Struct Entry 

pub struct Entry<const MCL: usize, const MCC: usize, const MPL: usize, N, S, PD> { /* private fields */ }

The metadata associated with each Willow Payload string.

Entries are the central concept in Willow. In order to make any bytestring of data accessible to Willow, you need to create an Entry describing its metadata. Specifically, an Entry consists of

• a namespace_id (roughly, this addresses a universe of Willow data, fully independent from all data (i.e., Entries) of different namespace ids) of type N,
• a subspace_id (roughly, a fully indendent part of a namespace, typically subspaces correspond to individual users) of type S,
• a path (roughly, a file-system-like way of arranging payloads hierarchically within a subspace) of type Path,
• a timestamp (newer Entries can overwrite certain older Entries),
• a payload_length (the length of the payload string), and
• a payload_digest (a secure hash of the payload string being inserted into Willow).

To access these six fields, use the methods of the Entrylike trait (which Entry implements). The EntrylikeExt trait provides additional helper methods, for example, methods to check which Entries can delete which other Entries.

To create Entries, use the Entry::builder or Entry::prefilled_builder functions.

Example

use willow_data_model::prelude::*;

let entry = Entry::builder()
    .namespace_id("family")
    .subspace_id("alfie")
    .path(Path::<4, 4, 4>::new())
    .timestamp(12345)
    .payload_digest("some_hash")
    .payload_length(17)
    .build().unwrap();

assert_eq!(*entry.wdm_subspace_id(), "alfie");

let newer = Entry::prefilled_builder(&entry).timestamp(99999).build().unwrap();
assert!(newer.wdm_prunes(&entry));

Spec definition.

Implementations

impl<const MCL: usize, const MCC: usize, const MPL: usize, N, S, PD> Entry<MCL, MCC, MPL, N, S, PD>

pub fn builder() -> EntryBuilder<MCL, MCC, MPL, N, S, PD>

Creates a builder for Entry.

Examples

use willow_data_model::prelude::*;

// Supplying incomplete data errors.
assert!(
    Entry::builder()
    .path(Path::<4, 4, 4>::new())
    .namespace_id("family")
    .subspace_id("alfie")
    .payload_digest("some_hash")
    // timestamp and payload_length are missing!
    .build().is_err()
);

// Supplying all necessary data yields an entry.
let entry = Entry::builder()
    .namespace_id("family")
    .subspace_id("alfie")
    .path(Path::<4, 4, 4>::new())
    .timestamp(12345)
    .payload_digest("some_hash")
    .payload_length(17)
    .build().unwrap();

assert_eq!(*entry.wdm_subspace_id(), "alfie");

pub fn prefilled_builder<E>(source: &E) -> EntryBuilder<MCL, MCC, MPL, N, S, PD>

where E: Entrylike<MCL, MCC, MPL, N, S, PD>, N: Clone, S: Clone, PD: Clone,

Creates a builder which is prefilled with the data from some other entry.

Use this function to create modified copies of entries.

Examples

use willow_data_model::prelude::*;

// Supplying all necessary data yields an entry.
let first_entry = Entry::builder()
    .namespace_id("family")
    .subspace_id("alfie")
    .path(Path::<4, 4, 4>::new())
    .timestamp(12345)
    .payload_digest("some_hash")
    .payload_length(17)
    .build().unwrap();

assert_eq!(*first_entry.wdm_payload_digest(), "some_hash");

let second_entry = Entry::prefilled_builder(&first_entry)
    .timestamp(67890)
    .payload_digest("another_hash")
    .payload_length(4)
    .build().unwrap();

assert_eq!(*second_entry.wdm_payload_digest(), "another_hash");

Trait Implementations

impl<'arbitrary, const MCL: usize, const MCC: usize, const MPL: usize, N: Arbitrary<'arbitrary>, S: Arbitrary<'arbitrary>, PD: Arbitrary<'arbitrary>> Arbitrary<'arbitrary> for Entry<MCL, MCC, MPL, N, S, PD>

fn arbitrary(u: &mut Unstructured<'arbitrary>) -> Result<Self>

Generate an arbitrary value of Self from the given unstructured data.

fn arbitrary_take_rest(u: Unstructured<'arbitrary>) -> Result<Self>

Generate an arbitrary value of Self from the entirety of the given unstructured data.

fn size_hint(depth: usize) -> (usize, Option<usize>)

Get a size hint for how many bytes out of an Unstructured this type needs to construct itself.

fn try_size_hint( depth: usize, ) -> Result<(usize, Option<usize>), MaxRecursionReached>

Get a size hint for how many bytes out of an Unstructured this type needs to construct itself.

impl<const MCL: usize, const MCC: usize, const MPL: usize, N: Clone, S: Clone, PD: Clone> Clone for Entry<MCL, MCC, MPL, N, S, PD>

fn clone(&self) -> Entry<MCL, MCC, MPL, N, S, PD>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<const MCL: usize, const MCC: usize, const MPL: usize, N, S, PD> Coordinatelike<MCL, MCC, MPL, S> for Entry<MCL, MCC, MPL, N, S, PD>

fn wdm_timestamp(&self) -> Timestamp

Returns the timestamp of self.

impl<const MCL: usize, const MCC: usize, const MPL: usize, N: Debug, S: Debug, PD: Debug> Debug for Entry<MCL, MCC, MPL, N, S, PD>

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

Formats the value using the given formatter.

impl<const MCL: usize, const MCC: usize, const MPL: usize, N, S, PD> Entrylike<MCL, MCC, MPL, N, S, PD> for Entry<MCL, MCC, MPL, N, S, PD>

fn wdm_namespace_id(&self) -> &N

Returns the namespace_id of self.

fn wdm_payload_length(&self) -> u64

Returns the payload_length of self.

fn wdm_payload_digest(&self) -> &PD

Returns the payload_digest of self.

impl<const MCL: usize, const MCC: usize, const MPL: usize, N: Hash, S: Hash, PD: Hash> Hash for Entry<MCL, MCC, MPL, N, S, PD>

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<const MCL: usize, const MCC: usize, const MPL: usize, N, S, PD> Keylike<MCL, MCC, MPL, S> for Entry<MCL, MCC, MPL, N, S, PD>

fn wdm_subspace_id(&self) -> &S

Returns the subspace_id of self.

fn wdm_path(&self) -> &Path<MCL, MCC, MPL>

Returns the path of self.

impl<const MCL: usize, const MCC: usize, const MPL: usize, N: Ord, S: Ord, PD: Ord> Ord for Entry<MCL, MCC, MPL, N, S, PD>

fn cmp(&self, other: &Entry<MCL, MCC, MPL, N, S, PD>) -> 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,

Restrict a value to a certain interval.

impl<const MCL: usize, const MCC: usize, const MPL: usize, N: PartialEq, S: PartialEq, PD: PartialEq> PartialEq for Entry<MCL, MCC, MPL, N, S, PD>

fn eq(&self, other: &Entry<MCL, MCC, MPL, N, S, PD>) -> 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<const MCL: usize, const MCC: usize, const MPL: usize, N: PartialOrd, S: PartialOrd, PD: PartialOrd> PartialOrd for Entry<MCL, MCC, MPL, N, S, PD>

fn partial_cmp( &self, other: &Entry<MCL, MCC, MPL, N, S, PD>, ) -> Option<Ordering>

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

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

Tests less than (for self and other) and is used by the < operator.

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

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

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

Tests greater than (for self and other) and is used by the > operator.

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

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

impl<const MCL: usize, const MCC: usize, const MPL: usize, N: Eq, S: Eq, PD: Eq> Eq for Entry<MCL, MCC, MPL, N, S, PD>

impl<const MCL: usize, const MCC: usize, const MPL: usize, N, S, PD> StructuralPartialEq for Entry<MCL, MCC, MPL, N, S, PD>