Struct bonsaidb_core::key::time::limited::LimitedResolutionTimestamp

pub struct LimitedResolutionTimestamp<Resolution: TimeResolution, Epoch: TimeEpoch>(/* private fields */);

A timestamp (moment in time) stored with a limited Resolution. This type may be preferred to std::time::SystemTime because SystemTime serializes with nanosecond resolution. Often this level of precision is not needed and less storage and memory can be used.

This type stores the representation of the timestamp as a LimitedResolutionDuration relative to Epoch.

The Resolution type controls the storage size. The resolutions provided by BonsaiDb:

• Weeks
• Days
• Hours
• Minutes
• Seconds
• Milliseconds
• Microseconds
• Nanoseconds

Other resolutions can be used by implementing TimeResolution. BonsaiDb provides two TimeEpoch implementations:

• UnixEpoch
• BonsaiEpoch

Implementations

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

pub fn now() -> Self

Returns SystemTime::now() limited to Resolution. The timestamp will be truncated, not rounded.

Panics

This function will panic SystemTime::now() is unable to be represented by Resolution and Epoch.

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

Returns the duration since another timestamp. This returns None if other is before self,

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

Returns the absolute duration between self and other.

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

Returns the internal representation of this timestamp, which is a unit of Resolution.

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

Returns a new timestamp using the representation provided.

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

Converts this value to a a decimal string containing the number of seconds since the unix epoch (January 1, 1970 00:00:00 UTC).

The resulting string can be parsed as well.

use bonsaidb_core::key::time::limited::{
    BonsaiEpoch, LimitedResolutionTimestamp, Milliseconds,
};

let now = LimitedResolutionTimestamp::<Milliseconds, BonsaiEpoch>::now();
let timestamp = now.to_timestamp_string().unwrap();
let parsed = timestamp.parse().unwrap();
assert_eq!(now, parsed);

The difference between this function and to_string()] is that to_string() will revert to using the underlying LimitedResolutionDuration’s to_string() if a value is unable to be converted to a value relative to the unix epoch.

Trait Implementations

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

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

Returns the Duration since January 1, 1970 00:00:00 UTC for this timestamp.

impl<Resolution: TimeResolution, Epoch: TimeEpoch> Clone for LimitedResolutionTimestamp<Resolution, Epoch>

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

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

Formats the value using the given formatter.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

fn default() -> Self

Returns the “default value” for a type.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

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

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

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

Formats the value using the given formatter.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

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

Converts to this type from the input type.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

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

Converts to this type from the input type.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

type Err = TimeError

The associated error which can be returned from parsing.

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

Parses a string s to return a value of this type.

impl<Resolution: TimeResolution, Epoch: TimeEpoch> Hash for LimitedResolutionTimestamp<Resolution, Epoch>

fn hash<__H: Hasher>(&self, __state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

const CAN_OWN_BYTES: bool = false

If true, this type can benefit from an owned Vec<u8>. This flag is used as a hint of whether to attempt to do memcpy operations in some decoding operations to avoid extra allocations.

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

Deserialize a sequence of bytes previously encoded with KeyEncoding::as_ord_bytes.

fn first_value() -> Result<Self, NextValueError>

Return the first value in sequence for this type. Not all types implement this.

fn next_value(&self) -> Result<Self, NextValueError>

Return the next value in sequence for this type. Not all types implement this. Instead of wrapping/overflowing, None should be returned.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

type Error = TimeError

The error type that can be produced by either serialization or deserialization.

const LENGTH: Option<usize> = None

The size of the key, if constant. If this type doesn’t produce the same number of bytes for each value, this should be None.

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

where Visitor: KeyVisitor,

Describes this type by invoking functions on visitor describing the key being encoded.

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

Convert self into a Cow<'_, [u8]> containing bytes that are able to be compared via memcmp in a way that is comptaible with its own Ord implementation.

impl<Resolution: TimeResolution, Epoch: TimeEpoch> Ord for LimitedResolutionTimestamp<Resolution, Epoch>

fn cmp(&self, __other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl<Resolution: TimeResolution, Epoch: TimeEpoch> PartialEq for LimitedResolutionTimestamp<Resolution, Epoch>

fn eq(&self, __other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<Resolution: TimeResolution, Epoch: TimeEpoch> PartialOrd for LimitedResolutionTimestamp<Resolution, Epoch>

fn partial_cmp(&self, __other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

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

where S: Serializer,

Serialize this value into the given Serde serializer.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

type Error = TimeError

The type returned in the event of a conversion error.

fn try_from( time: LimitedResolutionTimestamp<Resolution, Epoch> ) -> Result<Self, TimeError>

Performs the conversion.

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

where Resolution: TimeResolution, Epoch: TimeEpoch,

type Error = TimeError

The type returned in the event of a conversion error.

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

Performs the conversion.

impl<Resolution: TimeResolution, Epoch: TimeEpoch> Copy for LimitedResolutionTimestamp<Resolution, Epoch>

impl<Resolution: TimeResolution, Epoch: TimeEpoch> Eq for LimitedResolutionTimestamp<Resolution, Epoch>