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.bookie.storage.ldb;
  
  import static org.apache.bookkeeper.util.BookKeeperConstants.METADATA_CACHE;
  
  import io.netty.util.concurrent.FastThreadLocal;
  import java.io.ByteArrayInputStream;
  import java.io.ByteArrayOutputStream;
  import java.io.DataInputStream;
  import java.io.DataOutputStream;
  import java.io.File;
  import java.io.IOException;
  import java.util.Map.Entry;
  import java.util.concurrent.atomic.AtomicBoolean;
  import java.util.function.BiConsumer;
  import lombok.extern.slf4j.Slf4j;
  import org.apache.bookkeeper.bookie.BookieException.EntryLogMetadataMapException;
  import org.apache.bookkeeper.bookie.EntryLogMetadata;
  import org.apache.bookkeeper.bookie.EntryLogMetadata.EntryLogMetadataRecyclable;
  import org.apache.bookkeeper.bookie.EntryLogMetadataMap;
  import org.apache.bookkeeper.bookie.storage.ldb.KeyValueStorage.CloseableIterator;
  import org.apache.bookkeeper.bookie.storage.ldb.KeyValueStorageFactory.DbConfigType;
  import org.apache.bookkeeper.conf.ServerConfiguration;
  
  /**
   * Persistent entryLogMetadata-map that stores entry-loggers metadata into
   * rocksDB.
   */
  @Slf4j
  public class PersistentEntryLogMetadataMap implements EntryLogMetadataMap {
      // persistent Rocksdb to store metadata-map
      private final KeyValueStorage metadataMapDB;
      private AtomicBoolean isClosed = new AtomicBoolean(false);
  
      private static final FastThreadLocal<ByteArrayOutputStream> baos = new FastThreadLocal<ByteArrayOutputStream>() {
          @Override
          protected ByteArrayOutputStream initialValue() {
              return new ByteArrayOutputStream();
          }
      };
      private static final FastThreadLocal<ByteArrayInputStream> bais = new FastThreadLocal<ByteArrayInputStream>() {
          @Override
          protected ByteArrayInputStream initialValue() {
              return new ByteArrayInputStream(new byte[1]);
          }
      };
      private static final FastThreadLocal<DataOutputStream> dataos = new FastThreadLocal<DataOutputStream>() {
          @Override
          protected DataOutputStream initialValue() {
              return new DataOutputStream(baos.get());
          }
      };
      private static final FastThreadLocal<DataInputStream> datais = new FastThreadLocal<DataInputStream>() {
          @Override
          protected DataInputStream initialValue() {
              return new DataInputStream(bais.get());
          }
      };
  
      public PersistentEntryLogMetadataMap(String metadataPath, ServerConfiguration conf) throws IOException {
          log.info("Loading persistent entrylog metadata-map from {}/{}", metadataPath, METADATA_CACHE);
          File dir = new File(metadataPath);
          if (!dir.mkdirs() && !dir.exists()) {
              String err = "Unable to create directory " + dir;
              log.error(err);
              throw new IOException(err);
          }
          metadataMapDB = KeyValueStorageRocksDB.factory.newKeyValueStorage(metadataPath, METADATA_CACHE,
                  DbConfigType.Default, conf);
      }
  
      @Override
      public boolean containsKey(long entryLogId) throws EntryLogMetadataMapException {
          throwIfClosed();
          LongWrapper key = LongWrapper.get(entryLogId);
          try {
              boolean isExist;
              try {
                  isExist = metadataMapDB.get(key.array) != null;
              } catch (IOException e) {
                  throw new EntryLogMetadataMapException(e);
              }
              return isExist;
          } finally {
              key.recycle();
          }
      }
  
      @Override
      public void put(long entryLogId, EntryLogMetadata entryLogMeta) throws EntryLogMetadataMapException {
          throwIfClosed();
          LongWrapper key = LongWrapper.get(entryLogId);
          try {
              baos.get().reset();
              try {
                  entryLogMeta.serialize(dataos.get());
                  metadataMapDB.put(key.array, baos.get().toByteArray());
              } catch (IllegalStateException | IOException e) {
                  log.error("Failed to serialize entrylog-metadata, entryLogId {}", entryLogId);
                  throw new EntryLogMetadataMapException(e);
              }
          } finally {
              key.recycle();
          }
  
      }
  
      /**
       * {@link EntryLogMetadata} life-cycle in supplied action will be transient
       * and it will be recycled as soon as supplied action is completed.
       */
      @Override
      public void forEach(BiConsumer<Long, EntryLogMetadata> action) throws EntryLogMetadataMapException {
          throwIfClosed();
          CloseableIterator<Entry<byte[], byte[]>> iterator = metadataMapDB.iterator();
          try {
              while (iterator.hasNext()) {
                  if (isClosed.get()) {
                      break;
                  }
                  Entry<byte[], byte[]> entry = iterator.next();
                  long entryLogId = ArrayUtil.getLong(entry.getKey(), 0);
                  EntryLogMetadataRecyclable metadata = getEntryLogMetadataRecyclable(entry.getValue());
                  try {
                      action.accept(entryLogId, metadata);
                  } finally {
                      metadata.recycle();
                  }
              }
          } catch (IOException e) {
              log.error("Failed to iterate over entry-log metadata map {}", e.getMessage(), e);
              throw new EntryLogMetadataMapException(e);
          } finally {
              try {
                  iterator.close();
              } catch (IOException e) {
                  log.error("Failed to close entry-log metadata-map rocksDB iterator {}", e.getMessage(), e);
              }
          }
      }
  
      /**
       * {@link EntryLogMetadata} life-cycle in supplied action will be transient
       * and it will be recycled as soon as supplied action is completed.
       */
      @Override
      public void forKey(long entryLogId, BiConsumer<Long, EntryLogMetadata> action) throws EntryLogMetadataMapException {
          throwIfClosed();
          LongWrapper key = LongWrapper.get(entryLogId);
          try {
              byte[] value = metadataMapDB.get(key.array);
              if (value == null || value.length == 0) {
                  action.accept(entryLogId, null);
                  return;
              }
              EntryLogMetadataRecyclable metadata = getEntryLogMetadataRecyclable(value);
              try {
                  action.accept(entryLogId, metadata);
              } finally {
                  metadata.recycle();
              }
          } catch (IOException e) {
              log.error("Failed to get metadata for entryLogId {}: {}", entryLogId, e.getMessage(), e);
              throw new EntryLogMetadataMapException(e);
          } finally {
              key.recycle();
          }
      }
  
      private EntryLogMetadataRecyclable getEntryLogMetadataRecyclable(byte[] value) throws IOException {
          ByteArrayInputStream localBais = bais.get();
          DataInputStream localDatais = datais.get();
          if (localBais.available() < value.length) {
              localBais.close();
              localDatais.close();
              ByteArrayInputStream newBais = new ByteArrayInputStream(value);
              bais.set(newBais);
              datais.set(new DataInputStream(newBais));
          } else {
              localBais.read(value, 0, value.length);
          }
          localBais.reset();
          localDatais.reset();
          EntryLogMetadataRecyclable metadata = EntryLogMetadata.deserialize(datais.get());
          return metadata;
      }
  
      @Override
      public void remove(long entryLogId) throws EntryLogMetadataMapException {
          throwIfClosed();
          LongWrapper key = LongWrapper.get(entryLogId);
          try {
              try {
                  metadataMapDB.delete(key.array);
              } catch (IOException e) {
                  throw new EntryLogMetadataMapException(e);
              }
          } finally {
              key.recycle();
          }
      }
  
      @Override
      public int size() throws EntryLogMetadataMapException {
          throwIfClosed();
          try {
              return (int) metadataMapDB.count();
          } catch (IOException e) {
              throw new EntryLogMetadataMapException(e);
          }
      }
  
      @Override
      public void clear() throws EntryLogMetadataMapException {
          try {
              try (KeyValueStorage.Batch b = metadataMapDB.newBatch();
                   CloseableIterator<byte[]> itr = metadataMapDB.keys()) {
                  while (itr.hasNext()) {
                      b.remove(itr.next());
                  }
                  b.flush();
              }
          } catch (IOException e) {
              throw new EntryLogMetadataMapException(e);
          }
      }
  
      @Override
      public void close() throws IOException {
          if (isClosed.compareAndSet(false, true)) {
              metadataMapDB.close();
          } else {
              log.warn("Attempted to close already closed PersistentEntryLogMetadataMap");
          }
      }
  
      public void throwIfClosed() throws EntryLogMetadataMapException {
          if (isClosed.get()) {
              final String msg = "Attempted to use PersistentEntryLogMetadataMap after it was closed";
              log.error(msg);
              throw new EntryLogMetadataMapException(new IOException(msg));
          }
      }
  }
  