Struct Evidence 

pub struct Evidence {
    pub verdict: Verdict,
    pub checker: CheckerId,
    pub inputs: Vec<Digest>,
    pub signature: Signature,
    pub key: SigningKeyId,
    pub kind: EvidenceKind,
}

Re-exported so a consumer holding evidence does not also depend on boundgraph-core just for the types it is made of. ε — a signed verdict from a checker or a quorum.

Example

use boundgraph_core::{CheckerId, Digest, Evidence, EvidenceKind, Signature, SigningKeyId, Verdict};

let patch = Digest::of(b"the patch that was checked");

let ev = Evidence::new(
    Verdict::Pass,
    CheckerId::new("cargo-test", 1),
    vec![patch],
    Signature::from_bytes([0u8; 64]),
    SigningKeyId("host-key-1".into()),
    EvidenceKind::Deterministic,
);

assert!(ev.permits_commit());
// Evidence names exactly what it covers, so it cannot be reattached.
assert!(ev.covers(&patch));
assert!(!ev.covers(&Digest::of(b"some other patch")));

Fields

verdict: Verdict

The outcome.

checker: CheckerId

Which checker decided, and at what version.

inputs: Vec<Digest>

Digests of exactly what was checked.

This is what stops evidence being re-pointed at different data: a verdict only speaks about these inputs.

signature: Signature

Signature over the canonical encoding of every other field.

key: SigningKeyId

Which key signed.

kind: EvidenceKind

How the verdict was reached.

Implementations

impl Evidence

pub fn new( verdict: Verdict, checker: CheckerId, inputs: impl IntoIterator<Item = Digest>, signature: Signature, key: SigningKeyId, kind: EvidenceKind, ) -> Evidence

Construct evidence.

Inputs are sorted, so two verdicts over the same set of inputs share a digest regardless of the order the checker happened to list them.

pub fn permits_commit(&self) -> bool

Whether this evidence permits a state change to commit.

True only for Verdict::Pass.

pub fn covers(&self, digest: &Digest) -> bool

Whether this evidence actually speaks about the given input.

A commit must check this. Passing evidence about a different artefact is not permission to commit this one.

pub fn signing_payload(&self) -> Result<Vec<u8>, CanonicalError>

The bytes a signature is made over: everything except the signature.

Exposed so the signer (US-0802) and any verifier compute the same pre-image, rather than each deriving it and hoping they agree.

Trait Implementations

impl Clone for Evidence

fn clone(&self) -> Evidence

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Evidence

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Evidence

fn deserialize<__D>( __deserializer: __D, ) -> Result<Evidence, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for Evidence

fn eq(&self, other: &Evidence) -> bool

Equality operator ==.

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

Inequality operator !=.

impl Serialize for Evidence

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Evidence