Struct AuditCheckpoint 

pub struct AuditCheckpoint {
    pub checkpoint_id: Uuid,
    pub head: [u8; 32],
    pub entry_count: u64,
    pub head_event_id: Uuid,
    pub checkpoint_at: DateTime<Utc>,
    pub prev_checkpoint: Option<[u8; 32]>,
    pub verification_method: String,
    pub signature: Vec<u8>,
}

A signed commitment to the audit chain’s state at a point in time.

Stored in the audit_checkpoint keyspace keyed by <rfc3339>:<uuid>, matching the audit keyspace’s convention so an ascending walk is chronological.

Fields

checkpoint_id: Uuid

Stable identifier for this checkpoint.

head: [u8; 32]

entry_hash of the newest chainable envelope at checkpoint time.

entry_count: u64

Total chainable (v2+) envelopes written up to and including Self::head.

This is the field that makes truncation detectable: a log holding fewer chainable entries than a signed checkpoint claims has lost entries, and no amount of restamping fixes that without the signing key. Counting only chainable envelopes matters — pre-v2 rows are skipped by the verifier, so including them would make the count disagree with what verification can actually recount.

head_event_id: Uuid

event_id of the envelope at Self::head, so a verifier can locate the anchor point directly instead of recomputing the whole chain.

checkpoint_at: DateTime<Utc>

Wall-clock at checkpoint time.

prev_checkpoint: Option<[u8; 32]>

The previous checkpoint’s own Self::link_hash, or None for the first. Checkpoints chain too, so deleting a checkpoint is itself detectable — otherwise an adversary would simply drop the checkpoints that contradict a truncated log.

verification_method: String

verificationMethod URI of the key that signed this checkpoint (e.g. did:webvh:…#key-0). Recorded so a checkpoint stays verifiable across a key rotation: a verifier resolves this key from the community’s DID document history rather than assuming the current one.

signature: Vec<u8>

Ed25519 signature over [Self::signing_payload].

Implementations

impl AuditCheckpoint

pub fn sign(claim: CheckpointClaim, signing_key: &SigningKey) -> Self

Build and sign a checkpoint with signing_key.

verification_method must name the public key corresponding to signing_key in the community’s DID document — a verifier resolves it to check the signature.

pub fn claim(&self) -> CheckpointClaim

The claim this checkpoint carries — the signed half of it.

pub fn verify_signature(&self, public_key: &[u8]) -> bool

Verify the signature against public_key (32 raw Ed25519 bytes).

Returns false for a malformed key or signature as well as a genuine mismatch — from the verifier’s point of view those are the same finding: this checkpoint does not prove anything.

pub fn link_hash(&self) -> [u8; 32]

This checkpoint’s own hash — what the next one’s Self::prev_checkpoint points at.

Covers the signature as well as the claim, so swapping a valid signature for a different valid signature over the same claim still breaks the link.

pub fn storage_key(&self) -> Vec<u8>

Storage key: <rfc3339>:<checkpoint_id>, so an ascending prefix walk is chronological (matching the audit keyspace’s convention).

Trait Implementations

impl Clone for AuditCheckpoint

fn clone(&self) -> AuditCheckpoint

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AuditCheckpoint

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for AuditCheckpoint

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for AuditCheckpoint

impl PartialEq for AuditCheckpoint

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for AuditCheckpoint

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for AuditCheckpoint