Struct PexEngine 

pub struct PexEngine { /* private fields */ }

The transport-agnostic PEX engine (SPEC Appendix A). One instance per participant; it multiplexes all of that participant’s links.

Implementations

impl PexEngine

pub fn new(cfg: PexConfig) -> Self

Create an engine from cfg.

pub fn upsert_known(&mut self, entry: PeerEntry)

Add or update a first-hand-known peer in the advertise set (SPEC §8.1, §9.3). The caller supplies the honest via + a fresh last_seen; the Provenance type structurally forbids a "pex" provenance, so a PEX-learned entry can never be re-advertised unverified. The change surfaces as added in the next tick delta on each link.

pub fn remove_known(&mut self, peer_id: &str)

Remove a peer from the advertise set — it disconnected or went stale (SPEC §9.3). It surfaces as dropped in the next delta on links that were told it.

pub fn link_up(&mut self, peer_id: &str, now_ms: u64) -> Vec<PexMessage>

A link came up: register it and produce our outgoing direction — the pex_handshake followed (back-to-back) by the pex_snapshot of our current first-hand set (SPEC §5.1, §6.1). Write the returned messages on our sending stream. Preserves any receiver-side state if the link already exists (e.g. an inbound message arrived first).

pub fn link_down(&mut self, peer_id: &str)

A link went down: discard all per-link state, and unlist it as the source of any current hints (SPEC §5.5, §9.2). A new connection starts fresh.

pub fn on_message( &mut self, peer_id: &str, msg: PexMessage, now_ms: u64, ) -> PexOutcome

Feed one decoded inbound message from peer_id. Returns replies to send + events to act on. A malformed entry inside a valid message is skipped silently; a malformed message / rate / oversize / state violation is discarded with a strike (SPEC §7.3, §11.2).

pub fn record_violation( &mut self, peer_id: &str, code: PexErrorCode, _now_ms: u64, ) -> PexOutcome

Record a transport-detected violation the engine could not see itself: a frame-size overrun (Oversized) or an undecodable/malformed frame (BadMessage) — SPEC §7.2, §7.3. Counts a strike and mutes at the limit, exactly like an engine-detected violation.

pub fn tick(&mut self, now_ms: u64) -> Vec<(String, PexMessage)>

Drive the send cadence (call ~1/s). For each link whose effective interval has elapsed since its last data message and that has pending changes, emits a pex_delta (SPEC §4.4, §6). A delta with no changes is suppressed (empty deltas are never sent). Returns (peer_id, message) pairs to write to the matching links.

pub fn known_count(&self) -> usize

Number of peers in the first-hand advertise set.

pub fn link_count(&self) -> usize

Number of live links.

pub fn is_muted(&self, peer_id: &str) -> bool

Whether the incoming direction of peer_id’s link is muted (SPEC §5.2, §11.2).

pub fn strikes(&self, peer_id: &str) -> u32

The violation strike count on peer_id’s incoming direction (SPEC §11.2).

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

How many peer ids we have currently told peer_id’s link (told-state size, SPEC §9.1).

pub fn current_hint(&self, peer_id: &str) -> Option<(&str, u64)>

The current deduplicated hint for peer_id (SPEC §9.2): (source link, last_seen), if any.

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

How many peer_ids peer_id’s link has told us are currently tracked in its received accumulator (SPEC §9.2, §11.3) — bounded by crate::caps::PEX_MAX_RECEIVED_PER_LINK.

pub fn hints_count(&self) -> usize

The total number of deduplicated hints currently held across all links (SPEC §9.2, §11.3) — bounded by crate::caps::PEX_MAX_HINTS.

Trait Implementations

impl Debug for PexEngine

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

Formats the value using the given formatter.