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
   9 package org.opendaylight.netconf.sal.rest.impl;
  10
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.base.Throwables;
  13 import com.google.common.collect.Iterables;
  14 import com.google.gson.stream.JsonWriter;
  15 import java.io.ByteArrayOutputStream;
  16 import java.io.IOException;
  17 import java.io.OutputStreamWriter;
  18 import java.net.URI;
  19 import java.nio.charset.StandardCharsets;
  20 import java.util.Iterator;
  21 import java.util.List;
  22 import javax.ws.rs.core.Context;
  23 import javax.ws.rs.core.HttpHeaders;
  24 import javax.ws.rs.core.MediaType;
  25 import javax.ws.rs.core.Response;
  26 import javax.ws.rs.ext.ExceptionMapper;
  27 import javax.ws.rs.ext.Provider;
  28 import javax.xml.XMLConstants;
  29 import javax.xml.stream.FactoryConfigurationError;
  30 import javax.xml.stream.XMLOutputFactory;
  31 import javax.xml.stream.XMLStreamException;
  32 import javax.xml.stream.XMLStreamWriter;
  33 import org.opendaylight.netconf.sal.rest.api.Draft02;
  34 import org.opendaylight.netconf.sal.restconf.impl.ControllerContext;
  35 import org.opendaylight.netconf.sal.restconf.impl.RestconfDocumentedException;
  36 import org.opendaylight.netconf.sal.restconf.impl.RestconfError;
  37 import org.opendaylight.restconf.common.context.InstanceIdentifierContext;
  38 import org.opendaylight.restconf.common.context.NormalizedNodeContext;
  39 import org.opendaylight.yangtools.yang.common.QName;
  40 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
  41 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
  42 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
  43 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
  44 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
  45 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  46 import org.opendaylight.yangtools.yang.data.api.schema.MapNode;
  47 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  48 import org.opendaylight.yangtools.yang.data.api.schema.stream.ForwardingNormalizedNodeStreamWriter;
  49 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  50 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeWriter;
  51 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactory;
  52 import org.opendaylight.yangtools.yang.data.codec.gson.JSONNormalizedNodeStreamWriter;
  53 import org.opendaylight.yangtools.yang.data.codec.gson.JsonWriterFactory;
  54 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  55 import org.opendaylight.yangtools.yang.data.impl.schema.Builders;
  56 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
  57 import org.opendaylight.yangtools.yang.data.impl.schema.builder.api.CollectionNodeBuilder;
  58 import org.opendaylight.yangtools.yang.data.impl.schema.builder.api.DataContainerNodeAttrBuilder;
  59 import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
  60 import org.opendaylight.yangtools.yang.model.api.DataNodeContainer;
  61 import org.opendaylight.yangtools.yang.model.api.DataSchemaNode;
  62 import org.opendaylight.yangtools.yang.model.api.LeafSchemaNode;
  63 import org.opendaylight.yangtools.yang.model.api.ListSchemaNode;
  64 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  65 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  66 import org.slf4j.Logger;
  67 import org.slf4j.LoggerFactory;
  68
  69 /**
  70  * This class defines an ExceptionMapper that handles RestconfDocumentedExceptions thrown by resource implementations
  71  * and translates appropriately to restconf error response as defined in the RESTCONF RFC draft.
  72  *
  73  * @author Thomas Pantelis
  74  */
  75 @Provider
  76 public class RestconfDocumentedExceptionMapper implements ExceptionMapper<RestconfDocumentedException> {
  77
  78     private static final Logger LOG = LoggerFactory.getLogger(RestconfDocumentedExceptionMapper.class);
  79
  80     private static final XMLOutputFactory XML_FACTORY;
  81
  82     static {
  83         XML_FACTORY = XMLOutputFactory.newFactory();
  84         XML_FACTORY.setProperty(XMLOutputFactory.IS_REPAIRING_NAMESPACES, true);
  85     }
  86
  87     @Context
  88     private HttpHeaders headers;
  89
  90     @Override
  91     public Response toResponse(final RestconfDocumentedException exception) {
  92
  93         LOG.debug("In toResponse: {}", exception.getMessage());
  94
  95         final List<MediaType> accepts = headers.getAcceptableMediaTypes();
  96         accepts.remove(MediaType.WILDCARD_TYPE);
  97
  98         LOG.debug("Accept headers: {}", accepts);
  99
 100         final MediaType mediaType;
 101         if (accepts != null && accepts.size() > 0) {
 102             mediaType = accepts.get(0); // just pick the first one
 103         } else {
 104             // Default to the content type if there's no Accept header
 105             mediaType = MediaType.APPLICATION_JSON_TYPE;
 106         }
 107
 108         LOG.debug("Using MediaType: {}", mediaType);
 109
 110         final List<RestconfError> errors = exception.getErrors();
 111         if (errors.isEmpty()) {
 112             // We don't actually want to send any content but, if we don't set any content here,
 113             // the tomcat front-end will send back an html error report. To prevent that, set a
 114             // single space char in the entity.
 115
 116             return Response.status(exception.getStatus()).type(MediaType.TEXT_PLAIN_TYPE).entity(" ").build();
 117         }
 118
 119         final int status = errors.iterator().next().getErrorTag().getStatusCode();
 120
 121         final ControllerContext context = ControllerContext.getInstance();
 122         final DataNodeContainer errorsSchemaNode = (DataNodeContainer) context.getRestconfModuleErrorsSchemaNode();
 123
 124         if (errorsSchemaNode == null) {
 125             return Response.status(status).type(MediaType.TEXT_PLAIN_TYPE).entity(exception.getMessage()).build();
 126         }
 127
 128         Preconditions.checkState(errorsSchemaNode instanceof ContainerSchemaNode,
 129                 "Found Errors SchemaNode isn't ContainerNode");
 130         final DataContainerNodeAttrBuilder<NodeIdentifier, ContainerNode> errContBuild =
 131                 Builders.containerBuilder((ContainerSchemaNode) errorsSchemaNode);
 132
 133         final List<DataSchemaNode> schemaList = ControllerContext.findInstanceDataChildrenByName(errorsSchemaNode,
 134                 Draft02.RestConfModule.ERROR_LIST_SCHEMA_NODE);
 135         final DataSchemaNode errListSchemaNode = Iterables.getFirst(schemaList, null);
 136         Preconditions.checkState(
 137                 errListSchemaNode instanceof ListSchemaNode, "Found Error SchemaNode isn't ListSchemaNode");
 138         final CollectionNodeBuilder<MapEntryNode, MapNode> listErorsBuilder = Builders
 139                 .mapBuilder((ListSchemaNode) errListSchemaNode);
 140
 141
 142         for (final RestconfError error : errors) {
 143             listErorsBuilder.withChild(toErrorEntryNode(error, errListSchemaNode));
 144         }
 145         errContBuild.withChild(listErorsBuilder.build());
 146
 147         final NormalizedNodeContext errContext =  new NormalizedNodeContext(new InstanceIdentifierContext<>(null,
 148                 (DataSchemaNode) errorsSchemaNode, null, context.getGlobalSchema()), errContBuild.build());
 149
 150         Object responseBody;
 151         if (mediaType.getSubtype().endsWith("json")) {
 152             responseBody = toJsonResponseBody(errContext, errorsSchemaNode);
 153         } else {
 154             responseBody = toXMLResponseBody(errContext, errorsSchemaNode);
 155         }
 156
 157         return Response.status(status).type(mediaType).entity(responseBody).build();
 158     }
 159
 160     private static MapEntryNode toErrorEntryNode(final RestconfError error, final DataSchemaNode errListSchemaNode) {
 161         Preconditions.checkArgument(errListSchemaNode instanceof ListSchemaNode,
 162                 "errListSchemaNode has to be of type ListSchemaNode");
 163         final ListSchemaNode listStreamSchemaNode = (ListSchemaNode) errListSchemaNode;
 164         final DataContainerNodeAttrBuilder<NodeIdentifierWithPredicates, MapEntryNode> errNodeValues = Builders
 165                 .mapEntryBuilder(listStreamSchemaNode);
 166
 167         List<DataSchemaNode> lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 168                 listStreamSchemaNode, "error-type");
 169         final DataSchemaNode errTypSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 170         Preconditions.checkState(errTypSchemaNode instanceof LeafSchemaNode);
 171         errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errTypSchemaNode)
 172                 .withValue(error.getErrorType().getErrorTypeTag()).build());
 173
 174         lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 175                 listStreamSchemaNode, "error-tag");
 176         final DataSchemaNode errTagSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 177         Preconditions.checkState(errTagSchemaNode instanceof LeafSchemaNode);
 178         errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errTagSchemaNode)
 179                 .withValue(error.getErrorTag().getTagValue()).build());
 180
 181         if (error.getErrorAppTag() != null) {
 182             lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 183                     listStreamSchemaNode, "error-app-tag");
 184             final DataSchemaNode errAppTagSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 185             Preconditions.checkState(errAppTagSchemaNode instanceof LeafSchemaNode);
 186             errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errAppTagSchemaNode)
 187                     .withValue(error.getErrorAppTag()).build());
 188         }
 189
 190         lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 191                 listStreamSchemaNode, "error-message");
 192         final DataSchemaNode errMsgSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 193         Preconditions.checkState(errMsgSchemaNode instanceof LeafSchemaNode);
 194         errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errMsgSchemaNode)
 195                 .withValue(error.getErrorMessage()).build());
 196
 197         if (error.getErrorInfo() != null) {
 198             // Oddly, error-info is defined as an empty container in the restconf yang. Apparently the
 199             // intention is for implementors to define their own data content so we'll just treat it as a leaf
 200             // with string data.
 201             errNodeValues.withChild(ImmutableNodes.leafNode(Draft02.RestConfModule.ERROR_INFO_QNAME,
 202                     error.getErrorInfo()));
 203         }
 204
 205         // TODO : find how could we add possible "error-path"
 206
 207         return errNodeValues.build();
 208     }
 209
 210     private static Object toJsonResponseBody(final NormalizedNodeContext errorsNode,
 211                                              final DataNodeContainer errorsSchemaNode) {
 212         final ByteArrayOutputStream outStream = new ByteArrayOutputStream();
 213         NormalizedNode<?, ?> data = errorsNode.getData();
 214         final InstanceIdentifierContext<?> context = errorsNode.getInstanceIdentifierContext();
 215         final DataSchemaNode schema = (DataSchemaNode) context.getSchemaNode();
 216
 217         SchemaPath path = context.getSchemaNode().getPath();
 218         final OutputStreamWriter outputWriter = new OutputStreamWriter(outStream, StandardCharsets.UTF_8);
 219         if (data == null) {
 220             throw new RestconfDocumentedException(Response.Status.NOT_FOUND);
 221         }
 222
 223         boolean isDataRoot = false;
 224         URI initialNs = null;
 225         if (SchemaPath.ROOT.equals(path)) {
 226             isDataRoot = true;
 227         } else {
 228             path = path.getParent();
 229             // FIXME: Add proper handling of reading root.
 230         }
 231         if (!schema.isAugmenting() && !(schema instanceof SchemaContext)) {
 232             initialNs = schema.getQName().getNamespace();
 233         }
 234
 235         final JsonWriter jsonWriter = JsonWriterFactory.createJsonWriter(outputWriter);
 236         final NormalizedNodeStreamWriter jsonStreamWriter = JSONNormalizedNodeStreamWriter.createExclusiveWriter(
 237                 JSONCodecFactory.getShared(context.getSchemaContext()), path, initialNs, jsonWriter);
 238
 239         // We create a delegating writer to special-case error-info as error-info is defined as an empty
 240         // container in the restconf yang schema but we create a leaf node so we can output it. The delegate
 241         // stream writer validates the node type against the schema and thus will expect a LeafSchemaNode but
 242         // the schema has a ContainerSchemaNode so, to avoid an error, we override the leafNode behavior
 243         // for error-info.
 244         final NormalizedNodeStreamWriter streamWriter = new ForwardingNormalizedNodeStreamWriter() {
 245             @Override
 246             protected NormalizedNodeStreamWriter delegate() {
 247                 return jsonStreamWriter;
 248             }
 249
 250             @Override
 251             public void leafNode(final NodeIdentifier name, final Object value) throws IOException {
 252                 if (name.getNodeType().equals(Draft02.RestConfModule.ERROR_INFO_QNAME)) {
 253                     jsonWriter.name(Draft02.RestConfModule.ERROR_INFO_QNAME.getLocalName());
 254                     jsonWriter.value(value.toString());
 255                 } else {
 256                     super.leafNode(name, value);
 257                 }
 258             }
 259         };
 260
 261         final NormalizedNodeWriter nnWriter = NormalizedNodeWriter.forStreamWriter(streamWriter);
 262         try {
 263             if (isDataRoot) {
 264                 writeDataRoot(outputWriter,nnWriter,(ContainerNode) data);
 265             } else {
 266                 if (data instanceof MapEntryNode) {
 267                     data = ImmutableNodes.mapNodeBuilder(data.getNodeType()).withChild((MapEntryNode) data).build();
 268                 }
 269                 nnWriter.write(data);
 270             }
 271             nnWriter.flush();
 272             outputWriter.flush();
 273         } catch (final IOException e) {
 274             LOG.warn("Error writing error response body", e);
 275         }
 276
 277         return outStream.toString();
 278
 279     }
 280
 281     private static Object toXMLResponseBody(final NormalizedNodeContext errorsNode,
 282                                             final DataNodeContainer errorsSchemaNode) {
 283         final InstanceIdentifierContext<?> pathContext = errorsNode.getInstanceIdentifierContext();
 284         final ByteArrayOutputStream outStream = new ByteArrayOutputStream();
 285
 286         final XMLStreamWriter xmlWriter;
 287         try {
 288             xmlWriter = XML_FACTORY.createXMLStreamWriter(outStream, StandardCharsets.UTF_8.name());
 289         } catch (final XMLStreamException e) {
 290             throw new IllegalStateException(e);
 291         } catch (final FactoryConfigurationError e) {
 292             throw new IllegalStateException(e);
 293         }
 294         NormalizedNode<?, ?> data = errorsNode.getData();
 295         SchemaPath schemaPath = pathContext.getSchemaNode().getPath();
 296
 297         boolean isDataRoot = false;
 298         if (SchemaPath.ROOT.equals(schemaPath)) {
 299             isDataRoot = true;
 300         } else {
 301             schemaPath = schemaPath.getParent();
 302         }
 303
 304         final NormalizedNodeStreamWriter xmlStreamWriter = XMLStreamNormalizedNodeStreamWriter.create(xmlWriter,
 305                 pathContext.getSchemaContext(), schemaPath);
 306
 307         // We create a delegating writer to special-case error-info as error-info is defined as an empty
 308         // container in the restconf yang schema but we create a leaf node so we can output it. The delegate
 309         // stream writer validates the node type against the schema and thus will expect a LeafSchemaNode but
 310         // the schema has a ContainerSchemaNode so, to avoid an error, we override the leafNode behavior
 311         // for error-info.
 312         final NormalizedNodeStreamWriter streamWriter = new ForwardingNormalizedNodeStreamWriter() {
 313             @Override
 314             protected NormalizedNodeStreamWriter delegate() {
 315                 return xmlStreamWriter;
 316             }
 317
 318             @Override
 319             public void leafNode(final NodeIdentifier name, final Object value) throws IOException {
 320                 if (name.getNodeType().equals(Draft02.RestConfModule.ERROR_INFO_QNAME)) {
 321                     String ns = Draft02.RestConfModule.ERROR_INFO_QNAME.getNamespace().toString();
 322                     try {
 323                         xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX,
 324                                 Draft02.RestConfModule.ERROR_INFO_QNAME.getLocalName(), ns);
 325                         xmlWriter.writeCharacters(value.toString());
 326                         xmlWriter.writeEndElement();
 327                     } catch (XMLStreamException e) {
 328                         throw new IOException("Error writing error-info", e);
 329                     }
 330                 } else {
 331                     super.leafNode(name, value);
 332                 }
 333             }
 334         };
 335
 336         final NormalizedNodeWriter nnWriter = NormalizedNodeWriter.forStreamWriter(streamWriter);
 337         try {
 338             if (isDataRoot) {
 339                 writeRootElement(xmlWriter, nnWriter, (ContainerNode) data);
 340             } else {
 341                 if (data instanceof MapEntryNode) {
 342                     // Restconf allows returning one list item. We need to wrap it
 343                     // in map node in order to serialize it properly
 344                     data = ImmutableNodes.mapNodeBuilder(data.getNodeType()).addChild((MapEntryNode) data).build();
 345                 }
 346                 nnWriter.write(data);
 347                 nnWriter.flush();
 348             }
 349         } catch (final IOException e) {
 350             LOG.warn("Error writing error response body.", e);
 351         }
 352
 353         return outStream.toString();
 354     }
 355
 356     private static void writeRootElement(final XMLStreamWriter xmlWriter, final NormalizedNodeWriter nnWriter,
 357                                          final ContainerNode data)
 358             throws IOException {
 359         try {
 360             final QName name = SchemaContext.NAME;
 361             xmlWriter.writeStartElement(name.getNamespace().toString(), name.getLocalName());
 362             for (final DataContainerChild<? extends PathArgument, ?> child : data.getValue()) {
 363                 nnWriter.write(child);
 364             }
 365             nnWriter.flush();
 366             xmlWriter.writeEndElement();
 367             xmlWriter.flush();
 368         } catch (final XMLStreamException e) {
 369             Throwables.propagate(e);
 370         }
 371     }
 372
 373     private static void writeDataRoot(final OutputStreamWriter outputWriter, final NormalizedNodeWriter nnWriter,
 374                                       final ContainerNode data) throws IOException {
 375         final Iterator<DataContainerChild<? extends PathArgument, ?>> iterator = data.getValue().iterator();
 376         while (iterator.hasNext()) {
 377             final DataContainerChild<? extends PathArgument, ?> child = iterator.next();
 378             nnWriter.write(child);
 379             nnWriter.flush();
 380         }
 381     }
 382 }