YugabyteDB (2.13.0.0-b42, bfc6a6643e7399ac8a0e81d06a3ee6d6571b33ab)

// 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.

//

#include "yb/docdb/doc_ttl_util.h"

#include "yb/common/schema.h"

#include "yb/docdb/value.h"

#include "yb/server/hybrid_clock.h"

#include "yb/util/monotime.h"

using std::string;

using yb::HybridTime;

namespace yb {

namespace docdb {

bool HasExpiredTTL(const HybridTime& key_hybrid_time, const MonoDelta &ttl,

                   const HybridTime& read_hybrid_time) {

  if (ttl.Equals(Value::kMaxTtl) || ttl.Equals(Value::kResetTtl)) {

    return false;

  }

  return server::HybridClock::CompareHybridClocksToDelta(

      key_hybrid_time, read_hybrid_time, ttl) > 0;

}

bool HasExpiredTTL(const HybridTime& expiration_time, const HybridTime& read_hybrid_time) {

  if (expiration_time == kNoExpiration || expiration_time == kUseDefaultTTL) {

    return false;

  }

  return expiration_time < read_hybrid_time;

}

const MonoDelta TableTTL(const Schema& schema) {

  // In this context, a ttl of kMaxTtl indicates that the table has no default TTL.

  MonoDelta ttl = Value::kMaxTtl;

  if (schema.table_properties().HasDefaultTimeToLive()) {

    uint64_t default_ttl = schema.table_properties().DefaultTimeToLive();

    return default_ttl == kResetTTL ? Value::kMaxTtl : MonoDelta::FromMilliseconds(default_ttl);

  }

  return ttl;

}

const MonoDelta ComputeTTL(const MonoDelta& value_ttl, const MonoDelta& default_ttl) {

  MonoDelta ttl;

  // When encoded with a value, kMaxTtl indicates that table TTL should be used.

  // If not kMaxTtl, then there is a value-level TTL that we should use instead.

  // A value of kResetTTL (i.e. 0) indicates the value should not expire, in which

  // case kMaxTtl (now representing no expiration) is returned.

  if (!value_ttl.Equals(Value::kMaxTtl)) {

    ttl = value_ttl.ToMilliseconds() == kResetTTL ? Value::kMaxTtl : value_ttl;

  } else {

    ttl = default_ttl;

  }

  return ttl;

}

const MonoDelta ComputeTTL(const MonoDelta& value_ttl, const Schema& schema) {

  return ComputeTTL(value_ttl, TableTTL(schema));

}

const HybridTime FileExpirationFromValueTTL(

    const HybridTime& key_hybrid_time, const MonoDelta& value_ttl) {

  if (value_ttl.Equals(Value::kMaxTtl)) {

    return kUseDefaultTTL;

  } else if (value_ttl.Equals(Value::kResetTtl)) {

    return kNoExpiration;

  }

  auto exp_time = server::HybridClock::AddPhysicalTimeToHybridTime(key_hybrid_time, value_ttl);

  // Sanity check for overflow, return no expiration if detected.

  if (server::HybridClock::CompareHybridClocksToDelta(

      key_hybrid_time, exp_time, value_ttl) != 0) {

    return kNoExpiration;

  }

  return exp_time;

}

const HybridTime MaxExpirationFromValueAndTableTTL(const HybridTime& key_hybrid_time,

    const MonoDelta& table_ttl, const HybridTime& value_expiry) {

  // If the max expiration time of values requires the file never expire,

  // then don't expire the file no matter what.

  if (value_expiry == kNoExpiration || key_hybrid_time.is_special()) {

    return kNoExpiration;

  }

  // If the table TTL indicates no expiration, then defer to the value expiration.

  // If the value expiration also indicates to use the table TTL, don't expire the file.

  if (table_ttl.Equals(Value::kMaxTtl)) {

    return value_expiry == kUseDefaultTTL ? kNoExpiration : value_expiry;

  }

  // Calculate the expiration time based on table TTL only.

  auto table_expiry = server::HybridClock::AddPhysicalTimeToHybridTime(key_hybrid_time, table_ttl);

  // Sanity check for overflow, return no expiration if overflow detected.

  if (server::HybridClock::CompareHybridClocksToDelta(

      key_hybrid_time, table_expiry, table_ttl) != 0) {

    return kNoExpiration;

  }

  // Return the greater of the table expiration time and the value expiration time.

  return value_expiry >= table_expiry ? value_expiry : table_expiry;

}

}  // namespace docdb

}  // namespace yb