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.mvcc;
  
  import com.google.common.annotations.VisibleForTesting;
  import io.netty.buffer.ByteBuf;
  import java.util.concurrent.CompletableFuture;
  import java.util.function.Supplier;
  import lombok.extern.slf4j.Slf4j;
  import org.apache.bookkeeper.api.kv.op.DeleteOp;
  import org.apache.bookkeeper.api.kv.op.IncrementOp;
  import org.apache.bookkeeper.api.kv.op.OpFactory;
  import org.apache.bookkeeper.api.kv.op.PutOp;
  import org.apache.bookkeeper.api.kv.op.RangeOp;
  import org.apache.bookkeeper.api.kv.op.TxnOp;
  import org.apache.bookkeeper.api.kv.result.DeleteResult;
  import org.apache.bookkeeper.api.kv.result.IncrementResult;
  import org.apache.bookkeeper.api.kv.result.PutResult;
  import org.apache.bookkeeper.api.kv.result.RangeResult;
  import org.apache.bookkeeper.api.kv.result.TxnResult;
  import org.apache.bookkeeper.common.concurrent.FutureUtils;
  import org.apache.bookkeeper.statelib.api.exceptions.InvalidStateStoreException;
  import org.apache.bookkeeper.statelib.api.mvcc.MVCCAsyncStore;
  import org.apache.bookkeeper.statelib.impl.journal.AbstractStateStoreWithJournal;
  import org.apache.bookkeeper.statelib.impl.journal.CommandProcessor;
  import org.apache.bookkeeper.stream.proto.kv.store.Command;
  import org.apache.distributedlog.api.namespace.Namespace;
  
  /**
   * MVCC Async Store Implementation.
   */
  @Slf4j
  class MVCCAsyncBytesStoreImpl
      extends AbstractStateStoreWithJournal<MVCCStoreImpl<byte[], byte[]>>
      implements MVCCAsyncStore<byte[], byte[]> {
  
      MVCCAsyncBytesStoreImpl(Supplier<MVCCStoreImpl<byte[], byte[]>> storeSupplier,
                              Supplier<Namespace> namespaceSupplier) {
          super(storeSupplier, namespaceSupplier);
      }
  
      @Override
      protected ByteBuf newCatchupMarker() {
          return MVCCUtils.newLogRecordBuf(MVCCUtils.NOP_CMD);
      }
  
      @Override
      protected CommandProcessor<MVCCStoreImpl<byte[], byte[]>> newCommandProcessor() {
          return MVCCCommandProcessor.of();
      }
  
      @VisibleForTesting
      @Override
      public boolean ownWriteScheduler() {
          return super.ownWriteScheduler();
      }
  
      @VisibleForTesting
      @Override
      public boolean ownReadScheduler() {
          return super.ownReadScheduler();
      }
  
      @Override
      public OpFactory<byte[], byte[]> getOpFactory() {
          return localStore.getOpFactory();
      }
  
      private CompletableFuture<Long> writeCommandReturnTxId(Command command) {
          ByteBuf recordBuf = MVCCUtils.newLogRecordBuf(command);
          return writeCommandBufReturnTxId(recordBuf);
      }
  
      @Override
      public CompletableFuture<RangeResult<byte[], byte[]>> range(RangeOp<byte[], byte[]> rangeOp) {
          synchronized (this) {
              if (!isInitialized) {
                  return FutureUtils.exception(new InvalidStateStoreException("State store is not initialized yet."));
              }
          }
  
          // consider running read operations in separate I/O threads
          return executeReadIO(() -> localStore.range(rangeOp));
      }
  
      @Override
      public CompletableFuture<PutResult<byte[], byte[]>> put(PutOp<byte[], byte[]> op) {
          synchronized (this) {
              if (!isInitialized) {
                  return FutureUtils.exception(new InvalidStateStoreException("State store is not initialized yet."));
              }
          }
  
          Command command = MVCCUtils.toCommand(op);
          return writeCommandReturnTxId(command)
              .thenApplyAsync(revision -> localStore.put(revision, op), writeIOScheduler);
      }
  
      @Override
      public CompletableFuture<DeleteResult<byte[], byte[]>> delete(DeleteOp<byte[], byte[]> op) {
          synchronized (this) {
              if (!isInitialized) {
                  return FutureUtils.exception(new InvalidStateStoreException("State store is not initialized yet."));
              }
          }
  
          Command command = MVCCUtils.toCommand(op);
          return writeCommandReturnTxId(command)
              .thenApplyAsync(revision -> localStore.delete(revision, op), writeIOScheduler);
      }
  
      @Override
      public CompletableFuture<TxnResult<byte[], byte[]>> txn(TxnOp<byte[], byte[]> op) {
          synchronized (this) {
              if (!isInitialized) {
                  return FutureUtils.exception(new InvalidStateStoreException("State store is not initialized yet."));
              }
          }
  
          Command command = MVCCUtils.toCommand(op);
          return writeCommandReturnTxId(command)
              .thenApplyAsync(revision -> localStore.txn(revision, op), writeIOScheduler);
      }
  
      @Override
      public CompletableFuture<IncrementResult<byte[], byte[]>> increment(IncrementOp<byte[], byte[]> op) {
          synchronized (this) {
              if (!isInitialized) {
                  return FutureUtils.exception(new InvalidStateStoreException("State store is not initialized yet."));
              }
          }
          Command command = MVCCUtils.toCommand(op);
          return writeCommandReturnTxId(command)
              .thenApplyAsync(revision -> localStore.increment(revision, op), writeIOScheduler);
      }
  }
  