML })
  39 public final class XmlNormalizedNodeBodyWriter extends AbstractNormalizedNodeBodyWriter {
  40     private static final XMLOutputFactory XML_FACTORY;
  41
  42     static {
  43         XML_FACTORY = XMLOutputFactory.newFactory();
  44         XML_FACTORY.setProperty(XMLOutputFactory.IS_REPAIRING_NAMESPACES, true);
  45     }
  46
  47     @Override
  48     void writeOperationOutput(final SchemaInferenceStack stack, final QueryParameters writerParameters,
  49             final ContainerNode output, final OutputStream entityStream) throws IOException {
  50         // RpcDefinition/ActionDefinition is not supported as initial codec in XMLStreamWriter, so we need to emit
  51         // initial output declaration.
  52         final var xmlWriter = createXmlWriter(entityStream, writerParameters.prettyPrint());
  53         final var nnWriter = createNormalizedNodeWriter(xmlWriter, stack.toInference(), writerParameters);
  54         writeElements(xmlWriter, nnWriter, output);
  55         nnWriter.flush();
  56     }
  57
  58     @Override
  59     void writeData(final SchemaInferenceStack stack, final QueryParameters writerParameters, final NormalizedNode data,
  60             final OutputStream entityStream) throws IOException {
  61         final boolean isRoot;
  62         if (!stack.isEmpty()) {
  63             stack.exit();
  64             isRoot = false;
  65         } else {
  66             isRoot = true;
  67         }
  68
  69         final var xmlWriter = createXmlWriter(entityStream, writerParameters.prettyPrint());
  70         final var nnWriter = createNormalizedNodeWriter(xmlWriter, stack.toInference(), writerParameters);
  71         if (data instanceof MapEntryNode mapEntry) {
  72             // Restconf allows returning one list item. We need to wrap it
  73             // in map node in order to serialize it properly
  74             nnWriter.write(ImmutableNodes.newSystemMapBuilder()
  75                 .withNodeIdentifier(new NodeIdentifier(data.name().getNodeType()))
  76                 .addChild(mapEntry)
  77                 .build());
  78         } else if (isRoot) {
  79             if (data instanceof ContainerNode container && container.isEmpty()) {
  80                 writeEmptyDataNode(xmlWriter, container);
  81             } else {
  82                 writeAndWrapInDataNode(xmlWriter, nnWriter, data);
  83             }
  84         } else {
  85             nnWriter.write(data);
  86         }
  87         nnWriter.flush();
  88     }
  89
  90     private static XMLStreamWriter createXmlWriter(final OutputStream entityStream,
  91             final @Nullable PrettyPrintParam prettyPrint) {
  92         final XMLStreamWriter xmlWriter;
  93         try {
  94             xmlWriter = XML_FACTORY.createXMLStreamWriter(entityStream, StandardCharsets.UTF_8.name());
  95         } catch (XMLStreamException | FactoryConfigurationError e) {
  96             throw new IllegalStateException(e);
  97         }
  98
  99         return prettyPrint != null && prettyPrint.value() ? new IndentingXMLStreamWriter(xmlWriter) : xmlWriter;
 100     }
 101
 102     private static RestconfNormalizedNodeWriter createNormalizedNodeWriter(final XMLStreamWriter xmlWriter,
 103             final Inference inference, final QueryParameters writerParameters) {
 104         return ParameterAwareNormalizedNodeWriter.forStreamWriter(
 105             XMLStreamNormalizedNodeStreamWriter.create(xmlWriter, inference),
 106             writerParameters.depth(), writerParameters.fields());
 107     }
 108
 109     private static void writeAndWrapInDataNode(final XMLStreamWriter xmlWriter,
 110             final RestconfNormalizedNodeWriter nnWriter, final NormalizedNode data) throws IOException {
 111         final QName nodeType = data.name().getNodeType();
 112         final String namespace = nodeType.getNamespace().toString();
 113         try {
 114             xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX, nodeType.getLocalName(), namespace);
 115             xmlWriter.writeDefaultNamespace(namespace);
 116             nnWriter.write(data);
 117             xmlWriter.writeEndElement();
 118             xmlWriter.flush();
 119         } catch (XMLStreamException e) {
 120             throw new IOException("Failed to write elements", e);
 121         }
 122     }
 123
 124     private static void writeEmptyDataNode(final XMLStreamWriter xmlWriter, final ContainerNode data)
 125             throws IOException {
 126         final QName nodeType = data.name().getNodeType();
 127         final String namespace = nodeType.getNamespace().toString();
 128         try {
 129             xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX, nodeType.getLocalName(), namespace);
 130             xmlWriter.writeDefaultNamespace(namespace);
 131             xmlWriter.writeEndElement();
 132             xmlWriter.flush();
 133         } catch (XMLStreamException e) {
 134             throw new IOException("Failed to write elements", e);
 135         }
 136     }
 137
 138     private static void writeElements(final XMLStreamWriter xmlWriter, final RestconfNormalizedNodeWriter nnWriter,
 139             final ContainerNode data) throws IOException {
 140         final QName nodeType = data.name().getNodeType();
 141         final String namespace = nodeType.getNamespace().toString();
 142         try {
 143             xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX, nodeType.getLocalName(), namespace);
 144             xmlWriter.writeDefaultNamespace(namespace);
 145             for (var child : data.body()) {
 146                 nnWriter.write(child);
 147             }
 148             nnWriter.flush();
 149             xmlWriter.writeEndElement();
 150             xmlWriter.flush();
 151         } catch (final XMLStreamException e) {
 152             throw new IOException("Failed to write elements", e);
 153         }
 154     }
 155 }