opendaylight/restconf/sal-rest-connector/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.Charsets;
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.base.Throwables;
  14 import com.google.common.collect.Iterables;
  15 import com.google.gson.stream.JsonWriter;
  16 import java.io.ByteArrayOutputStream;
  17 import java.io.IOException;
  18 import java.io.OutputStreamWriter;
  19 import java.net.URI;
  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.InstanceIdentifierContext;
  36 import org.opendaylight.netconf.sal.restconf.impl.NormalizedNodeContext;
  37 import org.opendaylight.netconf.sal.restconf.impl.RestconfDocumentedException;
  38 import org.opendaylight.netconf.sal.restconf.impl.RestconfError;
  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.impl.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 final static 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(errListSchemaNode instanceof ListSchemaNode, "Found Error SchemaNode isn't ListSchemaNode");
 137         final CollectionNodeBuilder<MapEntryNode, MapNode> listErorsBuilder = Builders
 138                 .mapBuilder((ListSchemaNode) errListSchemaNode);
 139
 140
 141         for (final RestconfError error : errors) {
 142             listErorsBuilder.withChild(toErrorEntryNode(error, errListSchemaNode));
 143         }
 144         errContBuild.withChild(listErorsBuilder.build());
 145
 146         final NormalizedNodeContext errContext =  new NormalizedNodeContext(new InstanceIdentifierContext<>(null,
 147                 (DataSchemaNode) errorsSchemaNode, null, context.getGlobalSchema()), errContBuild.build());
 148
 149         Object responseBody;
 150         if (mediaType.getSubtype().endsWith("json")) {
 151             responseBody = toJsonResponseBody(errContext, errorsSchemaNode);
 152         } else {
 153             responseBody = toXMLResponseBody(errContext, errorsSchemaNode);
 154         }
 155
 156         return Response.status(status).type(mediaType).entity(responseBody).build();
 157     }
 158
 159     private static MapEntryNode toErrorEntryNode(final RestconfError error, final DataSchemaNode errListSchemaNode) {
 160         Preconditions.checkArgument(errListSchemaNode instanceof ListSchemaNode,
 161                 "errListSchemaNode has to be of type ListSchemaNode");
 162         final ListSchemaNode listStreamSchemaNode = (ListSchemaNode) errListSchemaNode;
 163         final DataContainerNodeAttrBuilder<NodeIdentifierWithPredicates, MapEntryNode> errNodeValues = Builders
 164                 .mapEntryBuilder(listStreamSchemaNode);
 165
 166         List<DataSchemaNode> lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 167                 (listStreamSchemaNode), "error-type");
 168         final DataSchemaNode errTypSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 169         Preconditions.checkState(errTypSchemaNode instanceof LeafSchemaNode);
 170         errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errTypSchemaNode)
 171                 .withValue(error.getErrorType().getErrorTypeTag()).build());
 172
 173         lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 174                 (listStreamSchemaNode), "error-tag");
 175         final DataSchemaNode errTagSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 176         Preconditions.checkState(errTagSchemaNode instanceof LeafSchemaNode);
 177         errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errTagSchemaNode)
 178                 .withValue(error.getErrorTag().getTagValue()).build());
 179
 180         if (error.getErrorAppTag() != null) {
 181             lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 182                     (listStreamSchemaNode), "error-app-tag");
 183             final DataSchemaNode errAppTagSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 184             Preconditions.checkState(errAppTagSchemaNode instanceof LeafSchemaNode);
 185             errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errAppTagSchemaNode)
 186                     .withValue(error.getErrorAppTag()).build());
 187         }
 188
 189         lsChildDataSchemaNode = ControllerContext.findInstanceDataChildrenByName(
 190                 (listStreamSchemaNode), "error-message");
 191         final DataSchemaNode errMsgSchemaNode = Iterables.getFirst(lsChildDataSchemaNode, null);
 192         Preconditions.checkState(errMsgSchemaNode instanceof LeafSchemaNode);
 193         errNodeValues.withChild(Builders.leafBuilder((LeafSchemaNode) errMsgSchemaNode)
 194                 .withValue(error.getErrorMessage()).build());
 195
 196         if(error.getErrorInfo() != null) {
 197             // Oddly, error-info is defined as an empty container in the restconf yang. Apparently the
 198             // intention is for implementors to define their own data content so we'll just treat it as a leaf
 199             // with string data.
 200             errNodeValues.withChild(ImmutableNodes.leafNode(Draft02.RestConfModule.ERROR_INFO_QNAME,
 201                     error.getErrorInfo()));
 202         }
 203
 204         // TODO : find how could we add possible "error-path"
 205
 206         return errNodeValues.build();
 207     }
 208
 209     private static Object toJsonResponseBody(final NormalizedNodeContext errorsNode, final DataNodeContainer errorsSchemaNode) {
 210         final ByteArrayOutputStream outStream = new ByteArrayOutputStream();
 211         NormalizedNode<?, ?> data = errorsNode.getData();
 212         final InstanceIdentifierContext<?> context = errorsNode.getInstanceIdentifierContext();
 213         final DataSchemaNode schema = (DataSchemaNode) context.getSchemaNode();
 214
 215         SchemaPath path = context.getSchemaNode().getPath();
 216         final OutputStreamWriter outputWriter = new OutputStreamWriter(outStream, Charsets.UTF_8);
 217         if (data == null) {
 218             throw new RestconfDocumentedException(Response.Status.NOT_FOUND);
 219         }
 220
 221         boolean isDataRoot = false;
 222         URI initialNs = null;
 223         if (SchemaPath.ROOT.equals(path)) {
 224             isDataRoot = true;
 225         } else {
 226             path = path.getParent();
 227             // FIXME: Add proper handling of reading root.
 228         }
 229         if (!schema.isAugmenting() && !(schema instanceof SchemaContext)) {
 230             initialNs = schema.getQName().getNamespace();
 231         }
 232
 233         final JsonWriter jsonWriter = JsonWriterFactory.createJsonWriter(outputWriter);
 234         final NormalizedNodeStreamWriter jsonStreamWriter = JSONNormalizedNodeStreamWriter.createExclusiveWriter(
 235                 JSONCodecFactory.create(context.getSchemaContext()), path, initialNs, jsonWriter);
 236
 237         // We create a delegating writer to special-case error-info as error-info is defined as an empty
 238         // container in the restconf yang schema but we create a leaf node so we can output it. The delegate
 239         // stream writer validates the node type against the schema and thus will expect a LeafSchemaNode but
 240         // the schema has a ContainerSchemaNode so, to avoid an error, we override the leafNode behavior
 241         // for error-info.
 242         final NormalizedNodeStreamWriter streamWriter = new ForwardingNormalizedNodeStreamWriter() {
 243             @Override
 244             protected NormalizedNodeStreamWriter delegate() {
 245                 return jsonStreamWriter;
 246             }
 247
 248             @Override
 249             public void leafNode(final NodeIdentifier name, final Object value) throws IOException {
 250                 if(name.getNodeType().equals(Draft02.RestConfModule.ERROR_INFO_QNAME)) {
 251                     jsonWriter.name(Draft02.RestConfModule.ERROR_INFO_QNAME.getLocalName());
 252                     jsonWriter.value(value.toString());
 253                 } else {
 254                     super.leafNode(name, value);
 255                 }
 256             }
 257         };
 258
 259         final NormalizedNodeWriter nnWriter = NormalizedNodeWriter.forStreamWriter(streamWriter);
 260         try {
 261             if (isDataRoot) {
 262                 writeDataRoot(outputWriter,nnWriter,(ContainerNode) data);
 263             } else {
 264                 if (data instanceof MapEntryNode) {
 265                     data = ImmutableNodes.mapNodeBuilder(data.getNodeType()).withChild(((MapEntryNode) data)).build();
 266                 }
 267                 nnWriter.write(data);
 268             }
 269             nnWriter.flush();
 270             outputWriter.flush();
 271         } catch (final IOException e) {
 272             LOG.warn("Error writing error response body", e);
 273         }
 274
 275         return outStream.toString();
 276
 277     }
 278
 279     private static Object toXMLResponseBody(final NormalizedNodeContext errorsNode, final DataNodeContainer errorsSchemaNode) {
 280         final InstanceIdentifierContext<?> pathContext = errorsNode.getInstanceIdentifierContext();
 281         final ByteArrayOutputStream outStream = new ByteArrayOutputStream();
 282
 283         final XMLStreamWriter xmlWriter;
 284         try {
 285             xmlWriter = XML_FACTORY.createXMLStreamWriter(outStream, "UTF-8");
 286         } catch (final XMLStreamException e) {
 287             throw new IllegalStateException(e);
 288         } catch (final FactoryConfigurationError e) {
 289             throw new IllegalStateException(e);
 290         }
 291         NormalizedNode<?, ?> data = errorsNode.getData();
 292         SchemaPath schemaPath = pathContext.getSchemaNode().getPath();
 293
 294         boolean isDataRoot = false;
 295         if (SchemaPath.ROOT.equals(schemaPath)) {
 296             isDataRoot = true;
 297         } else {
 298             schemaPath = schemaPath.getParent();
 299         }
 300
 301         final NormalizedNodeStreamWriter xmlStreamWriter = XMLStreamNormalizedNodeStreamWriter.create(xmlWriter,
 302                 pathContext.getSchemaContext(), schemaPath);
 303
 304         // We create a delegating writer to special-case error-info as error-info is defined as an empty
 305         // container in the restconf yang schema but we create a leaf node so we can output it. The delegate
 306         // stream writer validates the node type against the schema and thus will expect a LeafSchemaNode but
 307         // the schema has a ContainerSchemaNode so, to avoid an error, we override the leafNode behavior
 308         // for error-info.
 309         final NormalizedNodeStreamWriter streamWriter = new ForwardingNormalizedNodeStreamWriter() {
 310             @Override
 311             protected NormalizedNodeStreamWriter delegate() {
 312                 return xmlStreamWriter;
 313             }
 314
 315             @Override
 316             public void leafNode(final NodeIdentifier name, final Object value) throws IOException {
 317                 if(name.getNodeType().equals(Draft02.RestConfModule.ERROR_INFO_QNAME)) {
 318                     String ns = Draft02.RestConfModule.ERROR_INFO_QNAME.getNamespace().toString();
 319                     try {
 320                         xmlWriter.writeStartElement(XMLConstants.DEFAULT_NS_PREFIX,
 321                                 Draft02.RestConfModule.ERROR_INFO_QNAME.getLocalName(), ns);
 322                         xmlWriter.writeCharacters(value.toString());
 323                         xmlWriter.writeEndElement();
 324                     } catch (XMLStreamException e) {
 325                         throw new IOException("Error writing error-info", e);
 326                     }
 327                 } else {
 328                     super.leafNode(name, value);
 329                 }
 330             }
 331         };
 332
 333         final NormalizedNodeWriter nnWriter = NormalizedNodeWriter.forStreamWriter(streamWriter);
 334         try {
 335             if (isDataRoot) {
 336                 writeRootElement(xmlWriter, nnWriter, (ContainerNode) data);
 337             } else {
 338                 if (data instanceof MapEntryNode) {
 339                     // Restconf allows returning one list item. We need to wrap it
 340                     // in map node in order to serialize it properly
 341                     data = ImmutableNodes.mapNodeBuilder(data.getNodeType()).addChild((MapEntryNode) data).build();
 342                 }
 343                 nnWriter.write(data);
 344                 nnWriter.flush();
 345             }
 346         }
 347         catch (final IOException e) {
 348             LOG.warn("Error writing error response body.", e);
 349         }
 350
 351         return outStream.toString();
 352     }
 353
 354     private static void writeRootElement(final XMLStreamWriter xmlWriter, final NormalizedNodeWriter nnWriter, final ContainerNode data)
 355             throws IOException {
 356         try {
 357             final QName name = SchemaContext.NAME;
 358             xmlWriter.writeStartElement(name.getNamespace().toString(), name.getLocalName());
 359             for (final DataContainerChild<? extends PathArgument, ?> child : data.getValue()) {
 360                 nnWriter.write(child);
 361             }
 362             nnWriter.flush();
 363             xmlWriter.writeEndElement();
 364             xmlWriter.flush();
 365         } catch (final XMLStreamException e) {
 366             Throwables.propagate(e);
 367         }
 368     }
 369
 370     private static void writeDataRoot(final OutputStreamWriter outputWriter, final NormalizedNodeWriter nnWriter, final ContainerNode data) throws IOException {
 371         final Iterator<DataContainerChild<? extends PathArgument, ?>> iterator = data.getValue().iterator();
 372         while (iterator.hasNext()) {
 373             final DataContainerChild<? extends PathArgument, ?> child = iterator.next();
 374             nnWriter.write(child);
 375             nnWriter.flush();
 376         }
 377     }
 378 }