restconf/restconf-nb-bierman02/src/main/java/org/opendaylight/netconf/sal/rest/impl/RestconfDocumentedExceptionMapper.java

   1 /*
   2  * Copyright (c) 2014 Brocade Communications 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.Preconditions;
  11 import com.google.common.collect.Iterables;
  12 import com.google.gson.stream.JsonWriter;
  13 import java.io.ByteArrayOutputStream;
  14 import java.io.IOException;
  15 import java.io.OutputStreamWriter;
  16 import java.io.UnsupportedEncodingException;
  17 import java.net.URI;
  18 import java.nio.charset.StandardCharsets;
  19 import java.util.ArrayList;
  20 import java.util.List;
  21 import javax.ws.rs.core.Context;
  22 import javax.ws.rs.core.HttpHeaders;
  23 import javax.ws.rs.core.MediaType;
  24 import javax.ws.rs.core.Response;
  25 import javax.ws.rs.ext.ExceptionMapper;
  26 import javax.ws.rs.ext.Provider;
  27 import javax.xml.XMLConstants;
  28 import javax.xml.stream.FactoryConfigurationError;
  29 import javax.xml.stream.XMLOutputFactory;
  30 import javax.xml.stream.XMLStreamException;
  31 import javax.xml.stream.XMLStreamWriter;
  32 import org.opendaylight.netconf.sal.rest.api.Draft02;
  33 import org.opendaylight.netconf.sal.restconf.impl.ControllerContext;
  34 import org.opendaylight.restconf.common.context.InstanceIdentifierContext;
  35 import org.opendaylight.restconf.common.context.NormalizedNodeContext;
  36 import org.opendaylight.restconf.common.errors.RestconfDocumentedException;
  37 import org.opendaylight.restconf.common.errors.RestconfError;
  38 import org.opendaylight.yangtools.yang.common.QName;
  39 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  40 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
  41 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  42 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  43 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
  44 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  45 import org.opendaylight.yangtools.yang.data.api.schema.MapNode;
  46 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  47 import org.opendaylight.yangtools.yang.data.api.schema.stream.ForwardingNormalizedNodeStreamWriter;
  48 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  49 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeWriter;
  50 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactorySupplier;
  51 import org.opendaylight.yangtools.yang.data.codec.gson.JSONNormalizedNodeStreamWriter;
  52 import org.opendaylight.yangtools.yang.data.codec.gson.JsonWriterFactory;
  53 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  54 import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
  55 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
  56 import org.opendaylight.yangtools.yang.data.impl.schema.builder.api.CollectionNodeBuilder;
  57 import org.opendaylight.yangtools.yang.data.impl.schema.builder.api.DataContainerNodeBuilder;
  58 import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
  59 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
  60 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
  61 import org.opendaylight.yangtools.yang.model.api.LeafSchemaNode;
  62 import org.opendaylight.yangtools.yang.model.api.ListSchemaNode;
  63 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  64 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  65 import org.slf4j.Logger;
  66 import org.slf4j.LoggerFactory;
  67
  68 /**
  69  * This class defines an ExceptionMapper that handles RestconfDocumentedExceptions thrown by resource implementations
  70  * and translates appropriately to restconf error response as defined in the RESTCONF RFC draft.
  71  *
  72  * @author Thomas Pantelis
  73  */
  74 @Provider
  75 public class RestconfDocumentedExceptionMapper implements ExceptionMapper<RestconfDocumentedException> {
  76
  77     private static final Logger LOG = LoggerFactory.getLogger(RestconfDocumentedExceptionMapper.class);
  78
  79     private static final XMLOutputFactory XML_FACTORY;
  80
  81     static {
  82         XML_FACTORY = XMLOutputFactory.newFactory();
  83         XML_FACTORY.setProperty(XMLOutputFactory.IS_REPAIRING_NAMESPACES, true);
  84     }
  85
  86     @Context
  87     private HttpHeaders headers;
  88
  89     private final ControllerContext controllerContext;
  90
  91     public RestconfDocumentedExceptionMapper(final ControllerContext controllerContext) {
  92         this.controllerContext = Preconditions.checkNotNull(controllerContext);
  93     }
  94
  95     @Override
  96     public Response toResponse(final RestconfDocumentedException exception) {
  97
  98         LOG.debug("In toResponse: {}", exception.getMessage());
  99
 100         final List<MediaType> mediaTypeList = new ArrayList<>();
 101         if (headers.getMediaType() != null) {
 102             mediaTypeList.add(headers.getMediaType());
 103         }
 104
 105         mediaTypeList.addAll(headers.getAcceptableMediaTypes());
 106         final MediaType mediaType = mediaTypeList.stream().filter(type -> !type.equals(MediaType.WILDCARD_TYPE))
 107                 .findFirst().orElse(MediaType.APPLICATION_JSON_TYPE);
 108
 109         LOG.debug("Using MediaType: {}", mediaType);
 110
 111         final List<RestconfError> errors = exception.getErrors();
 112         if (errors.isEmpty()) {
 113             // We don't actually want to send any content but, if we don't set any content here,
 114             // the tomcat front-end will send back an html error report. To prevent that, set a
 115             // single space char in the entity.
 116
 117             return Response.status(exception.getStatus()).type(MediaType.TEXT_PLAIN_TYPE).entity(" ").build();
 118         }
 119
 120         final int status = errors.iterator().next().getErrorTag().getStatusCode();
 121
 122         final DataNodeContainer errorsSchemaNode =
 123                 (DataNodeContainer) controllerContext.getRestconfModuleErrorsSchemaNode();
 124
 125         if (errorsSchemaNode == null) {
 126             return Response.status(status).type(MediaType.TEXT_PLAIN_TYPE).entity(exception.getMessage()).build();
 127         }
 128
 129         Preconditions.checkState(errorsSchemaNode instanceof ContainerSchemaNode,
 130                 "Found Errors SchemaNode isn't ContainerNode");
 131         final DataContainerNodeBuilder<NodeIdentifier, ContainerNode> errContBuild =
 132                 Builders.containerBuilder((ContainerSchemaNode) errorsSchemaNode);
 133
 134         final List<DataSchemaNode> schemaList = ControllerContext.findInstanceDataChildrenByName(errorsSchemaNode,
 135                 Draft02.RestConfModule.ERROR_LIST_SCHEMA_NODE);
 136         final DataSchemaNode errListSchemaNode = Iterables.getFirst(schemaList, null);
 137         Preconditions.checkState(
 138                 errListSchemaNode instanceof ListSchemaNode, "Found Error SchemaNode isn't ListSchemaNode");
 139         final CollectionNodeBuilder<MapEntryNode, MapNode> listErorsBuilder = Builders
 140                 .mapBuilder((ListSchemaNode) errListSchemaNode);
 141
 142
 143         for (final RestconfError error : errors) {
 144             listErorsBuilder.withChild(toErrorEntryNode(error, errListSchemaNode));
 145         }
 146         errContBuild.withChild(listErorsBuilder.build());
 147
 148         final NormalizedNodeContext errContext =  new NormalizedNodeContext(new InstanceIdentifierContext<>(null,
 149                 (DataSchemaNode) errorsSchemaNode, null, controllerContext.getGlobalSchema()), errContBuild.build());
 150
 151         Object responseBody;
 152         if (mediaType.getSubtype().endsWith("json")) {
 153             responseBody = toJsonResponseBody(errContext, errorsSchemaNode);
 154         } else {
 155             responseBody = toXMLResponseBody(errContext, errorsSchemaNode);
 156         }
 157
 158         return Response.status(status).type(mediaType).entity(responseBody).build();
 159     }
 160
 161     private static MapEntryNode toErrorEntryNode(final RestconfError error, final DataSchemaNode errListSchemaNode) {
 162         Preconditions.checkArgument(errListSchemaNode instanceof ListSchemaNode,
 163                 "errListSchemaNode has to be of type ListSchemaNode");
 164         final ListSchemaNode listStreamSchemaNode = (ListSchemaNode) errListSchemaNode;
 165         final DataContainerNodeBuilder<NodeIdentifierWithPredicates, MapEntryNode> errNodeValues = Builders
 166                 .mapEntryBuilder(listStreamSchemaNode);
 167
 168         List<DataSchemaNode> lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 169                 listStreamSchemaNode, "error-type");
 170         final DataSchemaNode errTypSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 171         Preconditions.checkState(errTypSchemaNode instanceof LeafSchemaNode);
 172         errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errTypSchemaNode)
 173                 .withValue(error.getErrorType().getErrorTypeTag()).build());
 174
 175         lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 176                 listStreamSchemaNode, "error-tag");
 177         final DataSchemaNode errTagSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 178         Preconditions.checkState(errTagSchemaNode instanceof LeafSchemaNode);
 179         errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errTagSchemaNode)
 180                 .withValue(error.getErrorTag().getTagValue()).build());
 181
 182         if (error.getErrorAppTag() != null) {
 183             lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 184                     listStreamSchemaNode, "error-app-tag");
 185             final DataSchemaNode errAppTagSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 186             Preconditions.checkState(errAppTagSchemaNode instanceof LeafSchemaNode);
 187             errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errAppTagSchemaNode)
 188                     .withValue(error.getErrorAppTag()).build());
 189         }
 190
 191         lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 192                 listStreamSchemaNode, "error-message");
 193         final DataSchemaNode errMsgSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 194         Preconditions.checkState(errMsgSchemaNode instanceof LeafSchemaNode);
 195         errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errMsgSchemaNode)
 196                 .withValue(error.getErrorMessage()).build());
 197
 198         if (error.getErrorInfo() != null) {
 199             // Oddly, error-info is defined as an empty container in the restconf yang. Apparently the
 200             // intention is for implementors to define their own data content so we'll just treat it as a leaf
 201             // with string data.
 202             errNodeValues.withChild(ImmutableNodes.leafNode(Draft02.RestConfModule.ERROR_INFO_QNAME,
 203                     error.getErrorInfo()));
 204         }
 205
 206         // TODO : find how could we add possible "error-path"
 207
 208         return errNodeValues.build();
 209     }
 210
 211     private static Object toJsonResponseBody(final NormalizedNodeContext errorsNode,
 212                                              final DataNodeContainer errorsSchemaNode) {
 213         final ByteArrayOutputStream outStream = new ByteArrayOutputStream();
 214         NormalizedNode<?, ?> data = errorsNode.getData();
 215         final InstanceIdentifierContext<?> context = errorsNode.getInstanceIdentifierContext();
 216         final DataSchemaNode schema = (DataSchemaNode) context.getSchemaNode();
 217
 218         SchemaPath path = context.getSchemaNode().getPath();
 219         final OutputStreamWriter outputWriter = new OutputStreamWriter(outStream, StandardCharsets.UTF_8);
 220         if (data == null) {
 221             throw new RestconfDocumentedException(Response.Status.NOT_FOUND);
 222         }
 223
 224         boolean isDataRoot = false;
 225         URI initialNs = null;
 226         if (SchemaPath.ROOT.equals(path)) {
 227             isDataRoot = true;
 228         } else {
 229             path = path.getParent();
 230             // FIXME: Add proper handling of reading root.
 231         }
 232         if (!schema.isAugmenting() && !(schema instanceof SchemaContext)) {
 233             initialNs = schema.getQName().getNamespace();
 234         }
 235
 236         final JsonWriter jsonWriter = JsonWriterFactory.createJsonWriter(outputWriter);
 237         final NormalizedNodeStreamWriter jsonStreamWriter = JSONNormalizedNodeStreamWriter.createExclusiveWriter(
 238             JSONCodecFactorySupplier.DRAFT_LHOTKA_NETMOD_YANG_JSON_02.getShared(context.getSchemaContext()), path,
 239             initialNs, jsonWriter);
 240
 241         // We create a delegating writer to special-case error-info as error-info is defined as an empty
 242         // container in the restconf yang schema but we create a leaf node so we can output it. The delegate
 243         // stream writer validates the node type against the schema and thus will expect a LeafSchemaNode but
 244         // the schema has a ContainerSchemaNode so, to avoid an error, we override the leafNode behavior
 245         // for error-info.
 246         final NormalizedNodeStreamWriter streamWriter = new ForwardingNormalizedNodeStreamWriter() {
 247             @Override
 248             protected NormalizedNodeStreamWriter delegate() {
 249                 return jsonStreamWriter;
 250             }
 251
 252             @Override
 253             public void leafNode(final NodeIdentifier name, final Object value) throws IOException {
 254                 if (name.getNodeType().equals(Draft02.RestConfModule.ERROR_INFO_QNAME)) {
 255                     jsonWriter.name(Draft02.RestConfModule.ERROR_INFO_QNAME.getLocalName());
 256                     jsonWriter.value(value.toString());
 257                 } else {
 258                     super.leafNode(name, value);
 259                 }
 260             }
 261         };
 262
 263         final NormalizedNodeWriter nnWriter = NormalizedNodeWriter.forStreamWriter(streamWriter);
 264         try {
 265             if (isDataRoot) {
 266                 writeDataRoot(outputWriter,nnWriter,(ContainerNode) data);
 267             } else {
 268                 if (data instanceof MapEntryNode) {
 269                     data = ImmutableNodes.mapNodeBuilder(data.getNodeType()).withChild((MapEntryNode) data).build();
 270                 }
 271                 nnWriter.write(data);
 272             }
 273             nnWriter.flush();
 274             outputWriter.flush();
 275         } catch (final IOException e) {
 276             LOG.warn("Error writing error response body", e);
 277         }
 278
 279         try {
 280             return outStream.toString(StandardCharsets.UTF_8.name());
 281         } catch (UnsupportedEncodingException e) {
 282             // Shouldn't happen
 283             return "Failure encoding error response: " + e;
 284         }
 285     }
 286
 287     private static Object toXMLResponseBody(final NormalizedNodeContext errorsNode,
 288                                             final DataNodeContainer errorsSchemaNode) {
 289         final InstanceIdentifierContext<?> pathContext = errorsNode.getInstanceIdentifierContext();
 290         final ByteArrayOutputStream outStream = new ByteArrayOutputStream();
 291
 292         final XMLStreamWriter xmlWriter;
 293         try {
 294             xmlWriter = XML_FACTORY.createXMLStreamWriter(outStream, StandardCharsets.UTF_8.name());
 295         } catch (final XMLStreamException | FactoryConfigurationError e) {
 296             throw new IllegalStateException(e);
 297         }
 298         NormalizedNode<?, ?> data = errorsNode.getData();
 299         SchemaPath schemaPath = pathContext.getSchemaNode().getPath();
 300
 301         boolean isDataRoot = false;
 302         if (SchemaPath.ROOT.equals(schemaPath)) {
 303             isDataRoot = true;
 304         } else {
 305             schemaPath = schemaPath.getParent();
 306         }
 307
 308         final NormalizedNodeStreamWriter xmlStreamWriter = XMLStreamNormalizedNodeStreamWriter.create(xmlWriter,
 309                 pathContext.getSchemaContext(), schemaPath);
 310
 311         // We create a delegating writer to special-case error-info as error-info is defined as an empty
 312         // container in the restconf yang schema but we create a leaf node so we can output it. The delegate
 313         // stream writer validates the node type against the schema and thus will expect a LeafSchemaNode but
 314         // the schema has a ContainerSchemaNode so, to avoid an error, we override the leafNode behavior
 315         // for error-info.
 316         final NormalizedNodeStreamWriter streamWriter = new ForwardingNormalizedNodeStreamWriter() {
 317             @Override
 318             protected NormalizedNodeStreamWriter delegate() {
 319                 return xmlStreamWriter;
 320             }
 321
 322             @Override
 323             public void leafNode(final NodeIdentifier name, final Object value) throws IOException {
 324                 if (name.getNodeType().equals(Draft02.RestConfModule.ERROR_INFO_QNAME)) {
 325                     String ns = Draft02.RestConfModule.ERROR_INFO_QNAME.getNamespace().toString();
 326                     try {
 327                         xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX,
 328                                 Draft02.RestConfModule.ERROR_INFO_QNAME.getLocalName(), ns);
 329                         xmlWriter.writeCharacters(value.toString());
 330                         xmlWriter.writeEndElement();
 331                     } catch (XMLStreamException e) {
 332                         throw new IOException("Error writing error-info", e);
 333                     }
 334                 } else {
 335                     super.leafNode(name, value);
 336                 }
 337             }
 338         };
 339
 340         final NormalizedNodeWriter nnWriter = NormalizedNodeWriter.forStreamWriter(streamWriter);
 341         try {
 342             if (isDataRoot) {
 343                 writeRootElement(xmlWriter, nnWriter, (ContainerNode) data);
 344             } else {
 345                 if (data instanceof MapEntryNode) {
 346                     // Restconf allows returning one list item. We need to wrap it
 347                     // in map node in order to serialize it properly
 348                     data = ImmutableNodes.mapNodeBuilder(data.getNodeType()).addChild((MapEntryNode) data).build();
 349                 }
 350                 nnWriter.write(data);
 351                 nnWriter.flush();
 352             }
 353         } catch (final IOException e) {
 354             LOG.warn("Error writing error response body.", e);
 355         }
 356
 357         try {
 358             return outStream.toString(StandardCharsets.UTF_8.name());
 359         } catch (UnsupportedEncodingException e) {
 360             // Shouldn't happen
 361             return "Failure encoding error response: " + e;
 362         }
 363     }
 364
 365     private static void writeRootElement(final XMLStreamWriter xmlWriter, final NormalizedNodeWriter nnWriter,
 366                                          final ContainerNode data) throws IOException {
 367         final QName name = SchemaContext.NAME;
 368         try {
 369             xmlWriter.writeStartElement(name.getNamespace().toString(), name.getLocalName());
 370             for (final DataContainerChild<? extends PathArgument, ?> child : data.getValue()) {
 371                 nnWriter.write(child);
 372             }
 373             nnWriter.flush();
 374             xmlWriter.writeEndElement();
 375             xmlWriter.flush();
 376         } catch (final XMLStreamException e) {
 377             throw new IOException("Failed to write elements", e);
 378         }
 379     }
 380
 381     private static void writeDataRoot(final OutputStreamWriter outputWriter, final NormalizedNodeWriter nnWriter,
 382                                       final ContainerNode data) throws IOException {
 383         for (final DataContainerChild<? extends PathArgument, ?> child : data.getValue()) {
 384             nnWriter.write(child);
 385             nnWriter.flush();
 386         }
 387     }
 388 }