Struct FederationNonceCache 

pub struct FederationNonceCache { /* private fields */ }

v0.7.0 #922 — per-peer bounded FIFO cache of (peer_id, nonce).

Implementations

impl FederationNonceCache

pub fn new() -> Self

Fresh empty cache. In-memory only — the cache resets on every daemon restart. Prefer Self::new_with_db_persistence in production: pre-#1255 the in-memory-only cache opened a replay window on every restart.

pub fn new_with_db_persistence(db_path: impl Into<PathBuf>) -> Result<Self>

#1255 (MED, 2026-05-25) — persistence-enabled constructor.

Opens the ai-memory sqlite DB at db_path (runs migrations to ensure the federation_nonce_cache table is present), rehydrates the in-memory cache from the persisted rows (oldest last_touch first so the in-process LRU ordering matches the on-disk order), and arms the cache so every subsequent Fresh fingerprint is persisted to disk.

Construction errors out if the DB cannot be opened or migrated — operators want loud failure here, not a silent fallback to in-memory mode that re-opens the replay window.

Errors

Returns an error if the DB cannot be opened or the load query fails.

pub fn record_and_check(&self, peer_id: &str, nonce: &str) -> ReplayDecision

Check + record (peer_id, nonce).

pub fn peer_evictions_since_boot(&self) -> u64

v0.7.0 #1038 — cumulative number of peer-slot evictions (outer LRU). Non-zero means peer churn caused the outer HashMap to hit FEDERATION_NONCE_MAX_PEERS and drop an older peer’s slot. Operators page on sustained growth.

pub fn peer_count(&self) -> usize

Distinct peers with at least one cached fingerprint.

pub fn len_for_peer(&self, peer_id: &str) -> usize

Cached fingerprints for peer_id.

Trait Implementations

impl Debug for FederationNonceCache

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

Formats the value using the given formatter.

impl Default for FederationNonceCache

fn default() -> FederationNonceCache

Returns the “default value” for a type.