Struct quinn::Connection

pub struct Connection(_);

A QUIC connection.

If all references to a connection (including every clone of the Connection handle, streams of incoming streams, and the various stream types) have been dropped, then the connection will be automatically closed with an error_code of 0 and an empty reason. You can also close the connection explicitly by calling Connection::close().

May be cloned to obtain another handle to the same connection.

Implementations

impl Connection

pub fn open_uni(&self) -> OpenUni

Initiate a new outgoing unidirectional stream.

Streams are cheap and instantaneous to open unless blocked by flow control. As a consequence, the peer won’t be notified that a stream has been opened until the stream is actually used.

pub fn open_bi(&self) -> OpenBi

Initiate a new outgoing bidirectional stream.

Streams are cheap and instantaneous to open unless blocked by flow control. As a consequence, the peer won’t be notified that a stream has been opened until the stream is actually used.

pub fn close(&self, error_code: VarInt, reason: &[u8])

Close the connection immediately.

Pending operations will fail immediately with ConnectionError::LocallyClosed. Delivery of data on unfinished streams is not guaranteed, so the application must call this only when all important communications have been completed, e.g. by calling finish on outstanding SendStreams and waiting for the resulting futures to complete.

error_code and reason are not interpreted, and are provided directly to the peer.

reason will be truncated to fit in a single packet with overhead; to improve odds that it is preserved in full, it should be kept under 1KiB.

pub fn send_datagram(&self, data: Bytes) -> Result<(), SendDatagramError>

Transmit data as an unreliable, unordered application datagram

Application datagrams are a low-level primitive. They may be lost or delivered out of order, and data must both fit inside a single QUIC packet and be smaller than the maximum dictated by the peer.

pub fn max_datagram_size(&self) -> Option<usize>

Compute the maximum size of datagrams that may be passed to send_datagram().

Returns None if datagrams are unsupported by the peer or disabled locally.

This may change over the lifetime of a connection according to variation in the path MTU estimate. The peer can also enforce an arbitrarily small fixed limit, but if the peer’s limit is large this is guaranteed to be a little over a kilobyte at minimum.

Not necessarily the maximum size of received datagrams.

pub fn remote_address(&self) -> SocketAddr

The peer’s UDP address

If ServerConfig::migration is true, clients may change addresses at will, e.g. when switching to a cellular internet connection.

pub fn local_ip(&self) -> Option<IpAddr>

The local IP address which was used when the peer established the connection

This can be different from the address the endpoint is bound to, in case the endpoint is bound to a wildcard address like 0.0.0.0 or ::.

This will return None for clients.

Retrieving the local IP address is currently supported on the following platforms:

• Linux

On all non-supported platforms the local IP address will not be available, and the method will return None.

pub fn rtt(&self) -> Duration

Current best estimate of this connection’s latency (round-trip-time)

pub fn stats(&self) -> ConnectionStats

Returns connection statistics

pub fn congestion_state(&self) -> Box<dyn Controller>

Current state of the congestion control algorithm, for debugging purposes

pub fn handshake_data(&self) -> Option<Box<dyn Any>>

Parameters negotiated during the handshake

Guaranteed to return Some on fully established connections or after Connecting::handshake_data() succeeds. See that method’s documentations for details on the returned value.

pub fn peer_identity(&self) -> Option<Box<dyn Any>>

Cryptographic identity of the peer

The dynamic type returned is determined by the configured Session. For the default rustls session, the return value can be downcast to a Vec<rustls::Certificate>

pub fn stable_id(&self) -> usize

A stable identifier for this connection

Peer addresses and connection IDs can change, but this value will remain fixed for the lifetime of the connection.

pub fn export_keying_material(
    &self,
    output: &mut [u8],
    label: &[u8],
    context: &[u8]
) -> Result<(), ExportKeyingMaterialError>

Derive keying material from this connection’s TLS session secrets.

When both peers call this method with the same label and context arguments and output buffers of equal length, they will get the same sequence of bytes in output. These bytes are cryptographically strong and pseudorandom, and are suitable for use as keying material.

See RFC5705 for more information.

pub fn set_max_concurrent_uni_streams(&self, count: VarInt)

Modify the number of remotely initiated unidirectional streams that may be concurrently open

No streams may be opened by the peer unless fewer than count are already open. Large counts increase both minimum and worst-case memory consumption.

pub fn set_receive_window(&self, receive_window: VarInt)

See proto::TransportConfig::receive_window()

pub fn set_max_concurrent_bi_streams(&self, count: VarInt)

Modify the number of remotely initiated bidirectional streams that may be concurrently open

No streams may be opened by the peer unless fewer than count are already open. Large counts increase both minimum and worst-case memory consumption.

Trait Implementations

impl Clone for Connection

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Connection

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

Formats the value using the given formatter.