Struct Session 

pub struct Session { /* private fields */ }

One session with one pilot: a WebTransport session over QUIC, or, when no direct path connected, the same datagrams and control stream carried through the cloud relay. The engine sees one type either way; only Session::kind tells them apart, and it is reported to the pilot rather than hidden.

Implementations

impl Session

pub async fn relay( id: u64, url: &str, session_id: &str, token: &str, send_buffer_capacity: usize, ) -> Result<Session>

Open a relayed session through the cloud (ADR 0010). url, session_id and token come from the signal server’s relay-open. Resolves once the relay has paired this socket with the pilot’s, or fails.

pub fn session_id(&self) -> u64

pub fn kind(&self) -> SessionKind

pub fn remote_addr(&self) -> Option<SocketAddr>

The pilot’s address for a direct session; None through the relay, where the only peer address is the cloud’s.

pub fn max_datagram_size(&self) -> usize

Largest payload send_datagram currently accepts (path MTU minus QUIC and WebTransport framing). Changes as DPLPMTUD converges.

pub fn send_buffer_space(&self) -> usize

Bytes the send buffer can take right now without dropping anything. Compare a whole frame’s size against this before sending its first chunk.

pub fn send_buffer_queued(&self) -> usize

Payload bytes queued in the datagram send buffer and not yet packetised: the backlog that admission control measures against the QoS profile’s threshold. Everything counted here is latency the pilot has not seen yet.

quinn exposes only the free space (capacity minus queued payload, minus one bookkeeping constant), so this is the complement; the constant makes it read a few dozen bytes high, which is nothing against a frame.

pub fn send_datagram(&self, payload: Bytes) -> Result<(), SendError>

Queue one datagram. Never blocks, never evicts queued datagrams.

pub fn take_datagrams(&self) -> Option<Receiver<Bytes>>

Inbound datagrams (WebTransport prefix stripped). Can be taken once.

pub async fn control(&self) -> Option<(ControlReader, ControlWriter)>

The first bidirectional stream the pilot opens — the control stream. Resolves once the pilot has opened it; None if the session ends first.

pub fn stats(&self) -> PathStats

pub fn close(&self, code: u32, reason: &str)

pub async fn closed(&self)

Resolves when the connection is gone.