restconf/sal-rest-connector/src/main/java/org/opendaylight/netconf/sal/rest/impl/NormalizedNodeJsonBodyWriter.java

   1 /*
   2  * Copyright (c) 2014 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.netconf.sal.rest.impl;
   9
  10 import com.google.common.base.Optional;
  11 import com.google.gson.stream.JsonWriter;
  12 import java.io.IOException;
  13 import java.io.OutputStream;
  14 import java.io.OutputStreamWriter;
  15 import java.lang.annotation.Annotation;
  16 import java.lang.reflect.Type;
  17 import java.net.URI;
  18 import java.nio.charset.StandardCharsets;
  19 import javax.ws.rs.Produces;
  20 import javax.ws.rs.WebApplicationException;
  21 import javax.ws.rs.core.MediaType;
  22 import javax.ws.rs.core.MultivaluedMap;
  23 import javax.ws.rs.ext.MessageBodyWriter;
  24 import javax.ws.rs.ext.Provider;
  25 import org.opendaylight.netconf.sal.rest.api.Draft02;
  26 import org.opendaylight.netconf.sal.rest.api.RestconfNormalizedNodeWriter;
  27 import org.opendaylight.netconf.sal.rest.api.RestconfService;
  28 import org.opendaylight.netconf.sal.restconf.impl.InstanceIdentifierContext;
  29 import org.opendaylight.netconf.sal.restconf.impl.NormalizedNodeContext;
  30 import org.opendaylight.restconf.Draft11;
  31 import org.opendaylight.restconf.utils.RestconfConstants;
  32 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  33 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  34 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
  35 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  36 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  37 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  38 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactory;
  39 import org.opendaylight.yangtools.yang.data.codec.gson.JSONNormalizedNodeStreamWriter;
  40 import org.opendaylight.yangtools.yang.data.codec.gson.JsonWriterFactory;
  41 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
  42 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
  43 import org.opendaylight.yangtools.yang.model.api.RpcDefinition;
  44 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  45 import org.opendaylight.yangtools.yang.model.api.SchemaNode;
  46 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  47
  48 @Provider
  49 @Produces({ Draft02.MediaTypes.API + RestconfService.JSON, Draft02.MediaTypes.DATA + RestconfService.JSON,
  50         Draft02.MediaTypes.OPERATION + RestconfService.JSON,
  51         Draft11.MediaTypes.API + RestconfConstants.JSON, Draft11.MediaTypes.DATA + RestconfConstants.JSON,
  52         Draft11.MediaTypes.OPERATION + RestconfConstants.JSON, MediaType.APPLICATION_JSON })
  53 public class NormalizedNodeJsonBodyWriter implements MessageBodyWriter<NormalizedNodeContext> {
  54
  55     private static final int DEFAULT_INDENT_SPACES_NUM = 2;
  56
  57     @Override
  58     public boolean isWriteable(final Class<?> type, final Type genericType, final Annotation[] annotations, final MediaType mediaType) {
  59         return type.equals(NormalizedNodeContext.class);
  60     }
  61
  62     @Override
  63     public long getSize(final NormalizedNodeContext t, final Class<?> type, final Type genericType, final Annotation[] annotations, final MediaType mediaType) {
  64         return -1;
  65     }
  66
  67     @Override
  68     public void writeTo(final NormalizedNodeContext t, final Class<?> type, final Type genericType, final Annotation[] annotations,
  69             final MediaType mediaType, final MultivaluedMap<String, Object> httpHeaders, final OutputStream entityStream)
  70                     throws IOException, WebApplicationException {
  71         final NormalizedNode<?, ?> data = t.getData();
  72         if (data == null) {
  73             return;
  74         }
  75
  76         @SuppressWarnings("unchecked")
  77         final InstanceIdentifierContext<SchemaNode> context = (InstanceIdentifierContext<SchemaNode>) t.getInstanceIdentifierContext();
  78
  79         final SchemaPath path = context.getSchemaNode().getPath();
  80         final JsonWriter jsonWriter = createJsonWriter(entityStream, t.getWriterParameters().isPrettyPrint());
  81         jsonWriter.beginObject();
  82         writeNormalizedNode(jsonWriter,path,context,data, t.getWriterParameters().getDepth());
  83         jsonWriter.endObject();
  84         jsonWriter.flush();
  85     }
  86
  87     private void writeNormalizedNode(final JsonWriter jsonWriter, SchemaPath path,
  88             final InstanceIdentifierContext<SchemaNode> context, NormalizedNode<?, ?> data, final Optional<Integer> depth) throws
  89             IOException {
  90         final RestconfNormalizedNodeWriter nnWriter;
  91         if (SchemaPath.ROOT.equals(path)) {
  92             /*
  93              *  Creates writer without initialNs and we write children of root data container
  94              *  which is not visible in restconf
  95              */
  96             nnWriter = createNormalizedNodeWriter(context,path,jsonWriter, depth);
  97             writeChildren(nnWriter,(ContainerNode) data);
  98         } else if (context.getSchemaNode() instanceof RpcDefinition) {
  99             /*
 100              *  RpcDefinition is not supported as initial codec in JSONStreamWriter,
 101              *  so we need to emit initial output declaratation..
 102              */
 103             path = ((RpcDefinition) context.getSchemaNode()).getOutput().getPath();
 104             nnWriter = createNormalizedNodeWriter(context,path,jsonWriter, depth);
 105             jsonWriter.name("output");
 106             jsonWriter.beginObject();
 107             writeChildren(nnWriter, (ContainerNode) data);
 108             jsonWriter.endObject();
 109         } else {
 110             path = path.getParent();
 111
 112             if(data instanceof MapEntryNode) {
 113                 data = ImmutableNodes.mapNodeBuilder(data.getNodeType()).withChild(((MapEntryNode) data)).build();
 114             }
 115             nnWriter = createNormalizedNodeWriter(context,path,jsonWriter, depth);
 116             nnWriter.write(data);
 117         }
 118         nnWriter.flush();
 119     }
 120
 121     private void writeChildren(final RestconfNormalizedNodeWriter nnWriter, final ContainerNode data) throws IOException {
 122         for(final DataContainerChild<? extends PathArgument, ?> child : data.getValue()) {
 123             nnWriter.write(child);
 124         }
 125     }
 126
 127     private RestconfNormalizedNodeWriter createNormalizedNodeWriter(final InstanceIdentifierContext<SchemaNode> context,
 128             final SchemaPath path, final JsonWriter jsonWriter, final Optional<Integer> depth) {
 129
 130         final SchemaNode schema = context.getSchemaNode();
 131         final JSONCodecFactory codecs = getCodecFactory(context);
 132
 133         final URI initialNs;
 134         if ((schema instanceof DataSchemaNode)
 135                 && !((DataSchemaNode)schema).isAugmenting()
 136                 && !(schema instanceof SchemaContext)) {
 137             initialNs = schema.getQName().getNamespace();
 138         } else if (schema instanceof RpcDefinition) {
 139             initialNs = schema.getQName().getNamespace();
 140         } else {
 141             initialNs = null;
 142         }
 143         final NormalizedNodeStreamWriter streamWriter = JSONNormalizedNodeStreamWriter.createNestedWriter(codecs,path,initialNs,jsonWriter);
 144         if (depth.isPresent()) {
 145             return DepthAwareNormalizedNodeWriter.forStreamWriter(streamWriter, depth.get());
 146         } else {
 147             return RestconfDelegatingNormalizedNodeWriter.forStreamWriter(streamWriter);
 148         }
 149     }
 150
 151     private JsonWriter createJsonWriter(final OutputStream entityStream, final boolean prettyPrint) {
 152         if (prettyPrint) {
 153             return JsonWriterFactory.createJsonWriter(new OutputStreamWriter(entityStream, StandardCharsets.UTF_8),
 154                     DEFAULT_INDENT_SPACES_NUM);
 155         } else {
 156             return JsonWriterFactory.createJsonWriter(new OutputStreamWriter(entityStream, StandardCharsets.UTF_8));
 157         }
 158     }
 159
 160     private JSONCodecFactory getCodecFactory(final InstanceIdentifierContext<?> context) {
 161         // TODO: Performance: Cache JSON Codec factory and schema context
 162         return JSONCodecFactory.create(context.getSchemaContext());
 163     }
 164
 165 }