Grcov report - time.rs

1

use std::borrow::Cow;

2

use std::fmt::Debug;

3

use std::time::{Duration, SystemTime, UNIX_EPOCH};

4

5

use ordered_varint::Variable;

6

use serde::{Deserialize, Serialize};

7

8

use crate::key::time::limited::{BonsaiEpoch, UnixEpoch};

9

use crate::key::{ByteSource, CompositeKind, Key, KeyEncoding, KeyKind, KeyVisitor};

10

11

impl<'k> Key<'k> for Duration {

12

    const CAN_OWN_BYTES: bool = false;

13

14

4

    fn from_ord_bytes<'e>(bytes: ByteSource<'k, 'e>) -> Result<Self, Self::Error> {

15

4

        let merged = u128::decode_variable(bytes.as_ref()).map_err(|_| TimeError::InvalidValue)?;

16

4

        let seconds = u64::try_from(merged >> 30).map_err(|_| TimeError::DeltaNotRepresentable)?;

17

4

        let nanos = u32::try_from(merged & (2_u128.pow(30) - 1)).unwrap();

18

4

        Ok(Self::new(seconds, nanos))

19

4

20

21

22

impl KeyEncoding<Self> for Duration {

23

    type Error = TimeError;

24

25

    const LENGTH: Option<usize> = None;

26

27

    fn describe<Visitor>(visitor: &mut Visitor)

28

    where

29

        Visitor: KeyVisitor,

30

31

        visitor.visit_composite(

32

            CompositeKind::Struct(Cow::Borrowed("std::time::Duration")),

33

1,

34

);

35

        visitor.visit_type(KeyKind::Unsigned);

36

37

38

4

    fn as_ord_bytes(&self) -> Result<Cow<'_, [u8]>, Self::Error> {

39

4

        let merged = u128::from(self.as_secs()) << 30 | u128::from(self.subsec_nanos());

40

4

        // It's safe to unwrap here, because under the hood ordered-varint can

41

4

        // only raise an error if the top bits are set. Since we only ever add

42

4

        // 94 bits, the top bits will not have any data set.

43

4

        Ok(Cow::Owned(merged.to_variable_vec().unwrap()))

44

4

45

46

47

1

#[test]

48

1

fn duration_key_tests() {

49

1

    assert_eq!(

50

1

        Duration::ZERO,

51

1

        Duration::from_ord_bytes(ByteSource::Borrowed(

52

1

            &Duration::ZERO.as_ord_bytes().unwrap()

53

1

))

54

1

        .unwrap()

55

1

);

56

1

    assert_eq!(

57

1

        Duration::MAX,

58

1

        Duration::from_ord_bytes(ByteSource::Borrowed(&Duration::MAX.as_ord_bytes().unwrap()))

59

1

            .unwrap()

60

1

);

61

1

62

63

impl<'k> Key<'k> for SystemTime {

64

    const CAN_OWN_BYTES: bool = false;

65

66

2

    fn from_ord_bytes<'e>(bytes: ByteSource<'k, 'e>) -> Result<Self, Self::Error> {

67

2

        let since_epoch = Duration::from_ord_bytes(bytes)?;

68

2

        UNIX_EPOCH

69

2

            .checked_add(since_epoch)

70

2

            .ok_or(TimeError::DeltaNotRepresentable)

71

2

72

73

74

impl KeyEncoding<Self> for SystemTime {

75

    type Error = TimeError;

76

77

    const LENGTH: Option<usize> = None;

78

79

    fn describe<Visitor>(visitor: &mut Visitor)

80

    where

81

        Visitor: KeyVisitor,

82

83

        visitor.visit_composite(

84

            CompositeKind::Struct(Cow::Borrowed("std::time::SystemTime")),

85

1,

86

);

87

        visitor.visit_type(KeyKind::Unsigned);

88

89

90

2

    fn as_ord_bytes(&self) -> Result<Cow<'_, [u8]>, Self::Error> {

91

2

        let since_epoch = self.duration_since(UNIX_EPOCH).unwrap();

92

2

        match since_epoch.as_ord_bytes()? {

93

2

            Cow::Owned(bytes) => Ok(Cow::Owned(bytes)),

94

            Cow::Borrowed(_) => unreachable!(),

95

96

2

97

98

99

1

#[test]

100

1

fn system_time_tests() {

101

1

    assert_eq!(

102

1

        UNIX_EPOCH,

103

1

        SystemTime::from_ord_bytes(ByteSource::Borrowed(&UNIX_EPOCH.as_ord_bytes().unwrap()))

104

1

            .unwrap()

105

1

);

106

1

    let now = SystemTime::now();

107

1

    assert_eq!(

108

1

        now,

109

1

        SystemTime::from_ord_bytes(ByteSource::Borrowed(&now.as_ord_bytes().unwrap())).unwrap()

110

1

);

111

1

112

113

/// An error that indicates that the stored timestamp is unable to be converted

114

/// to the destination type without losing data.

115

#[derive(thiserror::Error, Debug)]

116

#[error("the stored timestamp is outside the allowed range")]

117

pub struct DeltaNotRepresentable;

118

119

/// Errors that can arise from parsing times serialized with [`Key`].

120

#[derive(thiserror::Error, Debug, Clone, Serialize, Deserialize)]

121

pub enum TimeError {

122

    /// An error that indicates that the stored timestamp is unable to be converted

123

    /// to the destination type without losing data.

124

    #[error("the stored timestamp is outside the allowed range")]

125

    DeltaNotRepresentable,

126

    /// The value stored was not encoded correctly.

127

    #[error("invalid value")]

128

    InvalidValue,

129

130

131

impl From<DeltaNotRepresentable> for TimeError {

132

    fn from(_: DeltaNotRepresentable) -> Self {

133

        Self::DeltaNotRepresentable

134

135

136

137

impl From<std::io::Error> for TimeError {

138

    fn from(_: std::io::Error) -> Self {

139

        Self::InvalidValue

140

141

142

143

/// Types for storing limited-precision Durations.

144

pub mod limited {

145

    use std::borrow::Cow;

146

    use std::fmt::{self, Debug, Display, Write};

147

    use std::hash::Hash;

148

    use std::iter;

149

    use std::marker::PhantomData;

150

    use std::str::FromStr;

151

    use std::time::{Duration, SystemTime, UNIX_EPOCH};

152

153

    use derive_where::derive_where;

154

    use ordered_varint::Variable;

155

    use serde::{Deserialize, Serialize};

156

157

    use crate::key::time::TimeError;

158

    use crate::key::{ByteSource, CompositeKind, Key, KeyEncoding, KeyVisitor};

159

160

    /// A [`Duration`] of time stored with a limited `Resolution`. This type may be

161

    /// preferred to [`std::time::Duration`] because `Duration` takes a full 12

162

    /// bytes to achieve its nanosecond resolution.

163

///

164

    /// Converting from [`Duration`] truncates the duration and performs no rounding.

165

///

166

    /// The `Resolution` type controls the storage size. The resolutions

167

    /// provided by BonsaiDb:

168

///

169

    /// - [`Weeks`]

170

    /// - [`Days`]

171

    /// - [`Hours`]

172

    /// - [`Minutes`]

173

    /// - [`Seconds`]

174

    /// - [`Milliseconds`]

175

    /// - [`Microseconds`]

176

    /// - [`Nanoseconds`]

177

///

178

    /// Other resolutions can be used by implementing [`TimeResolution`].

179

210

    #[derive_where(Hash, Eq, PartialEq, Ord, PartialOrd, Clone, Copy)]

180

    pub struct LimitedResolutionDuration<Resolution: TimeResolution> {

181

        representation: Resolution::Representation,

182

        _resolution: PhantomData<Resolution>,

183

184

185

    /// A resolution of a time measurement.

186

    pub trait TimeResolution: Debug + Send + Sync {

187

        /// The in-memory and serialized representation for this resolution.

188

        type Representation: Variable

189

            + Serialize

190

            + for<'de> Deserialize<'de>

191

            + for<'k> Key<'k>

192

            + Display

193

            + Hash

194

            + Eq

195

            + PartialEq

196

            + Ord

197

            + PartialOrd

198

            + Clone

199

            + Copy

200

            + Send

201

            + Sync

202

            + Debug

203

            + Default;

204

205

        /// The label used when formatting times with this resolution.

206

        const FORMAT_SUFFIX: &'static str;

207

208

        /// Converts a [`Self::Representation`] to [`Duration`].

209

        fn repr_to_duration(value: Self::Representation) -> Result<SignedDuration, TimeError>;

210

211

        /// Converts a [`Duration`] to [`Self::Representation`].

212

        fn duration_to_repr(duration: SignedDuration) -> Result<Self::Representation, TimeError>;

213

214

215

    /// A [`Duration`] that can be either negative or positive.

216

    #[derive(Copy, Clone, Debug, Eq, PartialEq)]

217

    pub enum SignedDuration {

218

        /// A duration representing a positive measurement of time.

219

        Positive(Duration),

220

        /// A duration representing a negative measurement of time.

221

        Negative(Duration),

222

223

224

    impl SignedDuration {

225

        /// Adds the two durations, honoring the signs, and returns the result

226

        /// if the duration is representable.

227

        #[must_use]

228

9

        pub fn checked_add(self, other: Self) -> Option<Self> {

229

9

            match (self, other) {

230

6

                (SignedDuration::Positive(a), SignedDuration::Positive(b)) => {

231

6

                    a.checked_add(b).map(SignedDuration::Positive)

232

233

1

                (SignedDuration::Negative(a), SignedDuration::Negative(b)) => {

234

1

                    a.checked_add(b).map(SignedDuration::Negative)

235

236

1

                (SignedDuration::Positive(a), SignedDuration::Negative(b)) => {

237

1

                    if let Some(result) = a.checked_sub(b) {

238

                        Some(SignedDuration::Positive(result))

239

                    } else {

240

1

                        Some(SignedDuration::Negative(b - a))

241

242

243

1

                (SignedDuration::Negative(a), SignedDuration::Positive(b)) => {

244

1

                    if let Some(result) = a.checked_sub(b) {

245

1

                        Some(SignedDuration::Negative(result))

246

                    } else {

247

                        Some(SignedDuration::Positive(b - a))

248

249

250

251

9

252

253

254

    impl<Resolution> LimitedResolutionDuration<Resolution>

255

    where

256

        Resolution: TimeResolution,

257

258

        /// Returns a new instance with the `representation` provided, which

259

        /// conceptually is a unit of `Resolution`.

260

22872

        pub const fn new(representation: Resolution::Representation) -> Self {

261

22872

            Self {

262

22872

                representation,

263

22872

                _resolution: PhantomData,

264

22872

265

22872

266

267

        /// Returns the internal representation of this duration.

268

6240

        pub const fn representation(&self) -> Resolution::Representation {

269

6240

            self.representation

270

6240

271

272

273

    impl<Resolution: TimeResolution> Debug for LimitedResolutionDuration<Resolution> {

274

14

        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {

275

14

            write!(f, "{:?}{}", self.representation, Resolution::FORMAT_SUFFIX)

276

14

277

278

279

    impl<Resolution: TimeResolution> Display for LimitedResolutionDuration<Resolution> {

280

        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {

281

            write!(f, "{}{}", self.representation, Resolution::FORMAT_SUFFIX)

282

283

284

285

    impl iter::Sum<SignedDuration> for Option<SignedDuration> {

286

        fn sum<I: Iterator<Item = SignedDuration>>(mut iter: I) -> Self {

287

            let first = iter.next();

288

            iter.fold(first, |sum, duration| {

289

                sum.and_then(|sum| sum.checked_add(duration))

290

})

291

292

293

294

    impl iter::Sum<Self> for SignedDuration {

295

        fn sum<I: Iterator<Item = Self>>(iter: I) -> Self {

296

            iter.sum::<Option<Self>>().expect("operation overflowed")

297

298

299

300

    impl<'k, Resolution> Key<'k> for LimitedResolutionDuration<Resolution>

301

    where

302

        Resolution: TimeResolution,

303

304

        const CAN_OWN_BYTES: bool = false;

305

306

14

        fn from_ord_bytes<'e>(bytes: ByteSource<'k, 'e>) -> Result<Self, Self::Error> {

307

14

            let representation =

308

14

                <Resolution::Representation as Variable>::decode_variable(bytes.as_ref())

309

14

                    .map_err(|_| TimeError::InvalidValue)?;

310

311

14

            Ok(Self {

312

14

                representation,

313

14

                _resolution: PhantomData,

314

14

})

315

14

316

317

318

    impl<Resolution> KeyEncoding<Self> for LimitedResolutionDuration<Resolution>

319

    where

320

        Resolution: TimeResolution,

321

322

        type Error = TimeError;

323

324

        const LENGTH: Option<usize> = None;

325

326

        fn describe<Visitor>(visitor: &mut Visitor)

327

        where

328

            Visitor: KeyVisitor,

329

330

            visitor.visit_composite(

331

                CompositeKind::Struct(Cow::Borrowed(

332

                    "bonsaidb::core::key::time::LimitedResolutionDuration",

333

)),

334

1,

335

);

336

            <Resolution::Representation as KeyEncoding>::describe(visitor);

337

338

339

14

        fn as_ord_bytes(&self) -> Result<Cow<'_, [u8]>, Self::Error> {

340

14

            self.representation

341

14

                .to_variable_vec()

342

14

                .map(Cow::Owned)

343

14

                .map_err(|_| TimeError::InvalidValue)

344

14

345

346

347

    impl<Resolution> Default for LimitedResolutionDuration<Resolution>

348

    where

349

        Resolution: TimeResolution,

350

351

        fn default() -> Self {

352

            Self {

353

                representation: <Resolution::Representation as Default>::default(),

354

                _resolution: PhantomData,

355

356

357

358

359

    impl<Resolution> Serialize for LimitedResolutionDuration<Resolution>

360

    where

361

        Resolution: TimeResolution,

362

363

764

        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>

364

764

        where

365

764

            S: serde::Serializer,

366

764

367

764

            self.representation.serialize(serializer)

368

764

369

370

371

    impl<'de, Resolution> Deserialize<'de> for LimitedResolutionDuration<Resolution>

372

    where

373

        Resolution: TimeResolution,

374

375

18564

        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

376

18564

        where

377

18564

            D: serde::Deserializer<'de>,

378

18564

379

18564

            <Resolution::Representation as Deserialize<'de>>::deserialize(deserializer)

380

18564

                .map(Self::new)

381

18564

382

383

384

    impl<Resolution> TryFrom<SignedDuration> for LimitedResolutionDuration<Resolution>

385

    where

386

        Resolution: TimeResolution,

387

388

        type Error = TimeError;

389

390

4587

        fn try_from(duration: SignedDuration) -> Result<Self, Self::Error> {

391

4587

            Resolution::duration_to_repr(duration).map(|representation| Self {

392

4587

                representation,

393

4587

                _resolution: PhantomData,

394

4587

})

395

4587

396

397

398

    impl<Resolution> TryFrom<LimitedResolutionDuration<Resolution>> for SignedDuration

399

    where

400

        Resolution: TimeResolution,

401

402

        type Error = TimeError;

403

404

39

        fn try_from(value: LimitedResolutionDuration<Resolution>) -> Result<Self, Self::Error> {

405

39

            Resolution::repr_to_duration(value.representation)

406

39

407

408

409

    impl<Resolution> TryFrom<Duration> for LimitedResolutionDuration<Resolution>

410

    where

411

        Resolution: TimeResolution,

412

413

        type Error = TimeError;

414

415

21

        fn try_from(duration: Duration) -> Result<Self, Self::Error> {

416

21

            Self::try_from(SignedDuration::Positive(duration))

417

21

418

419

420

    impl<Resolution> TryFrom<LimitedResolutionDuration<Resolution>> for Duration

421

    where

422

        Resolution: TimeResolution,

423

424

        type Error = TimeError;

425

426

7

        fn try_from(value: LimitedResolutionDuration<Resolution>) -> Result<Self, Self::Error> {

427

7

            match SignedDuration::try_from(value) {

428

7

                Ok(SignedDuration::Positive(value)) => Ok(value),

429

                _ => Err(TimeError::DeltaNotRepresentable),

430

431

7

432

433

434

    impl<Resolution> iter::Sum<LimitedResolutionDuration<Resolution>>

435

        for Option<LimitedResolutionDuration<Resolution>>

436

    where

437

        Resolution: TimeResolution,

438

439

7

        fn sum<I: Iterator<Item = LimitedResolutionDuration<Resolution>>>(mut iter: I) -> Self {

440

7

            let first = iter

441

7

                .next()

442

7

                .and_then(|dur| Resolution::repr_to_duration(dur.representation).ok());

443

9

            let duration = iter.fold(first, |sum, dur| {

444

9

                sum.and_then(|sum| {

445

9

                    Resolution::repr_to_duration(dur.representation)

446

9

                        .ok()

447

9

                        .and_then(|dur| sum.checked_add(dur))

448

9

})

449

9

});

450

7

            duration.and_then(|dur| {

451

7

                Resolution::duration_to_repr(dur)

452

7

                    .ok()

453

7

                    .map(LimitedResolutionDuration::new)

454

7

})

455

7

456

457

458

    impl<Resolution> iter::Sum<Self> for LimitedResolutionDuration<Resolution>

459

    where

460

        Resolution: TimeResolution,

461

462

1

        fn sum<I: Iterator<Item = Self>>(iter: I) -> Self {

463

1

            iter.sum::<Option<Self>>().expect("operation overflowed")

464

1

465

466

467

1

    #[test]

468

1

    fn limited_resolution_duration_sum() {

469

1

        use super::Nanoseconds;

470

1

        assert_eq!(

471

1

472

1

                Nanoseconds::new(1),

473

1

                Nanoseconds::new(2),

474

1

                Nanoseconds::new(3),

475

1

476

1

            .into_iter()

477

1

            .sum::<Nanoseconds>(),

478

1

            Nanoseconds::new(6)

479

1

);

480

1

        assert_eq!(

481

1

482

1

                Nanoseconds::new(1),

483

1

                Nanoseconds::new(2),

484

1

                Nanoseconds::new(3),

485

1

486

1

            .into_iter()

487

1

            .sum::<Option<Nanoseconds>>(),

488

1

            Some(Nanoseconds::new(6))

489

1

);

490

491

1

        assert_eq!(

492

1

            [Nanoseconds::new(1), Nanoseconds::new(i64::MAX)]

493

1

                .into_iter()

494

1

                .sum::<Option<Nanoseconds>>(),

495

1

            None

496

1

);

497

498

1

        assert_eq!(

499

1

            [Nanoseconds::new(i64::MAX), Nanoseconds::new(1)]

500

1

                .into_iter()

501

1

                .sum::<Option<Nanoseconds>>(),

502

1

            None

503

1

);

504

505

1

        assert_eq!(

506

1

            [Nanoseconds::new(i64::MIN), Nanoseconds::new(-11)]

507

1

                .into_iter()

508

1

                .sum::<Option<Nanoseconds>>(),

509

1

            None

510

1

);

511

512

1

        assert_eq!(

513

1

            [Nanoseconds::new(1), Nanoseconds::new(i64::MIN)]

514

1

                .into_iter()

515

1

                .sum::<Option<Nanoseconds>>(),

516

1

            Some(Nanoseconds::new(i64::MIN + 1))

517

1

);

518

1

        assert_eq!(

519

1

            [Nanoseconds::new(i64::MIN), Nanoseconds::new(1)]

520

1

                .into_iter()

521

1

                .sum::<Option<Nanoseconds>>(),

522

1

            Some(Nanoseconds::new(i64::MIN + 1))

523

1

);

524

1

525

526

    /// A [`TimeResolution`] implementation that preserves nanosecond

527

    /// resolution. Internally, the number of microseconds is represented as an

528

    /// `i64`, allowing a range of +/- ~292.5 years.

529

    #[derive(Debug)]

530

    pub enum Nanoseconds {}

531

532

    const I64_MIN_ABS_AS_U64: u64 = 9_223_372_036_854_775_808;

533

534

    impl TimeResolution for Nanoseconds {

535

        type Representation = i64;

536

537

        const FORMAT_SUFFIX: &'static str = "ns";

538

539

4102

        fn repr_to_duration(value: Self::Representation) -> Result<SignedDuration, TimeError> {

540

4102

            if let Ok(unsigned) = u64::try_from(value) {

541

16

                Ok(SignedDuration::Positive(Duration::from_nanos(unsigned)))

542

            } else {

543

4086

                let positive = value

544

4086

                    .checked_abs()

545

4086

                    .and_then(|value| u64::try_from(value).ok())

546

4086

                    .unwrap_or(I64_MIN_ABS_AS_U64);

547

4086

                Ok(SignedDuration::Negative(Duration::from_nanos(positive)))

548

549

4102

550

551

4498

        fn duration_to_repr(duration: SignedDuration) -> Result<Self::Representation, TimeError> {

552

4498

            match duration {

553

10

                SignedDuration::Positive(duration) => {

554

10

                    i64::try_from(duration.as_nanos()).map_err(|_| TimeError::DeltaNotRepresentable)

555

556

4488

                SignedDuration::Negative(duration) => {

557

4488

                    let nanos = duration.as_nanos();

558

4488

                    if let Ok(nanos) = i64::try_from(nanos) {

559

4487

                        Ok(-nanos)

560

1

                    } else if nanos == u128::from(I64_MIN_ABS_AS_U64) {

561

                        Ok(i64::MIN)

562

                    } else {

563

1

                        Err(TimeError::DeltaNotRepresentable)

564

565

566

567

4498

568

569

570

    /// A [`TimeResolution`] implementation that truncates time measurements to

571

    /// microseconds. Internally, the number of microseconds is represented as

572

    /// an `i64`, allowing a range of +/- ~292,471 years.

573

    #[derive(Debug)]

574

    pub enum Microseconds {}

575

576

    impl TimeResolution for Microseconds {

577

        type Representation = i64;

578

579

        const FORMAT_SUFFIX: &'static str = "us";

580

581

7

        fn repr_to_duration(value: Self::Representation) -> Result<SignedDuration, TimeError> {

582

7

            if let Ok(unsigned) = u64::try_from(value) {

583

4

                Ok(SignedDuration::Positive(Duration::from_micros(unsigned)))

584

            } else {

585

3

                let positive = value

586

3

                    .checked_abs()

587

3

                    .and_then(|value| u64::try_from(value).ok())

588

3

                    .unwrap_or(u64::MAX);

589

3

                Ok(SignedDuration::Negative(Duration::from_micros(positive)))

590

591

7

592

593

14

        fn duration_to_repr(duration: SignedDuration) -> Result<Self::Representation, TimeError> {

594

14

            match duration {

595

7

                SignedDuration::Positive(duration) => i64::try_from(duration.as_micros())

596

7

                    .map_err(|_| TimeError::DeltaNotRepresentable),

597

7

                SignedDuration::Negative(duration) => {

598

7

                    let rounded_up = duration

599

7

                        .checked_add(Duration::from_nanos(999))

600

7

                        .ok_or(TimeError::DeltaNotRepresentable)?;

601

7

                    i64::try_from(rounded_up.as_micros())

602

7

                        .map(|repr| -repr)

603

7

                        .map_err(|_| TimeError::DeltaNotRepresentable)

604

605

606

14

607

608

609

    /// A [`TimeResolution`] implementation that truncates time measurements to

610

    /// milliseconds. Internally, the number of milliseconds is represented as

611

    /// an `i64`, allowing a range of +/- ~292.5 million years.

612

    #[derive(Debug)]

613

    pub enum Milliseconds {}

614

615

    impl TimeResolution for Milliseconds {

616

        type Representation = i64;

617

618

        const FORMAT_SUFFIX: &'static str = "ms";

619

620

7

        fn repr_to_duration(value: Self::Representation) -> Result<SignedDuration, TimeError> {

621

7

            if let Ok(unsigned) = u64::try_from(value) {

622

4

                Ok(SignedDuration::Positive(Duration::from_millis(unsigned)))

623

            } else {

624

3

                let positive = value

625

3

                    .checked_abs()

626

3

                    .and_then(|value| u64::try_from(value).ok())

627

3

                    .unwrap_or(u64::MAX);

628

3

                Ok(SignedDuration::Negative(Duration::from_millis(positive)))

629

630

7

631

632

14

        fn duration_to_repr(duration: SignedDuration) -> Result<Self::Representation, TimeError> {

633

14

            match duration {

634

7

                SignedDuration::Positive(duration) => i64::try_from(duration.as_millis())

635

7

                    .map_err(|_| TimeError::DeltaNotRepresentable),

636

7

                SignedDuration::Negative(duration) => {

637

7

                    let rounded_up = duration

638

7

                        .checked_add(Duration::from_nanos(999_999))

639

7

                        .ok_or(TimeError::DeltaNotRepresentable)?;

640

7

                    i64::try_from(rounded_up.as_millis())

641

7

                        .map(|repr| -repr)

642

7

                        .map_err(|_| TimeError::DeltaNotRepresentable)

643

644

645

14

646

647

648

    /// A [`TimeResolution`] implementation that truncates time measurements to

649

    /// seconds. Internally, the number of seconds is represented as an `i64`,

650

    /// allowing a range of +/- ~21 times the age of the universe.

651

    #[derive(Debug)]

652

    pub enum Seconds {}

653

654

    impl TimeResolution for Seconds {

655

        type Representation = i64;

656

657

        const FORMAT_SUFFIX: &'static str = "s";

658

659

7

        fn repr_to_duration(value: Self::Representation) -> Result<SignedDuration, TimeError> {

660

7

            if let Ok(unsigned) = u64::try_from(value) {

661

4

                Ok(SignedDuration::Positive(Duration::from_secs(unsigned)))

662

            } else {

663

3

                let positive = value

664

3

                    .checked_abs()

665

3

                    .and_then(|value| u64::try_from(value).ok())

666

3

                    .unwrap_or(u64::MAX);

667

3

                Ok(SignedDuration::Negative(Duration::from_secs(positive)))

668

669

7

670

671

14

        fn duration_to_repr(duration: SignedDuration) -> Result<Self::Representation, TimeError> {

672

14

            match duration {

673

7

                SignedDuration::Positive(duration) => {

674

7

                    i64::try_from(duration.as_secs()).map_err(|_| TimeError::DeltaNotRepresentable)

675

676

7

                SignedDuration::Negative(duration) => {

677

7

                    let rounded_up = duration

678

7

                        .checked_add(Duration::from_nanos(999_999_999))

679

7

                        .ok_or(TimeError::DeltaNotRepresentable)?;

680

7

                    i64::try_from(rounded_up.as_secs())

681

7

                        .map(|repr| -repr)

682

7

                        .map_err(|_| TimeError::DeltaNotRepresentable)

683

684

685

14

686

687

688

    /// A [`TimeResolution`] implementation that truncates time measurements to

689

    /// minutes. Internally, the number of minutes is represented as an `i32`,

690

    /// allowing a range of +/- ~4,086 years.

691

    #[derive(Debug)]

692

    pub enum Minutes {}

693

694

    impl TimeResolution for Minutes {

695

        type Representation = i32;

696

697

        const FORMAT_SUFFIX: &'static str = "m";

698

699

7

        fn repr_to_duration(value: Self::Representation) -> Result<SignedDuration, TimeError> {

700

7

            if let Ok(unsigned) = u64::try_from(value) {

701

4

                Ok(SignedDuration::Positive(Duration::from_secs(unsigned * 60)))

702

            } else {

703

3

                let positive = u64::try_from(i64::from(value).abs()).unwrap();

704

3

                Ok(SignedDuration::Negative(Duration::from_secs(positive * 60)))

705

706

7

707

708

14

        fn duration_to_repr(duration: SignedDuration) -> Result<Self::Representation, TimeError> {

709

14

            match duration {

710

7

                SignedDuration::Positive(duration) => i32::try_from(duration.as_secs() / 60)

711

7

                    .map_err(|_| TimeError::DeltaNotRepresentable),

712

7

                SignedDuration::Negative(duration) => i32::try_from((duration.as_secs() + 59) / 60)

713

7

                    .map(|repr| -repr)

714

7

                    .map_err(|_| TimeError::DeltaNotRepresentable),

715

716

14

717

718

719

    /// A [`TimeResolution`] implementation that truncates time measurements to

720

    /// hours. Internally, the number of hours is represented as an `i32`,

721

    /// allowing a range of +/- ~245,147 years.

722

    #[derive(Debug)]

723

    pub enum Hours {}

724

725

    impl TimeResolution for Hours {

726

        type Representation = i32;

727

728

        const FORMAT_SUFFIX: &'static str = "h";

729

730

6

        fn repr_to_duration(value: Self::Representation) -> Result<SignedDuration, TimeError> {

731

6

            if let Ok(unsigned) = u64::try_from(value) {

732

4

                Ok(SignedDuration::Positive(Duration::from_secs(

733

4

                    unsigned * 60 * 60,

734

4

)))

735

            } else {

736

2

                let positive = u64::try_from(i64::from(value).abs()).unwrap();

737

2

                Ok(SignedDuration::Negative(Duration::from_secs(

738

2

                    positive * 60 * 60,

739

2

)))

740

741

6

742

743

12

        fn duration_to_repr(duration: SignedDuration) -> Result<Self::Representation, TimeError> {

744

12

            const FACTOR: u64 = 60 * 60;

745

12

            match duration {

746

7

                SignedDuration::Positive(duration) => i32::try_from(duration.as_secs() / FACTOR)

747

7

                    .map_err(|_| TimeError::DeltaNotRepresentable),

748

5

                SignedDuration::Negative(duration) => {

749

5

                    i32::try_from((duration.as_secs() + FACTOR - 1) / FACTOR)

750

5

                        .map(|repr| -repr)

751

5

                        .map_err(|_| TimeError::DeltaNotRepresentable)

752

753

754

12

755

756

757

    /// A [`TimeResolution`] implementation that truncates time measurements to

758

    /// days. Internally, the number of days is represented as an `i32`,

759

    /// allowing a range of +/- ~5.88 million years.

760

    #[derive(Debug)]

761

    pub enum Days {}

762

763

    impl TimeResolution for Days {

764

        type Representation = i32;

765

766

        const FORMAT_SUFFIX: &'static str = "d";

767

768

7

        fn repr_to_duration(value: Self::Representation) -> Result<SignedDuration, TimeError> {

769

7

            if let Ok(unsigned) = u64::try_from(value) {

770

4

                Ok(SignedDuration::Positive(Duration::from_secs(

771

4

                    unsigned * 24 * 60 * 60,

772

4

)))

773

            } else {

774

3

                let positive = u64::try_from(i64::from(value).abs()).unwrap();

775

3

                Ok(SignedDuration::Negative(Duration::from_secs(

776

3

                    positive * 24 * 60 * 60,

777

3

)))

778

779

7

780

781

14

        fn duration_to_repr(duration: SignedDuration) -> Result<Self::Representation, TimeError> {

782

14

            const FACTOR: u64 = 24 * 60 * 60;

783

14

            match duration {

784

7

                SignedDuration::Positive(duration) => i32::try_from(duration.as_secs() / FACTOR)

785

7

                    .map_err(|_| TimeError::DeltaNotRepresentable),

786

7

                SignedDuration::Negative(duration) => {

787

7

                    Ok(i32::try_from((duration.as_secs() + FACTOR - 1) / FACTOR)

788

7

                        .map_or(i32::MIN, |repr| -repr))

789

790

791

14

792

793

794

    /// A [`TimeResolution`] implementation that truncates time measurements to

795

    /// weeks. Internally, the number of weeks is represented as an `i32`,

796

    /// allowing a range of +/- ~41.18 million years.

797

    #[derive(Debug)]

798

    pub enum Weeks {}

799

800

    impl TimeResolution for Weeks {

801

        type Representation = i32;

802

803

        const FORMAT_SUFFIX: &'static str = "w";

804

805

7

        fn repr_to_duration(value: Self::Representation) -> Result<SignedDuration, TimeError> {

806

7

            if let Ok(unsigned) = u64::try_from(value) {

807

4

                Ok(SignedDuration::Positive(Duration::from_secs(

808

4

                    unsigned * 7 * 24 * 60 * 60,

809

4

)))

810

            } else {

811

3

                let positive = u64::try_from(i64::from(value).abs()).unwrap();

812

3

                Ok(SignedDuration::Negative(Duration::from_secs(

813

3

                    positive * 7 * 24 * 60 * 60,

814

3

)))

815

816

7

817

818

14

        fn duration_to_repr(duration: SignedDuration) -> Result<Self::Representation, TimeError> {

819

14

            const FACTOR: u64 = 7 * 24 * 60 * 60;

820

14

            match duration {

821

7

                SignedDuration::Positive(duration) => i32::try_from(duration.as_secs() / FACTOR)

822

7

                    .map_err(|_| TimeError::DeltaNotRepresentable),

823

7

                SignedDuration::Negative(duration) => {

824

7

                    i32::try_from((duration.as_secs() + FACTOR - 1) / FACTOR)

825

7

                        .map(|repr| -repr)

826

7

                        .map_err(|_| TimeError::DeltaNotRepresentable)

827

828

829

14

830

831

832

1

    #[test]

833

1

    fn limited_resolution_duration_tests() {

834

14

        fn test_limited<Resolution: TimeResolution>(

835

14

            duration: Duration,

836

14

            expected_step: Resolution::Representation,

837

14

) {

838

14

            let limited = LimitedResolutionDuration::<Resolution>::try_from(duration).unwrap();

839

14

            assert_eq!(limited.representation, expected_step);

840

14

            let encoded = limited.as_ord_bytes().unwrap();

841

14

            println!("Encoded {limited:?} to {} bytes", encoded.len());

842

14

            let decoded =

843

14

                LimitedResolutionDuration::from_ord_bytes(ByteSource::Borrowed(&encoded)).unwrap();

844

14

            assert_eq!(limited, decoded);

845

14

846

1

847

7

        fn test_eq_limited<Resolution: TimeResolution>(

848

7

            duration: Duration,

849

7

            expected_step: Resolution::Representation,

850

7

) {

851

7

            test_limited::<Resolution>(duration, expected_step);

852

7

            let limited = LimitedResolutionDuration::<Resolution>::try_from(duration).unwrap();

853

7

            assert_eq!(duration, Duration::try_from(limited).unwrap());

854

7

855

1

856

1

        let truncating_seconds = 7 * 24 * 60 * 60 + 24 * 60 * 60 + 60 * 60 + 60 + 1;

857

1

        let truncating = Duration::new(u64::try_from(truncating_seconds).unwrap(), 987_654_321);

858

1

        test_limited::<Weeks>(truncating, 1);

859

1

        test_limited::<Days>(truncating, 8);

860

1

        test_limited::<Hours>(truncating, 8 * 24 + 1);

861

1

        test_limited::<Minutes>(truncating, 8 * 24 * 60 + 60 + 1);

862

1

        test_limited::<Seconds>(truncating, 8 * 24 * 60 * 60 + 60 * 60 + 60 + 1);

863

1

        test_limited::<Milliseconds>(truncating, truncating_seconds * 1_000 + 987);

864

1

        test_limited::<Microseconds>(truncating, truncating_seconds * 1_000_000 + 987_654);

865

1

866

1

        let forty_two_days = Duration::from_secs(42 * 24 * 60 * 60);

867

1

        test_eq_limited::<Weeks>(forty_two_days, 6);

868

1

        test_eq_limited::<Days>(forty_two_days, 42);

869

1

        test_eq_limited::<Hours>(forty_two_days, 42 * 24);

870

1

        test_eq_limited::<Minutes>(forty_two_days, 42 * 24 * 60);

871

1

        test_eq_limited::<Seconds>(forty_two_days, 42 * 24 * 60 * 60);

872

1

        test_eq_limited::<Milliseconds>(forty_two_days, 42 * 24 * 60 * 60 * 1_000);

873

1

        test_eq_limited::<Microseconds>(forty_two_days, 42 * 24 * 60 * 60 * 1_000_000);

874

1

875

876

    /// A timestamp (moment in time) stored with a limited `Resolution`. This

877

    /// type may be preferred to [`std::time::SystemTime`] because `SystemTime`

878

    /// serializes with nanosecond resolution. Often this level of precision is

879

    /// not needed and less storage and memory can be used.

880

///

881

    /// This type stores the representation of the timestamp as a

882

    /// [`LimitedResolutionDuration`] relative to `Epoch`.

883

///

884

    /// The `Resolution` type controls the storage size. The resolutions

885

    /// provided by BonsaiDb:

886

///

887

    /// - [`Weeks`]

888

    /// - [`Days`]

889

    /// - [`Hours`]

890

    /// - [`Minutes`]

891

    /// - [`Seconds`]

892

    /// - [`Milliseconds`]

893

    /// - [`Microseconds`]

894

    /// - [`Nanoseconds`]

895

///

896

    /// Other resolutions can be used by implementing [`TimeResolution`].

897

    /// BonsaiDb provides two [`TimeEpoch`] implementations:

898

///

899

    /// - [`UnixEpoch`]

900

    /// - [`BonsaiEpoch`]

901

192

    #[derive_where(Hash, Eq, PartialEq, Ord, PartialOrd, Clone, Copy)]

902

    pub struct LimitedResolutionTimestamp<Resolution: TimeResolution, Epoch: TimeEpoch>(

903

        LimitedResolutionDuration<Resolution>,

904

        PhantomData<Epoch>,

905

);

906

907

    impl<Resolution, Epoch> Default for LimitedResolutionTimestamp<Resolution, Epoch>

908

    where

909

        Resolution: TimeResolution,

910

        Epoch: TimeEpoch,

911

912

        fn default() -> Self {

913

            Self(LimitedResolutionDuration::default(), PhantomData)

914

915

916

917

    impl<Resolution, Epoch> Serialize for LimitedResolutionTimestamp<Resolution, Epoch>

918

    where

919

        Resolution: TimeResolution,

920

        Epoch: TimeEpoch,

921

922

764

        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>

923

764

        where

924

764

            S: serde::Serializer,

925

764

926

764

            self.0.serialize(serializer)

927

764

928

929

930

    impl<'de, Resolution, Epoch> Deserialize<'de> for LimitedResolutionTimestamp<Resolution, Epoch>

931

    where

932

        Resolution: TimeResolution,

933

        Epoch: TimeEpoch,

934

935

18564

        fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

936

18564

        where

937

18564

            D: serde::Deserializer<'de>,

938

18564

939

18564

            LimitedResolutionDuration::deserialize(deserializer)

940

18564

                .map(|duration| Self(duration, PhantomData))

941

18564

942

943

944

    /// An epoch for [`LimitedResolutionTimestamp`].

945

    pub trait TimeEpoch: Sized + Send + Sync {

946

        /// The name of this epoch, used in [`KeyEncoding::describe`] to

947

        /// disambiguate timestamps with different epochs.

948

        fn name() -> &'static str;

949

950

        /// The offset from [`UNIX_EPOCH`] for this epoch.

951

        fn epoch_offset() -> Duration;

952

953

954

    impl<Resolution, Epoch> LimitedResolutionTimestamp<Resolution, Epoch>

955

    where

956

        Resolution: TimeResolution,

957

        Epoch: TimeEpoch,

958

959

        /// Returns [`SystemTime::now()`] limited to `Resolution`. The timestamp

960

        /// will be truncated, not rounded.

961

///

962

        /// # Panics

963

///

964

        /// This function will panic [`SystemTime::now()`] is unable to be

965

        /// represented by `Resolution` and `Epoch`.

966

        #[must_use]

967

4511

        pub fn now() -> Self {

968

4511

            Self::try_from(SystemTime::now()).expect("now should always be representable")

969

4511

970

971

        /// Returns the duration since another timestamp. This returns None if

972

        /// `other` is before `self`,

973

        pub fn duration_since(

974

            &self,

975

            other: &impl AnyTimestamp,

976

        ) -> Result<Option<Duration>, TimeError> {

977

            let self_delta = self.duration_since_unix_epoch()?;

978

            let other_delta = other.duration_since_unix_epoch()?;

979

            Ok(self_delta.checked_sub(other_delta))

980

981

982

        /// Returns the absolute duration between `self` and `other`.

983

296

        pub fn duration_between(&self, other: &impl AnyTimestamp) -> Result<Duration, TimeError> {

984

296

            let self_delta = self.duration_since_unix_epoch()?;

985

296

            let other_delta = other.duration_since_unix_epoch()?;

986

296

            if self_delta < other_delta {

987

296

                Ok(other_delta - self_delta)

988

            } else {

989

                Ok(self_delta - other_delta)

990

991

296

992

993

        /// Returns the internal representation of this timestamp, which is a

994

        /// unit of `Resolution`.

995

6240

        pub const fn representation(&self) -> Resolution::Representation {

996

6240

            self.0.representation()

997

6240

998

999

        /// Returns a new timestamp using the `representation` provided.

1000

119

        pub fn from_representation(representation: Resolution::Representation) -> Self {

1001

119

            Self::from(LimitedResolutionDuration::new(representation))

1002

119

1003

1004

        /// Converts this value to a a decimal string containing the number of

1005

        /// seconds since the unix epoch (January 1, 1970 00:00:00 UTC).

1006

///

1007

        /// The resulting string can be parsed as well.

1008

///

1009

        /// ```rust

1010

        /// use bonsaidb_core::key::time::limited::{

1011

        ///     BonsaiEpoch, LimitedResolutionTimestamp, Milliseconds,

1012

        /// };

1013

///

1014

        /// let now = LimitedResolutionTimestamp::<Milliseconds, BonsaiEpoch>::now();

1015

        /// let timestamp = now.to_timestamp_string().unwrap();

1016

        /// let parsed = timestamp.parse().unwrap();

1017

        /// assert_eq!(now, parsed);

1018

        /// ```

1019

///

1020

        /// The difference between this function and `to_string()`] is that

1021

        /// `to_string()` will revert to using the underlying

1022

        /// [`LimitedResolutionDuration`]'s `to_string()` if a value is unable

1023

        /// to be converted to a value relative to the unix epoch.

1024

        pub fn to_timestamp_string(&self) -> Result<String, TimeError> {

1025

            let mut string = String::new();

1026

            self.display(&mut string).map(|()| string)

1027

1028

1029

2815

        fn display(&self, f: &mut impl Write) -> Result<(), TimeError> {

1030

2815

            let since_epoch = self.duration_since_unix_epoch()?;

1031

2815

            write!(f, "{}", since_epoch.as_secs()).map_err(|_| TimeError::InvalidValue)?;

1032

2815

            if since_epoch.subsec_nanos() > 0 {

1033

2803

                if since_epoch.subsec_nanos() % 1_000_000 == 0 {

1034

                    // Rendering any precision beyond milliseconds will yield 0s

1035

1

                    write!(f, ".{:03}", since_epoch.subsec_millis())

1036

1

                        .map_err(|_| TimeError::InvalidValue)

1037

2802

                } else if since_epoch.subsec_nanos() % 1_000 == 0 {

1038

1

                    write!(f, ".{:06}", since_epoch.subsec_micros())

1039

1

                        .map_err(|_| TimeError::InvalidValue)

1040

                } else {

1041

2801

                    write!(f, ".{:09}", since_epoch.subsec_nanos())

1042

2801

                        .map_err(|_| TimeError::InvalidValue)

1043

1044

            } else {

1045

                // No subsecond

1046

12

                Ok(())

1047

1048

2815

1049

1050

1051

    /// A timestamp that can report it sduration since the Unix Epoch.

1052

    pub trait AnyTimestamp {

1053

        /// Returns the [`Duration`] since January 1, 1970 00:00:00 UTC for this

1054

        /// timestamp.

1055

        fn duration_since_unix_epoch(&self) -> Result<Duration, TimeError>;

1056

1057

1058

    impl AnyTimestamp for SystemTime {

1059

        fn duration_since_unix_epoch(&self) -> Result<Duration, TimeError> {

1060

            Ok(self.duration_since(UNIX_EPOCH).unwrap())

1061

1062

1063

1064

    impl<Resolution, Epoch> AnyTimestamp for LimitedResolutionTimestamp<Resolution, Epoch>

1065

    where

1066

        Resolution: TimeResolution,

1067

        Epoch: TimeEpoch,

1068

1069

4095

        fn duration_since_unix_epoch(&self) -> Result<Duration, TimeError> {

1070

4095

            let relative_offset = Resolution::repr_to_duration(self.0.representation)?;

1071

4095

            match relative_offset {

1072

8

                SignedDuration::Positive(offset) => Epoch::epoch_offset()

1073

8

                    .checked_add(offset)

1074

8

                    .ok_or(TimeError::DeltaNotRepresentable),

1075

4087

                SignedDuration::Negative(offset) => Epoch::epoch_offset()

1076

4087

                    .checked_sub(offset)

1077

4087

                    .ok_or(TimeError::DeltaNotRepresentable),

1078

1079

4095

1080

1081

1082

    impl<Resolution, Epoch> Debug for LimitedResolutionTimestamp<Resolution, Epoch>

1083

    where

1084

        Resolution: TimeResolution,

1085

        Epoch: TimeEpoch,

1086

1087

216

        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {

1088

216

            write!(f, "LimitedResolutionTimestamp({self})")

1089

216

1090

1091

1092

    impl<Resolution, Epoch> Display for LimitedResolutionTimestamp<Resolution, Epoch>

1093

    where

1094

        Resolution: TimeResolution,

1095

        Epoch: TimeEpoch,

1096

1097

2815

        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {

1098

2815

            self.display(f).or_else(|_| Display::fmt(&self.0, f))

1099

2815

1100

1101

1102

    impl<Resolution, Epoch> FromStr for LimitedResolutionTimestamp<Resolution, Epoch>

1103

    where

1104

        Resolution: TimeResolution,

1105

        Epoch: TimeEpoch,

1106

1107

        type Err = TimeError;

1108

1109

7

        fn from_str(s: &str) -> Result<Self, Self::Err> {

1110

7

            let mut parts = s.split('.');

1111

7

            let seconds = parts.next().ok_or(TimeError::InvalidValue)?;

1112

7

            let seconds = seconds

1113

7

                .parse::<u64>()

1114

7

                .map_err(|_| TimeError::InvalidValue)?;

1115

1116

7

            let duration = if let Some(subseconds_str) = parts.next() {

1117

3

                if subseconds_str.len() > 9 || parts.next().is_some() {

1118

                    return Err(TimeError::InvalidValue);

1119

3

1120

3

                let subseconds = subseconds_str

1121

3

                    .parse::<u32>()

1122

3

                    .map_err(|_| TimeError::InvalidValue)?;

1123

1124

3

                let nanos =

1125

3

                    subseconds * 10_u32.pow(u32::try_from(9 - subseconds_str.len()).unwrap());

1126

3

                Duration::new(seconds, nanos)

1127

            } else {

1128

4

                Duration::from_secs(seconds)

1129

};

1130

1131

7

            let epoch = Epoch::epoch_offset();

1132

7

            let duration = if duration < epoch {

1133

7

                SignedDuration::Negative(epoch - duration)

1134

            } else {

1135

                SignedDuration::Positive(duration - epoch)

1136

};

1137

            Ok(Self::from(

1138

7

                LimitedResolutionDuration::<Resolution>::try_from(duration)?,

1139

))

1140

7

1141

1142

1143

1

    #[test]

1144

1

    fn timestamp_parse_tests() {

1145

7

        fn test_roundtrip_parsing<Resolution: TimeResolution>() {

1146

7

            let original = LimitedResolutionTimestamp::<Resolution, BonsaiEpoch>::now();

1147

7

            let unix_timestamp = original.to_string();

1148

7

            let parsed = unix_timestamp.parse().unwrap();

1149

7

            assert_eq!(

1150

1

                original, parsed,

1151

1

                "{original} produced {unix_timestamp}, but parsed {parsed}"

1152

1

);

1153

7

1154

1

1155

1

        test_roundtrip_parsing::<Weeks>();

1156

1

        test_roundtrip_parsing::<Days>();

1157

1

        test_roundtrip_parsing::<Minutes>();

1158

1

        test_roundtrip_parsing::<Seconds>();

1159

1

        test_roundtrip_parsing::<Milliseconds>();

1160

1

        test_roundtrip_parsing::<Microseconds>();

1161

1

        test_roundtrip_parsing::<Nanoseconds>();

1162

1

1163

1164

    impl<'k, Resolution, Epoch> Key<'k> for LimitedResolutionTimestamp<Resolution, Epoch>

1165

    where

1166

        Resolution: TimeResolution,

1167

        Epoch: TimeEpoch,

1168

1169

        const CAN_OWN_BYTES: bool = false;

1170

1171

        fn from_ord_bytes<'e>(bytes: ByteSource<'k, 'e>) -> Result<Self, Self::Error> {

1172

            let duration = LimitedResolutionDuration::<Resolution>::from_ord_bytes(bytes)?;

1173

            Ok(Self::from(duration))

1174

1175

1176

1177

    impl<Resolution, Epoch> KeyEncoding<Self> for LimitedResolutionTimestamp<Resolution, Epoch>

1178

    where

1179

        Resolution: TimeResolution,

1180

        Epoch: TimeEpoch,

1181

1182

        type Error = TimeError;

1183

1184

        const LENGTH: Option<usize> = None;

1185

1186

1

        fn describe<Visitor>(visitor: &mut Visitor)

1187

1

        where

1188

1

            Visitor: KeyVisitor,

1189

1

1190

1

            visitor.visit_composite(

1191

1

                CompositeKind::Struct(Cow::Borrowed(

1192

1

                    "bonsaidb::core::key::time::LimitedResolutionTimestamp",

1193

1

)),

1194

1

1,

1195

1

);

1196

1

            visitor.visit_composite_attribute("epoch", Epoch::epoch_offset().as_nanos());

1197

1

            <Resolution::Representation as KeyEncoding>::describe(visitor);

1198

1

1199

1200

        fn as_ord_bytes(&self) -> Result<Cow<'_, [u8]>, Self::Error> {

1201

            self.0.as_ord_bytes()

1202

1203

1204

1205

    impl<Resolution, Epoch> From<LimitedResolutionDuration<Resolution>>

1206

        for LimitedResolutionTimestamp<Resolution, Epoch>

1207

    where

1208

        Resolution: TimeResolution,

1209

        Epoch: TimeEpoch,

1210

1211

9326

        fn from(duration: LimitedResolutionDuration<Resolution>) -> Self {

1212

9326

            Self(duration, PhantomData)

1213

9326

1214

1215

1216

    impl<Resolution, Epoch> From<LimitedResolutionTimestamp<Resolution, Epoch>>

1217

        for LimitedResolutionDuration<Resolution>

1218

    where

1219

        Resolution: TimeResolution,

1220

        Epoch: TimeEpoch,

1221

1222

        fn from(time: LimitedResolutionTimestamp<Resolution, Epoch>) -> Self {

1223

            time.0

1224

1225

1226

1227

    impl<Resolution, Epoch> TryFrom<SystemTime> for LimitedResolutionTimestamp<Resolution, Epoch>

1228

    where

1229

        Resolution: TimeResolution,

1230

        Epoch: TimeEpoch,

1231

1232

        type Error = TimeError;

1233

1234

4559

        fn try_from(time: SystemTime) -> Result<Self, TimeError> {

1235

4559

            let epoch = UNIX_EPOCH

1236

4559

                .checked_add(Epoch::epoch_offset())

1237

4559

                .ok_or(TimeError::DeltaNotRepresentable)?;

1238

4559

            match time.duration_since(epoch) {

1239

34

                Ok(duration) => {

1240

34

                    LimitedResolutionDuration::try_from(SignedDuration::Positive(duration))

1241

34

                        .map(Self::from)

1242

1243

4525

                Err(_) => match epoch.duration_since(time) {

1244

4525

                    Ok(duration) => {

1245

4525

                        LimitedResolutionDuration::try_from(SignedDuration::Negative(duration))

1246

4525

                            .map(Self::from)

1247

1248

                    Err(_) => Err(TimeError::DeltaNotRepresentable),

1249

},

1250

1251

4559

1252

1253

1254

    impl<Resolution, Epoch> TryFrom<LimitedResolutionTimestamp<Resolution, Epoch>> for SystemTime

1255

    where

1256

        Resolution: TimeResolution,

1257

        Epoch: TimeEpoch,

1258

1259

        type Error = TimeError;

1260

1261

32

        fn try_from(

1262

32

            time: LimitedResolutionTimestamp<Resolution, Epoch>,

1263

32

        ) -> Result<Self, TimeError> {

1264

32

            let since_epoch = SignedDuration::try_from(time.0)?;

1265

32

            let epoch = UNIX_EPOCH

1266

32

                .checked_add(Epoch::epoch_offset())

1267

32

                .ok_or(TimeError::DeltaNotRepresentable)?;

1268

32

            let time = match since_epoch {

1269

17

                SignedDuration::Positive(since_epoch) => epoch.checked_add(since_epoch),

1270

15

                SignedDuration::Negative(since_epoch) => epoch.checked_sub(since_epoch),

1271

};

1272

1273

32

            time.ok_or(TimeError::DeltaNotRepresentable)

1274

32

1275

1276

1277

    /// A [`TimeEpoch`] implementation that allows storing

1278

    /// [`LimitedResolutionTimestamp`] relative to the "unix epoch": January 1,

1279

    /// 1970 00:00:00 UTC.

1280

    pub struct UnixEpoch;

1281

1282

    impl TimeEpoch for UnixEpoch {

1283

        fn name() -> &'static str {

1284

            "Unix"

1285

1286

1287

24

        fn epoch_offset() -> Duration {

1288

24

            Duration::ZERO

1289

24

1290

1291

1292

    /// A [`TimeEpoch`] implementation that allows storing

1293

    /// [`LimitedResolutionTimestamp`] relative to the 10-year anniversary of

1294

    /// BonsaiDb: March 20, 2031 04:31:47 UTC.

1295

///

1296

    /// ## Why use [`BonsaiEpoch`] instead of [`UnixEpoch`]?

1297

///

1298

    /// [`LimitedResolutionTimestamp`] uses [`ordered-varint::Variable`] to

1299

    /// implement [`Key`], which encodes the underlying value in as few bytes as

1300

    /// possible while still preserving the ordering required by [`Key`].

1301

///

1302

    /// Many applications are not storing timestamps that predate the

1303

    /// application being developed. When there is a likelihood that timestamps

1304

    /// are closer to "now" than they are to the unix timestamp (January 1, 1970

1305

    /// 00:00:00 UTC), the [`BonsaiEpoch`] will consistently encode the

1306

    /// underlying representation in fewer bytes than when using [`UnixEpoch`].

1307

///

1308

    /// We hope BonsaiDb is a viable database option for many years. By setting

1309

    /// this epoch 10 years from the start of BonsaiDb, it allows the internal

1310

    /// representation of timestamps to slowly decrease in size until the

1311

    /// 10-year anniversary. Over the following 10 years, the size will grow

1312

    /// back to the same size it was at its conception, and then slowly grow as

1313

    /// needed from that point on.

1314

    pub struct BonsaiEpoch;

1315

1316

    impl BonsaiEpoch {

1317

        const EPOCH: Duration = Duration::new(1_931_747_507, 0);

1318

1319

1320

    impl TimeEpoch for BonsaiEpoch {

1321

        fn name() -> &'static str {

1322

            "BonsaiDb"

1323

1324

1325

8671

        fn epoch_offset() -> Duration {

1326

8671

            Self::EPOCH

1327

8671

1328

1329

1330

1

    #[test]

1331

1

    fn limited_resolution_timestamp_tests() {

1332

8

        fn test_resolution<Resolution: TimeResolution>(resolution: Duration) {

1333

8

            let now_in_seconds = LimitedResolutionTimestamp::<Resolution, UnixEpoch>::now();

1334

8

            let as_system = SystemTime::try_from(now_in_seconds).unwrap();

1335

8

            let as_limited =

1336

8

                LimitedResolutionTimestamp::<Resolution, UnixEpoch>::try_from(as_system).unwrap();

1337

8

            assert_eq!(as_limited, now_in_seconds);

1338

1

1339

8

            let now_in_seconds = LimitedResolutionTimestamp::<Resolution, BonsaiEpoch>::now();

1340

8

            let as_system = SystemTime::try_from(now_in_seconds).unwrap();

1341

8

            let as_limited =

1342

8

                LimitedResolutionTimestamp::<Resolution, BonsaiEpoch>::try_from(as_system).unwrap();

1343

8

            assert_eq!(as_limited, now_in_seconds);

1344

1

1345

8

            let slightly_before_epoch = UNIX_EPOCH + BonsaiEpoch::EPOCH

1346

8

                - Duration::from_nanos(u64::try_from(resolution.as_nanos() / 2).unwrap());

1347

8

            let unix_epoch_in_recent =

1348

8

                LimitedResolutionTimestamp::<Resolution, BonsaiEpoch>::try_from(

1349

8

                    slightly_before_epoch,

1350

8

1351

8

                .unwrap();

1352

8

            let as_system = SystemTime::try_from(unix_epoch_in_recent).unwrap();

1353

8

            let as_limited =

1354

8

                LimitedResolutionTimestamp::<Resolution, BonsaiEpoch>::try_from(as_system).unwrap();

1355

8

            assert!(

1356

8

                slightly_before_epoch

1357

8

                    .duration_since(as_system)

1358

8

                    .expect("timestamp should have been trunctated towards MIN")

1359

8

                    < resolution

1360

8

);

1361

8

            assert_eq!(as_limited, unix_epoch_in_recent);

1362

1

1363

8

            let slightly_after_epoch = UNIX_EPOCH

1364

8

                + BonsaiEpoch::EPOCH

1365

8

                + Duration::from_nanos(u64::try_from(resolution.as_nanos() / 2).unwrap());

1366

8

            let unix_epoch_in_recent =

1367

8

                LimitedResolutionTimestamp::<Resolution, BonsaiEpoch>::try_from(

1368

8

                    slightly_after_epoch,

1369

8

1370

8

                .unwrap();

1371

8

            let as_system = SystemTime::try_from(unix_epoch_in_recent).unwrap();

1372

8

            println!("{slightly_after_epoch:?} converted to {unix_epoch_in_recent} and back as {as_system:?}");

1373

8

            let as_limited =

1374

8

                LimitedResolutionTimestamp::<Resolution, BonsaiEpoch>::try_from(as_system).unwrap();

1375

8

            assert!(

1376

8

                slightly_after_epoch

1377

8

                    .duration_since(as_system)

1378

8

                    .expect("timestamp should have been truncated towards 0")

1379

8

                    < resolution

1380

8

);

1381

8

            assert_eq!(as_limited, unix_epoch_in_recent);

1382

8

1383

1

1384

1

        test_resolution::<Weeks>(Duration::from_secs(7 * 24 * 60 * 60));

1385

1

        test_resolution::<Days>(Duration::from_secs(24 * 60 * 60));

1386

1

        test_resolution::<Hours>(Duration::from_secs(60 * 60));

1387

1

        test_resolution::<Minutes>(Duration::from_secs(60));

1388

1

        test_resolution::<Seconds>(Duration::from_secs(1));

1389

1

        test_resolution::<Milliseconds>(Duration::from_millis(1));

1390

1

        test_resolution::<Microseconds>(Duration::from_micros(1));

1391

1

        test_resolution::<Nanoseconds>(Duration::from_nanos(1));

1392

1

1393

1394

1

    #[test]

1395

1

    fn serialization_tests() {

1396

8

        fn test_serialization<Resolution: TimeResolution>() {

1397

8

            let original = LimitedResolutionTimestamp::<Resolution, BonsaiEpoch>::now();

1398

8

            let serialized = pot::to_vec(&original).unwrap();

1399

8

            let deserialized = pot::from_slice(&serialized).unwrap();

1400

8

            assert_eq!(original, deserialized);

1401

8

1402

1

1403

1

        test_serialization::<Weeks>();

1404

1

        test_serialization::<Days>();

1405

1

        test_serialization::<Hours>();

1406

1

        test_serialization::<Minutes>();

1407

1

        test_serialization::<Seconds>();

1408

1

        test_serialization::<Milliseconds>();

1409

1

        test_serialization::<Microseconds>();

1410

1

        test_serialization::<Nanoseconds>();

1411

1

1412

1413

1414

/// A signed duration of time represented in weeks (604,800 seconds).

1415

/// Internally, the number of weeks is represented as an `i32`,

1416

/// allowing a range of +/- ~41.18 million years.

1417

pub type Weeks = limited::LimitedResolutionDuration<limited::Weeks>;

1418

1419

/// A signed duration of time represented in days (86,400 seconds). Internally,

1420

/// the number of days is represented as an `i32`, allowing a range of +/- ~5.88

1421

/// million years.

1422

pub type Days = limited::LimitedResolutionDuration<limited::Days>;

1423

1424

/// A signed duration of time represented in hours (3,600 seconds). Internally,

1425

/// the number of hours is represented as an `i32`, allowing a range of +/-

1426

/// ~245,147 years.

1427

pub type Hours = limited::LimitedResolutionDuration<limited::Hours>;

1428

1429

/// A signed duration of time represented in minutes (60 seconds). Internally,

1430

/// the number of minutes is represented as an `i32`,

1431

/// allowing a range of +/- ~4,086 years.

1432

pub type Minutes = limited::LimitedResolutionDuration<limited::Minutes>;

1433

1434

/// A signed duration of time represented in seconds (with no partial

1435

/// subseconds). Internally, the number of seconds is represented as an `i64`,

1436

/// allowing a range of +/- ~21 times the age of the universe.

1437

pub type Seconds = limited::LimitedResolutionDuration<limited::Seconds>;

1438

1439

/// A signed duration of time represented in milliseconds (1/1,000th of a

1440

/// second). Internally, the number of milliseconds is represented as an `i64`,

1441

/// allowing a range of +/- ~292.5 million years.

1442

pub type Milliseconds = limited::LimitedResolutionDuration<limited::Milliseconds>;

1443

1444

/// A signed duration of time represented in microseconds (1/1,000,000th of a

1445

/// second). Internally, the number of microseconds is represented as an `i64`,

1446

/// allowing a range of +/- ~292,471 years.

1447

pub type Microseconds = limited::LimitedResolutionDuration<limited::Microseconds>;

1448

1449

/// A signed duration of time represented in nanoseconds (1/1,000,000,000th of a

1450

/// second). Internally, the number of microseconds is represented as an `i64`,

1451

/// allowing a range of +/- ~292.5 years.

1452

pub type Nanoseconds = limited::LimitedResolutionDuration<limited::Nanoseconds>;

1453

1454

/// A timestamp stored as the number of weeks (604,800 seconds) relative to

1455

/// [`UnixEpoch`]. Internally, the number of weeks is represented as an `i32`,

1456

/// allowing a range of +/- ~41.18 million years.

1457

pub type WeeksSinceUnixEpoch = limited::LimitedResolutionTimestamp<limited::Weeks, UnixEpoch>;

1458

1459

/// A timestamp stored as the number of days (86,400 seconds) relative to

1460

/// [`UnixEpoch`]. Internally, the number of days is represented as an `i32`,

1461

/// allowing a range of +/- ~5.88 million years.

1462

pub type DaysSinceUnixEpoch = limited::LimitedResolutionTimestamp<limited::Days, UnixEpoch>;

1463

1464

/// A timestamp stored as the number of hours (3,600 seconds) relative to

1465

/// [`UnixEpoch`]. Internally, the number of hours is represented as an `i32`,

1466

/// allowing a range of +/- ~245,147 years.

1467

pub type HoursSinceUnixEpoch = limited::LimitedResolutionTimestamp<limited::Hours, UnixEpoch>;

1468

1469

/// A timestamp stored as the number of minutes (60 seconds) relative to

1470

/// [`UnixEpoch`]. Internally, the number of minutes is represented as an `i32`,

1471

/// allowing a range of +/- ~4,086 years.

1472

pub type MinutesSinceUnixEpoch = limited::LimitedResolutionTimestamp<limited::Minutes, UnixEpoch>;

1473

1474

/// A timestamp stored as the number of seconds (with no partial subseconds)

1475

/// relative to [`UnixEpoch`]. Internally, the number of seconds is represented

1476

/// as an `i64`, allowing a range of +/- ~21 times the age of the universe.

1477

pub type SecondsSinceUnixEpoch = limited::LimitedResolutionTimestamp<limited::Seconds, UnixEpoch>;

1478

1479

/// A timestamp stored as the number of milliseconds (1/1,000th of a second)

1480

/// relative to [`UnixEpoch`]. Internally, the number of milliseconds is

1481

/// represented as an `i64`, allowing a range of +/- ~292.5 million years.

1482

pub type MillisecondsSinceUnixEpoch =

1483

    limited::LimitedResolutionTimestamp<limited::Milliseconds, UnixEpoch>;

1484

1485

/// A timestamp stored as the number of microseconds (1/1,000,000th of a second)

1486

/// relative to [`UnixEpoch`]. Internally, the number of microseconds is

1487

/// represented as an `i64`, allowing a range of +/- ~292,471 years.

1488

pub type MicrosecondsSinceUnixEpoch =

1489

    limited::LimitedResolutionTimestamp<limited::Microseconds, UnixEpoch>;

1490

1491

/// A timestamp stored as the number of nanoseconds (1/1,000,000,000th of a

1492

/// second) relative to [`UnixEpoch`]. Internally, the number of microseconds is

1493

/// represented as an `i64`, allowing a range of +/- ~292.5 years.

1494

pub type NanosecondsSinceUnixEpoch =

1495

    limited::LimitedResolutionTimestamp<limited::Nanoseconds, UnixEpoch>;

1496

1497

/// A timestamp stored as the number of weeks (604,800 seconds) relative to

1498

/// [`BonsaiEpoch`]. Internally, the number of weeks is represented as an `i32`,

1499

/// allowing a range of +/- ~41.18 million years.

1500

pub type TimestampAsWeeks = limited::LimitedResolutionTimestamp<limited::Weeks, BonsaiEpoch>;

1501

1502

/// A timestamp stored as the number of days (86,400 seconds) relative to

1503

/// [`BonsaiEpoch`]. Internally, the number of days is represented as an `i32`,

1504

/// allowing a range of +/- ~5.88 million years.

1505

pub type TimestampAsDays = limited::LimitedResolutionTimestamp<limited::Days, BonsaiEpoch>;

1506

1507

/// A timestamp stored as the number of hours (3,600 seconds) relative to

1508

/// [`BonsaiEpoch`]. Internally, the number of hours is represented as an `i32`,

1509

/// allowing a range of +/- ~245,147 years.

1510

pub type TimestampAsHours = limited::LimitedResolutionTimestamp<limited::Hours, BonsaiEpoch>;

1511

1512

/// A timestamp stored as the number of minutes (60 seconds) relative to

1513

/// [`BonsaiEpoch`]. Internally, the number of minutes is represented as an `i32`,

1514

/// allowing a range of +/- ~4,086 years.

1515

pub type TimestampAsMinutes = limited::LimitedResolutionTimestamp<limited::Minutes, BonsaiEpoch>;

1516

1517

/// A timestamp stored as the number of seconds (with no partial subseconds)

1518

/// relative to [`BonsaiEpoch`]. Internally, the number of seconds is represented

1519

/// as an `i64`, allowing a range of +/- ~21 times the age of the universe.

1520

pub type TimestampAsSeconds = limited::LimitedResolutionTimestamp<limited::Seconds, BonsaiEpoch>;

1521

1522

/// A timestamp stored as the number of milliseconds (1/1,000th of a second)

1523

/// relative to [`BonsaiEpoch`]. Internally, the number of milliseconds is

1524

/// represented as an `i64`, allowing a range of +/- ~292.5 million years.

1525

pub type TimestampAsMilliseconds =

1526

    limited::LimitedResolutionTimestamp<limited::Milliseconds, BonsaiEpoch>;

1527

1528

/// A timestamp stored as the number of microseconds (1/1,000,000th of a second)

1529

/// relative to [`BonsaiEpoch`]. Internally, the number of microseconds is

1530

/// represented as an `i64`, allowing a range of +/- ~292,471 years.

1531

pub type TimestampAsMicroseconds =

1532

    limited::LimitedResolutionTimestamp<limited::Microseconds, BonsaiEpoch>;

1533

1534

/// A timestamp stored as the number of nanoseconds (1/1,000,000,000th of a

1535

/// second) relative to [`BonsaiEpoch`]. Internally, the number of microseconds is

1536

/// represented as an `i64`, allowing a range of +/- ~292.5 years.

1537

pub type TimestampAsNanoseconds =

1538

    limited::LimitedResolutionTimestamp<limited::Nanoseconds, BonsaiEpoch>;