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 javax.ws.rs.Produces;
  13 import javax.ws.rs.core.MediaType;
  14 import javax.ws.rs.ext.Provider;
  15 import javax.xml.XMLConstants;
  16 import javax.xml.stream.XMLStreamException;
  17 import javax.xml.stream.XMLStreamWriter;
  18 import org.opendaylight.restconf.api.FormatParameters;
  19 import org.opendaylight.restconf.api.MediaTypes;
  20 import org.opendaylight.restconf.nb.rfc8040.jersey.providers.api.RestconfNormalizedNodeWriter;
  21 import org.opendaylight.restconf.nb.rfc8040.legacy.WriterParameters;
  22 import org.opendaylight.restconf.server.spi.FormattableBodySupport;
  23 import org.opendaylight.yangtools.yang.common.QName;
  24 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  25 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  26 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  27 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  28 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  29 import org.opendaylight.yangtools.yang.data.spi.node.ImmutableNodes;
  30 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack;
  31 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack.Inference;
  32
  33 @Provider
  34 @Produces({ MediaTypes.APPLICATION_YANG_DATA_XML, MediaType.APPLICATION_XML, MediaType.TEXT_XML })
  35 public final class XmlNormalizedNodeBodyWriter extends AbstractNormalizedNodeBodyWriter {
  36     @Override
  37     void writeData(final SchemaInferenceStack stack, final NormalizedNode data, final WriterParameters writerParameters,
  38             final FormatParameters format, final OutputStream out) throws IOException {
  39         final boolean isRoot;
  40         if (!stack.isEmpty()) {
  41             stack.exit();
  42             isRoot = false;
  43         } else {
  44             isRoot = true;
  45         }
  46
  47         final var xmlWriter = FormattableBodySupport.createXmlWriter(out, format);
  48         final var nnWriter = createNormalizedNodeWriter(xmlWriter, stack.toInference(), writerParameters);
  49         if (data instanceof MapEntryNode mapEntry) {
  50             // Restconf allows returning one list item. We need to wrap it
  51             // in map node in order to serialize it properly
  52             nnWriter.write(ImmutableNodes.newSystemMapBuilder()
  53                 .withNodeIdentifier(new NodeIdentifier(data.name().getNodeType()))
  54                 .addChild(mapEntry)
  55                 .build());
  56         } else if (isRoot) {
  57             if (data instanceof ContainerNode container && container.isEmpty()) {
  58                 writeEmptyDataNode(xmlWriter, container);
  59             } else {
  60                 writeAndWrapInDataNode(xmlWriter, nnWriter, data);
  61             }
  62         } else {
  63             nnWriter.write(data);
  64         }
  65         nnWriter.flush();
  66     }
  67
  68     private static RestconfNormalizedNodeWriter createNormalizedNodeWriter(final XMLStreamWriter xmlWriter,
  69             final Inference inference, final WriterParameters writerParameters) {
  70         return ParameterAwareNormalizedNodeWriter.forStreamWriter(
  71             XMLStreamNormalizedNodeStreamWriter.create(xmlWriter, inference),
  72             writerParameters.depth(), writerParameters.fields());
  73     }
  74
  75     private static void writeAndWrapInDataNode(final XMLStreamWriter xmlWriter,
  76             final RestconfNormalizedNodeWriter nnWriter, final NormalizedNode data) throws IOException {
  77         final QName nodeType = data.name().getNodeType();
  78         final String namespace = nodeType.getNamespace().toString();
  79         try {
  80             xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX, nodeType.getLocalName(), namespace);
  81             xmlWriter.writeDefaultNamespace(namespace);
  82             nnWriter.write(data);
  83             xmlWriter.writeEndElement();
  84             xmlWriter.flush();
  85         } catch (XMLStreamException e) {
  86             throw new IOException("Failed to write elements", e);
  87         }
  88     }
  89
  90     private static void writeEmptyDataNode(final XMLStreamWriter xmlWriter, final ContainerNode data)
  91             throws IOException {
  92         final QName nodeType = data.name().getNodeType();
  93         final String namespace = nodeType.getNamespace().toString();
  94         try {
  95             xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX, nodeType.getLocalName(), namespace);
  96             xmlWriter.writeDefaultNamespace(namespace);
  97             xmlWriter.writeEndElement();
  98             xmlWriter.flush();
  99         } catch (XMLStreamException e) {
 100             throw new IOException("Failed to write elements", e);
 101         }
 102     }
 103 }