rocksdb/db/filename.h
Yueh-Hsuan Chiang 28c82ff1b3 CompactFiles, EventListener and GetDatabaseMetaData
Summary:
This diff adds three sets of APIs to RocksDB.

= GetColumnFamilyMetaData =
* This APIs allow users to obtain the current state of a RocksDB instance on one column family.
* See GetColumnFamilyMetaData in include/rocksdb/db.h

= EventListener =
* A virtual class that allows users to implement a set of
  call-back functions which will be called when specific
  events of a RocksDB instance happens.
* To register EventListener, simply insert an EventListener to ColumnFamilyOptions::listeners

= CompactFiles =
* CompactFiles API inputs a set of file numbers and an output level, and RocksDB
  will try to compact those files into the specified level.

= Example =
* Example code can be found in example/compact_files_example.cc, which implements
  a simple external compactor using EventListener, GetColumnFamilyMetaData, and
  CompactFiles API.

Test Plan:
listener_test
compactor_test
example/compact_files_example
export ROCKSDB_TESTS=CompactFiles
db_test
export ROCKSDB_TESTS=MetaData
db_test

Reviewers: ljin, igor, rven, sdong

Reviewed By: sdong

Subscribers: MarkCallaghan, dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D24705
2014-11-07 14:45:18 -08:00

139 lines
5.3 KiB
C++

// Copyright (c) 2013, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
//
// File names used by DB code
#pragma once
#include <stdint.h>
#include <unordered_map>
#include <string>
#include <vector>
#include "rocksdb/slice.h"
#include "rocksdb/status.h"
#include "rocksdb/transaction_log.h"
#include "port/port.h"
namespace rocksdb {
class Env;
class Directory;
enum FileType {
kLogFile,
kDBLockFile,
kTableFile,
kDescriptorFile,
kCurrentFile,
kTempFile,
kInfoLogFile, // Either the current one, or an old one
kMetaDatabase,
kIdentityFile
};
// Return the name of the log file with the specified number
// in the db named by "dbname". The result will be prefixed with
// "dbname".
extern std::string LogFileName(const std::string& dbname, uint64_t number);
static const std::string ARCHIVAL_DIR = "archive";
extern std::string ArchivalDirectory(const std::string& dbname);
// Return the name of the archived log file with the specified number
// in the db named by "dbname". The result will be prefixed with "dbname".
extern std::string ArchivedLogFileName(const std::string& dbname,
uint64_t num);
extern std::string MakeTableFileName(const std::string& name, uint64_t number);
// the reverse function of MakeTableFileName
// TODO(yhchiang): could merge this function with ParseFileName()
extern uint64_t TableFileNameToNumber(const std::string& name);
// Return the name of the sstable with the specified number
// in the db named by "dbname". The result will be prefixed with
// "dbname".
extern std::string TableFileName(const std::vector<DbPath>& db_paths,
uint64_t number, uint32_t path_id);
// Sufficient buffer size for FormatFileNumber.
extern const size_t kFormatFileNumberBufSize;
extern void FormatFileNumber(uint64_t number, uint32_t path_id, char* out_buf,
size_t out_buf_size);
// Return the name of the descriptor file for the db named by
// "dbname" and the specified incarnation number. The result will be
// prefixed with "dbname".
extern std::string DescriptorFileName(const std::string& dbname,
uint64_t number);
// Return the name of the current file. This file contains the name
// of the current manifest file. The result will be prefixed with
// "dbname".
extern std::string CurrentFileName(const std::string& dbname);
// Return the name of the lock file for the db named by
// "dbname". The result will be prefixed with "dbname".
extern std::string LockFileName(const std::string& dbname);
// Return the name of a temporary file owned by the db named "dbname".
// The result will be prefixed with "dbname".
extern std::string TempFileName(const std::string& dbname, uint64_t number);
// A helper structure for prefix of info log names.
struct InfoLogPrefix {
char buf[260];
Slice prefix;
// Prefix with DB absolute path encoded
explicit InfoLogPrefix(bool has_log_dir, const std::string& db_absolute_path);
// Default Prefix
explicit InfoLogPrefix();
};
// Return the name of the info log file for "dbname".
extern std::string InfoLogFileName(const std::string& dbname,
const std::string& db_path="", const std::string& log_dir="");
// Return the name of the old info log file for "dbname".
extern std::string OldInfoLogFileName(const std::string& dbname, uint64_t ts,
const std::string& db_path="", const std::string& log_dir="");
// Return the name to use for a metadatabase. The result will be prefixed with
// "dbname".
extern std::string MetaDatabaseName(const std::string& dbname,
uint64_t number);
// Return the name of the Identity file which stores a unique number for the db
// that will get regenerated if the db loses all its data and is recreated fresh
// either from a backup-image or empty
extern std::string IdentityFileName(const std::string& dbname);
// If filename is a rocksdb file, store the type of the file in *type.
// The number encoded in the filename is stored in *number. If the
// filename was successfully parsed, returns true. Else return false.
// info_log_name_prefix is the path of info logs.
extern bool ParseFileName(const std::string& filename, uint64_t* number,
const Slice& info_log_name_prefix, FileType* type,
WalFileType* log_type = nullptr);
// Same as previous function, but skip info log files.
extern bool ParseFileName(const std::string& filename, uint64_t* number,
FileType* type, WalFileType* log_type = nullptr);
// Make the CURRENT file point to the descriptor file with the
// specified number.
extern Status SetCurrentFile(Env* env, const std::string& dbname,
uint64_t descriptor_number,
Directory* directory_to_fsync);
// Make the IDENTITY file for the db
extern Status SetIdentityFile(Env* env, const std::string& dbname);
} // namespace rocksdb