restconf/restconf-nb-rfc8040/src/main/java/org/opendaylight/restconf/nb/rfc8040/jersey/providers/JsonNormalizedNodeBodyWriter.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 com.google.gson.stream.JsonWriter;
  11 import java.io.IOException;
  12 import java.io.OutputStream;
  13 import java.io.OutputStreamWriter;
  14 import java.lang.annotation.Annotation;
  15 import java.lang.reflect.Type;
  16 import java.nio.charset.StandardCharsets;
  17 import java.util.List;
  18 import java.util.Map;
  19 import java.util.Set;
  20 import java.util.stream.Collectors;
  21 import javax.ws.rs.Produces;
  22 import javax.ws.rs.WebApplicationException;
  23 import javax.ws.rs.core.MediaType;
  24 import javax.ws.rs.core.MultivaluedMap;
  25 import javax.ws.rs.ext.Provider;
  26 import org.opendaylight.restconf.common.context.InstanceIdentifierContext;
  27 import org.opendaylight.restconf.nb.rfc8040.DepthParam;
  28 import org.opendaylight.restconf.nb.rfc8040.MediaTypes;
  29 import org.opendaylight.restconf.nb.rfc8040.jersey.providers.api.RestconfNormalizedNodeWriter;
  30 import org.opendaylight.restconf.nb.rfc8040.legacy.NormalizedNodePayload;
  31 import org.opendaylight.yangtools.yang.common.QName;
  32 import org.opendaylight.yangtools.yang.common.XMLNamespace;
  33 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  34 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  35 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  36 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
  37 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  38 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  39 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  40 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactory;
  41 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactorySupplier;
  42 import org.opendaylight.yangtools.yang.data.codec.gson.JSONNormalizedNodeStreamWriter;
  43 import org.opendaylight.yangtools.yang.data.codec.gson.JsonWriterFactory;
  44 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
  45 import org.opendaylight.yangtools.yang.model.api.ActionDefinition;
  46 import org.opendaylight.yangtools.yang.model.api.Module;
  47 import org.opendaylight.yangtools.yang.model.api.RpcDefinition;
  48 import org.opendaylight.yangtools.yang.model.api.SchemaNode;
  49 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  50 import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier.Absolute;
  51 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack;
  52
  53 @Provider
  54 @Produces({ MediaTypes.APPLICATION_YANG_DATA_JSON, MediaType.APPLICATION_JSON })
  55 public class JsonNormalizedNodeBodyWriter extends AbstractNormalizedNodeBodyWriter {
  56     private static final int DEFAULT_INDENT_SPACES_NUM = 2;
  57
  58     @Override
  59     public void writeTo(final NormalizedNodePayload context,
  60                         final Class<?> type,
  61                         final Type genericType,
  62                         final Annotation[] annotations,
  63                         final MediaType mediaType,
  64                         final MultivaluedMap<String, Object> httpHeaders,
  65                         final OutputStream entityStream) throws IOException, WebApplicationException {
  66         final NormalizedNode data = context.getData();
  67         if (data == null) {
  68             return;
  69         }
  70
  71         @SuppressWarnings("unchecked")
  72         final InstanceIdentifierContext<SchemaNode> identifierCtx =
  73                 (InstanceIdentifierContext<SchemaNode>) context.getInstanceIdentifierContext();
  74         final SchemaInferenceStack stack = SchemaInferenceStack.of(identifierCtx.getSchemaContext());
  75         identifierCtx.getInstanceIdentifier().getPathArguments().stream()
  76                 .filter(arg -> !(arg instanceof YangInstanceIdentifier.NodeIdentifierWithPredicates))
  77                 .filter(arg -> !(arg instanceof YangInstanceIdentifier.AugmentationIdentifier))
  78                 .forEach(p -> stack.enterSchemaTree(p.getNodeType()));
  79         final SchemaPath path = stack.toSchemaPath();
  80         final var pretty = context.getWriterParameters().prettyPrint();
  81
  82         try (JsonWriter jsonWriter = createJsonWriter(entityStream, pretty == null ? false : pretty.value())) {
  83             jsonWriter.beginObject();
  84             writeNormalizedNode(jsonWriter, path, identifierCtx, data,
  85                     context.getWriterParameters().depth(), context.getWriterParameters().fields());
  86             jsonWriter.endObject();
  87             jsonWriter.flush();
  88         }
  89
  90         if (httpHeaders != null) {
  91             for (final Map.Entry<String, Object> entry : context.getNewHeaders().entrySet()) {
  92                 httpHeaders.add(entry.getKey(), entry.getValue());
  93             }
  94         }
  95     }
  96
  97     private static void writeNormalizedNode(final JsonWriter jsonWriter,
  98             final SchemaPath path, final InstanceIdentifierContext<SchemaNode> context, final NormalizedNode data,
  99             final DepthParam depth, final List<Set<QName>> fields) throws IOException {
 100         final RestconfNormalizedNodeWriter nnWriter;
 101
 102         if (context.getSchemaNode() instanceof RpcDefinition) {
 103             /*
 104              *  RpcDefinition is not supported as initial codec in JSONStreamWriter,
 105              *  so we need to emit initial output declaration..
 106              */
 107             final RpcDefinition rpc = (RpcDefinition) context.getSchemaNode();
 108             final SchemaPath rpcPath = SchemaPath.of(Absolute.of(rpc.getQName(), rpc.getOutput().getQName()));
 109             nnWriter = createNormalizedNodeWriter(context, rpcPath, jsonWriter, depth, fields);
 110             final Module module = context.getSchemaContext().findModule(data.getIdentifier().getNodeType().getModule())
 111                 .get();
 112             jsonWriter.name(module.getName() + ":output");
 113             jsonWriter.beginObject();
 114             writeChildren(nnWriter, (ContainerNode) data);
 115             jsonWriter.endObject();
 116         } else if (context.getSchemaNode() instanceof ActionDefinition) {
 117             /*
 118              *  ActionDefinition is not supported as initial codec in JSONStreamWriter,
 119              *  so we need to emit initial output declaration..
 120              */
 121             final ActionDefinition actDef = (ActionDefinition) context.getSchemaNode();
 122             final List<QName> qNames = context.getInstanceIdentifier().getPathArguments().stream()
 123                     .filter(arg -> !(arg instanceof YangInstanceIdentifier.NodeIdentifierWithPredicates))
 124                     .filter(arg -> !(arg instanceof YangInstanceIdentifier.AugmentationIdentifier))
 125                     .map(PathArgument::getNodeType)
 126                     .collect(Collectors.toList());
 127             qNames.add(actDef.getQName());
 128             qNames.add(actDef.getOutput().getQName());
 129             final SchemaPath actPath = SchemaPath.of(Absolute.of(qNames));
 130             nnWriter = createNormalizedNodeWriter(context, actPath, jsonWriter, depth, fields);
 131             final Module module = context.getSchemaContext().findModule(data.getIdentifier().getNodeType().getModule())
 132                 .get();
 133             jsonWriter.name(module.getName() + ":output");
 134             jsonWriter.beginObject();
 135             writeChildren(nnWriter, (ContainerNode) data);
 136             jsonWriter.endObject();
 137         } else {
 138             if (SchemaPath.ROOT.equals(path)) {
 139                 nnWriter = createNormalizedNodeWriter(context, path, jsonWriter, depth, fields);
 140             } else {
 141                 nnWriter = createNormalizedNodeWriter(context, path.getParent(), jsonWriter, depth, fields);
 142             }
 143
 144             if (data instanceof MapEntryNode) {
 145                 // Restconf allows returning one list item. We need to wrap it
 146                 // in map node in order to serialize it properly
 147                 nnWriter.write(ImmutableNodes.mapNodeBuilder(data.getIdentifier().getNodeType())
 148                     .withChild((MapEntryNode) data)
 149                     .build());
 150             } else {
 151                 nnWriter.write(data);
 152             }
 153         }
 154
 155         nnWriter.flush();
 156     }
 157
 158     private static void writeChildren(final RestconfNormalizedNodeWriter nnWriter, final ContainerNode data)
 159             throws IOException {
 160         for (final DataContainerChild child : data.body()) {
 161             nnWriter.write(child);
 162         }
 163     }
 164
 165     private static RestconfNormalizedNodeWriter createNormalizedNodeWriter(
 166             final InstanceIdentifierContext<SchemaNode> context, final SchemaPath path, final JsonWriter jsonWriter,
 167             final DepthParam depth, final List<Set<QName>> fields) {
 168
 169         final SchemaNode schema = context.getSchemaNode();
 170         final JSONCodecFactory codecs = getCodecFactory(context);
 171
 172         final NormalizedNodeStreamWriter streamWriter = JSONNormalizedNodeStreamWriter.createNestedWriter(
 173                 codecs, path, initialNamespaceFor(schema), jsonWriter);
 174
 175         return ParameterAwareNormalizedNodeWriter.forStreamWriter(streamWriter, depth, fields);
 176     }
 177
 178     private static XMLNamespace initialNamespaceFor(final SchemaNode schema) {
 179         if (schema instanceof RpcDefinition) {
 180             return schema.getQName().getNamespace();
 181         }
 182         // For top-level elements we always want to use namespace prefix, hence use a null initial namespace
 183         return null;
 184     }
 185
 186     private static JsonWriter createJsonWriter(final OutputStream entityStream, final boolean prettyPrint) {
 187         if (prettyPrint) {
 188             return JsonWriterFactory.createJsonWriter(
 189                     new OutputStreamWriter(entityStream, StandardCharsets.UTF_8), DEFAULT_INDENT_SPACES_NUM);
 190         }
 191         return JsonWriterFactory.createJsonWriter(new OutputStreamWriter(entityStream, StandardCharsets.UTF_8));
 192     }
 193
 194     private static JSONCodecFactory getCodecFactory(final InstanceIdentifierContext<?> context) {
 195         // TODO: Performance: Cache JSON Codec factory and schema context
 196         return JSONCodecFactorySupplier.RFC7951.getShared(context.getSchemaContext());
 197     }
 198 }