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