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
   *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * 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.bookkeeper.statelib.impl.rocksdb.checkpoint;
  
  import com.google.common.io.MoreFiles;
  import com.google.common.io.RecursiveDeleteOption;
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.nio.file.Paths;
  import java.time.Duration;
  import java.util.UUID;
  import java.util.concurrent.TimeoutException;
  import lombok.extern.slf4j.Slf4j;
  import org.apache.bookkeeper.statelib.api.checkpoint.CheckpointStore;
  import org.apache.bookkeeper.statelib.api.exceptions.StateStoreException;
  import org.apache.bookkeeper.stream.proto.kv.store.CheckpointMetadata;
  
  
  /**
   * CheckpointInfo encapsulated information and operation for a checkpoint.
   */
  @Slf4j
  public class CheckpointInfo implements Comparable<CheckpointInfo> {
  
      final String id;
      CheckpointMetadata metadata;
  
      public CheckpointInfo(String id, InputStream is) throws IOException {
          this.id = id;
          this.metadata = CheckpointMetadata.parseFrom(is);
      }
  
      public CheckpointInfo(String id) {
          this.id = id;
      }
      public String getId() {
          return id;
      }
  
      public CheckpointMetadata getMetadata() {
          return metadata;
      }
  
      @Override
      public String toString() {
          return "Checkpoint{ID='" + id + "', createdAt: " + getCreatedAt() + " " + metadata + "}";
      }
  
      // default fallback checkpoint. This essentially creates a blank store.
      public static CheckpointInfo nullCheckpoint() {
          return new CheckpointInfo(UUID.randomUUID().toString()) {
              public CheckpointMetadata restore(String dbName,
                                                File dbPath,
                                                CheckpointStore store,
                                                Duration maxIdle) throws StateStoreException {
                  try {
                      Files.createDirectories(getCheckpointPath(dbPath));
                      updateCurrent(dbPath);
                  } catch (IOException ioe) {
                      throw new StateStoreException("Failed to create dir " + dbName, ioe);
                  }
                  return null;
              }
              // for proper sorting
              public Long getCreatedAt() {
                  return 0L;
              }
          };
      }
  
      public void remove(File dbPath) {
          try {
              Path checkpointPath = getCheckpointPath(dbPath);
              if (checkpointPath.toFile().exists()) {
                  MoreFiles.deleteRecursively(checkpointPath, RecursiveDeleteOption.ALLOW_INSECURE);
              }
          } catch (IOException ioe) {
              log.warn("Failed to remove unused checkpoint {} from {}",
                  id, getCheckpointBaseDir(dbPath), ioe);
          }
      }
  
      public Long getCreatedAt() {
          return this.metadata.getCreatedAt();
      }
  
      public File getCheckpointBaseDir(File dbPath) {
          return new File(dbPath, "checkpoints");
      }
  
      public Path getCheckpointPath(File dbPath) {
          return Paths.get(getCheckpointBaseDir(dbPath).getAbsolutePath(), id);
      }
  
      public File getCurrentDir(File dbPath) {
          return new File(dbPath, "current");
      }
      public Path getCurrentPath(File dbPath) {
          return Paths.get(getCurrentDir(dbPath).getAbsolutePath());
      }
  
      public void updateCurrent(File dbPath) throws IOException {
          Path currentPath = getCurrentPath(dbPath);
          Files.deleteIfExists(currentPath);
          Files.createSymbolicLink(currentPath, getCheckpointPath(dbPath));
      }
  
      @Override
      public int compareTo(CheckpointInfo o) {
          return this.getCreatedAt().compareTo(o.getCreatedAt());
      }
  
      public CheckpointMetadata restore(File dbPath, RocksdbRestoreTask task)
          throws StateStoreException, IOException, TimeoutException {
  
          task.restore(id, metadata);
          updateCurrent(dbPath);
          log.info("Successfully restore checkpoint {} to {}", id, getCheckpointPath(dbPath));
          return metadata;
      }
      public CheckpointMetadata restore(String dbName, File dbPath, CheckpointStore store)
          throws StateStoreException, TimeoutException {
  
          return restore(dbName, dbPath, store, Duration.ofMinutes(1));
      }
  
      public CheckpointMetadata restore(String dbName, File dbPath, CheckpointStore store, Duration maxIdle)
          throws StateStoreException, TimeoutException {
  
          try {
              File checkpointsDir = new File(dbPath, "checkpoints");
              RocksdbRestoreTask task = new RocksdbRestoreTask(dbName, checkpointsDir, store, maxIdle);
              return restore(dbPath, task);
          } catch (IOException ioe) {
              log.error("Failed to restore rocksdb {}", dbName, ioe);
              throw new StateStoreException("Failed to restore rocksdb " + dbName, ioe);
          }
      }
  }
  