Struct StreamEndpoint 

pub struct StreamEndpoint<'a> { /* private fields */ }

The per-peer streaming registry (SPEC §3): it multiplexes many concurrent streams to ONE peer, bounds their count (MAX_CONCURRENT_STREAMS), seals every outbound frame with a fresh ephemeral, and opens + fully verifies every inbound frame — RESETting a stream on any failed verify (gate items DIG-Network/dig_ecosystem#1162).

One endpoint’s identity key both SEALS our outbound frames (as sender) and OPENS the peer’s inbound frames (as recipient) — the ONE BLS12-381 identity key (SPEC §5.1).

Implementations

impl<'a> StreamEndpoint<'a>

pub fn new( identity_sk: &'a SecretKey, local_did: Bytes32, local_epoch: u32, peer_did: Bytes32, peer_pub: &'a [u8; 48], message_type: u32, ) -> Self

A new endpoint for streams to one peer, using MAX_CONCURRENT_STREAMS as the cap.

identity_sk is our ONE BLS12-381 identity key; peer_pub is the peer’s 48-byte G1 identity key. message_type is the SPEC §4 type every frame carries.

pub fn with_max_concurrent(self, max: usize) -> Self

Override the per-peer concurrent-stream cap (SPEC §3), e.g. for a higher-capacity relay endpoint or a tighter test boundary. Defaults to MAX_CONCURRENT_STREAMS.

pub fn stream_count(&self) -> usize

The number of live streams to this peer.

pub fn session(&self, correlation_id: Bytes32) -> Option<&StreamSession>

Read-only access to a live session (for inspection/testing).

pub fn open( &mut self, correlation_id: Bytes32, recv_window: u32, now_ms: u64, expires_at: u64, ) -> Result<DigMessageEnvelope>

Open a new outbound stream, advertising recv_window credits for the peer→us direction (SPEC §3). Returns the sealed OPEN envelope to send.

Errors

MessageError::StreamLimit if we already hold MAX_CONCURRENT_STREAMS streams; MessageError::StreamProtocol if correlation_id is already in use; plus any seal error.

pub fn open_ack( &mut self, correlation_id: Bytes32, recv_window: u32, now_ms: u64, expires_at: u64, ) -> Result<DigMessageEnvelope>

Complete a responder handshake, advertising recv_window credits for the peer→us direction. Returns the sealed OPEN_ACK envelope.

Errors

MessageError::StreamProtocol for an unknown stream or an illegal handshake position; plus any seal error.

pub fn send_data( &mut self, correlation_id: Bytes32, payload: &[u8], now_ms: u64, expires_at: u64, ) -> Result<DigMessageEnvelope>

Send one DATA chunk on an established stream, consuming one credit (SPEC §3). Returns the sealed DATA envelope.

Errors

MessageError::StreamProtocol for an unknown stream, a closed direction, or exhausted credit (backpressure); plus any seal/compression error.

pub fn grant_credit( &mut self, correlation_id: Bytes32, n: u32, now_ms: u64, expires_at: u64, ) -> Result<DigMessageEnvelope>

Grant the peer n more DATA credits (SPEC §3 backpressure). Returns the sealed CREDIT envelope.

Errors

MessageError::StreamProtocol for an unknown or not-yet-established stream; plus any seal error.

pub fn close( &mut self, correlation_id: Bytes32, now_ms: u64, expires_at: u64, ) -> Result<DigMessageEnvelope>

Half-close our sending direction (SPEC §3). Returns the sealed CLOSE envelope; the stream is dropped once BOTH directions are closed.

Errors

MessageError::StreamProtocol for an unknown or already-closed direction; plus any seal error.

pub fn reset( &mut self, correlation_id: Bytes32, now_ms: u64, expires_at: u64, ) -> Result<DigMessageEnvelope>

Abort a stream immediately (SPEC §3 cancel). Returns the sealed RESET envelope and drops the stream.

Errors

MessageError::StreamProtocol for an unknown stream; plus any seal error.

pub fn accept( &mut self, envelope: &DigMessageEnvelope, resolve_sender_pub: impl Fn(Bytes32, u32) -> Option<[u8; 48]>, now_ms: u64, ) -> Result<StreamAccept>

Open + fully verify an inbound frame and drive the state machine (SPEC §3). On success returns a verified StreamEvent; on ANY failed verify or protocol violation returns StreamAccept::Dropped — a bad/unauthenticated/non-actionable frame silently discarded (a live session is left untouched); or, ONLY for a state-machine violation by the AUTHENTICATED peer on a KNOWN stream (or the concurrent-stream cap), StreamAccept::Reset — a sealed RESET the caller sends. A RESET is NEVER emitted for unauthenticated or duplicate input, so the untrusted relay (§5.4) cannot provoke a RESET reflection storm or replay-teardown (SPEC §3, gate item #1162).

resolve_sender_pub maps (peer DID, epoch) to the peer’s 48-byte G1 key (usually the endpoint’s own peer_pub); now_ms is our wall clock for the freshness + expiry checks.

Errors

Only a failure to SEAL the RESET response (on the authenticated-violation path) propagates as Err; a rejected inbound frame is the non-error StreamAccept::Dropped/StreamAccept::Reset outcome.