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diff --git a/src/rocksdb/utilities/blob_db/blob_log_writer.h b/src/rocksdb/utilities/blob_db/blob_log_writer.h
new file mode 100644
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+++ b/src/rocksdb/utilities/blob_db/blob_log_writer.h
@@ -0,0 +1,94 @@
+//  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).
+#pragma once
+
+#ifndef ROCKSDB_LITE
+
+#include <cstdint>
+#include <memory>
+#include <string>
+
+#include "rocksdb/env.h"
+#include "rocksdb/slice.h"
+#include "rocksdb/statistics.h"
+#include "rocksdb/status.h"
+#include "rocksdb/types.h"
+#include "utilities/blob_db/blob_log_format.h"
+
+namespace ROCKSDB_NAMESPACE {
+
+class WritableFileWriter;
+
+namespace blob_db {
+
+/**
+ * Writer is the blob log stream writer. It provides an append-only
+ * abstraction for writing blob data.
+ *
+ *
+ * Look at blob_db_format.h to see the details of the record formats.
+ */
+
+class Writer {
+ public:
+  // Create a writer that will append data to "*dest".
+  // "*dest" must be initially empty.
+  // "*dest" must remain live while this Writer is in use.
+  Writer(std::unique_ptr<WritableFileWriter>&& dest, Env* env,
+         Statistics* statistics, uint64_t log_number, uint64_t bpsync,
+         bool use_fsync, uint64_t boffset = 0);
+  // No copying allowed
+  Writer(const Writer&) = delete;
+  Writer& operator=(const Writer&) = delete;
+
+  ~Writer() = default;
+
+  static void ConstructBlobHeader(std::string* buf, const Slice& key,
+                                  const Slice& val, uint64_t expiration);
+
+  Status AddRecord(const Slice& key, const Slice& val, uint64_t* key_offset,
+                   uint64_t* blob_offset);
+
+  Status AddRecord(const Slice& key, const Slice& val, uint64_t expiration,
+                   uint64_t* key_offset, uint64_t* blob_offset);
+
+  Status EmitPhysicalRecord(const std::string& headerbuf, const Slice& key,
+                            const Slice& val, uint64_t* key_offset,
+                            uint64_t* blob_offset);
+
+  Status AppendFooter(BlobLogFooter& footer);
+
+  Status WriteHeader(BlobLogHeader& header);
+
+  WritableFileWriter* file() { return dest_.get(); }
+
+  const WritableFileWriter* file() const { return dest_.get(); }
+
+  uint64_t get_log_number() const { return log_number_; }
+
+  bool ShouldSync() const { return block_offset_ > next_sync_offset_; }
+
+  Status Sync();
+
+  void ResetSyncPointer() { next_sync_offset_ += bytes_per_sync_; }
+
+ private:
+  std::unique_ptr<WritableFileWriter> dest_;
+  Env* env_;
+  Statistics* statistics_;
+  uint64_t log_number_;
+  uint64_t block_offset_;  // Current offset in block
+  uint64_t bytes_per_sync_;
+  uint64_t next_sync_offset_;
+  bool use_fsync_;
+
+ public:
+  enum ElemType { kEtNone, kEtFileHdr, kEtRecord, kEtFileFooter };
+  ElemType last_elem_type_;
+};
+
+}  // namespace blob_db
+}  // namespace ROCKSDB_NAMESPACE
+#endif  // ROCKSDB_LITE