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.graphdb.janus.migration;
  
  import com.google.common.annotations.VisibleForTesting;
  import org.apache.atlas.model.impexp.MigrationStatus;
  import org.apache.atlas.repository.Constants;
  import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversal;
  import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource;
  import org.apache.tinkerpop.gremlin.structure.Graph;
  import org.apache.tinkerpop.gremlin.structure.Vertex;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.Date;
  
  public class ReaderStatusManager {
      private static final Logger LOG = LoggerFactory.getLogger(ReaderStatusManager.class);
  
      public static final String STATUS_NOT_STARTED = "NOT_STARTED";
      public static final String STATUS_IN_PROGRESS = "IN_PROGRESS";
      public static final String STATUS_SUCCESS     = "SUCCESS";
      public static final String STATUS_FAILED      = "FAILED";
  
      private static final String MIGRATION_STATUS_TYPE_NAME = "__MigrationStatus";
      private static final String CURRENT_INDEX_PROPERTY     = "currentIndex";
      private static final String CURRENT_COUNTER_PROPERTY   = "currentCounter";
      private static final String OPERATION_STATUS_PROPERTY  = "operationStatus";
      private static final String START_TIME_PROPERTY        = "startTime";
      private static final String END_TIME_PROPERTY          = "endTime";
      private static final String TOTAL_COUNT_PROPERTY       = "totalCount";
  
      @VisibleForTesting
      Object migrationStatusId;
  
      private Vertex migrationStatus;
  
      public ReaderStatusManager(Graph graph, Graph bulkLoadGraph) {
          init(graph, bulkLoadGraph);
      }
  
      public static MigrationStatus get(Graph graph) {
          MigrationStatus ms = new MigrationStatus();
  
          try {
              setValues(ms, fetchUsingTypeName(graph.traversal()));
          } catch (Exception ex) {
              if (LOG.isDebugEnabled()) {
                  LOG.error("get: failed!", ex);
              }
          }
  
          return ms;
      }
  
      public void init(Graph graph, Graph bulkLoadGraph) {
          migrationStatus = fetchUsingTypeName(bulkLoadGraph.traversal());
  
          if (migrationStatus == null) {
              createAndCommit(graph);
  
              migrationStatus = fetchUsingId(bulkLoadGraph.traversal());
          }
  
          if (migrationStatus == null) {
              migrationStatus = fetchUsingId(bulkLoadGraph.traversal());
          }
      }
  
      public void end(Graph bGraph, Long counter, String status) {
          migrationStatus.property(END_TIME_PROPERTY, new Date());
          migrationStatus.property(TOTAL_COUNT_PROPERTY, counter);
  
          update(bGraph, counter, status);
      }
  
      public void update(Graph graph, Long counter, boolean stageEnd) {
          migrationStatus.property(CURRENT_COUNTER_PROPERTY, counter);
  
          if (stageEnd) {
              migrationStatus.property(CURRENT_INDEX_PROPERTY, counter);
          }
  
          if (graph.features().graph().supportsTransactions()) {
              graph.tx().commit();
          }
      }
  
      public void update(Graph graph, Long counter, String status) {
          migrationStatus.property(OPERATION_STATUS_PROPERTY, status);
  
          update(graph, counter, true);
      }
  
      public void clear() {
          migrationStatus = null;
      }
  
      public long getStartIndex() {
          return (long) migrationStatus.property(CURRENT_INDEX_PROPERTY).value();
      }
  
      private Vertex fetchUsingId(GraphTraversalSource g) {
          return g.V(migrationStatusId).next();
      }
  
      private static Vertex fetchUsingTypeName(GraphTraversalSource g) {
          GraphTraversal<Vertex, Vertex> src = g.V().has(Constants.ENTITY_TYPE_PROPERTY_KEY, MIGRATION_STATUS_TYPE_NAME);
  
          return src.hasNext() ? src.next() : null;
      }
  
      private void createAndCommit(Graph rGraph) {
          Vertex v         = rGraph.addVertex();
          long   longValue = 0L;
  
          v.property(Constants.ENTITY_TYPE_PROPERTY_KEY, MIGRATION_STATUS_TYPE_NAME);
          v.property(CURRENT_COUNTER_PROPERTY, longValue);
          v.property(CURRENT_INDEX_PROPERTY, longValue);
          v.property(TOTAL_COUNT_PROPERTY, longValue);
          v.property(OPERATION_STATUS_PROPERTY, STATUS_NOT_STARTED);
          v.property(START_TIME_PROPERTY, new Date());
          v.property(END_TIME_PROPERTY, new Date());
  
          migrationStatusId = v.id();
  
          if (rGraph.features().graph().supportsTransactions()) {
              rGraph.tx().commit();
          }
  
          LOG.info("migrationStatus vertex created! v[{}]", migrationStatusId);
      }
  
      private static void setValues(MigrationStatus ms, Vertex vertex) {
          ms.setStartTime((Date) vertex.property(START_TIME_PROPERTY).value());
          ms.setEndTime((Date) vertex.property(END_TIME_PROPERTY).value());
          ms.setCurrentIndex((Long) vertex.property(CURRENT_INDEX_PROPERTY).value());
          ms.setCurrentCounter((Long) vertex.property(CURRENT_COUNTER_PROPERTY).value());
          ms.setOperationStatus((String) vertex.property(OPERATION_STATUS_PROPERTY).value());
          ms.setTotalCount((Long) vertex.property(TOTAL_COUNT_PROPERTY).value());
      }
  }
  