YugabyteDB (2.13.1.0-b60, 21121d69985fbf76aa6958d8f04a9bfa936293b5)

//  Copyright (c) 2011-present, 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.

//

// The following only applies to changes made to this file as part of YugaByte development.

//

// Portions Copyright (c) YugaByte, Inc.

//

// Licensed 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.

//

#pragma once

#ifndef ROCKSDB_LITE

#include <string>

#include <vector>

#include "yb/rocksdb/utilities/stackable_db.h"

#include "yb/rocksdb/db.h"

namespace rocksdb {

// Database with TTL support.

//

// USE-CASES:

// This API should be used to open the db when key-values inserted are

//  meant to be removed from the db in a non-strict 'ttl' amount of time

//  Therefore, this guarantees that key-values inserted will remain in the

//  db for >= ttl amount of time and the db will make efforts to remove the

//  key-values as soon as possible after ttl seconds of their insertion.

//

// BEHAVIOUR:

// TTL is accepted in seconds

// (int32_t)Timestamp(creation) is suffixed to values in Put internally

// Expired TTL values deleted in compaction only:(Timestamp+ttl<time_now)

// Get/Iterator may return expired entries(compaction not run on them yet)

// Different TTL may be used during different Opens

// Example: Open1 at t=0 with ttl=4 and insert k1,k2, close at t=2

//          Open2 at t=3 with ttl=5. Now k1,k2 should be deleted at t>=5

// read_only=true opens in the usual read-only mode. Compactions will not be

//  triggered(neither manual nor automatic), so no expired entries removed

//

// CONSTRAINTS:

// Not specifying/passing or non-positive TTL behaves like TTL = infinity

//

// !!!WARNING!!!:

// Calling DB::Open directly to re-open a db created by this API will get

//  corrupt values(timestamp suffixed) and no ttl effect will be there

//  during the second Open, so use this API consistently to open the db

// Be careful when passing ttl with a small positive value because the

//  whole database may be deleted in a small amount of time

class DBWithTTL : public StackableDB {

 public:

  virtual Status CreateColumnFamilyWithTtl(

      const ColumnFamilyOptions& options, const std::string& column_family_name,

      ColumnFamilyHandle** handle, int ttl) = 0;

  static Status Open(const Options& options, const std::string& dbname,

                     DBWithTTL** dbptr, int32_t ttl = 0,

                     bool read_only = false);

  static Status Open(const DBOptions& db_options, const std::string& dbname,

                     const std::vector<ColumnFamilyDescriptor>& column_families,

                     std::vector<ColumnFamilyHandle*>* handles,

                     DBWithTTL** dbptr, std::vector<int32_t> ttls,

                     bool read_only = false);

 protected:

  explicit DBWithTTL(DB* db) : StackableDB(db) {}

};

}  // namespace rocksdb

#endif  // ROCKSDB_LITE