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.patch.PatchContext;
  36 import org.opendaylight.restconf.common.patch.PatchEditOperation;
  37 import org.opendaylight.restconf.common.patch.PatchEntity;
  38 import org.opendaylight.restconf.nb.rfc8040.MediaTypes;
  39 import org.opendaylight.restconf.nb.rfc8040.handlers.SchemaContextHandler;
  40 import org.opendaylight.restconf.nb.rfc8040.utils.parser.ParserIdentifier;
  41 import org.opendaylight.yangtools.yang.common.ErrorTag;
  42 import org.opendaylight.yangtools.yang.common.ErrorType;
  43 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  44 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
  45 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  46 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  47 import org.opendaylight.yangtools.yang.data.codec.gson.JSONCodecFactorySupplier;
  48 import org.opendaylight.yangtools.yang.data.codec.gson.JsonParserStream;
  49 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNormalizedNodeStreamWriter;
  50 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeResult;
  51 import org.opendaylight.yangtools.yang.data.impl.schema.ResultAlreadySetException;
  52 import org.opendaylight.yangtools.yang.data.util.DataSchemaContextTree;
  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 DataSchemaContextTree schemaTree = DataSchemaContextTree.from(path.getSchemaContext());
 119         final List<PatchEntity> resultCollection = new ArrayList<>();
 120         final JsonPatchBodyReader.PatchEdit edit = new JsonPatchBodyReader.PatchEdit();
 121
 122         while (in.hasNext()) {
 123             switch (in.peek()) {
 124                 case STRING:
 125                 case NUMBER:
 126                     in.nextString();
 127                     break;
 128                 case BOOLEAN:
 129                     Boolean.toString(in.nextBoolean());
 130                     break;
 131                 case NULL:
 132                     in.nextNull();
 133                     break;
 134                 case BEGIN_ARRAY:
 135                     in.beginArray();
 136                     break;
 137                 case BEGIN_OBJECT:
 138                     in.beginObject();
 139                     break;
 140                 case END_DOCUMENT:
 141                     break;
 142                 case NAME:
 143                     parseByName(in.nextName(), edit, in, path, schemaTree, resultCollection, patchId);
 144                     break;
 145                 case END_OBJECT:
 146                     in.endObject();
 147                     break;
 148                 case END_ARRAY:
 149                     in.endArray();
 150                     break;
 151
 152                 default:
 153                     break;
 154             }
 155         }
 156
 157         return ImmutableList.copyOf(resultCollection);
 158     }
 159
 160     /**
 161      * Switch value of parsed JsonToken.NAME and read edit definition or patch id.
 162      *
 163      * @param name value of token
 164      * @param edit PatchEdit instance
 165      * @param in JsonReader reader
 166      * @param path InstanceIdentifierContext context
 167      * @param codec Draft11StringModuleInstanceIdentifierCodec codec
 168      * @param resultCollection collection of parsed edits
 169      * @throws IOException if operation fails
 170      */
 171     private void parseByName(final @NonNull String name, final @NonNull PatchEdit edit,
 172                              final @NonNull JsonReader in, final @NonNull InstanceIdentifierContext<?> path,
 173                              final @NonNull DataSchemaContextTree schemaTree,
 174                              final @NonNull List<PatchEntity> resultCollection,
 175                              final @NonNull AtomicReference<String> patchId) throws IOException {
 176         switch (name) {
 177             case "edit":
 178                 if (in.peek() == JsonToken.BEGIN_ARRAY) {
 179                     in.beginArray();
 180
 181                     while (in.hasNext()) {
 182                         readEditDefinition(edit, in, path, schemaTree);
 183                         resultCollection.add(prepareEditOperation(edit));
 184                         edit.clear();
 185                     }
 186
 187                     in.endArray();
 188                 } else {
 189                     readEditDefinition(edit, in, path, schemaTree);
 190                     resultCollection.add(prepareEditOperation(edit));
 191                     edit.clear();
 192                 }
 193
 194                 break;
 195             case "patch-id":
 196                 patchId.set(in.nextString());
 197                 break;
 198             default:
 199                 break;
 200         }
 201     }
 202
 203     /**
 204      * Read one patch edit object from Json input.
 205      *
 206      * @param edit PatchEdit instance to be filled with read data
 207      * @param in JsonReader reader
 208      * @param path InstanceIdentifierContext path context
 209      * @param codec Draft11StringModuleInstanceIdentifierCodec codec
 210      * @throws IOException if operation fails
 211      */
 212     private void readEditDefinition(final @NonNull PatchEdit edit, final @NonNull JsonReader in,
 213                                     final @NonNull InstanceIdentifierContext<?> path,
 214                                     final @NonNull DataSchemaContextTree schemaTree) throws IOException {
 215         String deferredValue = null;
 216         in.beginObject();
 217
 218         while (in.hasNext()) {
 219             final String editDefinition = in.nextName();
 220             switch (editDefinition) {
 221                 case "edit-id":
 222                     edit.setId(in.nextString());
 223                     break;
 224                 case "operation":
 225                     edit.setOperation(PatchEditOperation.valueOf(in.nextString().toUpperCase(Locale.ROOT)));
 226                     break;
 227                 case "target":
 228                     // target can be specified completely in request URI
 229                     final String target = in.nextString();
 230                     if (target.equals("/")) {
 231                         edit.setTarget(path.getInstanceIdentifier());
 232                         edit.setTargetSchemaNode(path.getSchemaContext());
 233                     } else {
 234                         edit.setTarget(ParserIdentifier.parserPatchTarget(path, target));
 235
 236                         final EffectiveStatement<?, ?> parentStmt = SchemaInferenceStack.ofInstantiatedPath(
 237                             path.getSchemaContext(),
 238                             schemaTree.findChild(edit.getTarget()).orElseThrow().getDataSchemaNode()
 239                                 .getPath().getParent())
 240                             .currentStatement();
 241                         verify(parentStmt instanceof SchemaNode, "Unexpected parent %s", parentStmt);
 242                         edit.setTargetSchemaNode((SchemaNode) parentStmt);
 243                     }
 244
 245                     break;
 246                 case "value":
 247                     checkArgument(edit.getData() == null && deferredValue == null, "Multiple value entries found");
 248
 249                     if (edit.getTargetSchemaNode() == null) {
 250                         // save data defined in value node for next (later) processing, because target needs to be read
 251                         // always first and there is no ordering in Json input
 252                         deferredValue = readValueNode(in);
 253                     } else {
 254                         // We have a target schema node, reuse this reader without buffering the value.
 255                         edit.setData(readEditData(in, edit.getTargetSchemaNode(), path));
 256                     }
 257                     break;
 258                 default:
 259                     // FIXME: this does not look right, as it can wreck our logic
 260                     break;
 261             }
 262         }
 263
 264         in.endObject();
 265
 266         if (deferredValue != null) {
 267             // read saved data to normalized node when target schema is already known
 268             edit.setData(readEditData(new JsonReader(new StringReader(deferredValue)), edit.getTargetSchemaNode(),
 269                 path));
 270         }
 271     }
 272
 273     /**
 274      * Parse data defined in value node and saves it to buffer.
 275      * @param sb Buffer to read value node
 276      * @param in JsonReader reader
 277      * @throws IOException if operation fails
 278      */
 279     private String readValueNode(final @NonNull JsonReader in) throws IOException {
 280         in.beginObject();
 281         final StringBuilder sb = new StringBuilder().append("{\"").append(in.nextName()).append("\":");
 282
 283         switch (in.peek()) {
 284             case BEGIN_ARRAY:
 285                 in.beginArray();
 286                 sb.append('[');
 287
 288                 while (in.hasNext()) {
 289                     if (in.peek() == JsonToken.STRING) {
 290                         sb.append('"').append(in.nextString()).append('"');
 291                     } else {
 292                         readValueObject(sb, in);
 293                     }
 294                     if (in.peek() != JsonToken.END_ARRAY) {
 295                         sb.append(',');
 296                     }
 297                 }
 298
 299                 in.endArray();
 300                 sb.append(']');
 301                 break;
 302             default:
 303                 readValueObject(sb, in);
 304                 break;
 305         }
 306
 307         in.endObject();
 308         return sb.append('}').toString();
 309     }
 310
 311     /**
 312      * Parse one value object of data and saves it to buffer.
 313      * @param sb Buffer to read value object
 314      * @param in JsonReader reader
 315      * @throws IOException if operation fails
 316      */
 317     private void readValueObject(final @NonNull StringBuilder sb, final @NonNull JsonReader in) throws IOException {
 318         // read simple leaf value
 319         if (in.peek() == JsonToken.STRING) {
 320             sb.append('"').append(in.nextString()).append('"');
 321             return;
 322         }
 323
 324         in.beginObject();
 325         sb.append('{');
 326
 327         while (in.hasNext()) {
 328             sb.append('"').append(in.nextName()).append("\":");
 329
 330             switch (in.peek()) {
 331                 case STRING:
 332                     sb.append('"').append(in.nextString()).append('"');
 333                     break;
 334                 case BEGIN_ARRAY:
 335                     in.beginArray();
 336                     sb.append('[');
 337
 338                     while (in.hasNext()) {
 339                         if (in.peek() == JsonToken.STRING) {
 340                             sb.append('"').append(in.nextString()).append('"');
 341                         } else {
 342                             readValueObject(sb, in);
 343                         }
 344
 345                         if (in.peek() != JsonToken.END_ARRAY) {
 346                             sb.append(',');
 347                         }
 348                     }
 349
 350                     in.endArray();
 351                     sb.append(']');
 352                     break;
 353                 default:
 354                     readValueObject(sb, in);
 355             }
 356
 357             if (in.peek() != JsonToken.END_OBJECT) {
 358                 sb.append(',');
 359             }
 360         }
 361
 362         in.endObject();
 363         sb.append('}');
 364     }
 365
 366     /**
 367      * Read patch edit data defined in value node to NormalizedNode.
 368      * @param in reader JsonReader reader
 369      * @return NormalizedNode representing data
 370      */
 371     private static NormalizedNode readEditData(final @NonNull JsonReader in,
 372              final @NonNull SchemaNode targetSchemaNode, final @NonNull InstanceIdentifierContext<?> path) {
 373         final NormalizedNodeResult resultHolder = new NormalizedNodeResult();
 374         final NormalizedNodeStreamWriter writer = ImmutableNormalizedNodeStreamWriter.from(resultHolder);
 375         JsonParserStream.create(writer, JSONCodecFactorySupplier.RFC7951.getShared(path.getSchemaContext()),
 376             SchemaInferenceStack.ofInstantiatedPath(path.getSchemaContext(), targetSchemaNode.getPath()).toInference())
 377             .parse(in);
 378
 379         return resultHolder.getResult();
 380     }
 381
 382     /**
 383      * Prepare PatchEntity from PatchEdit instance when it satisfies conditions, otherwise throws exception.
 384      * @param edit Instance of PatchEdit
 385      * @return PatchEntity Patch entity
 386      */
 387     private static PatchEntity prepareEditOperation(final @NonNull PatchEdit edit) {
 388         if (edit.getOperation() != null && edit.getTargetSchemaNode() != null
 389                 && checkDataPresence(edit.getOperation(), edit.getData() != null)) {
 390             if (!edit.getOperation().isWithValue()) {
 391                 return new PatchEntity(edit.getId(), edit.getOperation(), edit.getTarget());
 392             }
 393
 394             // for lists allow to manipulate with list items through their parent
 395             final YangInstanceIdentifier targetNode;
 396             if (edit.getTarget().getLastPathArgument() instanceof NodeIdentifierWithPredicates) {
 397                 targetNode = edit.getTarget().getParent();
 398             } else {
 399                 targetNode = edit.getTarget();
 400             }
 401
 402             return new PatchEntity(edit.getId(), edit.getOperation(), targetNode, edit.getData());
 403         }
 404
 405         throw new RestconfDocumentedException("Error parsing input", ErrorType.PROTOCOL, ErrorTag.MALFORMED_MESSAGE);
 406     }
 407
 408     /**
 409      * Check if data is present when operation requires it and not present when operation data is not allowed.
 410      * @param operation Name of operation
 411      * @param hasData Data in edit are present/not present
 412      * @return true if data is present when operation requires it or if there are no data when operation does not
 413      *     allow it, false otherwise
 414      */
 415     private static boolean checkDataPresence(final @NonNull PatchEditOperation operation, final boolean hasData) {
 416         return operation.isWithValue() == hasData;
 417     }
 418
 419     /**
 420      * Helper class representing one patch edit.
 421      */
 422     private static final class PatchEdit {
 423         private String id;
 424         private PatchEditOperation operation;
 425         private YangInstanceIdentifier target;
 426         private SchemaNode targetSchemaNode;
 427         private NormalizedNode data;
 428
 429         String getId() {
 430             return id;
 431         }
 432
 433         void setId(final String id) {
 434             this.id = requireNonNull(id);
 435         }
 436
 437         PatchEditOperation getOperation() {
 438             return operation;
 439         }
 440
 441         void setOperation(final PatchEditOperation operation) {
 442             this.operation = requireNonNull(operation);
 443         }
 444
 445         YangInstanceIdentifier getTarget() {
 446             return target;
 447         }
 448
 449         void setTarget(final YangInstanceIdentifier target) {
 450             this.target = requireNonNull(target);
 451         }
 452
 453         SchemaNode getTargetSchemaNode() {
 454             return targetSchemaNode;
 455         }
 456
 457         void setTargetSchemaNode(final SchemaNode targetSchemaNode) {
 458             this.targetSchemaNode = requireNonNull(targetSchemaNode);
 459         }
 460
 461         NormalizedNode getData() {
 462             return data;
 463         }
 464
 465         void setData(final NormalizedNode data) {
 466             this.data = requireNonNull(data);
 467         }
 468
 469         void clear() {
 470             id = null;
 471             operation = null;
 472             target = null;
 473             targetSchemaNode = null;
 474             data = null;
 475         }
 476     }
 477 }