Module session 

Per-connection proxy session — forwards streams between client and relay.

Re-exports

use std::future::Future; 🔒

use std::pin::Pin; 🔒

use std::sync::atomic::AtomicBool; 🔒

use std::sync::atomic::AtomicU64; 🔒

use std::sync::atomic::Ordering; 🔒

use std::sync::Arc; 🔒

use std::sync::Mutex; 🔒

use std::time::Duration; 🔒

use std::time::Instant; 🔒

use bytes::Bytes; 🔒

use bytes::BytesMut; 🔒

use tokio::sync::mpsc; 🔒

use tokio::sync::watch; 🔒

use tokio::task::JoinSet; 🔒

use tokio_util::sync::CancellationToken; 🔒

use moqtap_client::transport::quic::QuicTransport; 🔒

use moqtap_client::transport::RecvStream; 🔒

use moqtap_client::transport::SendStream; 🔒

use moqtap_client::transport::Transport; 🔒

use moqtap_client::transport::TransportError; 🔒

use moqtap_codec::dispatch::AnyControlMessage; 🔒

use moqtap_codec::dispatch::AnyDatagramHeader; 🔒

use moqtap_codec::varint::VarInt; 🔒

use moqtap_codec::version::DraftVersion; 🔒

use crate::action::Action; 🔒

use crate::action::EgressConfig; 🔒

use crate::action::Interest; 🔒

use crate::action::StreamEnd; 🔒

use crate::capability::fetch_group_order_is_needed; 🔒

use crate::capability::ActionKind; 🔒

use crate::capability::Capabilities; 🔒

use crate::capability::Site; 🔒

use crate::control::AbortOnDrop; 🔒

use crate::control::ControlAttachment; 🔒

use crate::control::ControlLeg; 🔒

use crate::control::ControlPlane; 🔒

use crate::control::SessionCommand; 🔒

use crate::control::StreamCommand; 🔒

use crate::control::StreamRegistry; 🔒

use crate::control::COMMAND_QUEUE_DEPTH; 🔒

use crate::egress; 🔒

use crate::egress::CloseOrigin; 🔒

use crate::egress::DrainOutcome; 🔒

use crate::egress::EgressGauge; 🔒

use crate::egress::PendingQueue; 🔒

use crate::egress::SessionCloser; 🔒

use crate::error::ProxyError; 🔒

use crate::event::DataStreamHeaderKind; 🔒

use crate::event::Effect; 🔒

use crate::event::ImpairmentKind; 🔒

use crate::event::ProxyEvent; 🔒

use crate::event::SessionId; 🔒

use crate::event::ShapeOutcome; 🔒

use crate::exec; 🔒

use crate::exec::DeferredEffects; 🔒

use crate::exec::Plan; 🔒

use crate::exec::StreamSite; 🔒

use crate::framer::FetchGroupOrders; 🔒

use crate::framer::FramerConfig; 🔒

use crate::framer::FramerOut; 🔒

use crate::framer::ObjectFramer; 🔒

use crate::hook::FrameCtx; 🔒

use crate::hook::ObjectCtx; 🔒

use crate::hook::ProxyHook; 🔒

use crate::hook::StreamCtx; 🔒

use crate::instrument::Counters; 🔒

use crate::instrument::Recorder; 🔒

use crate::observer::ProxyObserver; 🔒

use crate::parser::control::ControlStreamParser; 🔒

use crate::parser::control::ParseResult; 🔒

use crate::parser::control::ParsedItem; 🔒

use crate::shape::Acquire; 🔒

use crate::shape::Admission; 🔒

use crate::shape::Class; 🔒

use crate::shape::Scheduler; 🔒

use crate::shape::ShapeProfile; 🔒

use crate::shape::ShapeRecorder; 🔒

use crate::shape::ShapeStats; 🔒

use crate::shape::StreamKey; 🔒

use crate::transport; 🔒

use crate::transport::TransportInstaller; 🔒

use crate::transport::TransportProfile; 🔒

use crate::types::DataStreamType; 🔒

use crate::types::Leg; 🔒

use crate::types::ProxySide; 🔒

Structs

CachedShaper 🔒

What SessionShaper keeps behind its lock.

ControlFrameWalker 🔒

Where the message boundaries are on a control stream being forwarded verbatim.

ForwardCtx 🔒

Shared context for forwarding helpers, avoiding repeated parameter lists.

NegotiatedProtocol 🔒

The relay’s WT-Protocol: as sent, and the identifier inside it when it is a well-formed sf-string.

PeekedRecv 🔒

A receive stream with bytes already taken off it.

ProxySession

A proxy session that forwards traffic between a client and an upstream relay. One session is created per accepted client connection.

ProxySessionConfig

Configuration for a proxy session’s upstream connection.

SessionDraft 🔒

The draft this session frames with, and the one place every task reads it from.

SessionShaper 🔒

One session’s shaper, and the proxy profile it watches.

ShapedStream 🔒

Which stream a shaped release is happening on, for the events it owes.

SkipVerification 🔒

TLS certificate verifier that skips all verification (testing only).

StopWatcher 🔒

A destination-side STOP_SENDING watcher, hoisted once per forwarded stream and used as a fourth tokio::select! branch.

StreamState 🔒

The deferred-write state of one stream direction, plus the two facts every teardown helper needs about it.

Upstream 🔒

A dialled relay, with the WebTransport protocol it chose.

Enums

ClientConn 🔒

Where a session’s client comes from.

DraftPeek 🔒

What peek_draft made of a control stream’s opening bytes.

DraftSource 🔒

Where a session’s draft came from, ranked by how much it is worth.

Flow 🔒

Whether a stream direction may keep running after a helper returned.

HeaderStep 🔒

What one more header byte told ControlFrameWalker.

Source 🔒

What one poll of the source stream saw.

StreamRequest 🔒

What a data stream’s task does with a control-plane request.

UniStreamKind 🔒

What a unidirectional stream’s leading varint says the stream is.

UpstreamTransportType

The transport type for upstream relay connections.

Constants

CONTROL_STREAM_TYPE 🔒

The unidirectional stream type that marks a control stream on the drafts control_plane_is_unidirectional names, and the SETUP message type on the same drafts. They are one number, 0x2F00.

DETECT_BUF_MAX 🔒

The most bytes a control stream is buffered for while its first message is peeked at.

DRAFT_SETTLE_WINDOW 🔒

How long a task that needs the session’s draft waits for the control stream to name one before running on the draft the session started with.

MAX_CONTROL_HEADER 🔒

The largest control-message header this crate can meet: an eight-byte type varint followed by an eight-byte length varint.

MAX_CONTROL_PAYLOAD 🔒

A declared control-message payload length above which ControlFrameWalker stops believing what it is reading.

MAX_UNI_TYPE_LEN 🔒

The most bytes a unidirectional stream’s type varint can occupy: nine, which is MoQT’s widest form from draft-17 (RFC 9000’s is eight).

Functions

action_kind 🔒

The ActionKind a returned Action will be reported as.

await_serialize_target 🔒

Hold this stream until target ends — StreamAction::SerializeAfter.

bidi_streams_carry_requests 🔒

Whether this draft puts requests on bidirectional streams of their own, so that a bidirectional stream beyond the control stream is a stream this proxy has to forward.

class_label 🔒

The label ProxyEvent::Shaped reports a class under.

classify_uni_stream 🔒

Read a unidirectional stream’s type varint and say what the stream is.

close_after_draining 🔒

Give this session’s egress queues drain to empty, then end it.

close_reason 🔒

Who closed the session and with what, when a close was requested.

control_event 🔒

The observer event one parsed control frame produces.

control_length_is_bounded 🔒

Whether MAX_CONTROL_PAYLOAD bounds a control message length this draft frames as a varint. See that constant for why 07-10 are bounded and 23 is not.

control_plane_is_unidirectional 🔒

Whether this draft carries control messages on a pair of unidirectional streams, making a bidirectional stream a request stream rather than the control stream.

data_stream_request 🔒

Interpret one request delivered to a data stream’s task.

datagram_is_status 🔒

Whether a decoded datagram header carries an Object Status.

datagram_payload_start 🔒

Where a decoded datagram’s payload starts.

detect_stream_type 🔒

Determine the data stream type from the first varint on the stream.

drain_pending 🔒

Flush anything the hook deferred, honouring its release times, as a race against session cancellation.

egress_side 🔒

The egress side paired with an ingress side.

emit_parsed_frames 🔒

Feed bytes to the control parser and emit observer events for any completed frames.

forward_control_stream 🔒

Forward the control stream on the drafts whose control stream is the first client-initiated bidirectional stream — drafts 07 through 16.

forward_datagrams 🔒

Forward datagrams from source to destination.

forward_mutated_frames 🔒

Feed bytes into the capturing control parser, then execute the hook’s decision on each completed frame.

forward_request_streams 🔒

Forward bidirectional request streams, on the drafts where that is what a bidirectional stream is — see control_plane_is_unidirectional.

forward_undefined_bidi_streams 🔒

Forward, unread, the bidirectional streams a draft does not define: every one after the control stream on drafts 07-15. The relay answers them as its draft says.

forward_uni_streams 🔒

Forward unidirectional streams from source to destination.

is_connection_level 🔒

Whether a send_datagram failure ends the session.

is_mirrored_teardown 🔒

Whether a pipe error is an abnormal teardown the proxy already mirrored and reported as ProxyEvent::StreamReset.

new_capturing_control_parser 🔒

Build a capturing control parser and count it.

new_control_parser 🔒

Build a non-capturing control parser and count it.

note_fetch_order 🔒

File the Group Order a FETCH asked for, from the bytes leaving the proxy.

note_fetch_orders 🔒

File the Group Order every FETCH in this batch asked for.

observe_source 🔒

Observe the source stream, whatever the egress queue is doing.

paired_ingress_side 🔒

The ingress side of the other direction of the same stream.

peek_draft 🔒

Try to name the concrete draft by peeking at the first SETUP message on a control stream.

pipe_control 🔒

Pipe one direction of a stream carrying MoQT control-message framing.

pipe_control_mutating 🔒

Parse-then-forward control stream pipe.

pipe_control_passthrough 🔒

Forward-first control stream pipe.

pipe_data 🔒

Pipe a unidirectional data stream.

pipe_data_framed 🔒

Forward a unidirectional data stream through the object framer.

pipe_data_passthrough 🔒

Forward a unidirectional data stream without interpreting it.

propagate_reset 🔒

Mirror a source-side read failure onto the destination stream.

propagate_stop 🔒

Mirror a destination-side write failure onto the source stream.

pump_control_leg 🔒

Hand one control leg’s requests to the stream that turned out to be that direction’s control stream.

reject_pending 🔒

Answer an unanswered request with 404; a connected client is left to its owner.

release_due_units 🔒

Write every unit whose release time has arrived, in order.

report_refused_frames 🔒

Report the control frames the decoder refused in one feed.

report_request_stream_end 🔒

Report a request-stream pipe that ended badly, on the same terms forward_uni_streams reports one.

report_shaping 🔒

Emit whatever a shaped release decided, if anything.

report_unconfirmed 🔒

Report whatever a teardown drain could not vouch for, once.

request_streams_beside_the_control_stream 🔒

The client-to-relay loop for bidirectional streams beside a bidirectional control stream: draft-16’s request streams (see bidi_streams_carry_requests), or on 07-15 streams the draft does not define.

run_stream_end 🔒

Call ProxyHook::on_stream_end and execute what it returns.

same_classes 🔒

Whether profile names exactly classes, in the same order.

serve_session_commands 🔒

Serve one session’s control-plane requests until the session ends.

setup_rank 🔒

Which DraftSource a SETUP peeked at on side carries.

stop_error 🔒

The one StopWatcher outcome that ends a stream.

stream_reset_code_defined 🔒

Whether the draft defines a stream-reset error code vocabulary.

synthesized_reset_code 🔒

The application error code to reset a forwarded data stream with when the source read failed for a reason that is not a peer RESET_STREAM.

varint_len 🔒

Determine the encoded length of a QUIC varint from its first byte.

version_varint_to_draft 🔒

Convert an on-wire MoQT version varint (0xff000000 + draft) to a DraftVersion, or None if the value is malformed or unsupported.

write_in_order 🔒

Write bytes the hook was never shown, keeping wire order — on an unshaped stream.

write_with_injections 🔒

Write one forwarded chunk with any held injections spliced in at split.

Type Aliases

StoppedFuture 🔒

A boxed SendStream::stopped() future.