restconf/restconf-nb-rfc8040/src/main/java/org/opendaylight/restconf/nb/rfc8040/jersey/providers/patch/JsonPatchBodyReader.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.patch;
   9
  10 import static com.google.common.base.Preconditions.checkArgument;
  11 import static com.google.common.base.Verify.verify;
  12 import static java.util.Objects.requireNonNull;
  13
  14 import com.google.common.base.Throwables;
  15 import com.google.common.collect.ImmutableList;
  16 import com.google.gson.stream.JsonReader;
  17 import com.google.gson.stream.JsonToken;
  18 import java.io.IOException;
  19 import java.io.InputStream;
  20 import java.io.InputStreamReader;
  21 import java.io.StringReader;
  22 import java.nio.charset.StandardCharsets;
  23 import java.util.ArrayList;
  24 import java.util.List;
  25 import java.util.Locale;
  26 import java.util.Optional;
  27 import java.util.concurrent.atomic.AtomicReference;
  28 import javax.ws.rs.Consumes;
  29 import javax.ws.rs.WebApplicationException;
  30 import javax.ws.rs.ext.Provider;
  31 import org.eclipse.jdt.annotation.NonNull;
  32 import org.opendaylight.mdsal.dom.api.DOMMountPointService;
  33 import org.opendaylight.restconf.common.context.InstanceIdentifierContext;
  34 import org.opendaylight.restconf.common.errors.RestconfDocumentedException;
  35 import org.opendaylight.restconf.common.errors.RestconfError.ErrorTag;
  36 import org.opendaylight.restconf.common.patch.PatchContext;
  37 import org.opendaylight.restconf.common.patch.PatchEditOperation;
  38 import org.opendaylight.restconf.common.patch.PatchEntity;
  39 import org.opendaylight.restconf.nb.rfc8040.MediaTypes;
  40 import org.opendaylight.restconf.nb.rfc8040.codecs.StringModuleInstanceIdentifierCodec;
  41 import org.opendaylight.restconf.nb.rfc8040.handlers.SchemaContextHandler;
  42 import org.opendaylight.restconf.nb.rfc8040.utils.parser.ParserIdentifier;
  43 import org.opendaylight.yangtools.yang.common.ErrorType;
  44 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  45 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
  46 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  47 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  48 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactorySupplier;
  49 import org.opendaylight.yangtools.yang.data.codec.gson.JsonParserStream;
  50 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNormalizedNodeStreamWriter;
  51 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeResult;
  52 import org.opendaylight.yangtools.yang.data.impl.schema.ResultAlreadySetException;
  53 import org.opendaylight.yangtools.yang.model.api.SchemaNode;
  54 import org.opendaylight.yangtools.yang.model.api.meta.EffectiveStatement;
  55 import org.opendaylight.yangtools.yang.model.util.SchemaInferenceStack;
  56 import org.slf4j.Logger;
  57 import org.slf4j.LoggerFactory;
  58
  59 @Provider
  60 @Consumes(MediaTypes.APPLICATION_YANG_PATCH_JSON)
  61 public class JsonPatchBodyReader extends AbstractPatchBodyReader {
  62     private static final Logger LOG = LoggerFactory.getLogger(JsonPatchBodyReader.class);
  63
  64     public JsonPatchBodyReader(final SchemaContextHandler schemaContextHandler,
  65             final DOMMountPointService mountPointService) {
  66         super(schemaContextHandler, mountPointService);
  67     }
  68
  69     @SuppressWarnings("checkstyle:IllegalCatch")
  70     @Override
  71     protected PatchContext readBody(final InstanceIdentifierContext<?> path, final InputStream entityStream)
  72             throws WebApplicationException {
  73         try {
  74             return readFrom(path, entityStream);
  75         } catch (final Exception e) {
  76             throw propagateExceptionAs(e);
  77         }
  78     }
  79
  80     private PatchContext readFrom(final InstanceIdentifierContext<?> path, final InputStream entityStream)
  81             throws IOException {
  82         final JsonReader jsonReader = new JsonReader(new InputStreamReader(entityStream, StandardCharsets.UTF_8));
  83         AtomicReference<String> patchId = new AtomicReference<>();
  84         final List<PatchEntity> resultList = read(jsonReader, path, patchId);
  85         jsonReader.close();
  86
  87         return new PatchContext(path, resultList, patchId.get());
  88     }
  89
  90     @SuppressWarnings("checkstyle:IllegalCatch")
  91     public PatchContext readFrom(final String uriPath, final InputStream entityStream) throws
  92             RestconfDocumentedException {
  93         try {
  94             return readFrom(
  95                     ParserIdentifier.toInstanceIdentifier(uriPath, getSchemaContext(),
  96                             Optional.ofNullable(getMountPointService())), entityStream);
  97         } catch (final Exception e) {
  98             propagateExceptionAs(e);
  99             return null; // no-op
 100         }
 101     }
 102
 103     private static RuntimeException propagateExceptionAs(final Exception exception) throws RestconfDocumentedException {
 104         Throwables.throwIfInstanceOf(exception, RestconfDocumentedException.class);
 105         LOG.debug("Error parsing json input", exception);
 106
 107         if (exception instanceof ResultAlreadySetException) {
 108             throw new RestconfDocumentedException("Error parsing json input: Failed to create new parse result data. ");
 109         }
 110
 111         RestconfDocumentedException.throwIfYangError(exception);
 112         throw new RestconfDocumentedException("Error parsing json input: " + exception.getMessage(), ErrorType.PROTOCOL,
 113                 ErrorTag.MALFORMED_MESSAGE, exception);
 114     }
 115
 116     private List<PatchEntity> read(final JsonReader in, final InstanceIdentifierContext<?> path,
 117             final AtomicReference<String> patchId) throws IOException {
 118         final List<PatchEntity> resultCollection = new ArrayList<>();
 119         final StringModuleInstanceIdentifierCodec codec = new StringModuleInstanceIdentifierCodec(
 120                 path.getSchemaContext());
 121         final JsonPatchBodyReader.PatchEdit edit = new JsonPatchBodyReader.PatchEdit();
 122
 123         while (in.hasNext()) {
 124             switch (in.peek()) {
 125                 case STRING:
 126                 case NUMBER:
 127                     in.nextString();
 128                     break;
 129                 case BOOLEAN:
 130                     Boolean.toString(in.nextBoolean());
 131                     break;
 132                 case NULL:
 133                     in.nextNull();
 134                     break;
 135                 case BEGIN_ARRAY:
 136                     in.beginArray();
 137                     break;
 138                 case BEGIN_OBJECT:
 139                     in.beginObject();
 140                     break;
 141                 case END_DOCUMENT:
 142                     break;
 143                 case NAME:
 144                     parseByName(in.nextName(), edit, in, path, codec, resultCollection, patchId);
 145                     break;
 146                 case END_OBJECT:
 147                     in.endObject();
 148                     break;
 149                 case END_ARRAY:
 150                     in.endArray();
 151                     break;
 152
 153                 default:
 154                     break;
 155             }
 156         }
 157
 158         return ImmutableList.copyOf(resultCollection);
 159     }
 160
 161     /**
 162      * Switch value of parsed JsonToken.NAME and read edit definition or patch id.
 163      *
 164      * @param name value of token
 165      * @param edit PatchEdit instance
 166      * @param in JsonReader reader
 167      * @param path InstanceIdentifierContext context
 168      * @param codec Draft11StringModuleInstanceIdentifierCodec codec
 169      * @param resultCollection collection of parsed edits
 170      * @throws IOException if operation fails
 171      */
 172     private void parseByName(final @NonNull String name, final @NonNull PatchEdit edit,
 173                              final @NonNull JsonReader in, final @NonNull InstanceIdentifierContext<?> path,
 174                              final @NonNull StringModuleInstanceIdentifierCodec codec,
 175                              final @NonNull List<PatchEntity> resultCollection,
 176                              final @NonNull AtomicReference<String> patchId) throws IOException {
 177         switch (name) {
 178             case "edit":
 179                 if (in.peek() == JsonToken.BEGIN_ARRAY) {
 180                     in.beginArray();
 181
 182                     while (in.hasNext()) {
 183                         readEditDefinition(edit, in, path, codec);
 184                         resultCollection.add(prepareEditOperation(edit));
 185                         edit.clear();
 186                     }
 187
 188                     in.endArray();
 189                 } else {
 190                     readEditDefinition(edit, in, path, codec);
 191                     resultCollection.add(prepareEditOperation(edit));
 192                     edit.clear();
 193                 }
 194
 195                 break;
 196             case "patch-id":
 197                 patchId.set(in.nextString());
 198                 break;
 199             default:
 200                 break;
 201         }
 202     }
 203
 204     /**
 205      * Read one patch edit object from Json input.
 206      *
 207      * @param edit PatchEdit instance to be filled with read data
 208      * @param in JsonReader reader
 209      * @param path InstanceIdentifierContext path context
 210      * @param codec Draft11StringModuleInstanceIdentifierCodec codec
 211      * @throws IOException if operation fails
 212      */
 213     private void readEditDefinition(final @NonNull PatchEdit edit, final @NonNull JsonReader in,
 214                                     final @NonNull InstanceIdentifierContext<?> path,
 215                                     final @NonNull StringModuleInstanceIdentifierCodec codec) throws IOException {
 216         String deferredValue = null;
 217         in.beginObject();
 218
 219         while (in.hasNext()) {
 220             final String editDefinition = in.nextName();
 221             switch (editDefinition) {
 222                 case "edit-id":
 223                     edit.setId(in.nextString());
 224                     break;
 225                 case "operation":
 226                     edit.setOperation(PatchEditOperation.valueOf(in.nextString().toUpperCase(Locale.ROOT)));
 227                     break;
 228                 case "target":
 229                     // target can be specified completely in request URI
 230                     final String target = in.nextString();
 231                     if (target.equals("/")) {
 232                         edit.setTarget(path.getInstanceIdentifier());
 233                         edit.setTargetSchemaNode(path.getSchemaContext());
 234                     } else {
 235                         edit.setTarget(codec.deserialize(codec.serialize(path.getInstanceIdentifier()).concat(target)));
 236
 237                         final EffectiveStatement<?, ?> parentStmt = SchemaInferenceStack.ofInstantiatedPath(
 238                             path.getSchemaContext(),
 239                             codec.getDataContextTree().findChild(edit.getTarget()).orElseThrow().getDataSchemaNode()
 240                                 .getPath().getParent())
 241                             .currentStatement();
 242                         verify(parentStmt instanceof SchemaNode, "Unexpected parent %s", parentStmt);
 243                         edit.setTargetSchemaNode((SchemaNode) parentStmt);
 244                     }
 245
 246                     break;
 247                 case "value":
 248                     checkArgument(edit.getData() == null && deferredValue == null, "Multiple value entries found");
 249
 250                     if (edit.getTargetSchemaNode() == null) {
 251                         final StringBuilder sb = new StringBuilder();
 252
 253                         // save data defined in value node for next (later) processing, because target needs to be read
 254                         // always first and there is no ordering in Json input
 255                         readValueNode(sb, in);
 256                         deferredValue = sb.toString();
 257                     } else {
 258                         // We have a target schema node, reuse this reader without buffering the value.
 259                         edit.setData(readEditData(in, edit.getTargetSchemaNode(), path));
 260                     }
 261                     break;
 262                 default:
 263                     // FIXME: this does not look right, as it can wreck our logic
 264                     break;
 265             }
 266         }
 267
 268         in.endObject();
 269
 270         if (deferredValue != null) {
 271             // read saved data to normalized node when target schema is already known
 272             edit.setData(readEditData(new JsonReader(new StringReader(deferredValue)), edit.getTargetSchemaNode(),
 273                 path));
 274         }
 275     }
 276
 277     /**
 278      * Parse data defined in value node and saves it to buffer.
 279      * @param sb Buffer to read value node
 280      * @param in JsonReader reader
 281      * @throws IOException if operation fails
 282      */
 283     private void readValueNode(final @NonNull StringBuilder sb, final @NonNull JsonReader in) throws IOException {
 284         in.beginObject();
 285
 286         sb.append("{\"").append(in.nextName()).append("\":");
 287
 288         switch (in.peek()) {
 289             case BEGIN_ARRAY:
 290                 in.beginArray();
 291                 sb.append('[');
 292
 293                 while (in.hasNext()) {
 294                     if (in.peek() == JsonToken.STRING) {
 295                         sb.append('"').append(in.nextString()).append('"');
 296                     } else {
 297                         readValueObject(sb, in);
 298                     }
 299                     if (in.peek() != JsonToken.END_ARRAY) {
 300                         sb.append(',');
 301                     }
 302                 }
 303
 304                 in.endArray();
 305                 sb.append(']');
 306                 break;
 307             default:
 308                 readValueObject(sb, in);
 309                 break;
 310         }
 311
 312         in.endObject();
 313         sb.append('}');
 314     }
 315
 316     /**
 317      * Parse one value object of data and saves it to buffer.
 318      * @param sb Buffer to read value object
 319      * @param in JsonReader reader
 320      * @throws IOException if operation fails
 321      */
 322     private void readValueObject(final @NonNull StringBuilder sb, final @NonNull JsonReader in) throws IOException {
 323         // read simple leaf value
 324         if (in.peek() == JsonToken.STRING) {
 325             sb.append('"').append(in.nextString()).append('"');
 326             return;
 327         }
 328
 329         in.beginObject();
 330         sb.append('{');
 331
 332         while (in.hasNext()) {
 333             sb.append('"').append(in.nextName()).append("\":");
 334
 335             switch (in.peek()) {
 336                 case STRING:
 337                     sb.append('"').append(in.nextString()).append('"');
 338                     break;
 339                 case BEGIN_ARRAY:
 340                     in.beginArray();
 341                     sb.append('[');
 342
 343                     while (in.hasNext()) {
 344                         if (in.peek() == JsonToken.STRING) {
 345                             sb.append('"').append(in.nextString()).append('"');
 346                         } else {
 347                             readValueObject(sb, in);
 348                         }
 349
 350                         if (in.peek() != JsonToken.END_ARRAY) {
 351                             sb.append(',');
 352                         }
 353                     }
 354
 355                     in.endArray();
 356                     sb.append(']');
 357                     break;
 358                 default:
 359                     readValueObject(sb, in);
 360             }
 361
 362             if (in.peek() != JsonToken.END_OBJECT) {
 363                 sb.append(',');
 364             }
 365         }
 366
 367         in.endObject();
 368         sb.append('}');
 369     }
 370
 371     /**
 372      * Read patch edit data defined in value node to NormalizedNode.
 373      * @param in reader JsonReader reader
 374      * @return NormalizedNode representing data
 375      */
 376     private static NormalizedNode readEditData(final @NonNull JsonReader in,
 377              final @NonNull SchemaNode targetSchemaNode, final @NonNull InstanceIdentifierContext<?> path) {
 378         final NormalizedNodeResult resultHolder = new NormalizedNodeResult();
 379         final NormalizedNodeStreamWriter writer = ImmutableNormalizedNodeStreamWriter.from(resultHolder);
 380         JsonParserStream.create(writer, JSONCodecFactorySupplier.RFC7951.getShared(path.getSchemaContext()),
 381             SchemaInferenceStack.ofInstantiatedPath(path.getSchemaContext(), targetSchemaNode.getPath()).toInference())
 382             .parse(in);
 383
 384         return resultHolder.getResult();
 385     }
 386
 387     /**
 388      * Prepare PatchEntity from PatchEdit instance when it satisfies conditions, otherwise throws exception.
 389      * @param edit Instance of PatchEdit
 390      * @return PatchEntity Patch entity
 391      */
 392     private static PatchEntity prepareEditOperation(final @NonNull PatchEdit edit) {
 393         if (edit.getOperation() != null && edit.getTargetSchemaNode() != null
 394                 && checkDataPresence(edit.getOperation(), edit.getData() != null)) {
 395             if (!edit.getOperation().isWithValue()) {
 396                 return new PatchEntity(edit.getId(), edit.getOperation(), edit.getTarget());
 397             }
 398
 399             // for lists allow to manipulate with list items through their parent
 400             final YangInstanceIdentifier targetNode;
 401             if (edit.getTarget().getLastPathArgument() instanceof NodeIdentifierWithPredicates) {
 402                 targetNode = edit.getTarget().getParent();
 403             } else {
 404                 targetNode = edit.getTarget();
 405             }
 406
 407             return new PatchEntity(edit.getId(), edit.getOperation(), targetNode, edit.getData());
 408         }
 409
 410         throw new RestconfDocumentedException("Error parsing input", ErrorType.PROTOCOL, ErrorTag.MALFORMED_MESSAGE);
 411     }
 412
 413     /**
 414      * Check if data is present when operation requires it and not present when operation data is not allowed.
 415      * @param operation Name of operation
 416      * @param hasData Data in edit are present/not present
 417      * @return true if data is present when operation requires it or if there are no data when operation does not
 418      *     allow it, false otherwise
 419      */
 420     private static boolean checkDataPresence(final @NonNull PatchEditOperation operation, final boolean hasData) {
 421         return operation.isWithValue() == hasData;
 422     }
 423
 424     /**
 425      * Helper class representing one patch edit.
 426      */
 427     private static final class PatchEdit {
 428         private String id;
 429         private PatchEditOperation operation;
 430         private YangInstanceIdentifier target;
 431         private SchemaNode targetSchemaNode;
 432         private NormalizedNode data;
 433
 434         String getId() {
 435             return id;
 436         }
 437
 438         void setId(final String id) {
 439             this.id = requireNonNull(id);
 440         }
 441
 442         PatchEditOperation getOperation() {
 443             return operation;
 444         }
 445
 446         void setOperation(final PatchEditOperation operation) {
 447             this.operation = requireNonNull(operation);
 448         }
 449
 450         YangInstanceIdentifier getTarget() {
 451             return target;
 452         }
 453
 454         void setTarget(final YangInstanceIdentifier target) {
 455             this.target = requireNonNull(target);
 456         }
 457
 458         SchemaNode getTargetSchemaNode() {
 459             return targetSchemaNode;
 460         }
 461
 462         void setTargetSchemaNode(final SchemaNode targetSchemaNode) {
 463             this.targetSchemaNode = requireNonNull(targetSchemaNode);
 464         }
 465
 466         NormalizedNode getData() {
 467             return data;
 468         }
 469
 470         void setData(final NormalizedNode data) {
 471             this.data = requireNonNull(data);
 472         }
 473
 474         void clear() {
 475             id = null;
 476             operation = null;
 477             target = null;
 478             targetSchemaNode = null;
 479             data = null;
 480         }
 481     }
 482 }