content: /**
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   * <p>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p>
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.atlas.repository.store.graph.v2;
  
  import org.apache.atlas.AtlasErrorCode;
  import org.apache.atlas.RequestContext;
  import org.apache.atlas.exception.AtlasBaseException;
  import org.apache.atlas.model.TypeCategory;
  import org.apache.atlas.model.instance.AtlasEntity;
  import org.apache.atlas.repository.graphdb.AtlasGraph;
  import org.apache.atlas.repository.graphdb.AtlasVertex;
  import org.apache.atlas.repository.store.graph.EntityGraphDiscoveryContext;
  import org.apache.atlas.repository.store.graph.EntityResolver;
  import org.apache.atlas.type.AtlasEntityType;
  import org.apache.atlas.type.AtlasTypeRegistry;
  import org.apache.atlas.type.AtlasTypeUtil;
  
  public class IDBasedEntityResolver implements EntityResolver {
      private final AtlasGraph        graph;
      private final AtlasTypeRegistry typeRegistry;
      private final EntityGraphMapper entityGraphMapper;
  
      public IDBasedEntityResolver(AtlasGraph graph, AtlasTypeRegistry typeRegistry) {
          this(graph, typeRegistry, null);
      }
  
      public IDBasedEntityResolver(AtlasGraph graph, AtlasTypeRegistry typeRegistry, EntityGraphMapper entityGraphMapper) {
          this.graph             = graph;
          this.typeRegistry      = typeRegistry;
          this.entityGraphMapper = entityGraphMapper;
      }
  
      public EntityGraphDiscoveryContext resolveEntityReferences(EntityGraphDiscoveryContext context) throws AtlasBaseException {
          if (context == null) {
              throw new AtlasBaseException(AtlasErrorCode.INTERNAL_ERROR, "IDBasedEntityResolver.resolveEntityReferences(): context is null");
          }
  
          EntityStream entityStream = context.getEntityStream();
  
          for (String guid : context.getReferencedGuids()) {
              boolean     isAssignedGuid = AtlasTypeUtil.isAssignedGuid(guid);
              AtlasVertex vertex         = isAssignedGuid ? AtlasGraphUtilsV2.findByGuid(this.graph, guid) : null;
  
              if (vertex == null) { // if not found in the store, look if the entity is present in the stream
                  AtlasEntity entity = entityStream.getByGuid(guid);
  
                  if (!RequestContext.get().isImportInProgress()) {
                      if (entity != null) { // look for the entity in the store using unique-attributes
                          AtlasEntityType entityType = typeRegistry.getEntityTypeByName(entity.getTypeName());
  
                          if (entityType == null) {
                              throw new AtlasBaseException(AtlasErrorCode.TYPE_NAME_INVALID, TypeCategory.ENTITY.name(), entity.getTypeName());
                          }
  
                          vertex = AtlasGraphUtilsV2.findByUniqueAttributes(this.graph, entityType, entity.getAttributes());
                      } else if (!isAssignedGuid) { // for local-guids, entity must be in the stream
                          throw new AtlasBaseException(AtlasErrorCode.REFERENCED_ENTITY_NOT_FOUND, guid);
                      }
                  } else if (entity != null && entity.getIsIncomplete() != null && entity.getIsIncomplete()) {
                      if (entityGraphMapper != null) {
                          vertex = entityGraphMapper.createShellEntityVertex(entity, context);
                      }
                  }
              }
  
              if (vertex != null) {
                  context.addResolvedGuid(guid, vertex);
              } else {
                  if (isAssignedGuid && !RequestContext.get().isImportInProgress()) {
                      throw new AtlasBaseException(AtlasErrorCode.REFERENCED_ENTITY_NOT_FOUND, guid);
                  } else {
                      context.addLocalGuidReference(guid);
                  }
              }
          }
  
          return context;
      }
  }
  