ClickHouse/src/Backups/BackupEntryFromAppendOnlyFile.h

36 lines
1.2 KiB
C++

#pragma once
#include <Backups/BackupEntryFromImmutableFile.h>
namespace DB
{
/// Represents a file prepared to be included in a backup, assuming that until this backup entry is destroyed
/// the file can be appended with new data, but the bytes which are already in the file won't be changed.
class BackupEntryFromAppendOnlyFile : public BackupEntryFromImmutableFile
{
public:
/// The constructor is allowed to not set `file_size_` or `checksum_`, in that case it will be calculated from the data.
explicit BackupEntryFromAppendOnlyFile(
const String & file_path_,
const std::optional<UInt64> & file_size_ = {},
const std::optional<UInt128> & checksum_ = {},
const std::shared_ptr<Poco::TemporaryFile> & temporary_file_ = {});
BackupEntryFromAppendOnlyFile(
const DiskPtr & disk_,
const String & file_path_,
const std::optional<UInt64> & file_size_ = {},
const std::optional<UInt128> & checksum_ = {},
const std::shared_ptr<TemporaryFileOnDisk> & temporary_file_ = {});
UInt64 getSize() const override { return limit; }
std::unique_ptr<SeekableReadBuffer> getReadBuffer() const override;
private:
const UInt64 limit;
};
}