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.Draft16;
  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, Draft16.MediaTypes.DATA + RestconfConstants.JSON,
  51         MediaType.APPLICATION_JSON })
  52 public class NormalizedNodeJsonBodyWriter implements MessageBodyWriter<NormalizedNodeContext> {
  53
  54     private static final int DEFAULT_INDENT_SPACES_NUM = 2;
  55
  56     @Override
  57     public boolean isWriteable(final Class<?> type, final Type genericType, final Annotation[] annotations, final MediaType mediaType) {
  58         return type.equals(NormalizedNodeContext.class);
  59     }
  60
  61     @Override
  62     public long getSize(final NormalizedNodeContext t, final Class<?> type, final Type genericType, final Annotation[] annotations, final MediaType mediaType) {
  63         return -1;
  64     }
  65
  66     @Override
  67     public void writeTo(final NormalizedNodeContext t, final Class<?> type, final Type genericType, final Annotation[] annotations,
  68             final MediaType mediaType, final MultivaluedMap<String, Object> httpHeaders, final OutputStream entityStream)
  69                     throws IOException, WebApplicationException {
  70         final NormalizedNode<?, ?> data = t.getData();
  71         if (data == null) {
  72             return;
  73         }
  74
  75         @SuppressWarnings("unchecked")
  76         final InstanceIdentifierContext<SchemaNode> context = (InstanceIdentifierContext<SchemaNode>) t.getInstanceIdentifierContext();
  77
  78         final SchemaPath path = context.getSchemaNode().getPath();
  79         final JsonWriter jsonWriter = createJsonWriter(entityStream, t.getWriterParameters().isPrettyPrint());
  80         jsonWriter.beginObject();
  81         writeNormalizedNode(jsonWriter,path,context,data, t.getWriterParameters().getDepth());
  82         jsonWriter.endObject();
  83         jsonWriter.flush();
  84     }
  85
  86     private void writeNormalizedNode(final JsonWriter jsonWriter, SchemaPath path,
  87             final InstanceIdentifierContext<SchemaNode> context, NormalizedNode<?, ?> data, final Optional<Integer> depth) throws
  88             IOException {
  89         final RestconfNormalizedNodeWriter nnWriter;
  90         if (SchemaPath.ROOT.equals(path)) {
  91             /*
  92              *  Creates writer without initialNs and we write children of root data container
  93              *  which is not visible in restconf
  94              */
  95             nnWriter = createNormalizedNodeWriter(context,path,jsonWriter, depth);
  96             writeChildren(nnWriter,(ContainerNode) data);
  97         } else if (context.getSchemaNode() instanceof RpcDefinition) {
  98             /*
  99              *  RpcDefinition is not supported as initial codec in JSONStreamWriter,
 100              *  so we need to emit initial output declaratation..
 101              */
 102             path = ((RpcDefinition) context.getSchemaNode()).getOutput().getPath();
 103             nnWriter = createNormalizedNodeWriter(context,path,jsonWriter, depth);
 104             jsonWriter.name("output");
 105             jsonWriter.beginObject();
 106             writeChildren(nnWriter, (ContainerNode) data);
 107             jsonWriter.endObject();
 108         } else {
 109             path = path.getParent();
 110
 111             if(data instanceof MapEntryNode) {
 112                 data = ImmutableNodes.mapNodeBuilder(data.getNodeType()).withChild(((MapEntryNode) data)).build();
 113             }
 114             nnWriter = createNormalizedNodeWriter(context,path,jsonWriter, depth);
 115             nnWriter.write(data);
 116         }
 117         nnWriter.flush();
 118     }
 119
 120     private void writeChildren(final RestconfNormalizedNodeWriter nnWriter, final ContainerNode data) throws IOException {
 121         for(final DataContainerChild<? extends PathArgument, ?> child : data.getValue()) {
 122             nnWriter.write(child);
 123         }
 124     }
 125
 126     private RestconfNormalizedNodeWriter createNormalizedNodeWriter(final InstanceIdentifierContext<SchemaNode> context,
 127             final SchemaPath path, final JsonWriter jsonWriter, final Optional<Integer> depth) {
 128
 129         final SchemaNode schema = context.getSchemaNode();
 130         final JSONCodecFactory codecs = getCodecFactory(context);
 131
 132         final URI initialNs;
 133         if ((schema instanceof DataSchemaNode)
 134                 && !((DataSchemaNode)schema).isAugmenting()
 135                 && !(schema instanceof SchemaContext)) {
 136             initialNs = schema.getQName().getNamespace();
 137         } else if (schema instanceof RpcDefinition) {
 138             initialNs = schema.getQName().getNamespace();
 139         } else {
 140             initialNs = null;
 141         }
 142         final NormalizedNodeStreamWriter streamWriter = JSONNormalizedNodeStreamWriter.createNestedWriter(codecs,path,initialNs,jsonWriter);
 143         if (depth.isPresent()) {
 144             return DepthAwareNormalizedNodeWriter.forStreamWriter(streamWriter, depth.get());
 145         } else {
 146             return RestconfDelegatingNormalizedNodeWriter.forStreamWriter(streamWriter);
 147         }
 148     }
 149
 150     private JsonWriter createJsonWriter(final OutputStream entityStream, final boolean prettyPrint) {
 151         if (prettyPrint) {
 152             return JsonWriterFactory.createJsonWriter(new OutputStreamWriter(entityStream, StandardCharsets.UTF_8),
 153                     DEFAULT_INDENT_SPACES_NUM);
 154         } else {
 155             return JsonWriterFactory.createJsonWriter(new OutputStreamWriter(entityStream, StandardCharsets.UTF_8));
 156         }
 157     }
 158
 159     private JSONCodecFactory getCodecFactory(final InstanceIdentifierContext<?> context) {
 160         // TODO: Performance: Cache JSON Codec factory and schema context
 161         return JSONCodecFactory.create(context.getSchemaContext());
 162     }
 163
 164 }