restconf/restconf-nb-bierman02/src/main/java/org/opendaylight/restconf/jersey/providers/JsonToPatchBodyReader.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
   9 package org.opendaylight.restconf.jersey.providers;
  10
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.collect.ImmutableList;
  13 import com.google.gson.stream.JsonReader;
  14 import com.google.gson.stream.JsonToken;
  15 import java.io.IOException;
  16 import java.io.InputStream;
  17 import java.io.InputStreamReader;
  18 import java.io.StringReader;
  19 import java.util.ArrayList;
  20 import java.util.List;
  21 import javax.annotation.Nonnull;
  22 import javax.ws.rs.Consumes;
  23 import javax.ws.rs.WebApplicationException;
  24 import javax.ws.rs.ext.Provider;
  25 import org.opendaylight.netconf.sal.restconf.impl.ControllerContext;
  26 import org.opendaylight.netconf.sal.restconf.impl.PatchContext;
  27 import org.opendaylight.netconf.sal.restconf.impl.PatchEditOperation;
  28 import org.opendaylight.netconf.sal.restconf.impl.PatchEntity;
  29 import org.opendaylight.netconf.sal.restconf.impl.RestconfDocumentedException;
  30 import org.opendaylight.netconf.sal.restconf.impl.RestconfError.ErrorTag;
  31 import org.opendaylight.netconf.sal.restconf.impl.RestconfError.ErrorType;
  32 import org.opendaylight.restconf.Rfc8040;
  33 import org.opendaylight.restconf.common.context.InstanceIdentifierContext;
  34 import org.opendaylight.restconf.utils.RestconfConstants;
  35 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  36 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
  37 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  38 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  39 import org.opendaylight.yangtools.yang.data.codec.gson.JsonParserStream;
  40 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNormalizedNodeStreamWriter;
  41 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeResult;
  42 import org.opendaylight.yangtools.yang.data.impl.schema.ResultAlreadySetException;
  43 import org.opendaylight.yangtools.yang.model.api.SchemaNode;
  44 import org.opendaylight.yangtools.yang.model.util.SchemaContextUtil;
  45 import org.slf4j.Logger;
  46 import org.slf4j.LoggerFactory;
  47
  48 @Provider
  49 @Consumes({Rfc8040.MediaTypes.PATCH + RestconfConstants.JSON})
  50 public class JsonToPatchBodyReader extends AbstractToPatchBodyReader {
  51     private static final Logger LOG = LoggerFactory.getLogger(JsonToPatchBodyReader.class);
  52
  53     private String patchId;
  54
  55     @SuppressWarnings("checkstyle:IllegalCatch")
  56     @Override
  57     protected PatchContext readBody(final InstanceIdentifierContext<?> path, final InputStream entityStream)
  58             throws IOException, WebApplicationException {
  59         try {
  60             return readFrom(path, entityStream);
  61         } catch (final Exception e) {
  62             throw propagateExceptionAs(e);
  63         }
  64     }
  65
  66     private PatchContext readFrom(final InstanceIdentifierContext<?> path, final InputStream entityStream)
  67             throws IOException {
  68         final JsonReader jsonReader = new JsonReader(new InputStreamReader(entityStream));
  69         final List<PatchEntity> resultList = read(jsonReader, path);
  70         jsonReader.close();
  71
  72         return new PatchContext(path, resultList, patchId);
  73     }
  74
  75     @SuppressWarnings("checkstyle:IllegalCatch")
  76     public PatchContext readFrom(final String uriPath, final InputStream entityStream) throws
  77             RestconfDocumentedException {
  78         try {
  79             return readFrom(ControllerContext.getInstance().toInstanceIdentifier(uriPath), entityStream);
  80         } catch (final Exception e) {
  81             propagateExceptionAs(e);
  82             return null; // no-op
  83         }
  84     }
  85
  86     private static RuntimeException propagateExceptionAs(final Exception exception) throws RestconfDocumentedException {
  87         if (exception instanceof RestconfDocumentedException) {
  88             throw (RestconfDocumentedException)exception;
  89         }
  90
  91         if (exception instanceof ResultAlreadySetException) {
  92             LOG.debug("Error parsing json input:", exception);
  93             throw new RestconfDocumentedException("Error parsing json input: Failed to create new parse result data. ");
  94         }
  95
  96         throw new RestconfDocumentedException("Error parsing json input: " + exception.getMessage(), ErrorType.PROTOCOL,
  97                 ErrorTag.MALFORMED_MESSAGE, exception);
  98     }
  99
 100     private List<PatchEntity> read(final JsonReader in, final InstanceIdentifierContext<?> path) throws IOException {
 101         final List<PatchEntity> resultCollection = new ArrayList<>();
 102         final StringModuleInstanceIdentifierCodec codec = new StringModuleInstanceIdentifierCodec(
 103                 path.getSchemaContext());
 104         final JsonToPatchBodyReader.PatchEdit edit = new JsonToPatchBodyReader.PatchEdit();
 105
 106         while (in.hasNext()) {
 107             switch (in.peek()) {
 108                 case STRING:
 109                 case NUMBER:
 110                     in.nextString();
 111                     break;
 112                 case BOOLEAN:
 113                     Boolean.toString(in.nextBoolean());
 114                     break;
 115                 case NULL:
 116                     in.nextNull();
 117                     break;
 118                 case BEGIN_ARRAY:
 119                     in.beginArray();
 120                     break;
 121                 case BEGIN_OBJECT:
 122                     in.beginObject();
 123                     break;
 124                 case END_DOCUMENT:
 125                     break;
 126                 case NAME:
 127                     parseByName(in.nextName(), edit, in, path, codec, resultCollection);
 128                     break;
 129                 case END_OBJECT:
 130                     in.endObject();
 131                     break;
 132                 case END_ARRAY:
 133                     in.endArray();
 134                     break;
 135
 136                 default:
 137                     break;
 138             }
 139         }
 140
 141         return ImmutableList.copyOf(resultCollection);
 142     }
 143
 144     /**
 145      * Switch value of parsed JsonToken.NAME and read edit definition or patch id.
 146      *
 147      * @param name value of token
 148      * @param edit PatchEdit instance
 149      * @param in JsonReader reader
 150      * @param path InstanceIdentifierContext context
 151      * @param codec Draft11StringModuleInstanceIdentifierCodec codec
 152      * @param resultCollection collection of parsed edits
 153      * @throws IOException if operation fails
 154      */
 155     private void parseByName(@Nonnull final String name, @Nonnull final PatchEdit edit,
 156                              @Nonnull final JsonReader in, @Nonnull final InstanceIdentifierContext<?> path,
 157                              @Nonnull final StringModuleInstanceIdentifierCodec codec,
 158                              @Nonnull final List<PatchEntity> resultCollection) throws IOException {
 159         switch (name) {
 160             case "edit":
 161                 if (in.peek() == JsonToken.BEGIN_ARRAY) {
 162                     in.beginArray();
 163
 164                     while (in.hasNext()) {
 165                         readEditDefinition(edit, in, path, codec);
 166                         resultCollection.add(prepareEditOperation(edit));
 167                         edit.clear();
 168                     }
 169
 170                     in.endArray();
 171                 } else {
 172                     readEditDefinition(edit, in, path, codec);
 173                     resultCollection.add(prepareEditOperation(edit));
 174                     edit.clear();
 175                 }
 176
 177                 break;
 178             case "patch-id":
 179                 this.patchId = in.nextString();
 180                 break;
 181             default:
 182                 break;
 183         }
 184     }
 185
 186     /**
 187      * Read one patch edit object from Json input.
 188      *
 189      * @param edit PatchEdit instance to be filled with read data
 190      * @param in JsonReader reader
 191      * @param path InstanceIdentifierContext path context
 192      * @param codec Draft11StringModuleInstanceIdentifierCodec codec
 193      * @throws IOException if operation fails
 194      */
 195     private void readEditDefinition(@Nonnull final PatchEdit edit, @Nonnull final JsonReader in,
 196                                     @Nonnull final InstanceIdentifierContext<?> path,
 197                                     @Nonnull final StringModuleInstanceIdentifierCodec codec) throws IOException {
 198         String deferredValue = null;
 199         in.beginObject();
 200
 201         while (in.hasNext()) {
 202             final String editDefinition = in.nextName();
 203             switch (editDefinition) {
 204                 case "edit-id":
 205                     edit.setId(in.nextString());
 206                     break;
 207                 case "operation":
 208                     edit.setOperation(PatchEditOperation.valueOf(in.nextString().toUpperCase()));
 209                     break;
 210                 case "target":
 211                     // target can be specified completely in request URI
 212                     final String target = in.nextString();
 213                     if (target.equals("/")) {
 214                         edit.setTarget(path.getInstanceIdentifier());
 215                         edit.setTargetSchemaNode(path.getSchemaContext());
 216                     } else {
 217                         edit.setTarget(codec.deserialize(codec.serialize(path.getInstanceIdentifier()).concat(target)));
 218                         edit.setTargetSchemaNode(SchemaContextUtil.findDataSchemaNode(path.getSchemaContext(),
 219                                 codec.getDataContextTree().getChild(edit.getTarget()).getDataSchemaNode().getPath()
 220                                         .getParent()));
 221                     }
 222
 223                     break;
 224                 case "value":
 225                     Preconditions.checkArgument(edit.getData() == null && deferredValue == null,
 226                             "Multiple value entries found");
 227
 228                     if (edit.getTargetSchemaNode() == null) {
 229                         final StringBuilder sb = new StringBuilder();
 230
 231                         // save data defined in value node for next (later) processing, because target needs to be read
 232                         // always first and there is no ordering in Json input
 233                         readValueNode(sb, in);
 234                         deferredValue = sb.toString();
 235                     } else {
 236                         // We have a target schema node, reuse this reader without buffering the value.
 237                         edit.setData(readEditData(in, edit.getTargetSchemaNode(), path));
 238                     }
 239                     break;
 240                 default:
 241                     // FIXME: this does not look right, as it can wreck our logic
 242                     break;
 243             }
 244         }
 245
 246         in.endObject();
 247
 248         if (deferredValue != null) {
 249             // read saved data to normalized node when target schema is already known
 250             edit.setData(readEditData(new JsonReader(new StringReader(deferredValue)), edit.getTargetSchemaNode(),
 251                 path));
 252         }
 253     }
 254
 255     /**
 256      * Parse data defined in value node and saves it to buffer.
 257      * @param sb Buffer to read value node
 258      * @param in JsonReader reader
 259      * @throws IOException if operation fails
 260      */
 261     private void readValueNode(@Nonnull final StringBuilder sb, @Nonnull final JsonReader in) throws IOException {
 262         in.beginObject();
 263
 264         sb.append("{\"").append(in.nextName()).append("\":");
 265
 266         switch (in.peek()) {
 267             case BEGIN_ARRAY:
 268                 in.beginArray();
 269                 sb.append('[');
 270
 271                 while (in.hasNext()) {
 272                     if (in.peek() == JsonToken.STRING) {
 273                         sb.append('"').append(in.nextString()).append('"');
 274                     } else {
 275                         readValueObject(sb, in);
 276                     }
 277                     if (in.peek() != JsonToken.END_ARRAY) {
 278                         sb.append(',');
 279                     }
 280                 }
 281
 282                 in.endArray();
 283                 sb.append(']');
 284                 break;
 285             default:
 286                 readValueObject(sb, in);
 287                 break;
 288         }
 289
 290         in.endObject();
 291         sb.append('}');
 292     }
 293
 294     /**
 295      * Parse one value object of data and saves it to buffer.
 296      * @param sb Buffer to read value object
 297      * @param in JsonReader reader
 298      * @throws IOException if operation fails
 299      */
 300     private void readValueObject(@Nonnull final StringBuilder sb, @Nonnull final JsonReader in) throws IOException {
 301         // read simple leaf value
 302         if (in.peek() == JsonToken.STRING) {
 303             sb.append('"').append(in.nextString()).append('"');
 304             return;
 305         }
 306
 307         in.beginObject();
 308         sb.append('{');
 309
 310         while (in.hasNext()) {
 311             sb.append('"').append(in.nextName()).append("\":");
 312
 313             switch (in.peek()) {
 314                 case STRING:
 315                     sb.append('"').append(in.nextString()).append('"');
 316                     break;
 317                 case BEGIN_ARRAY:
 318                     in.beginArray();
 319                     sb.append('[');
 320
 321                     while (in.hasNext()) {
 322                         if (in.peek() == JsonToken.STRING) {
 323                             sb.append('"').append(in.nextString()).append('"');
 324                         } else {
 325                             readValueObject(sb, in);
 326                         }
 327
 328                         if (in.peek() != JsonToken.END_ARRAY) {
 329                             sb.append(',');
 330                         }
 331                     }
 332
 333                     in.endArray();
 334                     sb.append(']');
 335                     break;
 336                 default:
 337                     readValueObject(sb, in);
 338             }
 339
 340             if (in.peek() != JsonToken.END_OBJECT) {
 341                 sb.append(',');
 342             }
 343         }
 344
 345         in.endObject();
 346         sb.append('}');
 347     }
 348
 349     /**
 350      * Read patch edit data defined in value node to NormalizedNode.
 351      * @param in reader JsonReader reader
 352      * @return NormalizedNode representing data
 353      */
 354     private static NormalizedNode<?, ?> readEditData(@Nonnull final JsonReader in,
 355             @Nonnull final SchemaNode targetSchemaNode, @Nonnull final InstanceIdentifierContext<?> path) {
 356         final NormalizedNodeResult resultHolder = new NormalizedNodeResult();
 357         final NormalizedNodeStreamWriter writer = ImmutableNormalizedNodeStreamWriter.from(resultHolder);
 358         JsonParserStream.create(writer, path.getSchemaContext(), targetSchemaNode).parse(in);
 359
 360         return resultHolder.getResult();
 361     }
 362
 363     /**
 364      * Prepare PatchEntity from PatchEdit instance when it satisfies conditions, otherwise throws exception.
 365      * @param edit Instance of PatchEdit
 366      * @return PatchEntity Patch entity
 367      */
 368     private static PatchEntity prepareEditOperation(@Nonnull final PatchEdit edit) {
 369         if (edit.getOperation() != null && edit.getTargetSchemaNode() != null
 370                 && checkDataPresence(edit.getOperation(), edit.getData() != null)) {
 371             if (!edit.getOperation().isWithValue()) {
 372                 return new PatchEntity(edit.getId(), edit.getOperation(), edit.getTarget());
 373             }
 374
 375             // for lists allow to manipulate with list items through their parent
 376             final YangInstanceIdentifier targetNode;
 377             if (edit.getTarget().getLastPathArgument() instanceof NodeIdentifierWithPredicates) {
 378                 targetNode = edit.getTarget().getParent();
 379             } else {
 380                 targetNode = edit.getTarget();
 381             }
 382
 383             return new PatchEntity(edit.getId(), edit.getOperation(), targetNode, edit.getData());
 384         }
 385
 386         throw new RestconfDocumentedException("Error parsing input", ErrorType.PROTOCOL, ErrorTag.MALFORMED_MESSAGE);
 387     }
 388
 389     /**
 390      * Check if data is present when operation requires it and not present when operation data is not allowed.
 391      * @param operation Name of operation
 392      * @param hasData Data in edit are present/not present
 393      * @return true if data is present when operation requires it or if there are no data when operation does not
 394      *     allow it, false otherwise
 395      */
 396     private static boolean checkDataPresence(@Nonnull final PatchEditOperation operation, final boolean hasData) {
 397         return operation.isWithValue() == hasData;
 398     }
 399
 400     /**
 401      * Helper class representing one patch edit.
 402      */
 403     private static final class PatchEdit {
 404         private String id;
 405         private PatchEditOperation operation;
 406         private YangInstanceIdentifier target;
 407         private SchemaNode targetSchemaNode;
 408         private NormalizedNode<?, ?> data;
 409
 410         String getId() {
 411             return id;
 412         }
 413
 414         void setId(final String id) {
 415             this.id = Preconditions.checkNotNull(id);
 416         }
 417
 418         PatchEditOperation getOperation() {
 419             return operation;
 420         }
 421
 422         void setOperation(final PatchEditOperation operation) {
 423             this.operation = Preconditions.checkNotNull(operation);
 424         }
 425
 426         YangInstanceIdentifier getTarget() {
 427             return target;
 428         }
 429
 430         void setTarget(final YangInstanceIdentifier target) {
 431             this.target = Preconditions.checkNotNull(target);
 432         }
 433
 434         SchemaNode getTargetSchemaNode() {
 435             return targetSchemaNode;
 436         }
 437
 438         void setTargetSchemaNode(final SchemaNode targetSchemaNode) {
 439             this.targetSchemaNode = Preconditions.checkNotNull(targetSchemaNode);
 440         }
 441
 442         NormalizedNode<?, ?> getData() {
 443             return data;
 444         }
 445
 446         void setData(final NormalizedNode<?, ?> data) {
 447             this.data = Preconditions.checkNotNull(data);
 448         }
 449
 450         void clear() {
 451             id = null;
 452             operation = null;
 453             target = null;
 454             targetSchemaNode = null;
 455             data = null;
 456         }
 457     }
 458 }