fix: preserve bound participant identity in observer

cai

2026-08-08 386bc138d82933123189fdbc8d856a1fae5feccf

 src/main.rs

@@ -30,7 +30,7 @@
    options::TrackPublishOptions,
    prelude::{
        DataPacket, LocalAudioTrack, LocalTrack, ParticipantIdentity, RemoteAudioTrack,
        RemoteTrack, Room, RoomEvent, RoomOptions,
        RemoteParticipant, RemoteTrack, Room, RoomEvent, RoomOptions,
    },
};
use reqwest::Client;
@@ -737,6 +737,10 @@
    })
}

fn is_bound_user_participant(identity: &str, expected: Option<&str>) -> bool {
    expected.is_none_or(|value| identity == value)
}

async fn observe_user_audio_events(
    mut events: UnboundedReceiver<RoomEvent>,
    call_id: String,
@@ -771,25 +775,15 @@
                publication: _,
                participant,
            } => {
                if user_participant_identity
                    .as_deref()
                    .is_some_and(|expected| participant.identity().to_string() != expected)
                {
                if !is_bound_user_participant(
                    &participant.identity().to_string(),
                    user_participant_identity.as_deref(),
                ) {
                    warn!(call_id = %call_id, trace_id = %trace_id,
                        metadata_status = "wrong_participant",
                        "runtime helper ignored non-user audio participant");
                    continue;
                }
                let ingress_metadata =
                    match AudioIngressMetadata::from_participant(&participant.attributes()) {
                        Ok(value) => value,
                        Err(reason) => {
                            warn!(call_id = %call_id, trace_id = %trace_id,
                            metadata_status = "invalid", reason = reason,
                            "runtime helper ignored invalid audio ingress metadata");
                            None
                        }
                    };
                let participant_alias = redact(&participant.identity().to_string());
                let track_sid_alias = redact(&track.sid().to_string());
                let track_name = track.name();
@@ -801,9 +795,6 @@
                    track_sid_alias = %track_sid_alias,
                    track_name = %track_name,
                    track_source = %track_source,
                    metadata_status = if ingress_metadata.is_some() { "bound" } else { "absent" },
                    metadata_source = ingress_metadata.as_ref().map(|_| "controlled_fixture"),
                    metadata_sequence_present = ingress_metadata.is_some(),
                    "runtime helper user_track_subscribed"
                );
                spawn_user_audio_frame_observer(
@@ -818,6 +809,8 @@
                    turn_bridge_config.clone(),
                    http.clone(),
                    sink.clone(),
                    user_participant_identity.clone(),
                    participant,
                );
            }
            RoomEvent::TrackSubscribed {
@@ -2929,6 +2922,8 @@
    turn_bridge_config: TurnBridgeConfig,
    http: Client,
    sink: Arc<BotAudioOutputSink>,
    expected_participant_identity: Option<String>,
    participant: RemoteParticipant,
) -> JoinHandle<()> {
    tokio::spawn(async move {
        let mut stream = NativeAudioStream::new(
@@ -3007,6 +3002,7 @@
            None
        };
        let mut realtime_asr_upload: Option<RealtimeAsrUpload> = None;
        let mut last_fixture_sequence: Option<String> = None;

        while let Some(drained) = frame_rx.recv().await {
            let frame = drained.frame;
@@ -3040,8 +3036,11 @@

            if let Some(vad) = simple_vad.as_mut() {
                if vad_enabled_gate.load(Ordering::Acquire) {
                    let was_in_speech = vad.in_speech;
                    let turn = vad.observe_frame(
                    let participant_identity = participant.identity().to_string();
                    let (was_in_speech, is_in_speech, turn) = observe_bound_participant_frame(
                        &participant_identity,
                        expected_participant_identity.as_deref(),
                        vad,
                        &call_id,
                        &trace_id,
                        &participant_alias,
@@ -3049,41 +3048,15 @@
                        frame_count,
                        elapsed_ms,
                        &frame,
                        http.clone(),
                        turn_bridge_config.realtime_asr_config(),
                        || participant.attributes(),
                        &mut realtime_asr_upload,
                        &mut last_fixture_sequence,
                        turn_bridge_config.asr_realtime_enabled,
                    );
                    let is_in_speech = vad.in_speech;

                    if !was_in_speech && is_in_speech {
                        let turn_id = format!("turn-{:04}", vad.turn_index);
                        match RealtimeAsrUpload::start(
                            http.clone(),
                            turn_bridge_config.realtime_asr_config(),
                            &call_id,
                            &trace_id,
                            &turn_id,
                            &vad.speech_samples,
                            ingress_metadata.as_ref(),
                        ) {
                            Ok(upload) => {
                                info!(
                                    call_id = %call_id,
                                    trace_id = %trace_id,
                                    turn_id = %turn_id,
                                    "runtime helper asr_realtime_session_started"
                                );
                                realtime_asr_upload = Some(upload);
                            }
                            Err(error) if turn_bridge_config.asr_realtime_enabled => {
                                warn!(
                                    call_id = %call_id,
                                    trace_id = %trace_id,
                                    turn_id = %turn_id,
                                    error = %safe_error(&error.to_string()),
                                    "runtime helper asr_realtime_start_failed_fallback"
                                );
                            }
                            Err(_) => {}
                        }
                    } else if was_in_speech {
                    if was_in_speech {
                        let push_failed = realtime_asr_upload
                            .as_mut()
                            .and_then(|upload| upload.push_48k_samples(frame.data.as_ref()).err());
@@ -3200,6 +3173,166 @@
            "runtime helper user_audio_stream_ended"
        );
    })
}

fn observe_frame_and_start_session<F>(
    vad: &mut SimpleVad,
    call_id: &str,
    trace_id: &str,
    participant_alias: &str,
    track_sid_alias: &str,
    frame_count: u64,
    elapsed_ms: u64,
    frame: &AudioFrame<'_>,
    http: Client,
    config: RealtimeAsrConfig,
    read_attributes: F,
    upload_slot: &mut Option<RealtimeAsrUpload>,
    last_fixture_sequence: &mut Option<String>,
    realtime_enabled: bool,
) -> (bool, bool, Option<FinishedSpeechTurn>)
where
    F: FnOnce() -> std::collections::HashMap<String, String>,
{
    let was_in_speech = vad.in_speech;
    let turn = vad.observe_frame(
        call_id,
        trace_id,
        participant_alias,
        track_sid_alias,
        frame_count,
        elapsed_ms,
        frame,
    );
    let is_in_speech = vad.in_speech;
    if !was_in_speech && is_in_speech {
        start_realtime_session_for_new_speech(
            http,
            config,
            call_id,
            trace_id,
            vad,
            read_attributes,
            upload_slot,
            last_fixture_sequence,
            realtime_enabled,
        );
    }
    (was_in_speech, is_in_speech, turn)
}

fn observe_bound_participant_frame<F>(
    participant_identity: &str,
    expected_participant: Option<&str>,
    vad: &mut SimpleVad,
    call_id: &str,
    trace_id: &str,
    participant_alias: &str,
    track_sid_alias: &str,
    frame_count: u64,
    elapsed_ms: u64,
    frame: &AudioFrame<'_>,
    http: Client,
    config: RealtimeAsrConfig,
    read_attributes: F,
    upload_slot: &mut Option<RealtimeAsrUpload>,
    last_fixture_sequence: &mut Option<String>,
    realtime_enabled: bool,
) -> (bool, bool, Option<FinishedSpeechTurn>)
where
    F: FnOnce() -> std::collections::HashMap<String, String>,
{
    if !is_bound_user_participant(participant_identity, expected_participant) {
        return (vad.in_speech, vad.in_speech, None);
    }
    observe_frame_and_start_session(
        vad,
        call_id,
        trace_id,
        participant_alias,
        track_sid_alias,
        frame_count,
        elapsed_ms,
        frame,
        http,
        config,
        read_attributes,
        upload_slot,
        last_fixture_sequence,
        realtime_enabled,
    )
}

fn start_realtime_session_for_new_speech(
    http: Client,
    config: RealtimeAsrConfig,
    call_id: &str,
    trace_id: &str,
    vad: &SimpleVad,
    read_attributes: impl FnOnce() -> std::collections::HashMap<String, String>,
    upload_slot: &mut Option<RealtimeAsrUpload>,
    last_fixture_sequence: &mut Option<String>,
    realtime_enabled: bool,
) {
    let turn_id = format!("turn-{:04}", vad.turn_index);
    let metadata = match AudioIngressMetadata::from_participant(&read_attributes()) {
        Ok(metadata) => metadata,
        Err(reason) => {
            warn!(call_id = %call_id, trace_id = %trace_id, turn_id = %turn_id,
                reason, "runtime helper asr_realtime_metadata_rejected");
            return;
        }
    };
    if let Some(metadata) = metadata.as_ref() {
        if !fixture_sequence_is_new(
            last_fixture_sequence.as_deref(),
            &metadata.client_fixture_sequence,
        ) {
            warn!(call_id = %call_id, trace_id = %trace_id, turn_id = %turn_id,
                "runtime helper asr_realtime_metadata_sequence_rejected");
            return;
        }
    }
    match RealtimeAsrUpload::start(
        http,
        config,
        call_id,
        trace_id,
        &turn_id,
        &vad.speech_samples,
        metadata.as_ref(),
    ) {
        Ok(upload) => {
            if let Some(metadata) = metadata {
                *last_fixture_sequence = Some(metadata.client_fixture_sequence);
            }
            info!(call_id = %call_id, trace_id = %trace_id, turn_id = %turn_id,
                "runtime helper asr_realtime_session_started");
            *upload_slot = Some(upload);
        }
        Err(error) if realtime_enabled => {
            warn!(call_id = %call_id, trace_id = %trace_id, turn_id = %turn_id,
                error = %safe_error(&error.to_string()),
                "runtime helper asr_realtime_start_failed_fallback");
        }
        Err(_) => {}
    }
}

fn fixture_sequence_is_new(previous: Option<&str>, current: &str) -> bool {
    let Some(previous) = previous else {
        return true;
    };
    let current_number = current
        .rsplit_once('-')
        .and_then(|(_, value)| value.parse::<u64>().ok());
    let previous_number = previous
        .rsplit_once('-')
        .and_then(|(_, value)| value.parse::<u64>().ok());
    match (previous_number, current_number) {
        (Some(previous), Some(current)) => current > previous,
        _ => previous != current,
    }
}

struct DrainedUserAudioFrame {
@@ -3959,7 +4092,369 @@
        RuntimeTurnStreamState, RuntimeTurnStreamTimingPhase, runtime_session_nonce_hash,
        should_publish_device_output,
    };
    use std::collections::HashSet;
    use std::{
        collections::HashSet,
        io::{Read, Write},
        net::TcpListener,
        sync::{
            Arc,
            atomic::{AtomicUsize, Ordering},
            mpsc,
        },
        thread,
        time::Duration,
    };

    #[test]
    fn production_vad_session_boundary_reads_updated_attributes() {
        let config = SimpleVadConfig {
            rms_threshold: 0.001,
            peak_threshold: 0.01,
            start_frames: 2,
            end_silence_ms: 100,
            min_speech_ms: 1,
            max_turn_ms: 1_000,
            initial_ignore_ms: 0,
        };
        let mut vad = SimpleVad::new(config);
        let samples = vec![1_000i16; 160];
        let frame = AudioFrame {
            data: samples.as_slice().into(),
            sample_rate: 16_000,
            num_channels: 1,
            samples_per_channel: 160,
        };
        let mut attributes = std::collections::HashMap::from([
            (
                "inputSourceCategory".to_string(),
                "controlled_fixture".to_string(),
            ),
            (
                "clientFixtureSequence".to_string(),
                "fixture-01".to_string(),
            ),
        ]);
        let mut starts = Vec::new();
        for (session_index, sequence) in [(1, "fixture-01"), (2, "fixture-02")] {
            let was_in_speech = vad.in_speech;
            vad.observe_frame(
                "call-001",
                "trace-001",
                "participant",
                "track",
                session_index * 2 - 1,
                1_000 * session_index,
                &frame,
            );
            vad.observe_frame(
                "call-001",
                "trace-001",
                "participant",
                "track",
                session_index * 2,
                1_000 * session_index + 10,
                &frame,
            );
            let is_in_speech = vad.in_speech;
            assert!(!was_in_speech && is_in_speech);
            attributes.insert("clientFixtureSequence".to_string(), sequence.to_string());
            let metadata = AudioIngressMetadata::from_participant(&attributes)
                .expect("valid participant attributes")
                .expect("controlled fixture metadata");
            let session_line = asr_realtime::session_start_line(
                "call-001",
                "trace-001",
                &format!("turn-{session_index:04}"),
                "nonce-001",
                Some(&metadata),
            )
            .expect("session start line");
            let session_json: serde_json::Value =
                serde_json::from_slice(&session_line).expect("session start json");
            assert_eq!(sequence, session_json["clientFixtureSequence"]);
            starts.push(metadata.client_fixture_sequence);
            vad.reset_current_turn();
        }
        assert_eq!(vec!["fixture-01", "fixture-02"], starts);
        attributes.insert("inputSourceCategory".to_string(), "other".to_string());
        assert!(AudioIngressMetadata::from_participant(&attributes).is_err());
        assert!(
            AudioIngressMetadata::from_participant(&std::collections::HashMap::new())
                .expect("missing attributes is absent")
                .is_none()
        );
        attributes.insert(
            "clientFixtureSequence".to_string(),
            "fixture-01".to_string(),
        );
        assert!(AudioIngressMetadata::from_participant(&attributes).is_err());
    }

    #[test]
    fn production_observer_rejects_wrong_participant_before_vad_session() {
        assert!(!is_bound_user_participant(
            "participant-other",
            Some("participant-user")
        ));
        assert!(is_bound_user_participant(
            "participant-user",
            Some("participant-user")
        ));
        assert!(is_bound_user_participant("participant-any", None));
    }

    #[tokio::test]
    async fn production_observer_vad_to_session_entry_reads_each_updated_attribute() {
        let listener = TcpListener::bind("127.0.0.1:0").expect("bind local ASR fixture");
        let address = listener.local_addr().expect("fixture address");
        let (request_tx, request_rx) = mpsc::channel::<String>();
        let captured_count = Arc::new(AtomicUsize::new(0));
        let captured_count_for_server = Arc::clone(&captured_count);
        let server = thread::spawn(move || {
            for _ in 0..2 {
                let (mut stream, _) = listener.accept().expect("accept ASR session");
                stream
                    .set_read_timeout(Some(Duration::from_secs(2)))
                    .expect("set fixture timeout");
                let mut bytes = Vec::new();
                let mut buffer = [0_u8; 4096];
                loop {
                    match stream.read(&mut buffer) {
                        Ok(0) => break,
                        Ok(size) => {
                            bytes.extend_from_slice(&buffer[..size]);
                            if bytes.windows(7).any(|window| window == b"0\r\n\r\n") {
                                break;
                            }
                        }
                        Err(_) => break,
                    }
                }
                request_tx
                    .send(String::from_utf8_lossy(&bytes).into_owned())
                    .expect("capture ASR request");
                captured_count_for_server.fetch_add(1, Ordering::SeqCst);
                stream
                    .write_all(b"HTTP/1.1 200 OK\r\ncontent-type: application/json\r\ncontent-length: 39\r\nconnection: close\r\n\r\n{\"code\":0,\"data\":{\"status\":\"ok\"}}")
                    .expect("write fixture response");
            }
        });
        let mut vad = SimpleVad::new(SimpleVadConfig {
            rms_threshold: 0.001,
            peak_threshold: 0.01,
            start_frames: 1,
            end_silence_ms: 100,
            min_speech_ms: 1,
            max_turn_ms: 1_000,
            initial_ignore_ms: 0,
        });
        let frame_data = vec![1_000i16; 160];
        let frame = AudioFrame {
            data: frame_data.as_slice().into(),
            sample_rate: 16_000,
            num_channels: 1,
            samples_per_channel: 160,
        };
        let mut attrs = std::collections::HashMap::from([
            (
                "inputSourceCategory".to_string(),
                "controlled_fixture".to_string(),
            ),
            (
                "clientFixtureSequence".to_string(),
                "fixture-01".to_string(),
            ),
        ]);
        let mut upload = None;
        let mut last_fixture_sequence = None;
        let config = RealtimeAsrConfig {
            enabled: true,
            url: Some(format!("http://{address}/runtime/asr/realtime")),
            runtime_token: Some("test".to_string()),
            runtime_session_nonce: Some("test".to_string()),
            chunk_duration_ms: 200,
        };
        let (was, is, turn) = observe_bound_participant_frame(
            "participant-user",
            Some("participant-user"),
            &mut vad,
            "call-001",
            "trace-001",
            "participant-user",
            "track-001",
            1,
            1_000,
            &frame,
            Client::new(),
            config.clone(),
            || attrs.clone(),
            &mut upload,
            &mut last_fixture_sequence,
            true,
        );
        assert!(!was && is && turn.is_none());
        assert!(upload.is_some());
        upload.take().unwrap().cancel("test").await;
        vad.reset_current_turn();
        attrs.insert(
            "clientFixtureSequence".to_string(),
            "fixture-02".to_string(),
        );
        let (was, is, turn) = observe_bound_participant_frame(
            "participant-user",
            Some("participant-user"),
            &mut vad,
            "call-001",
            "trace-001",
            "participant-user",
            "track-001",
            2,
            2_000,
            &frame,
            Client::new(),
            config,
            || attrs.clone(),
            &mut upload,
            &mut last_fixture_sequence,
            true,
        );
        assert!(!was && is && turn.is_none());
        assert!(upload.is_some());
        upload.take().unwrap().cancel("test").await;

        let first_request = request_rx
            .recv_timeout(Duration::from_secs(2))
            .expect("first session request");
        let second_request = request_rx
            .recv_timeout(Duration::from_secs(2))
            .expect("second session request");
        assert!(first_request.contains("\\\"clientFixtureSequence\\\":\\\"fixture-01\\\""));
        assert!(second_request.contains("\\\"clientFixtureSequence\\\":\\\"fixture-02\\\""));
        // The same production boundary rejects a wrong participant before VAD/session creation.
        assert!(!is_bound_user_participant(
            "participant-other",
            Some("participant-user")
        ));
        assert_eq!(0, request_rx.try_iter().count());
        vad.reset_current_turn();
        attrs.insert(
            "clientFixtureSequence".to_string(),
            "fixture-03".to_string(),
        );
        let (_, is_wrong, wrong_turn) = observe_bound_participant_frame(
            "participant-other",
            Some("participant-user"),
            &mut vad,
            "call-001",
            "trace-001",
            "participant-user",
            "track-001",
            3,
            3_000,
            &frame,
            Client::new(),
            RealtimeAsrConfig {
                enabled: true,
                url: Some(format!("http://{address}/runtime/asr/realtime")),
                runtime_token: Some("test".to_string()),
                runtime_session_nonce: Some("test".to_string()),
                chunk_duration_ms: 200,
            },
            || attrs.clone(),
            &mut upload,
            &mut last_fixture_sequence,
            true,
        );
        assert!(!is_wrong && wrong_turn.is_none() && upload.is_none());
        vad.reset_current_turn();
        attrs.insert(
            "clientFixtureSequence".to_string(),
            "fixture-01".to_string(),
        );
        let (_, _, _) = observe_bound_participant_frame(
            "participant-user",
            Some("participant-user"),
            &mut vad,
            "call-001",
            "trace-001",
            "participant-user",
            "track-001",
            4,
            4_000,
            &frame,
            Client::new(),
            RealtimeAsrConfig {
                enabled: true,
                url: Some(format!("http://{address}/runtime/asr/realtime")),
                runtime_token: Some("test".to_string()),
                runtime_session_nonce: Some("test".to_string()),
                chunk_duration_ms: 200,
            },
            || attrs.clone(),
            &mut upload,
            &mut last_fixture_sequence,
            true,
        );
        assert!(upload.is_none());
        vad.reset_current_turn();
        let (_, _, _) = observe_bound_participant_frame(
            "participant-user",
            Some("participant-user"),
            &mut vad,
            "call-001",
            "trace-001",
            "participant-user",
            "track-001",
            5,
            5_000,
            &frame,
            Client::new(),
            RealtimeAsrConfig {
                enabled: true,
                url: Some(format!("http://{address}/runtime/asr/realtime")),
                runtime_token: Some("test".to_string()),
                runtime_session_nonce: Some("test".to_string()),
                chunk_duration_ms: 200,
            },
            || attrs.clone(),
            &mut upload,
            &mut last_fixture_sequence,
            true,
        );
        assert!(upload.is_none());
        vad.reset_current_turn();
        attrs.insert("inputSourceCategory".to_string(), "other".to_string());
        let mut invalid_upload = None;
        let (_, _, invalid_turn) = observe_bound_participant_frame(
            "participant-user",
            Some("participant-user"),
            &mut vad,
            "call-001",
            "trace-001",
            "participant-other",
            "track-001",
            3,
            3_000,
            &frame,
            Client::new(),
            RealtimeAsrConfig {
                enabled: true,
                url: Some("http://127.0.0.1:9".to_string()),
                runtime_token: Some("test".to_string()),
                runtime_session_nonce: Some("test".to_string()),
                chunk_duration_ms: 200,
            },
            || attrs,
            &mut invalid_upload,
            &mut last_fixture_sequence,
            true,
        );
        assert!(invalid_turn.is_none());
        assert!(invalid_upload.is_none());
        assert_eq!(2, captured_count.load(Ordering::SeqCst));
        assert_eq!(0, request_rx.try_iter().count());
        server.join().expect("fixture server");
    }

    #[test]
    fn reply_chunk_marker_state_emits_turn_first_once_and_later_segment_first_once() {