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.impexp;
  
  import com.fasterxml.jackson.core.JsonFactory;
  import com.fasterxml.jackson.core.JsonParser;
  import com.fasterxml.jackson.core.JsonToken;
  import com.fasterxml.jackson.databind.JsonNode;
  import org.apache.atlas.entitytransform.BaseEntityHandler;
  import org.apache.atlas.exception.AtlasBaseException;
  import org.apache.atlas.model.impexp.AtlasExportResult;
  import org.apache.atlas.model.instance.AtlasEntity;
  import org.apache.atlas.model.typedef.AtlasTypesDef;
  import org.apache.atlas.repository.store.graph.v2.EntityImportStream;
  import org.apache.atlas.type.AtlasType;
  import org.apache.atlas.utils.AtlasJson;
  import org.apache.commons.collections.MapUtils;
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.lang.StringUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.ByteArrayOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.zip.ZipEntry;
  import java.util.zip.ZipInputStream;
  
  import static org.apache.atlas.AtlasErrorCode.IMPORT_ATTEMPTING_EMPTY_ZIP;
  
  public class ZipSourceDirect implements EntityImportStream {
      private static final Logger LOG = LoggerFactory.getLogger(ZipSourceDirect.class);
  
      private static final String ZIP_ENTRY_ENTITIES = "entities.json";
  
      private final ZipInputStream          zipInputStream;
      private       EntitiesArrayParser     entitiesArrayParser;
      private       int                     currentPosition;
      private       ImportTransforms        importTransform;
      private       List<BaseEntityHandler> entityHandlers;
      private       AtlasTypesDef           typesDef;
      private final int                     streamSize;
  
      public ZipSourceDirect(InputStream inputStream, int streamSize) throws IOException, AtlasBaseException {
          this.zipInputStream = new ZipInputStream(inputStream);
          this.streamSize     = streamSize;
  
          prepareStreamForFetch();
  
          if (this.streamSize == 1) {
              LOG.info("ZipSourceDirect: Stream Size set to: {}. This will cause inaccurate percentage reporting.", this.streamSize);
          }
      }
  
      @Override
      public boolean hasNext() {
          return (this.entitiesArrayParser != null && entitiesArrayParser.hasNext());
      }
  
      @Override
      public AtlasEntity next() {
          AtlasEntity.AtlasEntityWithExtInfo entityWithExtInfo = getNextEntityWithExtInfo();
  
          return entityWithExtInfo != null ? entityWithExtInfo.getEntity() : null;
      }
  
      @Override
      public void reset() {
          currentPosition = 0;
      }
  
      @Override
      public AtlasEntity getByGuid(String guid) {
          try {
              return getEntity(guid);
          } catch (AtlasBaseException e) {
              LOG.error("getByGuid: {} failed!", guid, e);
              return null;
          }
      }
  
      public int size() {
          if (this.streamSize == 1) {
              return currentPosition;
          }
  
          return this.streamSize;
      }
  
      @Override
      public int getPosition() {
          return currentPosition;
      }
  
      @Override
      public void setPosition(int index) {
          for (int i = 0; i < index; i++) {
              moveNext();
          }
      }
  
      @Override
      public void setPositionUsingEntityGuid(String guid) {
      }
  
      @Override
      public AtlasEntity.AtlasEntityWithExtInfo getNextEntityWithExtInfo() {
          try {
              if (hasNext()) {
                  String json = moveNext();
  
                  return getEntityWithExtInfo(json);
              }
          } catch (AtlasBaseException e) {
              LOG.error("getNextEntityWithExtInfo", e);
          }
  
          return null;
      }
  
      @Override
      public AtlasEntity.AtlasEntityWithExtInfo getEntityWithExtInfo(String json) throws AtlasBaseException {
          if (StringUtils.isEmpty(json)) {
              return null;
          }
  
          AtlasEntity.AtlasEntityWithExtInfo entityWithExtInfo = convertFromJson(AtlasEntity.AtlasEntityWithExtInfo.class, json);
  
          if (importTransform != null) {
              entityWithExtInfo = importTransform.apply(entityWithExtInfo);
          }
  
          if (entityHandlers != null) {
              applyTransformers(entityWithExtInfo);
          }
  
          return entityWithExtInfo;
      }
  
      @Override
      public void onImportComplete(String guid) {
      }
  
      @Override
      public ImportTransforms getImportTransform() {
          return this.importTransform;
      }
  
      @Override
      public void setImportTransform(ImportTransforms importTransform) {
          this.importTransform = importTransform;
      }
  
      @Override
      public List<BaseEntityHandler> getEntityHandlers() {
          return entityHandlers;
      }
  
      @Override
      public void setEntityHandlers(List<BaseEntityHandler> entityHandlers) {
          this.entityHandlers = entityHandlers;
      }
  
      @Override
      public AtlasTypesDef getTypesDef() throws AtlasBaseException {
          return this.typesDef;
      }
  
      @Override
      public AtlasExportResult getExportResult() throws AtlasBaseException {
          return new AtlasExportResult();
      }
  
      @Override
      public List<String> getCreationOrder() {
          return new ArrayList<>();
      }
  
      @Override
      public void close() {
          if (this.entitiesArrayParser != null) {
              this.entitiesArrayParser.close();
          }
      }
  
      @Override
      public String getMd5Hash() {
          return null;
      }
  
      private void applyTransformers(AtlasEntity.AtlasEntityWithExtInfo entityWithExtInfo) {
          if (entityWithExtInfo == null) {
              return;
          }
  
          transform(entityWithExtInfo.getEntity());
  
          if (MapUtils.isNotEmpty(entityWithExtInfo.getReferredEntities())) {
              for (AtlasEntity e : entityWithExtInfo.getReferredEntities().values()) {
                  transform(e);
              }
          }
      }
  
      private void transform(AtlasEntity e) {
          for (BaseEntityHandler handler : entityHandlers) {
              handler.transform(e);
          }
      }
  
      private <T> T convertFromJson(Class<T> clazz, String jsonData) throws AtlasBaseException {
          try {
              return AtlasType.fromJson(jsonData, clazz);
          } catch (Exception e) {
              throw new AtlasBaseException("Error converting file to JSON.", e);
          }
      }
  
      private AtlasEntity getEntity(String guid) throws AtlasBaseException {
          AtlasEntity.AtlasEntityWithExtInfo extInfo = getEntityWithExtInfo(guid);
  
          return (extInfo != null) ? extInfo.getEntity() : null;
      }
  
      private String moveNext() {
          try {
              moveNextEntry();
  
              return entitiesArrayParser.next();
          } catch (IOException e) {
              LOG.error("moveNext failed!", e);
          }
  
          return null;
      }
  
      private void moveNextEntry() throws IOException {
          this.currentPosition++;
      }
  
      private void prepareStreamForFetch() throws AtlasBaseException, IOException {
          ZipEntry zipEntryNext = zipInputStream.getNextEntry();
  
          if (zipEntryNext == null) {
              throw new AtlasBaseException(IMPORT_ATTEMPTING_EMPTY_ZIP, "Attempting to import empty ZIP.");
          }
  
          if (zipEntryNext.getName().equals(ZipExportFileNames.ATLAS_TYPESDEF_NAME.toEntryFileName())) {
              String json = getJsonPayloadFromZipEntryStream(this.zipInputStream);
  
              this.typesDef = AtlasType.fromJson(json, AtlasTypesDef.class);
  
              zipEntryNext  = zipInputStream.getNextEntry();
          }
  
          if (zipEntryNext.getName().equals(ZIP_ENTRY_ENTITIES)) {
              this.entitiesArrayParser = new EntitiesArrayParser(zipInputStream);
          } else {
              throw new AtlasBaseException(IMPORT_ATTEMPTING_EMPTY_ZIP, "Attempting to import empty ZIP. " + ZIP_ENTRY_ENTITIES + " could not be found!");
          }
      }
  
      private String getJsonPayloadFromZipEntryStream(ZipInputStream zipInputStream) {
          ByteArrayOutputStream bos = new ByteArrayOutputStream();
  
          try {
              IOUtils.copy(zipInputStream, bos);
          } catch (IOException e) {
              LOG.error("Streaming copying failed!", e);
              return null;
          }
  
          return bos.toString();
      }
  
      static class EntitiesArrayParser {
          private static final String EMPTY_OBJECT = "{}";
  
          private final JsonFactory factory;
          private final JsonParser  parser;
          private       boolean     hasNext;
  
          public EntitiesArrayParser(InputStream inputStream) throws IOException {
              this.factory = AtlasJson.getMapper().getFactory();
              this.parser  = factory.createParser(inputStream);
  
              parseNext();
          }
  
          public String next() throws IOException {
              JsonToken jsonToken = parseNext();
  
              if (!hasNext) {
                  return null;
              }
  
              if (jsonToken == JsonToken.START_OBJECT) {
                  JsonNode node = parser.readValueAsTree();
  
                  return validate(node.toString());
              }
  
              return null;
          }
  
          public boolean hasNext() {
              return hasNext;
          }
  
          public void close() {
              try {
                  this.parser.close();
              } catch (IOException e) {
                  LOG.error("Error closing parser!", e);
              }
          }
  
          private JsonToken parseNext() throws IOException {
              JsonToken jsonToken = this.parser.nextToken();
  
              hasNext = (jsonToken != null) && (jsonToken != JsonToken.END_ARRAY);
  
              return jsonToken;
          }
  
          private String validate(String payload) {
              if (payload.equals(EMPTY_OBJECT)) {
                  hasNext = false;
  
                  close();
  
                  return null;
              }
  
              return payload;
          }
      }
  }
  