restconf/restconf-nb-rfc8040/src/main/java/org/opendaylight/restconf/nb/rfc8040/jersey/providers/patch/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.nb.rfc8040.jersey.providers.patch;
  10
  11 import com.google.common.base.Optional;
  12 import com.google.common.base.Preconditions;
  13 import com.google.common.collect.ImmutableList;
  14 import com.google.gson.stream.JsonReader;
  15 import com.google.gson.stream.JsonToken;
  16 import java.io.IOException;
  17 import java.io.InputStream;
  18 import java.io.InputStreamReader;
  19 import java.io.StringReader;
  20 import java.nio.charset.StandardCharsets;
  21 import java.util.ArrayList;
  22 import java.util.List;
  23 import java.util.Locale;
  24 import java.util.concurrent.atomic.AtomicReference;
  25 import javax.annotation.Nonnull;
  26 import javax.ws.rs.Consumes;
  27 import javax.ws.rs.WebApplicationException;
  28 import javax.ws.rs.ext.Provider;
  29 import org.opendaylight.restconf.common.context.InstanceIdentifierContext;
  30 import org.opendaylight.restconf.common.errors.RestconfDocumentedException;
  31 import org.opendaylight.restconf.common.errors.RestconfError.ErrorTag;
  32 import org.opendaylight.restconf.common.errors.RestconfError.ErrorType;
  33 import org.opendaylight.restconf.common.patch.PatchContext;
  34 import org.opendaylight.restconf.common.patch.PatchEditOperation;
  35 import org.opendaylight.restconf.common.patch.PatchEntity;
  36 import org.opendaylight.restconf.nb.rfc8040.Rfc8040;
  37 import org.opendaylight.restconf.nb.rfc8040.codecs.StringModuleInstanceIdentifierCodec;
  38 import org.opendaylight.restconf.nb.rfc8040.handlers.DOMMountPointServiceHandler;
  39 import org.opendaylight.restconf.nb.rfc8040.handlers.SchemaContextHandler;
  40 import org.opendaylight.restconf.nb.rfc8040.utils.RestconfConstants;
  41 import org.opendaylight.restconf.nb.rfc8040.utils.parser.ParserIdentifier;
  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.api.SchemaNode;
  52 import org.opendaylight.yangtools.yang.model.util.SchemaContextUtil;
  53 import org.slf4j.Logger;
  54 import org.slf4j.LoggerFactory;
  55
  56 @Provider
  57 @Consumes({Rfc8040.MediaTypes.PATCH + RestconfConstants.JSON})
  58 public class JsonToPatchBodyReader extends AbstractToPatchBodyReader {
  59     private static final Logger LOG = LoggerFactory.getLogger(JsonToPatchBodyReader.class);
  60
  61     public JsonToPatchBodyReader(SchemaContextHandler schemaContextHandler,
  62             DOMMountPointServiceHandler mountPointServiceHandler) {
  63         super(schemaContextHandler, mountPointServiceHandler);
  64     }
  65
  66     @SuppressWarnings("checkstyle:IllegalCatch")
  67     @Override
  68     protected PatchContext readBody(final InstanceIdentifierContext<?> path, final InputStream entityStream)
  69             throws IOException, 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.fromNullable(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         if (exception instanceof RestconfDocumentedException) {
 102             throw (RestconfDocumentedException)exception;
 103         }
 104
 105         if (exception instanceof ResultAlreadySetException) {
 106             LOG.debug("Error parsing json input:", exception);
 107             throw new RestconfDocumentedException("Error parsing json input: Failed to create new parse result data. ");
 108         }
 109
 110         throw new RestconfDocumentedException("Error parsing json input: " + exception.getMessage(), ErrorType.PROTOCOL,
 111                 ErrorTag.MALFORMED_MESSAGE, exception);
 112     }
 113
 114     private List<PatchEntity> read(final JsonReader in, final InstanceIdentifierContext<?> path,
 115             final AtomicReference<String> patchId) throws IOException {
 116         final List<PatchEntity> resultCollection = new ArrayList<>();
 117         final StringModuleInstanceIdentifierCodec codec = new StringModuleInstanceIdentifierCodec(
 118                 path.getSchemaContext());
 119         final JsonToPatchBodyReader.PatchEdit edit = new JsonToPatchBodyReader.PatchEdit();
 120
 121         while (in.hasNext()) {
 122             switch (in.peek()) {
 123                 case STRING:
 124                 case NUMBER:
 125                     in.nextString();
 126                     break;
 127                 case BOOLEAN:
 128                     Boolean.toString(in.nextBoolean());
 129                     break;
 130                 case NULL:
 131                     in.nextNull();
 132                     break;
 133                 case BEGIN_ARRAY:
 134                     in.beginArray();
 135                     break;
 136                 case BEGIN_OBJECT:
 137                     in.beginObject();
 138                     break;
 139                 case END_DOCUMENT:
 140                     break;
 141                 case NAME:
 142                     parseByName(in.nextName(), edit, in, path, codec, resultCollection, patchId);
 143                     break;
 144                 case END_OBJECT:
 145                     in.endObject();
 146                     break;
 147                 case END_ARRAY:
 148                     in.endArray();
 149                     break;
 150
 151                 default:
 152                     break;
 153             }
 154         }
 155
 156         return ImmutableList.copyOf(resultCollection);
 157     }
 158
 159     /**
 160      * Switch value of parsed JsonToken.NAME and read edit definition or patch id.
 161      *
 162      * @param name value of token
 163      * @param edit PatchEdit instance
 164      * @param in JsonReader reader
 165      * @param path InstanceIdentifierContext context
 166      * @param codec Draft11StringModuleInstanceIdentifierCodec codec
 167      * @param resultCollection collection of parsed edits
 168      * @throws IOException if operation fails
 169      */
 170     private void parseByName(@Nonnull final String name, @Nonnull final PatchEdit edit,
 171                              @Nonnull final JsonReader in, @Nonnull final InstanceIdentifierContext<?> path,
 172                              @Nonnull final StringModuleInstanceIdentifierCodec codec,
 173                              @Nonnull final List<PatchEntity> resultCollection,
 174                              @Nonnull final AtomicReference<String> patchId) throws IOException {
 175         switch (name) {
 176             case "edit":
 177                 if (in.peek() == JsonToken.BEGIN_ARRAY) {
 178                     in.beginArray();
 179
 180                     while (in.hasNext()) {
 181                         readEditDefinition(edit, in, path, codec);
 182                         resultCollection.add(prepareEditOperation(edit));
 183                         edit.clear();
 184                     }
 185
 186                     in.endArray();
 187                 } else {
 188                     readEditDefinition(edit, in, path, codec);
 189                     resultCollection.add(prepareEditOperation(edit));
 190                     edit.clear();
 191                 }
 192
 193                 break;
 194             case "patch-id":
 195                 patchId.set(in.nextString());
 196                 break;
 197             default:
 198                 break;
 199         }
 200     }
 201
 202     /**
 203      * Read one patch edit object from Json input.
 204      *
 205      * @param edit PatchEdit instance to be filled with read data
 206      * @param in JsonReader reader
 207      * @param path InstanceIdentifierContext path context
 208      * @param codec Draft11StringModuleInstanceIdentifierCodec codec
 209      * @throws IOException if operation fails
 210      */
 211     private void readEditDefinition(@Nonnull final PatchEdit edit, @Nonnull final JsonReader in,
 212                                     @Nonnull final InstanceIdentifierContext<?> path,
 213                                     @Nonnull final StringModuleInstanceIdentifierCodec codec) throws IOException {
 214         String deferredValue = null;
 215         in.beginObject();
 216
 217         while (in.hasNext()) {
 218             final String editDefinition = in.nextName();
 219             switch (editDefinition) {
 220                 case "edit-id":
 221                     edit.setId(in.nextString());
 222                     break;
 223                 case "operation":
 224                     edit.setOperation(PatchEditOperation.valueOf(in.nextString().toUpperCase(Locale.ROOT)));
 225                     break;
 226                 case "target":
 227                     // target can be specified completely in request URI
 228                     final String target = in.nextString();
 229                     if (target.equals("/")) {
 230                         edit.setTarget(path.getInstanceIdentifier());
 231                         edit.setTargetSchemaNode(path.getSchemaContext());
 232                     } else {
 233                         edit.setTarget(codec.deserialize(codec.serialize(path.getInstanceIdentifier()).concat(target)));
 234                         edit.setTargetSchemaNode(SchemaContextUtil.findDataSchemaNode(path.getSchemaContext(),
 235                                 codec.getDataContextTree().getChild(edit.getTarget()).getDataSchemaNode().getPath()
 236                                         .getParent()));
 237                     }
 238
 239                     break;
 240                 case "value":
 241                     Preconditions.checkArgument(edit.getData() == null && deferredValue == null,
 242                             "Multiple value entries found");
 243
 244                     if (edit.getTargetSchemaNode() == null) {
 245                         final StringBuilder sb = new StringBuilder();
 246
 247                         // save data defined in value node for next (later) processing, because target needs to be read
 248                         // always first and there is no ordering in Json input
 249                         readValueNode(sb, in);
 250                         deferredValue = sb.toString();
 251                     } else {
 252                         // We have a target schema node, reuse this reader without buffering the value.
 253                         edit.setData(readEditData(in, edit.getTargetSchemaNode(), path));
 254                     }
 255                     break;
 256                 default:
 257                     // FIXME: this does not look right, as it can wreck our logic
 258                     break;
 259             }
 260         }
 261
 262         in.endObject();
 263
 264         if (deferredValue != null) {
 265             // read saved data to normalized node when target schema is already known
 266             edit.setData(readEditData(new JsonReader(new StringReader(deferredValue)), edit.getTargetSchemaNode(),
 267                 path));
 268         }
 269     }
 270
 271     /**
 272      * Parse data defined in value node and saves it to buffer.
 273      * @param sb Buffer to read value node
 274      * @param in JsonReader reader
 275      * @throws IOException if operation fails
 276      */
 277     private void readValueNode(@Nonnull final StringBuilder sb, @Nonnull final JsonReader in) throws IOException {
 278         in.beginObject();
 279
 280         sb.append("{\"").append(in.nextName()).append("\":");
 281
 282         switch (in.peek()) {
 283             case BEGIN_ARRAY:
 284                 in.beginArray();
 285                 sb.append('[');
 286
 287                 while (in.hasNext()) {
 288                     if (in.peek() == JsonToken.STRING) {
 289                         sb.append('"').append(in.nextString()).append('"');
 290                     } else {
 291                         readValueObject(sb, in);
 292                     }
 293                     if (in.peek() != JsonToken.END_ARRAY) {
 294                         sb.append(',');
 295                     }
 296                 }
 297
 298                 in.endArray();
 299                 sb.append(']');
 300                 break;
 301             default:
 302                 readValueObject(sb, in);
 303                 break;
 304         }
 305
 306         in.endObject();
 307         sb.append('}');
 308     }
 309
 310     /**
 311      * Parse one value object of data and saves it to buffer.
 312      * @param sb Buffer to read value object
 313      * @param in JsonReader reader
 314      * @throws IOException if operation fails
 315      */
 316     private void readValueObject(@Nonnull final StringBuilder sb, @Nonnull final JsonReader in) throws IOException {
 317         // read simple leaf value
 318         if (in.peek() == JsonToken.STRING) {
 319             sb.append('"').append(in.nextString()).append('"');
 320             return;
 321         }
 322
 323         in.beginObject();
 324         sb.append('{');
 325
 326         while (in.hasNext()) {
 327             sb.append('"').append(in.nextName()).append("\":");
 328
 329             switch (in.peek()) {
 330                 case STRING:
 331                     sb.append('"').append(in.nextString()).append('"');
 332                     break;
 333                 case BEGIN_ARRAY:
 334                     in.beginArray();
 335                     sb.append('[');
 336
 337                     while (in.hasNext()) {
 338                         if (in.peek() == JsonToken.STRING) {
 339                             sb.append('"').append(in.nextString()).append('"');
 340                         } else {
 341                             readValueObject(sb, in);
 342                         }
 343
 344                         if (in.peek() != JsonToken.END_ARRAY) {
 345                             sb.append(',');
 346                         }
 347                     }
 348
 349                     in.endArray();
 350                     sb.append(']');
 351                     break;
 352                 default:
 353                     readValueObject(sb, in);
 354             }
 355
 356             if (in.peek() != JsonToken.END_OBJECT) {
 357                 sb.append(',');
 358             }
 359         }
 360
 361         in.endObject();
 362         sb.append('}');
 363     }
 364
 365     /**
 366      * Read patch edit data defined in value node to NormalizedNode.
 367      * @param in reader JsonReader reader
 368      * @return NormalizedNode representing data
 369      */
 370     private static NormalizedNode<?, ?> readEditData(@Nonnull final JsonReader in,
 371             @Nonnull final SchemaNode targetSchemaNode, @Nonnull final InstanceIdentifierContext<?> path) {
 372         final NormalizedNodeResult resultHolder = new NormalizedNodeResult();
 373         final NormalizedNodeStreamWriter writer = ImmutableNormalizedNodeStreamWriter.from(resultHolder);
 374         JsonParserStream.create(writer, JSONCodecFactorySupplier.RFC7951.getShared(path.getSchemaContext()),
 375             targetSchemaNode).parse(in);
 376
 377         return resultHolder.getResult();
 378     }
 379
 380     /**
 381      * Prepare PatchEntity from PatchEdit instance when it satisfies conditions, otherwise throws exception.
 382      * @param edit Instance of PatchEdit
 383      * @return PatchEntity Patch entity
 384      */
 385     private static PatchEntity prepareEditOperation(@Nonnull final PatchEdit edit) {
 386         if (edit.getOperation() != null && edit.getTargetSchemaNode() != null
 387                 && checkDataPresence(edit.getOperation(), edit.getData() != null)) {
 388             if (!edit.getOperation().isWithValue()) {
 389                 return new PatchEntity(edit.getId(), edit.getOperation(), edit.getTarget());
 390             }
 391
 392             // for lists allow to manipulate with list items through their parent
 393             final YangInstanceIdentifier targetNode;
 394             if (edit.getTarget().getLastPathArgument() instanceof NodeIdentifierWithPredicates) {
 395                 targetNode = edit.getTarget().getParent();
 396             } else {
 397                 targetNode = edit.getTarget();
 398             }
 399
 400             return new PatchEntity(edit.getId(), edit.getOperation(), targetNode, edit.getData());
 401         }
 402
 403         throw new RestconfDocumentedException("Error parsing input", ErrorType.PROTOCOL, ErrorTag.MALFORMED_MESSAGE);
 404     }
 405
 406     /**
 407      * Check if data is present when operation requires it and not present when operation data is not allowed.
 408      * @param operation Name of operation
 409      * @param hasData Data in edit are present/not present
 410      * @return true if data is present when operation requires it or if there are no data when operation does not
 411      *     allow it, false otherwise
 412      */
 413     private static boolean checkDataPresence(@Nonnull final PatchEditOperation operation, final boolean hasData) {
 414         return operation.isWithValue() == hasData;
 415     }
 416
 417     /**
 418      * Helper class representing one patch edit.
 419      */
 420     private static final class PatchEdit {
 421         private String id;
 422         private PatchEditOperation operation;
 423         private YangInstanceIdentifier target;
 424         private SchemaNode targetSchemaNode;
 425         private NormalizedNode<?, ?> data;
 426
 427         String getId() {
 428             return id;
 429         }
 430
 431         void setId(final String id) {
 432             this.id = Preconditions.checkNotNull(id);
 433         }
 434
 435         PatchEditOperation getOperation() {
 436             return operation;
 437         }
 438
 439         void setOperation(final PatchEditOperation operation) {
 440             this.operation = Preconditions.checkNotNull(operation);
 441         }
 442
 443         YangInstanceIdentifier getTarget() {
 444             return target;
 445         }
 446
 447         void setTarget(final YangInstanceIdentifier target) {
 448             this.target = Preconditions.checkNotNull(target);
 449         }
 450
 451         SchemaNode getTargetSchemaNode() {
 452             return targetSchemaNode;
 453         }
 454
 455         void setTargetSchemaNode(final SchemaNode targetSchemaNode) {
 456             this.targetSchemaNode = Preconditions.checkNotNull(targetSchemaNode);
 457         }
 458
 459         NormalizedNode<?, ?> getData() {
 460             return data;
 461         }
 462
 463         void setData(final NormalizedNode<?, ?> data) {
 464             this.data = Preconditions.checkNotNull(data);
 465         }
 466
 467         void clear() {
 468             id = null;
 469             operation = null;
 470             target = null;
 471             targetSchemaNode = null;
 472             data = null;
 473         }
 474     }
 475 }