soft_bus/rocksdb/db/blob/db_blob_basic_test.cc

//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
//  This source code is licensed under both the GPLv2 (found in the
//  COPYING file in the root directory) and Apache 2.0 License
//  (found in the LICENSE.Apache file in the root directory).

#include <array>
#include <sstream>
#include <string>

#include "cache/compressed_secondary_cache.h"
#include "db/blob/blob_index.h"
#include "db/blob/blob_log_format.h"
#include "db/db_test_util.h"
#include "db/db_with_timestamp_test_util.h"
#include "port/stack_trace.h"
#include "test_util/sync_point.h"
#include "utilities/fault_injection_env.h"

namespace ROCKSDB_NAMESPACE {

class DBBlobBasicTest : public DBTestBase {
 protected:
  DBBlobBasicTest()
      : DBTestBase("db_blob_basic_test", /* env_do_fsync */ false) {}
};

TEST_F(DBBlobBasicTest, GetBlob) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  constexpr char key[] = "key";
  constexpr char blob_value[] = "blob_value";

  ASSERT_OK(Put(key, blob_value));

  ASSERT_OK(Flush());

  ASSERT_EQ(Get(key), blob_value);

  // Try again with no I/O allowed. The table and the necessary blocks should
  // already be in their respective caches; however, the blob itself can only be
  // read from the blob file, so the read should return Incomplete.
  ReadOptions read_options;
  read_options.read_tier = kBlockCacheTier;

  PinnableSlice result;
  ASSERT_TRUE(db_->Get(read_options, db_->DefaultColumnFamily(), key, &result)
                  .IsIncomplete());
}

TEST_F(DBBlobBasicTest, GetBlobFromCache) {
  Options options = GetDefaultOptions();

  LRUCacheOptions co;
  co.capacity = 2 << 20;  // 2MB
  co.num_shard_bits = 2;
  co.metadata_charge_policy = kDontChargeCacheMetadata;
  auto backing_cache = NewLRUCache(co);

  options.enable_blob_files = true;
  options.blob_cache = backing_cache;

  BlockBasedTableOptions block_based_options;
  block_based_options.no_block_cache = false;
  block_based_options.block_cache = backing_cache;
  block_based_options.cache_index_and_filter_blocks = true;
  options.table_factory.reset(NewBlockBasedTableFactory(block_based_options));

  Reopen(options);

  constexpr char key[] = "key";
  constexpr char blob_value[] = "blob_value";

  ASSERT_OK(Put(key, blob_value));

  ASSERT_OK(Flush());

  ReadOptions read_options;

  read_options.fill_cache = false;

  {
    PinnableSlice result;

    read_options.read_tier = kReadAllTier;
    ASSERT_OK(db_->Get(read_options, db_->DefaultColumnFamily(), key, &result));
    ASSERT_EQ(result, blob_value);

    result.Reset();
    read_options.read_tier = kBlockCacheTier;

    // Try again with no I/O allowed. Since we didn't re-fill the cache, the
    // blob itself can only be read from the blob file, so the read should
    // return Incomplete.
    ASSERT_TRUE(db_->Get(read_options, db_->DefaultColumnFamily(), key, &result)
                    .IsIncomplete());
    ASSERT_TRUE(result.empty());
  }

  read_options.fill_cache = true;

  {
    PinnableSlice result;

    read_options.read_tier = kReadAllTier;
    ASSERT_OK(db_->Get(read_options, db_->DefaultColumnFamily(), key, &result));
    ASSERT_EQ(result, blob_value);

    result.Reset();
    read_options.read_tier = kBlockCacheTier;

    // Try again with no I/O allowed. The table and the necessary blocks/blobs
    // should already be in their respective caches.
    ASSERT_OK(db_->Get(read_options, db_->DefaultColumnFamily(), key, &result));
    ASSERT_EQ(result, blob_value);
  }
}

TEST_F(DBBlobBasicTest, IterateBlobsFromCache) {
  Options options = GetDefaultOptions();

  LRUCacheOptions co;
  co.capacity = 2 << 20;  // 2MB
  co.num_shard_bits = 2;
  co.metadata_charge_policy = kDontChargeCacheMetadata;
  auto backing_cache = NewLRUCache(co);

  options.enable_blob_files = true;
  options.blob_cache = backing_cache;

  BlockBasedTableOptions block_based_options;
  block_based_options.no_block_cache = false;
  block_based_options.block_cache = backing_cache;
  block_based_options.cache_index_and_filter_blocks = true;
  options.table_factory.reset(NewBlockBasedTableFactory(block_based_options));

  options.statistics = CreateDBStatistics();

  Reopen(options);

  int num_blobs = 5;
  std::vector<std::string> keys;
  std::vector<std::string> blobs;

  for (int i = 0; i < num_blobs; ++i) {
    keys.push_back("key" + std::to_string(i));
    blobs.push_back("blob" + std::to_string(i));
    ASSERT_OK(Put(keys[i], blobs[i]));
  }
  ASSERT_OK(Flush());

  ReadOptions read_options;

  {
    read_options.fill_cache = false;
    read_options.read_tier = kReadAllTier;

    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    int i = 0;
    for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
      ASSERT_OK(iter->status());
      ASSERT_EQ(iter->key().ToString(), keys[i]);
      ASSERT_EQ(iter->value().ToString(), blobs[i]);
      ++i;
    }
    ASSERT_OK(iter->status());
    ASSERT_EQ(i, num_blobs);
    ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_ADD), 0);
  }

  {
    read_options.fill_cache = false;
    read_options.read_tier = kBlockCacheTier;

    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    // Try again with no I/O allowed. Since we didn't re-fill the cache,
    // the blob itself can only be read from the blob file, so iter->Valid()
    // should be false.
    iter->SeekToFirst();
    ASSERT_NOK(iter->status());
    ASSERT_FALSE(iter->Valid());
    ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_ADD), 0);
  }

  {
    read_options.fill_cache = true;
    read_options.read_tier = kReadAllTier;

    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    // Read blobs from the file and refill the cache.
    int i = 0;
    for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
      ASSERT_OK(iter->status());
      ASSERT_EQ(iter->key().ToString(), keys[i]);
      ASSERT_EQ(iter->value().ToString(), blobs[i]);
      ++i;
    }
    ASSERT_OK(iter->status());
    ASSERT_EQ(i, num_blobs);
    ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_ADD),
              num_blobs);
  }

  {
    read_options.fill_cache = false;
    read_options.read_tier = kBlockCacheTier;

    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    // Try again with no I/O allowed. The table and the necessary blocks/blobs
    // should already be in their respective caches.
    int i = 0;
    for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
      ASSERT_OK(iter->status());
      ASSERT_EQ(iter->key().ToString(), keys[i]);
      ASSERT_EQ(iter->value().ToString(), blobs[i]);
      ++i;
    }
    ASSERT_OK(iter->status());
    ASSERT_EQ(i, num_blobs);
    ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_ADD), 0);
  }
}

TEST_F(DBBlobBasicTest, IterateBlobsFromCachePinning) {
  constexpr size_t min_blob_size = 6;

  Options options = GetDefaultOptions();

  LRUCacheOptions cache_options;
  cache_options.capacity = 2048;
  cache_options.num_shard_bits = 0;
  cache_options.metadata_charge_policy = kDontChargeCacheMetadata;

  options.blob_cache = NewLRUCache(cache_options);
  options.enable_blob_files = true;
  options.min_blob_size = min_blob_size;

  Reopen(options);

  // Put then iterate over three key-values. The second value is below the size
  // limit and is thus stored inline; the other two are stored separately as
  // blobs. We expect to have something pinned in the cache iff we are
  // positioned on a blob.

  constexpr char first_key[] = "first_key";
  constexpr char first_value[] = "long_value";
  static_assert(sizeof(first_value) - 1 >= min_blob_size,
                "first_value too short to be stored as blob");

  ASSERT_OK(Put(first_key, first_value));

  constexpr char second_key[] = "second_key";
  constexpr char second_value[] = "short";
  static_assert(sizeof(second_value) - 1 < min_blob_size,
                "second_value too long to be inlined");

  ASSERT_OK(Put(second_key, second_value));

  constexpr char third_key[] = "third_key";
  constexpr char third_value[] = "other_long_value";
  static_assert(sizeof(third_value) - 1 >= min_blob_size,
                "third_value too short to be stored as blob");

  ASSERT_OK(Put(third_key, third_value));

  ASSERT_OK(Flush());

  {
    ReadOptions read_options;
    read_options.fill_cache = true;

    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));

    iter->SeekToFirst();
    ASSERT_TRUE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(iter->key(), first_key);
    ASSERT_EQ(iter->value(), first_value);

    iter->Next();
    ASSERT_TRUE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(iter->key(), second_key);
    ASSERT_EQ(iter->value(), second_value);

    iter->Next();
    ASSERT_TRUE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(iter->key(), third_key);
    ASSERT_EQ(iter->value(), third_value);

    iter->Next();
    ASSERT_FALSE(iter->Valid());
    ASSERT_OK(iter->status());
  }

  {
    ReadOptions read_options;
    read_options.fill_cache = false;
    read_options.read_tier = kBlockCacheTier;

    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));

    iter->SeekToFirst();
    ASSERT_TRUE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(iter->key(), first_key);
    ASSERT_EQ(iter->value(), first_value);
    ASSERT_GT(options.blob_cache->GetPinnedUsage(), 0);

    iter->Next();
    ASSERT_TRUE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(iter->key(), second_key);
    ASSERT_EQ(iter->value(), second_value);
    ASSERT_EQ(options.blob_cache->GetPinnedUsage(), 0);

    iter->Next();
    ASSERT_TRUE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(iter->key(), third_key);
    ASSERT_EQ(iter->value(), third_value);
    ASSERT_GT(options.blob_cache->GetPinnedUsage(), 0);

    iter->Next();
    ASSERT_FALSE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(options.blob_cache->GetPinnedUsage(), 0);
  }

  {
    ReadOptions read_options;
    read_options.fill_cache = false;
    read_options.read_tier = kBlockCacheTier;

    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));

    iter->SeekToLast();
    ASSERT_TRUE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(iter->key(), third_key);
    ASSERT_EQ(iter->value(), third_value);
    ASSERT_GT(options.blob_cache->GetPinnedUsage(), 0);

    iter->Prev();
    ASSERT_TRUE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(iter->key(), second_key);
    ASSERT_EQ(iter->value(), second_value);
    ASSERT_EQ(options.blob_cache->GetPinnedUsage(), 0);

    iter->Prev();
    ASSERT_TRUE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(iter->key(), first_key);
    ASSERT_EQ(iter->value(), first_value);
    ASSERT_GT(options.blob_cache->GetPinnedUsage(), 0);

    iter->Prev();
    ASSERT_FALSE(iter->Valid());
    ASSERT_OK(iter->status());
    ASSERT_EQ(options.blob_cache->GetPinnedUsage(), 0);
  }
}

TEST_F(DBBlobBasicTest, IterateBlobsAllowUnpreparedValue) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;

  Reopen(options);

  constexpr size_t num_blobs = 5;
  std::vector<std::string> keys;
  std::vector<std::string> blobs;

  for (size_t i = 0; i < num_blobs; ++i) {
    keys.emplace_back("key" + std::to_string(i));
    blobs.emplace_back("blob" + std::to_string(i));
    ASSERT_OK(Put(keys[i], blobs[i]));
  }

  ASSERT_OK(Flush());

  ReadOptions read_options;
  read_options.allow_unprepared_value = true;

  std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));

  {
    size_t i = 0;

    for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
      ASSERT_EQ(iter->key(), keys[i]);
      ASSERT_TRUE(iter->value().empty());
      ASSERT_OK(iter->status());

      ASSERT_TRUE(iter->PrepareValue());

      ASSERT_EQ(iter->key(), keys[i]);
      ASSERT_EQ(iter->value(), blobs[i]);
      ASSERT_OK(iter->status());

      ++i;
    }

    ASSERT_OK(iter->status());
    ASSERT_EQ(i, num_blobs);
  }

  {
    size_t i = 0;

    for (iter->SeekToLast(); iter->Valid(); iter->Prev()) {
      ASSERT_EQ(iter->key(), keys[num_blobs - 1 - i]);
      ASSERT_TRUE(iter->value().empty());
      ASSERT_OK(iter->status());

      ASSERT_TRUE(iter->PrepareValue());

      ASSERT_EQ(iter->key(), keys[num_blobs - 1 - i]);
      ASSERT_EQ(iter->value(), blobs[num_blobs - 1 - i]);
      ASSERT_OK(iter->status());

      ++i;
    }

    ASSERT_OK(iter->status());
    ASSERT_EQ(i, num_blobs);
  }

  {
    size_t i = 1;

    for (iter->Seek(keys[i]); iter->Valid(); iter->Next()) {
      ASSERT_EQ(iter->key(), keys[i]);
      ASSERT_TRUE(iter->value().empty());
      ASSERT_OK(iter->status());

      ASSERT_TRUE(iter->PrepareValue());

      ASSERT_EQ(iter->key(), keys[i]);
      ASSERT_EQ(iter->value(), blobs[i]);
      ASSERT_OK(iter->status());

      ++i;
    }

    ASSERT_OK(iter->status());
    ASSERT_EQ(i, num_blobs);
  }

  {
    size_t i = 1;

    for (iter->SeekForPrev(keys[num_blobs - 1 - i]); iter->Valid();
         iter->Prev()) {
      ASSERT_EQ(iter->key(), keys[num_blobs - 1 - i]);
      ASSERT_TRUE(iter->value().empty());
      ASSERT_OK(iter->status());

      ASSERT_TRUE(iter->PrepareValue());

      ASSERT_EQ(iter->key(), keys[num_blobs - 1 - i]);
      ASSERT_EQ(iter->value(), blobs[num_blobs - 1 - i]);
      ASSERT_OK(iter->status());

      ++i;
    }

    ASSERT_OK(iter->status());
    ASSERT_EQ(i, num_blobs);
  }
}

TEST_F(DBBlobBasicTest, MultiGetBlobs) {
  constexpr size_t min_blob_size = 6;

  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = min_blob_size;

  Reopen(options);

  // Put then retrieve three key-values. The first value is below the size limit
  // and is thus stored inline; the other two are stored separately as blobs.
  constexpr size_t num_keys = 3;

  constexpr char first_key[] = "first_key";
  constexpr char first_value[] = "short";
  static_assert(sizeof(first_value) - 1 < min_blob_size,
                "first_value too long to be inlined");

  ASSERT_OK(Put(first_key, first_value));

  constexpr char second_key[] = "second_key";
  constexpr char second_value[] = "long_value";
  static_assert(sizeof(second_value) - 1 >= min_blob_size,
                "second_value too short to be stored as blob");

  ASSERT_OK(Put(second_key, second_value));

  constexpr char third_key[] = "third_key";
  constexpr char third_value[] = "other_long_value";
  static_assert(sizeof(third_value) - 1 >= min_blob_size,
                "third_value too short to be stored as blob");

  ASSERT_OK(Put(third_key, third_value));

  ASSERT_OK(Flush());

  ReadOptions read_options;

  std::array<Slice, num_keys> keys{{first_key, second_key, third_key}};

  {
    std::array<PinnableSlice, num_keys> values;
    std::array<Status, num_keys> statuses;

    db_->MultiGet(read_options, db_->DefaultColumnFamily(), num_keys,
                  keys.data(), values.data(), statuses.data());

    ASSERT_OK(statuses[0]);
    ASSERT_EQ(values[0], first_value);

    ASSERT_OK(statuses[1]);
    ASSERT_EQ(values[1], second_value);

    ASSERT_OK(statuses[2]);
    ASSERT_EQ(values[2], third_value);
  }

  // Try again with no I/O allowed. The table and the necessary blocks should
  // already be in their respective caches. The first (inlined) value should be
  // successfully read; however, the two blob values could only be read from the
  // blob file, so for those the read should return Incomplete.
  read_options.read_tier = kBlockCacheTier;

  {
    std::array<PinnableSlice, num_keys> values;
    std::array<Status, num_keys> statuses;

    db_->MultiGet(read_options, db_->DefaultColumnFamily(), num_keys,
                  keys.data(), values.data(), statuses.data());

    ASSERT_OK(statuses[0]);
    ASSERT_EQ(values[0], first_value);

    ASSERT_TRUE(statuses[1].IsIncomplete());

    ASSERT_TRUE(statuses[2].IsIncomplete());
  }
}

TEST_F(DBBlobBasicTest, MultiGetBlobsFromCache) {
  Options options = GetDefaultOptions();

  LRUCacheOptions co;
  co.capacity = 2 << 20;  // 2MB
  co.num_shard_bits = 2;
  co.metadata_charge_policy = kDontChargeCacheMetadata;
  auto backing_cache = NewLRUCache(co);

  constexpr size_t min_blob_size = 6;
  options.min_blob_size = min_blob_size;
  options.create_if_missing = true;
  options.enable_blob_files = true;
  options.blob_cache = backing_cache;

  BlockBasedTableOptions block_based_options;
  block_based_options.no_block_cache = false;
  block_based_options.block_cache = backing_cache;
  block_based_options.cache_index_and_filter_blocks = true;
  options.table_factory.reset(NewBlockBasedTableFactory(block_based_options));

  DestroyAndReopen(options);

  // Put then retrieve three key-values. The first value is below the size limit
  // and is thus stored inline; the other two are stored separately as blobs.
  constexpr size_t num_keys = 3;

  constexpr char first_key[] = "first_key";
  constexpr char first_value[] = "short";
  static_assert(sizeof(first_value) - 1 < min_blob_size,
                "first_value too long to be inlined");

  ASSERT_OK(Put(first_key, first_value));

  constexpr char second_key[] = "second_key";
  constexpr char second_value[] = "long_value";
  static_assert(sizeof(second_value) - 1 >= min_blob_size,
                "second_value too short to be stored as blob");

  ASSERT_OK(Put(second_key, second_value));

  constexpr char third_key[] = "third_key";
  constexpr char third_value[] = "other_long_value";
  static_assert(sizeof(third_value) - 1 >= min_blob_size,
                "third_value too short to be stored as blob");

  ASSERT_OK(Put(third_key, third_value));

  ASSERT_OK(Flush());

  ReadOptions read_options;
  read_options.fill_cache = false;

  std::array<Slice, num_keys> keys{{first_key, second_key, third_key}};

  {
    std::array<PinnableSlice, num_keys> values;
    std::array<Status, num_keys> statuses;

    db_->MultiGet(read_options, db_->DefaultColumnFamily(), num_keys,
                  keys.data(), values.data(), statuses.data());

    ASSERT_OK(statuses[0]);
    ASSERT_EQ(values[0], first_value);

    ASSERT_OK(statuses[1]);
    ASSERT_EQ(values[1], second_value);

    ASSERT_OK(statuses[2]);
    ASSERT_EQ(values[2], third_value);
  }

  // Try again with no I/O allowed. The first (inlined) value should be
  // successfully read; however, the two blob values could only be read from the
  // blob file, so for those the read should return Incomplete.
  read_options.read_tier = kBlockCacheTier;

  {
    std::array<PinnableSlice, num_keys> values;
    std::array<Status, num_keys> statuses;

    db_->MultiGet(read_options, db_->DefaultColumnFamily(), num_keys,
                  keys.data(), values.data(), statuses.data());

    ASSERT_OK(statuses[0]);
    ASSERT_EQ(values[0], first_value);

    ASSERT_TRUE(statuses[1].IsIncomplete());

    ASSERT_TRUE(statuses[2].IsIncomplete());
  }

  // Fill the cache when reading blobs from the blob file.
  read_options.read_tier = kReadAllTier;
  read_options.fill_cache = true;

  {
    std::array<PinnableSlice, num_keys> values;
    std::array<Status, num_keys> statuses;

    db_->MultiGet(read_options, db_->DefaultColumnFamily(), num_keys,
                  keys.data(), values.data(), statuses.data());

    ASSERT_OK(statuses[0]);
    ASSERT_EQ(values[0], first_value);

    ASSERT_OK(statuses[1]);
    ASSERT_EQ(values[1], second_value);

    ASSERT_OK(statuses[2]);
    ASSERT_EQ(values[2], third_value);
  }

  // Try again with no I/O allowed. All blobs should be successfully read from
  // the cache.
  read_options.read_tier = kBlockCacheTier;

  {
    std::array<PinnableSlice, num_keys> values;
    std::array<Status, num_keys> statuses;

    db_->MultiGet(read_options, db_->DefaultColumnFamily(), num_keys,
                  keys.data(), values.data(), statuses.data());

    ASSERT_OK(statuses[0]);
    ASSERT_EQ(values[0], first_value);

    ASSERT_OK(statuses[1]);
    ASSERT_EQ(values[1], second_value);

    ASSERT_OK(statuses[2]);
    ASSERT_EQ(values[2], third_value);
  }
}

TEST_F(DBBlobBasicTest, MultiGetWithDirectIO) {
  Options options = GetDefaultOptions();

  // First, create an external SST file ["b"].
  const std::string file_path = dbname_ + "/test.sst";
  {
    SstFileWriter sst_file_writer(EnvOptions(), GetDefaultOptions());
    Status s = sst_file_writer.Open(file_path);
    ASSERT_OK(s);
    ASSERT_OK(sst_file_writer.Put("b", "b_value"));
    ASSERT_OK(sst_file_writer.Finish());
  }

  options.enable_blob_files = true;
  options.min_blob_size = 1000;
  options.use_direct_reads = true;
  options.allow_ingest_behind = true;

  // Open DB with fixed-prefix sst-partitioner so that compaction will cut
  // new table file when encountering a new key whose 1-byte prefix changes.
  constexpr size_t key_len = 1;
  options.sst_partitioner_factory =
      NewSstPartitionerFixedPrefixFactory(key_len);

  Status s = TryReopen(options);
  if (s.IsInvalidArgument()) {
    ROCKSDB_GTEST_SKIP("This test requires direct IO support");
    return;
  }
  ASSERT_OK(s);

  constexpr size_t num_keys = 3;
  constexpr size_t blob_size = 3000;

  constexpr char first_key[] = "a";
  const std::string first_blob(blob_size, 'a');
  ASSERT_OK(Put(first_key, first_blob));

  constexpr char second_key[] = "b";
  const std::string second_blob(2 * blob_size, 'b');
  ASSERT_OK(Put(second_key, second_blob));

  constexpr char third_key[] = "d";
  const std::string third_blob(blob_size, 'd');
  ASSERT_OK(Put(third_key, third_blob));

  // first_blob, second_blob and third_blob in the same blob file.
  //      SST                    Blob file
  // L0  ["a",    "b",    "d"]   |'aaaa', 'bbbb', 'dddd'|
  //       |       |       |         ^       ^        ^
  //       |       |       |         |       |        |
  //       |       |       +---------|-------|--------+
  //       |       +-----------------|-------+
  //       +-------------------------+
  ASSERT_OK(Flush());

  constexpr char fourth_key[] = "c";
  const std::string fourth_blob(blob_size, 'c');
  ASSERT_OK(Put(fourth_key, fourth_blob));
  // fourth_blob in another blob file.
  //      SST                    Blob file                 SST     Blob file
  // L0  ["a",    "b",    "d"]   |'aaaa', 'bbbb', 'dddd'|  ["c"]   |'cccc'|
  //       |       |       |         ^       ^        ^      |       ^
  //       |       |       |         |       |        |      |       |
  //       |       |       +---------|-------|--------+      +-------+
  //       |       +-----------------|-------+
  //       +-------------------------+
  ASSERT_OK(Flush());

  ASSERT_OK(db_->CompactRange(CompactRangeOptions(), /*begin=*/nullptr,
                              /*end=*/nullptr));

  // Due to the above sst partitioner, we get 4 L1 files. The blob files are
  // unchanged.
  //                             |'aaaa', 'bbbb', 'dddd'|  |'cccc'|
  //                                 ^       ^     ^         ^
  //                                 |       |     |         |
  // L0                              |       |     |         |
  // L1  ["a"]   ["b"]   ["c"]       |       |   ["d"]       |
  //       |       |       |         |       |               |
  //       |       |       +---------|-------|---------------+
  //       |       +-----------------|-------+
  //       +-------------------------+
  ASSERT_EQ(4, NumTableFilesAtLevel(/*level=*/1));

  {
    // Ingest the external SST file into bottommost level.
    std::vector<std::string> ext_files{file_path};
    IngestExternalFileOptions opts;
    opts.ingest_behind = true;
    ASSERT_OK(
        db_->IngestExternalFile(db_->DefaultColumnFamily(), ext_files, opts));
  }

  // Now the database becomes as follows.
  //                             |'aaaa', 'bbbb', 'dddd'|  |'cccc'|
  //                                 ^       ^     ^         ^
  //                                 |       |     |         |
  // L0                              |       |     |         |
  // L1  ["a"]   ["b"]   ["c"]       |       |   ["d"]       |
  //       |       |       |         |       |               |
  //       |       |       +---------|-------|---------------+
  //       |       +-----------------|-------+
  //       +-------------------------+
  //
  // L6          ["b"]

  {
    // Compact ["b"] to bottommost level.
    Slice begin = Slice(second_key);
    Slice end = Slice(second_key);
    CompactRangeOptions cro;
    cro.bottommost_level_compaction = BottommostLevelCompaction::kForce;
    ASSERT_OK(db_->CompactRange(cro, &begin, &end));
  }

  //                             |'aaaa', 'bbbb', 'dddd'|  |'cccc'|
  //                                 ^       ^     ^         ^
  //                                 |       |     |         |
  // L0                              |       |     |         |
  // L1  ["a"]           ["c"]       |       |   ["d"]       |
  //       |               |         |       |               |
  //       |               +---------|-------|---------------+
  //       |       +-----------------|-------+
  //       +-------|-----------------+
  //               |
  // L6          ["b"]
  ASSERT_EQ(3, NumTableFilesAtLevel(/*level=*/1));
  ASSERT_EQ(1, NumTableFilesAtLevel(/*level=*/6));

  bool called = false;
  SyncPoint::GetInstance()->ClearAllCallBacks();
  SyncPoint::GetInstance()->SetCallBack(
      "RandomAccessFileReader::MultiRead:AlignedReqs", [&](void* arg) {
        auto* aligned_reqs = static_cast<std::vector<FSReadRequest>*>(arg);
        assert(aligned_reqs);
        ASSERT_EQ(1, aligned_reqs->size());
        called = true;
      });
  SyncPoint::GetInstance()->EnableProcessing();

  std::array<Slice, num_keys> keys{{first_key, third_key, second_key}};

  {
    std::array<PinnableSlice, num_keys> values;
    std::array<Status, num_keys> statuses;

    // The MultiGet(), when constructing the KeyContexts, will process the keys
    // in such order: a, d, b. The reason is that ["a"] and ["d"] are in L1,
    // while ["b"] resides in L6.
    // Consequently, the original FSReadRequest list prepared by
    // Version::MultiGetblob() will be for "a", "d" and "b". It is unsorted as
    // follows:
    //
    // ["a", offset=30, len=3033],
    // ["d", offset=9096, len=3033],
    // ["b", offset=3063, len=6033]
    //
    // If we do not sort them before calling MultiRead() in DirectIO, then the
    // underlying IO merging logic will yield two requests.
    //
    // [offset=0, len=4096] (for "a")
    // [offset=0, len=12288] (result of merging the request for "d" and "b")
    //
    // We need to sort them in Version::MultiGetBlob() so that the underlying
    // IO merging logic in DirectIO mode works as expected. The correct
    // behavior will be one aligned request:
    //
    // [offset=0, len=12288]

    db_->MultiGet(ReadOptions(), db_->DefaultColumnFamily(), num_keys,
                  keys.data(), values.data(), statuses.data());

    SyncPoint::GetInstance()->DisableProcessing();
    SyncPoint::GetInstance()->ClearAllCallBacks();

    ASSERT_TRUE(called);

    ASSERT_OK(statuses[0]);
    ASSERT_EQ(values[0], first_blob);

    ASSERT_OK(statuses[1]);
    ASSERT_EQ(values[1], third_blob);

    ASSERT_OK(statuses[2]);
    ASSERT_EQ(values[2], second_blob);
  }
}

TEST_F(DBBlobBasicTest, MultiGetBlobsFromMultipleFiles) {
  Options options = GetDefaultOptions();

  LRUCacheOptions co;
  co.capacity = 2 << 20;  // 2MB
  co.num_shard_bits = 2;
  co.metadata_charge_policy = kDontChargeCacheMetadata;
  auto backing_cache = NewLRUCache(co);

  options.min_blob_size = 0;
  options.create_if_missing = true;
  options.enable_blob_files = true;
  options.blob_cache = backing_cache;

  BlockBasedTableOptions block_based_options;
  block_based_options.no_block_cache = false;
  block_based_options.block_cache = backing_cache;
  block_based_options.cache_index_and_filter_blocks = true;
  options.table_factory.reset(NewBlockBasedTableFactory(block_based_options));

  Reopen(options);

  constexpr size_t kNumBlobFiles = 3;
  constexpr size_t kNumBlobsPerFile = 3;
  constexpr size_t kNumKeys = kNumBlobsPerFile * kNumBlobFiles;

  std::vector<std::string> key_strs;
  std::vector<std::string> value_strs;
  for (size_t i = 0; i < kNumBlobFiles; ++i) {
    for (size_t j = 0; j < kNumBlobsPerFile; ++j) {
      std::string key = "key" + std::to_string(i) + "_" + std::to_string(j);
      std::string value =
          "value_as_blob" + std::to_string(i) + "_" + std::to_string(j);
      ASSERT_OK(Put(key, value));
      key_strs.push_back(key);
      value_strs.push_back(value);
    }
    ASSERT_OK(Flush());
  }
  assert(key_strs.size() == kNumKeys);
  std::array<Slice, kNumKeys> keys;
  for (size_t i = 0; i < keys.size(); ++i) {
    keys[i] = key_strs[i];
  }

  ReadOptions read_options;
  read_options.read_tier = kReadAllTier;
  read_options.fill_cache = false;

  {
    std::array<PinnableSlice, kNumKeys> values;
    std::array<Status, kNumKeys> statuses;
    db_->MultiGet(read_options, db_->DefaultColumnFamily(), kNumKeys,
                  keys.data(), values.data(), statuses.data());

    for (size_t i = 0; i < kNumKeys; ++i) {
      ASSERT_OK(statuses[i]);
      ASSERT_EQ(value_strs[i], values[i]);
    }
  }

  read_options.read_tier = kBlockCacheTier;

  {
    std::array<PinnableSlice, kNumKeys> values;
    std::array<Status, kNumKeys> statuses;
    db_->MultiGet(read_options, db_->DefaultColumnFamily(), kNumKeys,
                  keys.data(), values.data(), statuses.data());

    for (size_t i = 0; i < kNumKeys; ++i) {
      ASSERT_TRUE(statuses[i].IsIncomplete());
      ASSERT_TRUE(values[i].empty());
    }
  }

  read_options.read_tier = kReadAllTier;
  read_options.fill_cache = true;

  {
    std::array<PinnableSlice, kNumKeys> values;
    std::array<Status, kNumKeys> statuses;
    db_->MultiGet(read_options, db_->DefaultColumnFamily(), kNumKeys,
                  keys.data(), values.data(), statuses.data());

    for (size_t i = 0; i < kNumKeys; ++i) {
      ASSERT_OK(statuses[i]);
      ASSERT_EQ(value_strs[i], values[i]);
    }
  }

  read_options.read_tier = kBlockCacheTier;

  {
    std::array<PinnableSlice, kNumKeys> values;
    std::array<Status, kNumKeys> statuses;
    db_->MultiGet(read_options, db_->DefaultColumnFamily(), kNumKeys,
                  keys.data(), values.data(), statuses.data());

    for (size_t i = 0; i < kNumKeys; ++i) {
      ASSERT_OK(statuses[i]);
      ASSERT_EQ(value_strs[i], values[i]);
    }
  }
}

TEST_F(DBBlobBasicTest, GetBlob_CorruptIndex) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  constexpr char key[] = "key";
  constexpr char blob[] = "blob";

  ASSERT_OK(Put(key, blob));
  ASSERT_OK(Flush());

  SyncPoint::GetInstance()->SetCallBack(
      "Version::Get::TamperWithBlobIndex", [](void* arg) {
        Slice* const blob_index = static_cast<Slice*>(arg);
        assert(blob_index);
        assert(!blob_index->empty());
        blob_index->remove_prefix(1);
      });
  SyncPoint::GetInstance()->EnableProcessing();

  PinnableSlice result;
  ASSERT_TRUE(db_->Get(ReadOptions(), db_->DefaultColumnFamily(), key, &result)
                  .IsCorruption());

  SyncPoint::GetInstance()->DisableProcessing();
  SyncPoint::GetInstance()->ClearAllCallBacks();
}

TEST_F(DBBlobBasicTest, MultiGetBlob_CorruptIndex) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;
  options.create_if_missing = true;

  DestroyAndReopen(options);

  constexpr size_t kNumOfKeys = 3;
  std::array<std::string, kNumOfKeys> key_strs;
  std::array<std::string, kNumOfKeys> value_strs;
  std::array<Slice, kNumOfKeys + 1> keys;
  for (size_t i = 0; i < kNumOfKeys; ++i) {
    key_strs[i] = "foo" + std::to_string(i);
    value_strs[i] = "blob_value" + std::to_string(i);
    ASSERT_OK(Put(key_strs[i], value_strs[i]));
    keys[i] = key_strs[i];
  }

  constexpr char key[] = "key";
  constexpr char blob[] = "blob";
  ASSERT_OK(Put(key, blob));
  keys[kNumOfKeys] = key;

  ASSERT_OK(Flush());

  SyncPoint::GetInstance()->SetCallBack(
      "Version::MultiGet::TamperWithBlobIndex", [&key](void* arg) {
        KeyContext* const key_context = static_cast<KeyContext*>(arg);
        assert(key_context);
        assert(key_context->key);

        if (*(key_context->key) == key) {
          Slice* const blob_index = key_context->value;
          assert(blob_index);
          assert(!blob_index->empty());
          blob_index->remove_prefix(1);
        }
      });
  SyncPoint::GetInstance()->EnableProcessing();

  std::array<PinnableSlice, kNumOfKeys + 1> values;
  std::array<Status, kNumOfKeys + 1> statuses;
  db_->MultiGet(ReadOptions(), dbfull()->DefaultColumnFamily(), kNumOfKeys + 1,
                keys.data(), values.data(), statuses.data(),
                /*sorted_input=*/false);
  for (size_t i = 0; i < kNumOfKeys + 1; ++i) {
    if (i != kNumOfKeys) {
      ASSERT_OK(statuses[i]);
      ASSERT_EQ("blob_value" + std::to_string(i), values[i]);
    } else {
      ASSERT_TRUE(statuses[i].IsCorruption());
    }
  }

  SyncPoint::GetInstance()->DisableProcessing();
  SyncPoint::GetInstance()->ClearAllCallBacks();
}

TEST_F(DBBlobBasicTest, MultiGetBlob_ExceedSoftLimit) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  constexpr size_t kNumOfKeys = 3;
  std::array<std::string, kNumOfKeys> key_bufs;
  std::array<std::string, kNumOfKeys> value_bufs;
  std::array<Slice, kNumOfKeys> keys;
  for (size_t i = 0; i < kNumOfKeys; ++i) {
    key_bufs[i] = "foo" + std::to_string(i);
    value_bufs[i] = "blob_value" + std::to_string(i);
    ASSERT_OK(Put(key_bufs[i], value_bufs[i]));
    keys[i] = key_bufs[i];
  }
  ASSERT_OK(Flush());

  std::array<PinnableSlice, kNumOfKeys> values;
  std::array<Status, kNumOfKeys> statuses;
  ReadOptions read_opts;
  read_opts.value_size_soft_limit = 1;
  db_->MultiGet(read_opts, dbfull()->DefaultColumnFamily(), kNumOfKeys,
                keys.data(), values.data(), statuses.data(),
                /*sorted_input=*/true);
  for (const auto& s : statuses) {
    ASSERT_TRUE(s.IsAborted());
  }
}

TEST_F(DBBlobBasicTest, GetBlob_InlinedTTLIndex) {
  constexpr uint64_t min_blob_size = 10;

  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = min_blob_size;

  Reopen(options);

  constexpr char key[] = "key";
  constexpr char blob[] = "short";
  static_assert(sizeof(short) - 1 < min_blob_size,
                "Blob too long to be inlined");

  // Fake an inlined TTL blob index.
  std::string blob_index;

  constexpr uint64_t expiration = 1234567890;

  BlobIndex::EncodeInlinedTTL(&blob_index, expiration, blob);

  WriteBatch batch;
  ASSERT_OK(WriteBatchInternal::PutBlobIndex(&batch, 0, key, blob_index));
  ASSERT_OK(db_->Write(WriteOptions(), &batch));

  ASSERT_OK(Flush());

  PinnableSlice result;
  ASSERT_TRUE(db_->Get(ReadOptions(), db_->DefaultColumnFamily(), key, &result)
                  .IsCorruption());
}

TEST_F(DBBlobBasicTest, GetBlob_IndexWithInvalidFileNumber) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  constexpr char key[] = "key";

  // Fake a blob index referencing a non-existent blob file.
  std::string blob_index;

  constexpr uint64_t blob_file_number = 1000;
  constexpr uint64_t offset = 1234;
  constexpr uint64_t size = 5678;

  BlobIndex::EncodeBlob(&blob_index, blob_file_number, offset, size,
                        kNoCompression);

  WriteBatch batch;
  ASSERT_OK(WriteBatchInternal::PutBlobIndex(&batch, 0, key, blob_index));
  ASSERT_OK(db_->Write(WriteOptions(), &batch));

  ASSERT_OK(Flush());

  PinnableSlice result;
  ASSERT_TRUE(db_->Get(ReadOptions(), db_->DefaultColumnFamily(), key, &result)
                  .IsCorruption());
}

TEST_F(DBBlobBasicTest, GenerateIOTracing) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;
  std::string trace_file = dbname_ + "/io_trace_file";

  Reopen(options);
  {
    // Create IO trace file
    std::unique_ptr<TraceWriter> trace_writer;
    ASSERT_OK(
        NewFileTraceWriter(env_, EnvOptions(), trace_file, &trace_writer));
    ASSERT_OK(db_->StartIOTrace(TraceOptions(), std::move(trace_writer)));

    constexpr char key[] = "key";
    constexpr char blob_value[] = "blob_value";

    ASSERT_OK(Put(key, blob_value));
    ASSERT_OK(Flush());
    ASSERT_EQ(Get(key), blob_value);

    ASSERT_OK(db_->EndIOTrace());
    ASSERT_OK(env_->FileExists(trace_file));
  }
  {
    // Parse trace file to check file operations related to blob files are
    // recorded.
    std::unique_ptr<TraceReader> trace_reader;
    ASSERT_OK(
        NewFileTraceReader(env_, EnvOptions(), trace_file, &trace_reader));
    IOTraceReader reader(std::move(trace_reader));

    IOTraceHeader header;
    ASSERT_OK(reader.ReadHeader(&header));
    ASSERT_EQ(kMajorVersion, static_cast<int>(header.rocksdb_major_version));
    ASSERT_EQ(kMinorVersion, static_cast<int>(header.rocksdb_minor_version));

    // Read records.
    int blob_files_op_count = 0;
    Status status;
    while (true) {
      IOTraceRecord record;
      status = reader.ReadIOOp(&record);
      if (!status.ok()) {
        break;
      }
      if (record.file_name.find("blob") != std::string::npos) {
        blob_files_op_count++;
      }
    }
    // Assuming blob files will have Append, Close and then Read operations.
    ASSERT_GT(blob_files_op_count, 2);
  }
}

TEST_F(DBBlobBasicTest, BestEffortsRecovery_MissingNewestBlobFile) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;
  options.create_if_missing = true;
  Reopen(options);

  ASSERT_OK(dbfull()->DisableFileDeletions());
  constexpr int kNumTableFiles = 2;
  for (int i = 0; i < kNumTableFiles; ++i) {
    for (char ch = 'a'; ch != 'c'; ++ch) {
      std::string key(1, ch);
      ASSERT_OK(Put(key, "value" + std::to_string(i)));
    }
    ASSERT_OK(Flush());
  }

  Close();

  std::vector<std::string> files;
  ASSERT_OK(env_->GetChildren(dbname_, &files));
  std::string blob_file_path;
  uint64_t max_blob_file_num = kInvalidBlobFileNumber;
  for (const auto& fname : files) {
    uint64_t file_num = 0;
    FileType type;
    if (ParseFileName(fname, &file_num, /*info_log_name_prefix=*/"", &type) &&
        type == kBlobFile) {
      if (file_num > max_blob_file_num) {
        max_blob_file_num = file_num;
        blob_file_path = dbname_ + "/" + fname;
      }
    }
  }
  ASSERT_OK(env_->DeleteFile(blob_file_path));

  options.best_efforts_recovery = true;
  Reopen(options);
  std::string value;
  ASSERT_OK(db_->Get(ReadOptions(), "a", &value));
  ASSERT_EQ("value" + std::to_string(kNumTableFiles - 2), value);
}

TEST_F(DBBlobBasicTest, GetMergeBlobWithPut) {
  Options options = GetDefaultOptions();
  options.merge_operator = MergeOperators::CreateStringAppendOperator();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  ASSERT_OK(Put("Key1", "v1"));
  ASSERT_OK(Flush());
  ASSERT_OK(Merge("Key1", "v2"));
  ASSERT_OK(Flush());
  ASSERT_OK(Merge("Key1", "v3"));
  ASSERT_OK(Flush());

  std::string value;
  ASSERT_OK(db_->Get(ReadOptions(), "Key1", &value));
  ASSERT_EQ(Get("Key1"), "v1,v2,v3");
}

TEST_F(DBBlobBasicTest, GetMergeBlobFromMemoryTier) {
  Options options = GetDefaultOptions();
  options.merge_operator = MergeOperators::CreateStringAppendOperator();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  ASSERT_OK(Put(Key(0), "v1"));
  ASSERT_OK(Flush());
  ASSERT_OK(Merge(Key(0), "v2"));
  ASSERT_OK(Flush());

  // Regular `Get()` loads data block to cache.
  std::string value;
  ASSERT_OK(db_->Get(ReadOptions(), Key(0), &value));
  ASSERT_EQ("v1,v2", value);

  // Base value blob is still uncached, so an in-memory read will fail.
  ReadOptions read_options;
  read_options.read_tier = kBlockCacheTier;
  ASSERT_TRUE(db_->Get(read_options, Key(0), &value).IsIncomplete());
}

TEST_F(DBBlobBasicTest, MultiGetMergeBlobWithPut) {
  constexpr size_t num_keys = 3;

  Options options = GetDefaultOptions();
  options.merge_operator = MergeOperators::CreateStringAppendOperator();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  ASSERT_OK(Put("Key0", "v0_0"));
  ASSERT_OK(Put("Key1", "v1_0"));
  ASSERT_OK(Put("Key2", "v2_0"));
  ASSERT_OK(Flush());
  ASSERT_OK(Merge("Key0", "v0_1"));
  ASSERT_OK(Merge("Key1", "v1_1"));
  ASSERT_OK(Flush());
  ASSERT_OK(Merge("Key0", "v0_2"));
  ASSERT_OK(Flush());

  std::array<Slice, num_keys> keys{{"Key0", "Key1", "Key2"}};
  std::array<PinnableSlice, num_keys> values;
  std::array<Status, num_keys> statuses;

  db_->MultiGet(ReadOptions(), db_->DefaultColumnFamily(), num_keys,
                keys.data(), values.data(), statuses.data());

  ASSERT_OK(statuses[0]);
  ASSERT_EQ(values[0], "v0_0,v0_1,v0_2");

  ASSERT_OK(statuses[1]);
  ASSERT_EQ(values[1], "v1_0,v1_1");

  ASSERT_OK(statuses[2]);
  ASSERT_EQ(values[2], "v2_0");
}

TEST_F(DBBlobBasicTest, Properties) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  constexpr char key1[] = "key1";
  constexpr size_t key1_size = sizeof(key1) - 1;

  constexpr char key2[] = "key2";
  constexpr size_t key2_size = sizeof(key2) - 1;

  constexpr char key3[] = "key3";
  constexpr size_t key3_size = sizeof(key3) - 1;

  constexpr char blob[] = "00000000000000";
  constexpr size_t blob_size = sizeof(blob) - 1;

  constexpr char longer_blob[] = "00000000000000000000";
  constexpr size_t longer_blob_size = sizeof(longer_blob) - 1;

  ASSERT_OK(Put(key1, blob));
  ASSERT_OK(Put(key2, longer_blob));
  ASSERT_OK(Flush());

  constexpr size_t first_blob_file_expected_size =
      BlobLogHeader::kSize +
      BlobLogRecord::CalculateAdjustmentForRecordHeader(key1_size) + blob_size +
      BlobLogRecord::CalculateAdjustmentForRecordHeader(key2_size) +
      longer_blob_size + BlobLogFooter::kSize;

  ASSERT_OK(Put(key3, blob));
  ASSERT_OK(Flush());

  constexpr size_t second_blob_file_expected_size =
      BlobLogHeader::kSize +
      BlobLogRecord::CalculateAdjustmentForRecordHeader(key3_size) + blob_size +
      BlobLogFooter::kSize;

  constexpr size_t total_expected_size =
      first_blob_file_expected_size + second_blob_file_expected_size;

  // Number of blob files
  uint64_t num_blob_files = 0;
  ASSERT_TRUE(
      db_->GetIntProperty(DB::Properties::kNumBlobFiles, &num_blob_files));
  ASSERT_EQ(num_blob_files, 2);

  // Total size of live blob files
  uint64_t live_blob_file_size = 0;
  ASSERT_TRUE(db_->GetIntProperty(DB::Properties::kLiveBlobFileSize,
                                  &live_blob_file_size));
  ASSERT_EQ(live_blob_file_size, total_expected_size);

  // Total amount of garbage in live blob files
  {
    uint64_t live_blob_file_garbage_size = 0;
    ASSERT_TRUE(db_->GetIntProperty(DB::Properties::kLiveBlobFileGarbageSize,
                                    &live_blob_file_garbage_size));
    ASSERT_EQ(live_blob_file_garbage_size, 0);
  }

  // Total size of all blob files across all versions
  // Note: this should be the same as above since we only have one
  // version at this point.
  uint64_t total_blob_file_size = 0;
  ASSERT_TRUE(db_->GetIntProperty(DB::Properties::kTotalBlobFileSize,
                                  &total_blob_file_size));
  ASSERT_EQ(total_blob_file_size, total_expected_size);

  // Delete key2 to create some garbage
  ASSERT_OK(Delete(key2));
  ASSERT_OK(Flush());

  constexpr Slice* begin = nullptr;
  constexpr Slice* end = nullptr;
  ASSERT_OK(db_->CompactRange(CompactRangeOptions(), begin, end));

  constexpr size_t expected_garbage_size =
      BlobLogRecord::CalculateAdjustmentForRecordHeader(key2_size) +
      longer_blob_size;

  constexpr double expected_space_amp =
      static_cast<double>(total_expected_size) /
      (total_expected_size - expected_garbage_size);

  // Blob file stats
  std::string blob_stats;
  ASSERT_TRUE(db_->GetProperty(DB::Properties::kBlobStats, &blob_stats));

  std::ostringstream oss;
  oss << "Number of blob files: 2\nTotal size of blob files: "
      << total_expected_size
      << "\nTotal size of garbage in blob files: " << expected_garbage_size
      << "\nBlob file space amplification: " << expected_space_amp << '\n';

  ASSERT_EQ(blob_stats, oss.str());

  // Total amount of garbage in live blob files
  {
    uint64_t live_blob_file_garbage_size = 0;
    ASSERT_TRUE(db_->GetIntProperty(DB::Properties::kLiveBlobFileGarbageSize,
                                    &live_blob_file_garbage_size));
    ASSERT_EQ(live_blob_file_garbage_size, expected_garbage_size);
  }
}

TEST_F(DBBlobBasicTest, PropertiesMultiVersion) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  constexpr char key1[] = "key1";
  constexpr char key2[] = "key2";
  constexpr char key3[] = "key3";

  constexpr size_t key_size = sizeof(key1) - 1;
  static_assert(sizeof(key2) - 1 == key_size, "unexpected size: key2");
  static_assert(sizeof(key3) - 1 == key_size, "unexpected size: key3");

  constexpr char blob[] = "0000000000";
  constexpr size_t blob_size = sizeof(blob) - 1;

  ASSERT_OK(Put(key1, blob));
  ASSERT_OK(Flush());

  ASSERT_OK(Put(key2, blob));
  ASSERT_OK(Flush());

  // Create an iterator to keep the current version alive
  std::unique_ptr<Iterator> iter(db_->NewIterator(ReadOptions()));
  ASSERT_OK(iter->status());

  // Note: the Delete and subsequent compaction results in the first blob file
  // not making it to the final version. (It is still part of the previous
  // version kept alive by the iterator though.) On the other hand, the Put
  // results in a third blob file.
  ASSERT_OK(Delete(key1));
  ASSERT_OK(Put(key3, blob));
  ASSERT_OK(Flush());

  constexpr Slice* begin = nullptr;
  constexpr Slice* end = nullptr;
  ASSERT_OK(db_->CompactRange(CompactRangeOptions(), begin, end));

  // Total size of all blob files across all versions: between the two versions,
  // we should have three blob files of the same size with one blob each.
  // The version kept alive by the iterator contains the first and the second
  // blob file, while the final version contains the second and the third blob
  // file. (The second blob file is thus shared by the two versions but should
  // be counted only once.)
  uint64_t total_blob_file_size = 0;
  ASSERT_TRUE(db_->GetIntProperty(DB::Properties::kTotalBlobFileSize,
                                  &total_blob_file_size));
  ASSERT_EQ(total_blob_file_size,
            3 * (BlobLogHeader::kSize +
                 BlobLogRecord::CalculateAdjustmentForRecordHeader(key_size) +
                 blob_size + BlobLogFooter::kSize));
}

class DBBlobBasicIOErrorTest : public DBBlobBasicTest,
                               public testing::WithParamInterface<std::string> {
 protected:
  DBBlobBasicIOErrorTest() : sync_point_(GetParam()) {
    fault_injection_env_.reset(new FaultInjectionTestEnv(env_));
  }
  ~DBBlobBasicIOErrorTest() { Close(); }

  std::unique_ptr<FaultInjectionTestEnv> fault_injection_env_;
  std::string sync_point_;
};

class DBBlobBasicIOErrorMultiGetTest : public DBBlobBasicIOErrorTest {
 public:
  DBBlobBasicIOErrorMultiGetTest() : DBBlobBasicIOErrorTest() {}
};

INSTANTIATE_TEST_CASE_P(DBBlobBasicTest, DBBlobBasicIOErrorTest,
                        ::testing::ValuesIn(std::vector<std::string>{
                            "BlobFileReader::OpenFile:NewRandomAccessFile",
                            "BlobFileReader::GetBlob:ReadFromFile"}));

INSTANTIATE_TEST_CASE_P(DBBlobBasicTest, DBBlobBasicIOErrorMultiGetTest,
                        ::testing::ValuesIn(std::vector<std::string>{
                            "BlobFileReader::OpenFile:NewRandomAccessFile",
                            "BlobFileReader::MultiGetBlob:ReadFromFile"}));

TEST_P(DBBlobBasicIOErrorTest, GetBlob_IOError) {
  Options options;
  options.env = fault_injection_env_.get();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  constexpr char key[] = "key";
  constexpr char blob_value[] = "blob_value";

  ASSERT_OK(Put(key, blob_value));

  ASSERT_OK(Flush());

  SyncPoint::GetInstance()->SetCallBack(sync_point_, [this](void* /* arg */) {
    fault_injection_env_->SetFilesystemActive(false,
                                              Status::IOError(sync_point_));
  });
  SyncPoint::GetInstance()->EnableProcessing();

  PinnableSlice result;
  ASSERT_TRUE(db_->Get(ReadOptions(), db_->DefaultColumnFamily(), key, &result)
                  .IsIOError());

  SyncPoint::GetInstance()->DisableProcessing();
  SyncPoint::GetInstance()->ClearAllCallBacks();
}

TEST_P(DBBlobBasicIOErrorMultiGetTest, MultiGetBlobs_IOError) {
  Options options = GetDefaultOptions();
  options.env = fault_injection_env_.get();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  constexpr size_t num_keys = 2;

  constexpr char first_key[] = "first_key";
  constexpr char first_value[] = "first_value";

  ASSERT_OK(Put(first_key, first_value));

  constexpr char second_key[] = "second_key";
  constexpr char second_value[] = "second_value";

  ASSERT_OK(Put(second_key, second_value));

  ASSERT_OK(Flush());

  std::array<Slice, num_keys> keys{{first_key, second_key}};
  std::array<PinnableSlice, num_keys> values;
  std::array<Status, num_keys> statuses;

  SyncPoint::GetInstance()->SetCallBack(sync_point_, [this](void* /* arg */) {
    fault_injection_env_->SetFilesystemActive(false,
                                              Status::IOError(sync_point_));
  });
  SyncPoint::GetInstance()->EnableProcessing();

  db_->MultiGet(ReadOptions(), db_->DefaultColumnFamily(), num_keys,
                keys.data(), values.data(), statuses.data());

  SyncPoint::GetInstance()->DisableProcessing();
  SyncPoint::GetInstance()->ClearAllCallBacks();

  ASSERT_TRUE(statuses[0].IsIOError());
  ASSERT_TRUE(statuses[1].IsIOError());
}

TEST_P(DBBlobBasicIOErrorMultiGetTest, MultipleBlobFiles) {
  Options options = GetDefaultOptions();
  options.env = fault_injection_env_.get();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  constexpr size_t num_keys = 2;

  constexpr char key1[] = "key1";
  constexpr char value1[] = "blob1";

  ASSERT_OK(Put(key1, value1));
  ASSERT_OK(Flush());

  constexpr char key2[] = "key2";
  constexpr char value2[] = "blob2";

  ASSERT_OK(Put(key2, value2));
  ASSERT_OK(Flush());

  std::array<Slice, num_keys> keys{{key1, key2}};
  std::array<PinnableSlice, num_keys> values;
  std::array<Status, num_keys> statuses;

  bool first_blob_file = true;
  SyncPoint::GetInstance()->SetCallBack(
      sync_point_, [&first_blob_file, this](void* /* arg */) {
        if (first_blob_file) {
          first_blob_file = false;
          return;
        }
        fault_injection_env_->SetFilesystemActive(false,
                                                  Status::IOError(sync_point_));
      });
  SyncPoint::GetInstance()->EnableProcessing();

  db_->MultiGet(ReadOptions(), db_->DefaultColumnFamily(), num_keys,
                keys.data(), values.data(), statuses.data());
  SyncPoint::GetInstance()->DisableProcessing();
  SyncPoint::GetInstance()->ClearAllCallBacks();
  ASSERT_OK(statuses[0]);
  ASSERT_EQ(value1, values[0]);
  ASSERT_TRUE(statuses[1].IsIOError());
}

TEST_F(DBBlobBasicTest, MultiGetFindTable_IOError) {
  // Repro test for a specific bug where `MultiGet()` would fail to open a table
  // in `FindTable()` and then proceed to return raw blob handles for the other
  // keys.
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  // Force no table cache so every read will preload the SST file.
  dbfull()->TEST_table_cache()->SetCapacity(0);

  constexpr size_t num_keys = 2;

  constexpr char key1[] = "key1";
  constexpr char value1[] = "blob1";

  ASSERT_OK(Put(key1, value1));
  ASSERT_OK(Flush());

  constexpr char key2[] = "key2";
  constexpr char value2[] = "blob2";

  ASSERT_OK(Put(key2, value2));
  ASSERT_OK(Flush());

  std::atomic<int> num_files_opened = 0;
  // This test would be more realistic if we injected an `IOError` from the
  // `FileSystem`
  SyncPoint::GetInstance()->SetCallBack(
      "TableCache::MultiGet:FindTable", [&](void* status) {
        num_files_opened++;
        if (num_files_opened == 2) {
          Status* s = static_cast<Status*>(status);
          *s = Status::IOError();
        }
      });
  SyncPoint::GetInstance()->EnableProcessing();

  std::array<Slice, num_keys> keys{{key1, key2}};
  std::array<PinnableSlice, num_keys> values;
  std::array<Status, num_keys> statuses;
  db_->MultiGet(ReadOptions(), db_->DefaultColumnFamily(), num_keys,
                keys.data(), values.data(), statuses.data());

  ASSERT_TRUE(statuses[0].IsIOError());
  ASSERT_OK(statuses[1]);
  ASSERT_EQ(value2, values[1]);
}

namespace {

class ReadBlobCompactionFilter : public CompactionFilter {
 public:
  ReadBlobCompactionFilter() = default;
  const char* Name() const override {
    return "rocksdb.compaction.filter.read.blob";
  }
  CompactionFilter::Decision FilterV2(
      int /*level*/, const Slice& /*key*/, ValueType value_type,
      const Slice& existing_value, std::string* new_value,
      std::string* /*skip_until*/) const override {
    if (value_type != CompactionFilter::ValueType::kValue) {
      return CompactionFilter::Decision::kKeep;
    }
    assert(new_value);
    new_value->assign(existing_value.data(), existing_value.size());
    return CompactionFilter::Decision::kChangeValue;
  }
};

}  // anonymous namespace

TEST_P(DBBlobBasicIOErrorTest, CompactionFilterReadBlob_IOError) {
  Options options = GetDefaultOptions();
  options.env = fault_injection_env_.get();
  options.enable_blob_files = true;
  options.min_blob_size = 0;
  options.create_if_missing = true;
  std::unique_ptr<CompactionFilter> compaction_filter_guard(
      new ReadBlobCompactionFilter);
  options.compaction_filter = compaction_filter_guard.get();

  DestroyAndReopen(options);
  constexpr char key[] = "foo";
  constexpr char blob_value[] = "foo_blob_value";
  ASSERT_OK(Put(key, blob_value));
  ASSERT_OK(Flush());

  SyncPoint::GetInstance()->SetCallBack(sync_point_, [this](void* /* arg */) {
    fault_injection_env_->SetFilesystemActive(false,
                                              Status::IOError(sync_point_));
  });
  SyncPoint::GetInstance()->EnableProcessing();

  ASSERT_TRUE(db_->CompactRange(CompactRangeOptions(), /*begin=*/nullptr,
                                /*end=*/nullptr)
                  .IsIOError());

  SyncPoint::GetInstance()->DisableProcessing();
  SyncPoint::GetInstance()->ClearAllCallBacks();
}

TEST_P(DBBlobBasicIOErrorTest, IterateBlobsAllowUnpreparedValue_IOError) {
  Options options;
  options.env = fault_injection_env_.get();
  options.enable_blob_files = true;

  Reopen(options);

  constexpr char key[] = "key";
  constexpr char blob_value[] = "blob_value";

  ASSERT_OK(Put(key, blob_value));

  ASSERT_OK(Flush());

  SyncPoint::GetInstance()->SetCallBack(sync_point_, [this](void* /* arg */) {
    fault_injection_env_->SetFilesystemActive(false,
                                              Status::IOError(sync_point_));
  });
  SyncPoint::GetInstance()->EnableProcessing();

  ReadOptions read_options;
  read_options.allow_unprepared_value = true;

  std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
  iter->SeekToFirst();

  ASSERT_TRUE(iter->Valid());
  ASSERT_EQ(iter->key(), key);
  ASSERT_TRUE(iter->value().empty());
  ASSERT_OK(iter->status());

  ASSERT_FALSE(iter->PrepareValue());

  ASSERT_FALSE(iter->Valid());
  ASSERT_TRUE(iter->status().IsIOError());

  SyncPoint::GetInstance()->DisableProcessing();
  SyncPoint::GetInstance()->ClearAllCallBacks();
}

TEST_F(DBBlobBasicTest, WarmCacheWithBlobsDuringFlush) {
  Options options = GetDefaultOptions();

  LRUCacheOptions co;
  co.capacity = 1 << 25;
  co.num_shard_bits = 2;
  co.metadata_charge_policy = kDontChargeCacheMetadata;
  auto backing_cache = NewLRUCache(co);

  options.blob_cache = backing_cache;

  BlockBasedTableOptions block_based_options;
  block_based_options.no_block_cache = false;
  block_based_options.block_cache = backing_cache;
  block_based_options.cache_index_and_filter_blocks = true;
  options.table_factory.reset(NewBlockBasedTableFactory(block_based_options));

  options.enable_blob_files = true;
  options.create_if_missing = true;
  options.disable_auto_compactions = true;
  options.enable_blob_garbage_collection = true;
  options.blob_garbage_collection_age_cutoff = 1.0;
  options.prepopulate_blob_cache = PrepopulateBlobCache::kFlushOnly;
  options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();

  DestroyAndReopen(options);

  constexpr size_t kNumBlobs = 10;
  constexpr size_t kValueSize = 100;

  std::string value(kValueSize, 'a');

  for (size_t i = 1; i <= kNumBlobs; i++) {
    ASSERT_OK(Put(std::to_string(i), value));
    ASSERT_OK(Put(std::to_string(i + kNumBlobs), value));  // Add some overlap
    ASSERT_OK(Flush());
    ASSERT_EQ(i * 2, options.statistics->getTickerCount(BLOB_DB_CACHE_ADD));
    ASSERT_EQ(value, Get(std::to_string(i)));
    ASSERT_EQ(value, Get(std::to_string(i + kNumBlobs)));
    ASSERT_EQ(0, options.statistics->getTickerCount(BLOB_DB_CACHE_MISS));
    ASSERT_EQ(i * 2, options.statistics->getTickerCount(BLOB_DB_CACHE_HIT));
  }

  // Verify compaction not counted
  ASSERT_OK(db_->CompactRange(CompactRangeOptions(), /*begin=*/nullptr,
                              /*end=*/nullptr));
  EXPECT_EQ(kNumBlobs * 2,
            options.statistics->getTickerCount(BLOB_DB_CACHE_ADD));
}

TEST_F(DBBlobBasicTest, DynamicallyWarmCacheDuringFlush) {
  Options options = GetDefaultOptions();

  LRUCacheOptions co;
  co.capacity = 1 << 25;
  co.num_shard_bits = 2;
  co.metadata_charge_policy = kDontChargeCacheMetadata;
  auto backing_cache = NewLRUCache(co);

  options.blob_cache = backing_cache;

  BlockBasedTableOptions block_based_options;
  block_based_options.no_block_cache = false;
  block_based_options.block_cache = backing_cache;
  block_based_options.cache_index_and_filter_blocks = true;
  options.table_factory.reset(NewBlockBasedTableFactory(block_based_options));

  options.enable_blob_files = true;
  options.create_if_missing = true;
  options.disable_auto_compactions = true;
  options.enable_blob_garbage_collection = true;
  options.blob_garbage_collection_age_cutoff = 1.0;
  options.prepopulate_blob_cache = PrepopulateBlobCache::kFlushOnly;
  options.statistics = ROCKSDB_NAMESPACE::CreateDBStatistics();

  DestroyAndReopen(options);

  constexpr size_t kNumBlobs = 10;
  constexpr size_t kValueSize = 100;

  std::string value(kValueSize, 'a');

  for (size_t i = 1; i <= 5; i++) {
    ASSERT_OK(Put(std::to_string(i), value));
    ASSERT_OK(Put(std::to_string(i + kNumBlobs), value));  // Add some overlap
    ASSERT_OK(Flush());
    ASSERT_EQ(2, options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_ADD));

    ASSERT_EQ(value, Get(std::to_string(i)));
    ASSERT_EQ(value, Get(std::to_string(i + kNumBlobs)));
    ASSERT_EQ(0, options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_ADD));
    ASSERT_EQ(0,
              options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_MISS));
    ASSERT_EQ(2, options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_HIT));
  }

  ASSERT_OK(dbfull()->SetOptions({{"prepopulate_blob_cache", "kDisable"}}));

  for (size_t i = 6; i <= kNumBlobs; i++) {
    ASSERT_OK(Put(std::to_string(i), value));
    ASSERT_OK(Put(std::to_string(i + kNumBlobs), value));  // Add some overlap
    ASSERT_OK(Flush());
    ASSERT_EQ(0, options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_ADD));

    ASSERT_EQ(value, Get(std::to_string(i)));
    ASSERT_EQ(value, Get(std::to_string(i + kNumBlobs)));
    ASSERT_EQ(2, options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_ADD));
    ASSERT_EQ(2,
              options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_MISS));
    ASSERT_EQ(0, options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_HIT));
  }

  // Verify compaction not counted
  ASSERT_OK(db_->CompactRange(CompactRangeOptions(), /*begin=*/nullptr,
                              /*end=*/nullptr));
  EXPECT_EQ(0, options.statistics->getTickerCount(BLOB_DB_CACHE_ADD));
}

TEST_F(DBBlobBasicTest, WarmCacheWithBlobsSecondary) {
  CompressedSecondaryCacheOptions secondary_cache_opts;
  secondary_cache_opts.capacity = 1 << 20;
  secondary_cache_opts.num_shard_bits = 0;
  secondary_cache_opts.metadata_charge_policy = kDontChargeCacheMetadata;
  secondary_cache_opts.compression_type = kNoCompression;

  LRUCacheOptions primary_cache_opts;
  primary_cache_opts.capacity = 1024;
  primary_cache_opts.num_shard_bits = 0;
  primary_cache_opts.metadata_charge_policy = kDontChargeCacheMetadata;
  primary_cache_opts.secondary_cache =
      NewCompressedSecondaryCache(secondary_cache_opts);

  Options options = GetDefaultOptions();
  options.create_if_missing = true;
  options.statistics = CreateDBStatistics();
  options.enable_blob_files = true;
  options.blob_cache = NewLRUCache(primary_cache_opts);
  options.prepopulate_blob_cache = PrepopulateBlobCache::kFlushOnly;

  DestroyAndReopen(options);

  // Note: only one of the two blobs fit in the primary cache at any given time.
  constexpr char first_key[] = "foo";
  constexpr size_t first_blob_size = 512;
  const std::string first_blob(first_blob_size, 'a');

  constexpr char second_key[] = "bar";
  constexpr size_t second_blob_size = 768;
  const std::string second_blob(second_blob_size, 'b');

  // First blob is inserted into primary cache during flush.
  ASSERT_OK(Put(first_key, first_blob));
  ASSERT_OK(Flush());
  ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_ADD), 1);

  // Second blob is inserted into primary cache during flush,
  // First blob is evicted but only a dummy handle is inserted into secondary
  // cache.
  ASSERT_OK(Put(second_key, second_blob));
  ASSERT_OK(Flush());
  ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_ADD), 1);

  // First blob is inserted into primary cache.
  // Second blob is evicted but only a dummy handle is inserted into secondary
  // cache.
  ASSERT_EQ(Get(first_key), first_blob);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_MISS), 1);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_HIT), 0);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(SECONDARY_CACHE_HITS),
            0);
  // Second blob is inserted into primary cache,
  // First blob is evicted and is inserted into secondary cache.
  ASSERT_EQ(Get(second_key), second_blob);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_MISS), 1);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_HIT), 0);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(SECONDARY_CACHE_HITS),
            0);

  // First blob's dummy item is inserted into primary cache b/c of lookup.
  // Second blob is still in primary cache.
  ASSERT_EQ(Get(first_key), first_blob);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_MISS), 0);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_HIT), 1);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(SECONDARY_CACHE_HITS),
            1);

  // First blob's item is inserted into primary cache b/c of lookup.
  // Second blob is evicted and inserted into secondary cache.
  ASSERT_EQ(Get(first_key), first_blob);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_MISS), 0);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(BLOB_DB_CACHE_HIT), 1);
  ASSERT_EQ(options.statistics->getAndResetTickerCount(SECONDARY_CACHE_HITS),
            1);
}

TEST_F(DBBlobBasicTest, GetEntityBlob) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = 0;

  Reopen(options);

  constexpr char key[] = "key";
  constexpr char blob_value[] = "blob_value";

  constexpr char other_key[] = "other_key";
  constexpr char other_blob_value[] = "other_blob_value";

  ASSERT_OK(Put(key, blob_value));
  ASSERT_OK(Put(other_key, other_blob_value));

  ASSERT_OK(Flush());

  WideColumns expected_columns{{kDefaultWideColumnName, blob_value}};
  WideColumns other_expected_columns{
      {kDefaultWideColumnName, other_blob_value}};

  {
    PinnableWideColumns result;
    ASSERT_OK(db_->GetEntity(ReadOptions(), db_->DefaultColumnFamily(), key,
                             &result));
    ASSERT_EQ(result.columns(), expected_columns);
  }

  {
    PinnableWideColumns result;
    ASSERT_OK(db_->GetEntity(ReadOptions(), db_->DefaultColumnFamily(),
                             other_key, &result));

    ASSERT_EQ(result.columns(), other_expected_columns);
  }

  {
    constexpr size_t num_keys = 2;

    std::array<Slice, num_keys> keys{{key, other_key}};
    std::array<PinnableWideColumns, num_keys> results;
    std::array<Status, num_keys> statuses;

    db_->MultiGetEntity(ReadOptions(), db_->DefaultColumnFamily(), num_keys,
                        keys.data(), results.data(), statuses.data());

    ASSERT_OK(statuses[0]);
    ASSERT_EQ(results[0].columns(), expected_columns);

    ASSERT_OK(statuses[1]);
    ASSERT_EQ(results[1].columns(), other_expected_columns);
  }
}

class DBBlobWithTimestampTest : public DBBasicTestWithTimestampBase {
 protected:
  DBBlobWithTimestampTest()
      : DBBasicTestWithTimestampBase("db_blob_with_timestamp_test") {}
};

TEST_F(DBBlobWithTimestampTest, GetBlob) {
  Options options = GetDefaultOptions();
  options.create_if_missing = true;
  options.enable_blob_files = true;
  options.min_blob_size = 0;
  const size_t kTimestampSize = Timestamp(0, 0).size();
  TestComparator test_cmp(kTimestampSize);
  options.comparator = &test_cmp;

  DestroyAndReopen(options);
  WriteOptions write_opts;
  const std::string ts = Timestamp(1, 0);
  constexpr char key[] = "key";
  constexpr char blob_value[] = "blob_value";

  ASSERT_OK(db_->Put(write_opts, key, ts, blob_value));

  ASSERT_OK(Flush());

  const std::string read_ts = Timestamp(2, 0);
  Slice read_ts_slice(read_ts);
  ReadOptions read_opts;
  read_opts.timestamp = &read_ts_slice;
  std::string value;
  ASSERT_OK(db_->Get(read_opts, key, &value));
  ASSERT_EQ(value, blob_value);
}

TEST_F(DBBlobWithTimestampTest, MultiGetBlobs) {
  constexpr size_t min_blob_size = 6;

  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.min_blob_size = min_blob_size;
  options.create_if_missing = true;
  const size_t kTimestampSize = Timestamp(0, 0).size();
  TestComparator test_cmp(kTimestampSize);
  options.comparator = &test_cmp;

  DestroyAndReopen(options);

  // Put then retrieve three key-values. The first value is below the size limit
  // and is thus stored inline; the other two are stored separately as blobs.
  constexpr size_t num_keys = 3;

  constexpr char first_key[] = "first_key";
  constexpr char first_value[] = "short";
  static_assert(sizeof(first_value) - 1 < min_blob_size,
                "first_value too long to be inlined");

  DestroyAndReopen(options);
  WriteOptions write_opts;
  const std::string ts = Timestamp(1, 0);
  ASSERT_OK(db_->Put(write_opts, first_key, ts, first_value));

  constexpr char second_key[] = "second_key";
  constexpr char second_value[] = "long_value";
  static_assert(sizeof(second_value) - 1 >= min_blob_size,
                "second_value too short to be stored as blob");

  ASSERT_OK(db_->Put(write_opts, second_key, ts, second_value));

  constexpr char third_key[] = "third_key";
  constexpr char third_value[] = "other_long_value";
  static_assert(sizeof(third_value) - 1 >= min_blob_size,
                "third_value too short to be stored as blob");

  ASSERT_OK(db_->Put(write_opts, third_key, ts, third_value));

  ASSERT_OK(Flush());

  ReadOptions read_options;
  const std::string read_ts = Timestamp(2, 0);
  Slice read_ts_slice(read_ts);
  read_options.timestamp = &read_ts_slice;
  std::array<Slice, num_keys> keys{{first_key, second_key, third_key}};

  {
    std::array<PinnableSlice, num_keys> values;
    std::array<Status, num_keys> statuses;

    db_->MultiGet(read_options, db_->DefaultColumnFamily(), num_keys,
                  keys.data(), values.data(), statuses.data());

    ASSERT_OK(statuses[0]);
    ASSERT_EQ(values[0], first_value);

    ASSERT_OK(statuses[1]);
    ASSERT_EQ(values[1], second_value);

    ASSERT_OK(statuses[2]);
    ASSERT_EQ(values[2], third_value);
  }
}

TEST_F(DBBlobWithTimestampTest, GetMergeBlobWithPut) {
  Options options = GetDefaultOptions();
  options.merge_operator = MergeOperators::CreateStringAppendOperator();
  options.enable_blob_files = true;
  options.min_blob_size = 0;
  options.create_if_missing = true;
  const size_t kTimestampSize = Timestamp(0, 0).size();
  TestComparator test_cmp(kTimestampSize);
  options.comparator = &test_cmp;

  DestroyAndReopen(options);

  WriteOptions write_opts;
  const std::string ts = Timestamp(1, 0);
  ASSERT_OK(db_->Put(write_opts, "Key1", ts, "v1"));
  ASSERT_OK(Flush());
  ASSERT_OK(
      db_->Merge(write_opts, db_->DefaultColumnFamily(), "Key1", ts, "v2"));
  ASSERT_OK(Flush());
  ASSERT_OK(
      db_->Merge(write_opts, db_->DefaultColumnFamily(), "Key1", ts, "v3"));
  ASSERT_OK(Flush());

  std::string value;
  const std::string read_ts = Timestamp(2, 0);
  Slice read_ts_slice(read_ts);
  ReadOptions read_opts;
  read_opts.timestamp = &read_ts_slice;
  ASSERT_OK(db_->Get(read_opts, "Key1", &value));
  ASSERT_EQ(value, "v1,v2,v3");
}

TEST_F(DBBlobWithTimestampTest, MultiGetMergeBlobWithPut) {
  constexpr size_t num_keys = 3;

  Options options = GetDefaultOptions();
  options.merge_operator = MergeOperators::CreateStringAppendOperator();
  options.enable_blob_files = true;
  options.min_blob_size = 0;
  options.create_if_missing = true;
  const size_t kTimestampSize = Timestamp(0, 0).size();
  TestComparator test_cmp(kTimestampSize);
  options.comparator = &test_cmp;

  DestroyAndReopen(options);

  WriteOptions write_opts;
  const std::string ts = Timestamp(1, 0);

  ASSERT_OK(db_->Put(write_opts, "Key0", ts, "v0_0"));
  ASSERT_OK(db_->Put(write_opts, "Key1", ts, "v1_0"));
  ASSERT_OK(db_->Put(write_opts, "Key2", ts, "v2_0"));
  ASSERT_OK(Flush());
  ASSERT_OK(
      db_->Merge(write_opts, db_->DefaultColumnFamily(), "Key0", ts, "v0_1"));
  ASSERT_OK(
      db_->Merge(write_opts, db_->DefaultColumnFamily(), "Key1", ts, "v1_1"));
  ASSERT_OK(Flush());
  ASSERT_OK(
      db_->Merge(write_opts, db_->DefaultColumnFamily(), "Key0", ts, "v0_2"));
  ASSERT_OK(Flush());

  const std::string read_ts = Timestamp(2, 0);
  Slice read_ts_slice(read_ts);
  ReadOptions read_opts;
  read_opts.timestamp = &read_ts_slice;
  std::array<Slice, num_keys> keys{{"Key0", "Key1", "Key2"}};
  std::array<PinnableSlice, num_keys> values;
  std::array<Status, num_keys> statuses;

  db_->MultiGet(read_opts, db_->DefaultColumnFamily(), num_keys, keys.data(),
                values.data(), statuses.data());

  ASSERT_OK(statuses[0]);
  ASSERT_EQ(values[0], "v0_0,v0_1,v0_2");

  ASSERT_OK(statuses[1]);
  ASSERT_EQ(values[1], "v1_0,v1_1");

  ASSERT_OK(statuses[2]);
  ASSERT_EQ(values[2], "v2_0");
}

TEST_F(DBBlobWithTimestampTest, IterateBlobs) {
  Options options = GetDefaultOptions();
  options.enable_blob_files = true;
  options.create_if_missing = true;
  const size_t kTimestampSize = Timestamp(0, 0).size();
  TestComparator test_cmp(kTimestampSize);
  options.comparator = &test_cmp;

  DestroyAndReopen(options);

  int num_blobs = 5;
  std::vector<std::string> keys;
  std::vector<std::string> blobs;

  WriteOptions write_opts;
  std::vector<std::string> write_timestamps = {Timestamp(1, 0),
                                               Timestamp(2, 0)};

  // For each key in ["key0", ... "keyi", ...], write two versions:
  // Timestamp(1, 0), "blobi0"
  // Timestamp(2, 0), "blobi1"
  for (int i = 0; i < num_blobs; i++) {
    keys.push_back("key" + std::to_string(i));
    blobs.push_back("blob" + std::to_string(i));
    for (size_t j = 0; j < write_timestamps.size(); j++) {
      ASSERT_OK(db_->Put(write_opts, keys[i], write_timestamps[j],
                         blobs[i] + std::to_string(j)));
    }
  }
  ASSERT_OK(Flush());

  ReadOptions read_options;
  std::vector<std::string> read_timestamps = {Timestamp(0, 0), Timestamp(3, 0)};
  Slice ts_upper_bound(read_timestamps[1]);
  read_options.timestamp = &ts_upper_bound;

  auto check_iter_entry =
      [](const Iterator* iter, const std::string& expected_key,
         const std::string& expected_ts, const std::string& expected_value,
         bool key_is_internal = true) {
        ASSERT_OK(iter->status());
        if (key_is_internal) {
          std::string expected_ukey_and_ts;
          expected_ukey_and_ts.assign(expected_key.data(), expected_key.size());
          expected_ukey_and_ts.append(expected_ts.data(), expected_ts.size());

          ParsedInternalKey parsed_ikey;
          ASSERT_OK(ParseInternalKey(iter->key(), &parsed_ikey,
                                     true /* log_err_key */));
          ASSERT_EQ(parsed_ikey.user_key, expected_ukey_and_ts);
        } else {
          ASSERT_EQ(iter->key(), expected_key);
        }
        ASSERT_EQ(iter->timestamp(), expected_ts);
        ASSERT_EQ(iter->value(), expected_value);
      };

  // Forward iterating one version of each key, get in this order:
  // [("key0", Timestamp(2, 0), "blob01"),
  //  ("key1", Timestamp(2, 0), "blob11")...]
  {
    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    iter->SeekToFirst();
    for (int i = 0; i < num_blobs; i++) {
      check_iter_entry(iter.get(), keys[i], write_timestamps[1],
                       blobs[i] + std::to_string(1), /*key_is_internal*/ false);
      iter->Next();
    }
  }

  // Forward iteration, then reverse to backward.
  {
    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    iter->SeekToFirst();
    for (int i = 0; i < num_blobs * 2 - 1; i++) {
      if (i < num_blobs) {
        check_iter_entry(iter.get(), keys[i], write_timestamps[1],
                         blobs[i] + std::to_string(1),
                         /*key_is_internal*/ false);
        if (i != num_blobs - 1) {
          iter->Next();
        }
      } else {
        if (i != num_blobs) {
          check_iter_entry(iter.get(), keys[num_blobs * 2 - 1 - i],
                           write_timestamps[1],
                           blobs[num_blobs * 2 - 1 - i] + std::to_string(1),
                           /*key_is_internal*/ false);
        }
        iter->Prev();
      }
    }
  }

  // Backward iterating one versions of each key, get in this order:
  // [("key4", Timestamp(2, 0), "blob41"),
  //  ("key3", Timestamp(2, 0), "blob31")...]
  {
    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    iter->SeekToLast();
    for (int i = 0; i < num_blobs; i++) {
      check_iter_entry(iter.get(), keys[num_blobs - 1 - i], write_timestamps[1],
                       blobs[num_blobs - 1 - i] + std::to_string(1),
                       /*key_is_internal*/ false);
      iter->Prev();
    }
    ASSERT_OK(iter->status());
  }

  // Backward iteration, then reverse to forward.
  {
    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    iter->SeekToLast();
    for (int i = 0; i < num_blobs * 2 - 1; i++) {
      if (i < num_blobs) {
        check_iter_entry(iter.get(), keys[num_blobs - 1 - i],
                         write_timestamps[1],
                         blobs[num_blobs - 1 - i] + std::to_string(1),
                         /*key_is_internal*/ false);
        if (i != num_blobs - 1) {
          iter->Prev();
        }
      } else {
        if (i != num_blobs) {
          check_iter_entry(iter.get(), keys[i - num_blobs], write_timestamps[1],
                           blobs[i - num_blobs] + std::to_string(1),
                           /*key_is_internal*/ false);
        }
        iter->Next();
      }
    }
  }

  Slice ts_lower_bound(read_timestamps[0]);
  read_options.iter_start_ts = &ts_lower_bound;
  // Forward iterating multiple versions of the same key, get in this order:
  // [("key0", Timestamp(2, 0), "blob01"),
  //  ("key0", Timestamp(1, 0), "blob00"),
  //  ("key1", Timestamp(2, 0), "blob11")...]
  {
    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    iter->SeekToFirst();
    for (int i = 0; i < num_blobs; i++) {
      for (size_t j = write_timestamps.size(); j > 0; --j) {
        check_iter_entry(iter.get(), keys[i], write_timestamps[j - 1],
                         blobs[i] + std::to_string(j - 1));
        iter->Next();
      }
    }
    ASSERT_OK(iter->status());
  }

  // Backward iterating multiple versions of the same key, get in this order:
  // [("key4", Timestamp(1, 0), "blob00"),
  //  ("key4", Timestamp(2, 0), "blob01"),
  //  ("key3", Timestamp(1, 0), "blob10")...]
  {
    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    iter->SeekToLast();
    for (int i = num_blobs; i > 0; i--) {
      for (size_t j = 0; j < write_timestamps.size(); j++) {
        check_iter_entry(iter.get(), keys[i - 1], write_timestamps[j],
                         blobs[i - 1] + std::to_string(j));
        iter->Prev();
      }
    }
    ASSERT_OK(iter->status());
  }

  int upper_bound_idx = num_blobs - 2;
  int lower_bound_idx = 1;
  Slice upper_bound_slice(keys[upper_bound_idx]);
  Slice lower_bound_slice(keys[lower_bound_idx]);
  read_options.iterate_upper_bound = &upper_bound_slice;
  read_options.iterate_lower_bound = &lower_bound_slice;

  // Forward iteration with upper and lower bound.
  {
    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    iter->SeekToFirst();
    for (int i = lower_bound_idx; i < upper_bound_idx; i++) {
      for (size_t j = write_timestamps.size(); j > 0; --j) {
        check_iter_entry(iter.get(), keys[i], write_timestamps[j - 1],
                         blobs[i] + std::to_string(j - 1));
        iter->Next();
      }
    }
    ASSERT_OK(iter->status());
  }

  // Backward iteration with upper and lower bound.
  {
    std::unique_ptr<Iterator> iter(db_->NewIterator(read_options));
    ASSERT_OK(iter->status());

    iter->SeekToLast();
    for (int i = upper_bound_idx; i > lower_bound_idx; i--) {
      for (size_t j = 0; j < write_timestamps.size(); j++) {
        check_iter_entry(iter.get(), keys[i - 1], write_timestamps[j],
                         blobs[i - 1] + std::to_string(j));
        iter->Prev();
      }
    }
    ASSERT_OK(iter->status());
  }
}

}  // namespace ROCKSDB_NAMESPACE

int main(int argc, char** argv) {
  ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();
  ::testing::InitGoogleTest(&argc, argv);
  RegisterCustomObjects(argc, argv);
  return RUN_ALL_TESTS();
}