moqtap-trace

Event model, trace I/O, derived metrics.

crates.io | API docs

What it does

moqtap-trace defines the TraceEvent struct and the .moqtrace file format. It also computes derived metrics from event streams.

TraceEvent

pub struct TraceEvent {
    pub timestamp_us: u64,
    pub direction: Direction,
    pub message: ControlMessage,
    pub raw_bytes: Vec<u8>,
    pub warnings: Vec<ParseWarning>,
    pub quic_stats: Option<QuicStats>,
}

Derived metrics

• Control message RTT — request/response pairing by request ID
• Object arrival rate — objects per second per track
• Inter-object gap — time between consecutive objects
• Subscribe-to-first-object latency
• FETCH round-trip time

Trace file I/O

use moqtap_trace::{TraceWriter, TraceReader};

// Write events to a .moqtrace file
let mut writer = TraceWriter::new("session.moqtrace")?;
writer.write_event(&event)?;

// Read events from a file
let reader = TraceReader::open("session.moqtrace")?;
for event in reader {
    println!("{:?}", event?);
}