Struct SeqV

pub struct SeqV<M, T = Vec<u8>> {
    pub seq: u64,
    pub meta: Option<M>,
    pub data: T,
}

Some value bound with a seq number.

SeqV is the meta-service API level generic value. Meta-service application uses this type to interact with meta-service.

Inside the meta-service, the value is stored in the form of Marked, which could be a tombstone. A Marked::TombStone is converted to None::<SeqV> and a Marked::Normal is converted to Some::<SeqV>.

A Marked::TombStone also has an internal_seq, representing the freshness of the tombstone. internal_seq will be discarded when Marked::TombStone is converted to None::<SeqV>.

Fields

seq: u64

meta: Option<M>

data: T

Implementations

impl<M, T> SeqV<M, T>

pub fn new(seq: u64, data: T) -> Self

pub fn new_with_meta(seq: u64, meta: Option<M>, data: T) -> Self

pub fn with_seq(self, seq: u64) -> Self

pub fn with_meta(self, m: Option<M>) -> Self

pub fn with_value(self, v: T) -> Self

pub fn map<U>(self, f: impl FnOnce(T) -> U) -> SeqV<M, U>

Convert data to type U and leave seq and meta unchanged.

pub fn try_map<U, E>( self, f: impl FnOnce(T) -> Result<U, E>, ) -> Result<SeqV<M, U>, E>

Try to convert data to type U and leave seq and meta unchanged. f returns an error if the conversion fails.

Trait Implementations

impl<M: Clone, T: Clone> Clone for SeqV<M, T>

fn clone(&self) -> SeqV<M, T>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<M, T> Debug for SeqV<M, T>

where M: Debug, T: Debug,

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

Formats the value using the given formatter.

impl<M: Default, T: Default> Default for SeqV<M, T>

fn default() -> SeqV<M, T>

Returns the “default value” for a type.

impl<M, T> Deref for SeqV<M, T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<M, T> DerefMut for SeqV<M, T>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<M, T> From<SeqV<M, T>> for SeqMarked<(Option<M>, T)>

fn from(value: SeqV<M, T>) -> Self

Converts to this type from the input type.

impl<M: PartialEq, T: PartialEq> PartialEq for SeqV<M, T>

fn eq(&self, other: &SeqV<M, T>) -> bool

Tests for self and other values to be equal, and is used by ==.

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

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

impl<M, V> SeqValue<M, V> for SeqV<M, V>

fn seq(&self) -> u64

Return the sequence number of the value.

fn value(&self) -> Option<&V>

Return the reference of the value.

fn into_value(self) -> Option<V>

Consume the value and return the value.

fn meta(&self) -> Option<&M>

Return the reference of metadata of the value.

fn unpack(self) -> (u64, Option<V>)

where Self: Sized,

Consume self and return the sequence number and the value.

fn expires_at_ms_opt(&self) -> Option<u64>

where M: Expirable,

Return the absolute expire time in millisecond since 1970-01-01 00:00:00.

fn expires_at_ms(&self) -> u64

where M: Expirable,

Returns the absolute expiration time in milliseconds since the Unix epoch (1970-01-01 00:00:00 UTC).

fn is_expired(&self, now_ms: u64) -> bool

where M: Expirable,

Return true if the record is expired at the given time in milliseconds since the Unix epoch (1970-01-01 00:00:00 UTC).

impl<M: Eq, T: Eq> Eq for SeqV<M, T>

impl<M, T> StructuralPartialEq for SeqV<M, T>