cps-ri/src/main/java/org/onap/cps/spi/impl/CpsDataPersistenceServiceImpl.java

   1 /*
   2  *  ============LICENSE_START=======================================================
   3  *  Copyright (C) 2021-2022 Nordix Foundation
   4  *  Modifications Copyright (C) 2021 Pantheon.tech
   5  *  Modifications Copyright (C) 2020-2022 Bell Canada.
   6  *  ================================================================================
   7  *  Licensed under the Apache License, Version 2.0 (the "License");
   8  *  you may not use this file except in compliance with the License.
   9  *  You may obtain a copy of the License at
  10  *
  11  *        http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  *  Unless required by applicable law or agreed to in writing, software
  14  *  distributed under the License is distributed on an "AS IS" BASIS,
  15  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  *  See the License for the specific language governing permissions and
  17  *  limitations under the License.
  18  *
  19  *  SPDX-License-Identifier: Apache-2.0
  20  *  ============LICENSE_END=========================================================
  21  */
  22
  23 package org.onap.cps.spi.impl;
  24
  25 import static org.onap.cps.spi.FetchDescendantsOption.INCLUDE_ALL_DESCENDANTS;
  26
  27 import com.google.common.collect.ImmutableSet;
  28 import com.google.common.collect.ImmutableSet.Builder;
  29 import java.util.ArrayList;
  30 import java.util.Collection;
  31 import java.util.Collections;
  32 import java.util.HashMap;
  33 import java.util.HashSet;
  34 import java.util.List;
  35 import java.util.Map;
  36 import java.util.Set;
  37 import java.util.regex.Matcher;
  38 import java.util.regex.Pattern;
  39 import java.util.stream.Collectors;
  40 import javax.transaction.Transactional;
  41 import lombok.RequiredArgsConstructor;
  42 import lombok.extern.slf4j.Slf4j;
  43 import org.hibernate.StaleStateException;
  44 import org.onap.cps.cpspath.parser.CpsPathQuery;
  45 import org.onap.cps.cpspath.parser.CpsPathUtil;
  46 import org.onap.cps.cpspath.parser.PathParsingException;
  47 import org.onap.cps.spi.CpsDataPersistenceService;
  48 import org.onap.cps.spi.FetchDescendantsOption;
  49 import org.onap.cps.spi.entities.AnchorEntity;
  50 import org.onap.cps.spi.entities.DataspaceEntity;
  51 import org.onap.cps.spi.entities.FragmentEntity;
  52 import org.onap.cps.spi.entities.SchemaSetEntity;
  53 import org.onap.cps.spi.entities.YangResourceEntity;
  54 import org.onap.cps.spi.exceptions.AlreadyDefinedException;
  55 import org.onap.cps.spi.exceptions.ConcurrencyException;
  56 import org.onap.cps.spi.exceptions.CpsAdminException;
  57 import org.onap.cps.spi.exceptions.CpsPathException;
  58 import org.onap.cps.spi.exceptions.DataNodeNotFoundException;
  59 import org.onap.cps.spi.model.DataNode;
  60 import org.onap.cps.spi.model.DataNodeBuilder;
  61 import org.onap.cps.spi.repository.AnchorRepository;
  62 import org.onap.cps.spi.repository.DataspaceRepository;
  63 import org.onap.cps.spi.repository.FragmentRepository;
  64 import org.onap.cps.spi.utils.SessionManager;
  65 import org.onap.cps.utils.JsonObjectMapper;
  66 import org.onap.cps.yang.YangTextSchemaSourceSetBuilder;
  67 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  68 import org.springframework.dao.DataIntegrityViolationException;
  69 import org.springframework.stereotype.Service;
  70
  71 @Service
  72 @Slf4j
  73 @RequiredArgsConstructor
  74 public class CpsDataPersistenceServiceImpl implements CpsDataPersistenceService {
  75
  76     private final DataspaceRepository dataspaceRepository;
  77
  78     private final AnchorRepository anchorRepository;
  79
  80     private final FragmentRepository fragmentRepository;
  81
  82     private final JsonObjectMapper jsonObjectMapper;
  83
  84     private final SessionManager sessionManager;
  85
  86     private static final String REG_EX_FOR_OPTIONAL_LIST_INDEX = "(\\[@[\\s\\S]+?]){0,1})";
  87     private static final Pattern REG_EX_PATTERN_FOR_LIST_ELEMENT_KEY_PREDICATE =
  88             Pattern.compile("\\[(\\@([^\\/]{0,9999}))\\]$");
  89
  90     @Override
  91     @Transactional
  92     public void addChildDataNode(final String dataspaceName, final String anchorName, final String parentNodeXpath,
  93                                  final DataNode newChildDataNode) {
  94         addChildDataNodes(dataspaceName, anchorName, parentNodeXpath, Collections.singleton(newChildDataNode));
  95     }
  96
  97     @Override
  98     @Transactional
  99     public void addListElements(final String dataspaceName, final String anchorName, final String parentNodeXpath,
 100                                 final Collection<DataNode> newListElements) {
 101         addChildDataNodes(dataspaceName, anchorName, parentNodeXpath, newListElements);
 102     }
 103
 104     @Override
 105     @Transactional
 106     public void addListElementsBatch(final String dataspaceName, final String anchorName, final String parentNodeXpath,
 107             final Collection<Collection<DataNode>> newListsElements) {
 108
 109         newListsElements.forEach(
 110                 newListElement -> addListElements(dataspaceName, anchorName, parentNodeXpath, newListElement));
 111
 112     }
 113
 114     private void addChildDataNodes(final String dataspaceName, final String anchorName, final String parentNodeXpath,
 115                                    final Collection<DataNode> newChildren) {
 116         final FragmentEntity parentFragmentEntity = getFragmentByXpath(dataspaceName, anchorName, parentNodeXpath);
 117         try {
 118             final List<FragmentEntity> fragmentEntities = new ArrayList<>();
 119             newChildren.forEach(newChildAsDataNode -> {
 120                 final FragmentEntity newChildAsFragmentEntity = convertToFragmentWithAllDescendants(
 121                     parentFragmentEntity.getDataspace(),
 122                     parentFragmentEntity.getAnchor(),
 123                     newChildAsDataNode);
 124                 newChildAsFragmentEntity.setParentId(parentFragmentEntity.getId());
 125                 fragmentEntities.add(newChildAsFragmentEntity);
 126             });
 127             fragmentRepository.saveAll(fragmentEntities);
 128         } catch (final DataIntegrityViolationException exception) {
 129             final List<String> conflictXpaths = newChildren.stream()
 130                     .map(DataNode::getXpath)
 131                     .collect(Collectors.toList());
 132             throw AlreadyDefinedException.forDataNodes(conflictXpaths, anchorName, exception);
 133         }
 134     }
 135
 136     @Override
 137     public void storeDataNode(final String dataspaceName, final String anchorName, final DataNode dataNode) {
 138         final DataspaceEntity dataspaceEntity = dataspaceRepository.getByName(dataspaceName);
 139         final AnchorEntity anchorEntity = anchorRepository.getByDataspaceAndName(dataspaceEntity, anchorName);
 140         final FragmentEntity fragmentEntity = convertToFragmentWithAllDescendants(dataspaceEntity, anchorEntity,
 141                 dataNode);
 142         try {
 143             fragmentRepository.save(fragmentEntity);
 144         } catch (final DataIntegrityViolationException exception) {
 145             throw AlreadyDefinedException.forDataNode(dataNode.getXpath(), anchorName, exception);
 146         }
 147     }
 148
 149     /**
 150      * Convert DataNode object into Fragment and places the result in the fragments placeholder. Performs same action
 151      * for all DataNode children recursively.
 152      *
 153      * @param dataspaceEntity       dataspace
 154      * @param anchorEntity          anchorEntity
 155      * @param dataNodeToBeConverted dataNode
 156      * @return a Fragment built from current DataNode
 157      */
 158     private FragmentEntity convertToFragmentWithAllDescendants(final DataspaceEntity dataspaceEntity,
 159                              final AnchorEntity anchorEntity, final DataNode dataNodeToBeConverted) {
 160         final FragmentEntity parentFragment = toFragmentEntity(dataspaceEntity, anchorEntity, dataNodeToBeConverted);
 161         final Builder<FragmentEntity> childFragmentsImmutableSetBuilder = ImmutableSet.builder();
 162         for (final DataNode childDataNode : dataNodeToBeConverted.getChildDataNodes()) {
 163             final FragmentEntity childFragment =
 164                     convertToFragmentWithAllDescendants(parentFragment.getDataspace(), parentFragment.getAnchor(),
 165                             childDataNode);
 166             childFragmentsImmutableSetBuilder.add(childFragment);
 167         }
 168         parentFragment.setChildFragments(childFragmentsImmutableSetBuilder.build());
 169         return parentFragment;
 170     }
 171
 172     private FragmentEntity toFragmentEntity(final DataspaceEntity dataspaceEntity,
 173                                             final AnchorEntity anchorEntity, final DataNode dataNode) {
 174         return FragmentEntity.builder()
 175                 .dataspace(dataspaceEntity)
 176                 .anchor(anchorEntity)
 177                 .xpath(dataNode.getXpath())
 178                 .attributes(jsonObjectMapper.asJsonString(dataNode.getLeaves()))
 179                 .build();
 180     }
 181
 182     @Override
 183     public DataNode getDataNode(final String dataspaceName, final String anchorName, final String xpath,
 184                                 final FetchDescendantsOption fetchDescendantsOption) {
 185         final FragmentEntity fragmentEntity = getFragmentByXpath(dataspaceName, anchorName, xpath);
 186         return toDataNode(fragmentEntity, fetchDescendantsOption);
 187     }
 188
 189     private FragmentEntity getFragmentByXpath(final String dataspaceName, final String anchorName,
 190                                               final String xpath) {
 191         final DataspaceEntity dataspaceEntity = dataspaceRepository.getByName(dataspaceName);
 192         final AnchorEntity anchorEntity = anchorRepository.getByDataspaceAndName(dataspaceEntity, anchorName);
 193         if (isRootXpath(xpath)) {
 194             return fragmentRepository.findFirstRootByDataspaceAndAnchor(dataspaceEntity, anchorEntity);
 195         } else {
 196             final String normalizedXpath;
 197             try {
 198                 normalizedXpath = CpsPathUtil.getNormalizedXpath(xpath);
 199             } catch (final PathParsingException e) {
 200                 throw new CpsPathException(e.getMessage());
 201             }
 202             return fragmentRepository.getByDataspaceAndAnchorAndXpath(dataspaceEntity, anchorEntity,
 203                     normalizedXpath);
 204         }
 205     }
 206
 207     @Override
 208     public List<DataNode> queryDataNodes(final String dataspaceName, final String anchorName, final String cpsPath,
 209                                          final FetchDescendantsOption fetchDescendantsOption) {
 210         final DataspaceEntity dataspaceEntity = dataspaceRepository.getByName(dataspaceName);
 211         final AnchorEntity anchorEntity = anchorRepository.getByDataspaceAndName(dataspaceEntity, anchorName);
 212         final CpsPathQuery cpsPathQuery;
 213         try {
 214             cpsPathQuery = CpsPathUtil.getCpsPathQuery(cpsPath);
 215         } catch (final PathParsingException e) {
 216             throw new CpsPathException(e.getMessage());
 217         }
 218         List<FragmentEntity> fragmentEntities =
 219                 fragmentRepository.findByAnchorAndCpsPath(anchorEntity.getId(), cpsPathQuery);
 220         if (cpsPathQuery.hasAncestorAxis()) {
 221             final Set<String> ancestorXpaths = processAncestorXpath(fragmentEntities, cpsPathQuery);
 222             fragmentEntities = ancestorXpaths.isEmpty() ? Collections.emptyList()
 223                     : fragmentRepository.findAllByAnchorAndXpathIn(anchorEntity, ancestorXpaths);
 224         }
 225         return fragmentEntities.stream()
 226                 .map(fragmentEntity -> toDataNode(fragmentEntity, fetchDescendantsOption))
 227                 .collect(Collectors.toUnmodifiableList());
 228     }
 229
 230     @Override
 231     public String startSession() {
 232         return sessionManager.startSession();
 233     }
 234
 235     @Override
 236     public void closeSession(final String sessionId) {
 237         sessionManager.closeSession(sessionId, SessionManager.WITH_COMMIT);
 238     }
 239
 240     @Override
 241     public void lockAnchor(final String sessionId, final String dataspaceName,
 242                            final String anchorName, final Long timeoutInMilliseconds) {
 243         sessionManager.lockAnchor(sessionId, dataspaceName, anchorName, timeoutInMilliseconds);
 244     }
 245
 246     private static Set<String> processAncestorXpath(final List<FragmentEntity> fragmentEntities,
 247                                                     final CpsPathQuery cpsPathQuery) {
 248         final Set<String> ancestorXpath = new HashSet<>();
 249         final Pattern pattern =
 250                 Pattern.compile("([\\s\\S]*\\/" + Pattern.quote(cpsPathQuery.getAncestorSchemaNodeIdentifier())
 251                         + REG_EX_FOR_OPTIONAL_LIST_INDEX + "\\/[\\s\\S]*");
 252         for (final FragmentEntity fragmentEntity : fragmentEntities) {
 253             final Matcher matcher = pattern.matcher(fragmentEntity.getXpath());
 254             if (matcher.matches()) {
 255                 ancestorXpath.add(matcher.group(1));
 256             }
 257         }
 258         return ancestorXpath;
 259     }
 260
 261     private DataNode toDataNode(final FragmentEntity fragmentEntity,
 262                                 final FetchDescendantsOption fetchDescendantsOption) {
 263         final List<DataNode> childDataNodes = getChildDataNodes(fragmentEntity, fetchDescendantsOption);
 264         Map<String, Object> leaves = new HashMap<>();
 265         if (fragmentEntity.getAttributes() != null) {
 266             leaves = jsonObjectMapper.convertJsonString(fragmentEntity.getAttributes(), Map.class);
 267         }
 268         return new DataNodeBuilder()
 269                 .withModuleNamePrefix(getFirstModuleName(fragmentEntity))
 270                 .withXpath(fragmentEntity.getXpath())
 271                 .withLeaves(leaves)
 272                 .withChildDataNodes(childDataNodes).build();
 273     }
 274
 275     private String getFirstModuleName(final FragmentEntity fragmentEntity) {
 276         final SchemaSetEntity schemaSetEntity = fragmentEntity.getAnchor().getSchemaSet();
 277         final Map<String, String> yangResourceNameToContent =
 278                 schemaSetEntity.getYangResources().stream().collect(
 279                         Collectors.toMap(YangResourceEntity::getFileName, YangResourceEntity::getContent));
 280         final SchemaContext schemaContext = YangTextSchemaSourceSetBuilder.of(yangResourceNameToContent)
 281                 .getSchemaContext();
 282         return schemaContext.getModules().iterator().next().getName();
 283     }
 284
 285     private List<DataNode> getChildDataNodes(final FragmentEntity fragmentEntity,
 286                                              final FetchDescendantsOption fetchDescendantsOption) {
 287         if (fetchDescendantsOption == INCLUDE_ALL_DESCENDANTS) {
 288             return fragmentEntity.getChildFragments().stream()
 289                     .map(childFragmentEntity -> toDataNode(childFragmentEntity, fetchDescendantsOption))
 290                     .collect(Collectors.toUnmodifiableList());
 291         }
 292         return Collections.emptyList();
 293     }
 294
 295     @Override
 296     public void updateDataLeaves(final String dataspaceName, final String anchorName, final String xpath,
 297                                  final Map<String, Object> leaves) {
 298         final FragmentEntity fragmentEntity = getFragmentByXpath(dataspaceName, anchorName, xpath);
 299         fragmentEntity.setAttributes(jsonObjectMapper.asJsonString(leaves));
 300         fragmentRepository.save(fragmentEntity);
 301     }
 302
 303     @Override
 304     public void updateDataNodeAndDescendants(final String dataspaceName, final String anchorName,
 305                                              final DataNode dataNode) {
 306         final FragmentEntity fragmentEntity = getFragmentByXpath(dataspaceName, anchorName, dataNode.getXpath());
 307         updateFragmentEntityAndDescendantsWithDataNode(fragmentEntity, dataNode);
 308         try {
 309             fragmentRepository.save(fragmentEntity);
 310         } catch (final StaleStateException staleStateException) {
 311             throw new ConcurrencyException("Concurrent Transactions",
 312                     String.format("dataspace :'%s', Anchor : '%s' and xpath: '%s' is updated by another transaction.",
 313                             dataspaceName, anchorName, dataNode.getXpath()),
 314                     staleStateException);
 315         }
 316     }
 317
 318     @Override
 319     public void updateDataNodesAndDescendants(final String dataspaceName,
 320                                               final String anchorName,
 321                                               final List<DataNode> dataNodes) {
 322         final Map<DataNode, FragmentEntity> dataNodeFragmentEntityMap = dataNodes.stream()
 323             .collect(Collectors.toMap(
 324                 dataNode -> dataNode, dataNode -> getFragmentByXpath(dataspaceName, anchorName, dataNode.getXpath())));
 325         dataNodeFragmentEntityMap.forEach(
 326             (dataNode, fragmentEntity) -> updateFragmentEntityAndDescendantsWithDataNode(fragmentEntity, dataNode));
 327         try {
 328             fragmentRepository.saveAll(dataNodeFragmentEntityMap.values());
 329         } catch (final StaleStateException staleStateException) {
 330             throw new ConcurrencyException("Concurrent Transactions",
 331                 String.format("A data node in dataspace :'%s' with Anchor : '%s' is updated by another transaction.",
 332                     dataspaceName, anchorName),
 333                 staleStateException);
 334         }
 335     }
 336
 337     private void updateFragmentEntityAndDescendantsWithDataNode(final FragmentEntity existingFragmentEntity,
 338                                                                 final DataNode newDataNode) {
 339
 340         existingFragmentEntity.setAttributes(jsonObjectMapper.asJsonString(newDataNode.getLeaves()));
 341
 342         final Map<String, FragmentEntity> existingChildrenByXpath = existingFragmentEntity.getChildFragments().stream()
 343                 .collect(Collectors.toMap(FragmentEntity::getXpath, childFragmentEntity -> childFragmentEntity));
 344
 345         final Collection<FragmentEntity> updatedChildFragments = new HashSet<>();
 346
 347         for (final DataNode newDataNodeChild : newDataNode.getChildDataNodes()) {
 348             final FragmentEntity childFragment;
 349             if (isNewDataNode(newDataNodeChild, existingChildrenByXpath)) {
 350                 childFragment = convertToFragmentWithAllDescendants(
 351                         existingFragmentEntity.getDataspace(), existingFragmentEntity.getAnchor(), newDataNodeChild);
 352             } else {
 353                 childFragment = existingChildrenByXpath.get(newDataNodeChild.getXpath());
 354                 updateFragmentEntityAndDescendantsWithDataNode(childFragment, newDataNodeChild);
 355             }
 356             updatedChildFragments.add(childFragment);
 357         }
 358
 359         existingFragmentEntity.getChildFragments().clear();
 360         existingFragmentEntity.getChildFragments().addAll(updatedChildFragments);
 361     }
 362
 363     @Override
 364     @Transactional
 365     public void replaceListContent(final String dataspaceName, final String anchorName, final String parentNodeXpath,
 366                                    final Collection<DataNode> newListElements) {
 367         final FragmentEntity parentEntity = getFragmentByXpath(dataspaceName, anchorName, parentNodeXpath);
 368         final String listElementXpathPrefix = getListElementXpathPrefix(newListElements);
 369         final Map<String, FragmentEntity> existingListElementFragmentEntitiesByXPath =
 370                 extractListElementFragmentEntitiesByXPath(parentEntity.getChildFragments(), listElementXpathPrefix);
 371         deleteListElements(parentEntity.getChildFragments(), existingListElementFragmentEntitiesByXPath);
 372         final Set<FragmentEntity> updatedChildFragmentEntities = new HashSet<>();
 373         for (final DataNode newListElement : newListElements) {
 374             final FragmentEntity existingListElementEntity =
 375                     existingListElementFragmentEntitiesByXPath.get(newListElement.getXpath());
 376             final FragmentEntity entityToBeAdded = getFragmentForReplacement(parentEntity, newListElement,
 377                     existingListElementEntity);
 378
 379             updatedChildFragmentEntities.add(entityToBeAdded);
 380         }
 381         parentEntity.getChildFragments().addAll(updatedChildFragmentEntities);
 382         fragmentRepository.save(parentEntity);
 383     }
 384
 385     @Override
 386     @Transactional
 387     public void deleteDataNodes(final String dataspaceName, final String anchorName) {
 388         final DataspaceEntity dataspaceEntity = dataspaceRepository.getByName(dataspaceName);
 389         anchorRepository.findByDataspaceAndName(dataspaceEntity, anchorName)
 390                 .ifPresent(
 391                         anchorEntity -> fragmentRepository.deleteByAnchorIn(Set.of(anchorEntity)));
 392     }
 393
 394     @Override
 395     @Transactional
 396     public void deleteListDataNode(final String dataspaceName, final String anchorName,
 397                                    final String targetXpath) {
 398         deleteDataNode(dataspaceName, anchorName, targetXpath, true);
 399     }
 400
 401     @Override
 402     @Transactional
 403     public void deleteDataNode(final String dataspaceName, final String anchorName, final String targetXpath) {
 404         deleteDataNode(dataspaceName, anchorName, targetXpath, false);
 405     }
 406
 407     private void deleteDataNode(final String dataspaceName, final String anchorName, final String targetXpath,
 408                                 final boolean onlySupportListNodeDeletion) {
 409         final String parentNodeXpath;
 410         FragmentEntity parentFragmentEntity = null;
 411         boolean targetDeleted = false;
 412         if (isRootXpath(targetXpath)) {
 413             deleteDataNodes(dataspaceName, anchorName);
 414             targetDeleted = true;
 415         } else {
 416             if (isRootContainerNodeXpath(targetXpath)) {
 417                 parentNodeXpath = targetXpath;
 418             } else {
 419                 parentNodeXpath = targetXpath.substring(0, targetXpath.lastIndexOf('/'));
 420             }
 421             parentFragmentEntity = getFragmentByXpath(dataspaceName, anchorName, parentNodeXpath);
 422             final String lastXpathElement = targetXpath.substring(targetXpath.lastIndexOf('/'));
 423             final boolean isListElement = REG_EX_PATTERN_FOR_LIST_ELEMENT_KEY_PREDICATE
 424                     .matcher(lastXpathElement).find();
 425             if (isListElement) {
 426                 targetDeleted = deleteDataNode(parentFragmentEntity, targetXpath);
 427             } else {
 428                 targetDeleted = deleteAllListElements(parentFragmentEntity, targetXpath);
 429                 final boolean tryToDeleteDataNode = !targetDeleted && !onlySupportListNodeDeletion;
 430                 if (tryToDeleteDataNode) {
 431                     targetDeleted = deleteDataNode(parentFragmentEntity, targetXpath);
 432                 }
 433             }
 434         }
 435         if (!targetDeleted) {
 436             final String additionalInformation = onlySupportListNodeDeletion
 437                     ? "The target is probably not a List." : "";
 438             throw new DataNodeNotFoundException(parentFragmentEntity.getDataspace().getName(),
 439                     parentFragmentEntity.getAnchor().getName(), targetXpath, additionalInformation);
 440         }
 441     }
 442
 443     private boolean deleteDataNode(final FragmentEntity parentFragmentEntity, final String targetXpath) {
 444         final String normalizedTargetXpath = CpsPathUtil.getNormalizedXpath(targetXpath);
 445         if (parentFragmentEntity.getXpath().equals(normalizedTargetXpath)) {
 446             fragmentRepository.delete(parentFragmentEntity);
 447             return true;
 448         }
 449         if (parentFragmentEntity.getChildFragments()
 450                 .removeIf(fragment -> fragment.getXpath().equals(normalizedTargetXpath))) {
 451             fragmentRepository.save(parentFragmentEntity);
 452             return true;
 453         }
 454         return false;
 455     }
 456
 457     private boolean deleteAllListElements(final FragmentEntity parentFragmentEntity, final String listXpath) {
 458         final String normalizedListXpath = CpsPathUtil.getNormalizedXpath(listXpath);
 459         final String deleteTargetXpathPrefix = normalizedListXpath + "[";
 460         if (parentFragmentEntity.getChildFragments()
 461                 .removeIf(fragment -> fragment.getXpath().startsWith(deleteTargetXpathPrefix))) {
 462             fragmentRepository.save(parentFragmentEntity);
 463             return true;
 464         }
 465         return false;
 466     }
 467
 468     private static void deleteListElements(
 469             final Collection<FragmentEntity> fragmentEntities,
 470             final Map<String, FragmentEntity> existingListElementFragmentEntitiesByXPath) {
 471         fragmentEntities.removeAll(existingListElementFragmentEntitiesByXPath.values());
 472     }
 473
 474     private static String getListElementXpathPrefix(final Collection<DataNode> newListElements) {
 475         if (newListElements.isEmpty()) {
 476             throw new CpsAdminException("Invalid list replacement",
 477                     "Cannot replace list elements with empty collection");
 478         }
 479         final String firstChildNodeXpath = newListElements.iterator().next().getXpath();
 480         return firstChildNodeXpath.substring(0, firstChildNodeXpath.lastIndexOf('[') + 1);
 481     }
 482
 483     private FragmentEntity getFragmentForReplacement(final FragmentEntity parentEntity,
 484                                                      final DataNode newListElement,
 485                                                      final FragmentEntity existingListElementEntity) {
 486         if (existingListElementEntity == null) {
 487             return convertToFragmentWithAllDescendants(
 488                     parentEntity.getDataspace(), parentEntity.getAnchor(), newListElement);
 489         }
 490         if (newListElement.getChildDataNodes().isEmpty()) {
 491             copyAttributesFromNewListElement(existingListElementEntity, newListElement);
 492             existingListElementEntity.getChildFragments().clear();
 493         } else {
 494             updateFragmentEntityAndDescendantsWithDataNode(existingListElementEntity, newListElement);
 495         }
 496         return existingListElementEntity;
 497     }
 498
 499     private static boolean isNewDataNode(final DataNode replacementDataNode,
 500                                          final Map<String, FragmentEntity> existingListElementsByXpath) {
 501         return !existingListElementsByXpath.containsKey(replacementDataNode.getXpath());
 502     }
 503
 504     private static boolean isRootContainerNodeXpath(final String xpath) {
 505         return 0 == xpath.lastIndexOf('/');
 506     }
 507
 508     private void copyAttributesFromNewListElement(final FragmentEntity existingListElementEntity,
 509                                                   final DataNode newListElement) {
 510         final FragmentEntity replacementFragmentEntity =
 511                 FragmentEntity.builder().attributes(jsonObjectMapper.asJsonString(
 512                         newListElement.getLeaves())).build();
 513         existingListElementEntity.setAttributes(replacementFragmentEntity.getAttributes());
 514     }
 515
 516     private static Map<String, FragmentEntity> extractListElementFragmentEntitiesByXPath(
 517             final Set<FragmentEntity> childEntities, final String listElementXpathPrefix) {
 518         return childEntities.stream()
 519                 .filter(fragmentEntity -> fragmentEntity.getXpath().startsWith(listElementXpathPrefix))
 520                 .collect(Collectors.toMap(FragmentEntity::getXpath, fragmentEntity -> fragmentEntity));
 521     }
 522
 523     private static boolean isRootXpath(final String xpath) {
 524         return "/".equals(xpath) || "".equals(xpath);
 525     }
 526 }