feat(irtt): make IRTT measurement optional and refine engine behavior

Conditionally compile IRTT functionality behind the `irtt` feature flag to allow building smaller binaries without IRTT dependencies. Enhance IRTT engine shutdown, configuration, and clarify ICMP protocol names.

src/controller.rs

@@ -8,10 +8,11 @@ use std::{
 use flume::{Receiver, SendError, Sender};
 use thiserror::Error;
 
+#[cfg(feature = "irtt")]
+use crate::measurement::irtt::IrttBinding;
 use crate::{
     measurement::{
         icmp::IcmpBinding,
-        irtt::IrttBinding,
         model::{MeasurementSource, MeasurementStream, MeasurementStreamId, ProbeSchedule},
     },
     settings::ReflectorDefinition,
@@ -21,6 +22,7 @@ use crate::{
 pub enum ControllerError {
     #[error("ICMP channel error")]
     IcmpChannelError(#[from] SendError<Vec<IcmpBinding>>),
+    #[cfg(feature = "irtt")]
     #[error("IRTT channel error")]
     IrttChannelError(#[from] SendError<Vec<IrttBinding>>),
 }
@@ -28,6 +30,7 @@ pub enum ControllerError {
 pub struct Controller {
     reflector_rx: Receiver<Vec<SocketAddr>>,
     icmp_binding_tx: Sender<Vec<IcmpBinding>>,
+    #[cfg(feature = "irtt")]
     irtt_binding_tx: Sender<Vec<IrttBinding>>,
     reflectors: HashMap<SocketAddr, ReflectorDefinition>,
     active_streams: Arc<RwLock<Vec<MeasurementStream>>>,
@@ -42,7 +45,7 @@ impl Controller {
     pub fn new(
         reflector_rx: Receiver<Vec<SocketAddr>>,
         icmp_binding_tx: Sender<Vec<IcmpBinding>>,
-        irtt_binding_tx: Sender<Vec<IrttBinding>>,
+        #[cfg(feature = "irtt")] irtt_binding_tx: Sender<Vec<IrttBinding>>,
         reflectors: HashMap<SocketAddr, ReflectorDefinition>,
         active_streams: Arc<RwLock<Vec<MeasurementStream>>>,
         endpoint_streams: Arc<RwLock<HashMap<SocketAddr, MeasurementStream>>>,
@@ -51,6 +54,7 @@ impl Controller {
         Self {
             reflector_rx,
             icmp_binding_tx,
+            #[cfg(feature = "irtt")]
             irtt_binding_tx,
             reflectors,
             active_streams,
@@ -90,18 +94,21 @@ impl Controller {
     ) -> Result<(), ControllerError> {
         let count = endpoints.len();
         let mut icmp = Vec::new();
+        #[cfg(feature = "irtt")]
         let mut irtt = Vec::new();
         let mut streams = Vec::with_capacity(count);
         let mut endpoint_streams = HashMap::new();
         for (index, endpoint) in endpoints.into_iter().enumerate() {
-            let Some((port, hmac)) = self.reflectors.get(&endpoint).map(|definition| {
-                (
-                    definition.irtt_port.unwrap_or(2112),
-                    definition.irtt_hmac.clone(),
-                )
-            }) else {
+            let Some(_definition) = self.reflectors.get(&endpoint) else {
                 continue;
             };
+            #[cfg(feature = "irtt")]
+            let (port, hmac) = {
+                (
+                    _definition.irtt_port.unwrap_or(2112),
+                    _definition.irtt_hmac.clone(),
+                )
+            };
             let stream = self.stream_for(endpoint);
             let schedule = ProbeSchedule {
                 period: self.period,
@@ -111,9 +118,12 @@ impl Controller {
                 MeasurementSource::IcmpEcho | MeasurementSource::IcmpTimestamp => {
                     icmp.push(IcmpBinding::new(stream, schedule))
                 }
+                #[cfg(feature = "irtt")]
                 MeasurementSource::Irtt => {
                     irtt.push(IrttBinding::new(stream, schedule, port, hmac))
                 }
+                #[cfg(not(feature = "irtt"))]
+                MeasurementSource::Irtt => unreachable!("IRTT feature is checked before startup"),
                 _ => unreachable!("unsupported reflector measurement source"),
             }
             streams.push(stream);
@@ -128,6 +138,7 @@ impl Controller {
             .write()
             .expect("endpoint stream lock poisoned") = endpoint_streams;
         self.icmp_binding_tx.send_async(icmp).await?;
+        #[cfg(feature = "irtt")]
         self.irtt_binding_tx.send_async(irtt).await?;
         Ok(())
     }

src/main.rs

@@ -22,6 +22,7 @@ mod util;
 use crate::baseliner::Baseliner;
 use crate::controller::Controller;
 use crate::measurement::icmp::IcmpEngine;
+#[cfg(feature = "irtt")]
 use crate::measurement::irtt::IrttEngine;
 use crate::measurement::model::{MeasurementSource, MeasurementStream};
 use crate::metrics::{Metric, Metrics, MetricsSender};
@@ -279,6 +280,12 @@ fn wait_for_exit(error_rx: &flume::Receiver<anyhow::Error>) -> anyhow::Result<()
 }
 
 fn run(settings: &Settings) -> anyhow::Result<()> {
+    #[cfg(not(feature = "irtt"))]
+    if settings.advanced_settings.measurement_type == ReflectorProtocol::Irtt {
+        anyhow::bail!(
+            "IRTT measurement selected, but this binary was built without the `irtt` feature"
+        );
+    }
     let rt = tokio::runtime::Runtime::new()?;
 
     if settings.advanced_settings.dry_run {
@@ -299,6 +306,7 @@ fn run(settings: &Settings) -> anyhow::Result<()> {
     let (control_snapshot_tx, control_snapshot_rx) = flume::unbounded();
     let (error_tx, error_rx) = flume::unbounded::<anyhow::Error>();
     let (icmp_binding_tx, icmp_binding_rx) = flume::unbounded();
+    #[cfg(feature = "irtt")]
     let (irtt_binding_tx, irtt_binding_rx) = flume::unbounded();
     let (measurement_tx, measurement_rx) = flume::unbounded();
     let (reflector_tx, reflector_rx) = flume::unbounded();
@@ -318,6 +326,7 @@ fn run(settings: &Settings) -> anyhow::Result<()> {
     let controller = Controller::new(
         reflector_rx,
         icmp_binding_tx,
+        #[cfg(feature = "irtt")]
         irtt_binding_tx,
         reflectors,
         Arc::clone(&active_streams),
@@ -333,13 +342,20 @@ fn run(settings: &Settings) -> anyhow::Result<()> {
             icmp_binding_rx,
         )?
     };
-    let (_irtt_task, irtt_engine) = {
+    #[cfg(feature = "irtt")]
+    let (irtt_task, irtt_engine) = {
         let _guard = rt.enter();
-        IrttEngine::new(start_time, measurement_tx, irtt_binding_rx)?
+        IrttEngine::new(
+            start_time,
+            Duration::from_secs_f64(settings.advanced_settings.tick_interval),
+            measurement_tx,
+            irtt_binding_rx,
+        )?
     };
 
     spawn_task(&rt, &error_tx, icmp_engine.run());
-    spawn_task(&rt, &error_tx, irtt_engine.run());
+    #[cfg(feature = "irtt")]
+    spawn_task(&rt, &error_tx, irtt_engine.run(irtt_task));
 
     let dropped = Arc::new(AtomicU32::new(0));
 

src/measurement/irtt.rs

@@ -2,7 +2,7 @@ use std::{collections::HashMap, net::SocketAddr, time::Instant};
 
 use flume::{Receiver, Sender};
 use irtt_client::{
-    ClientConfig, ClientEvent,
+    ClientConfig, ClientEvent, NegotiationPolicy, OpenPolicy,
     managed::{
         ManagedClient, ManagedClientConfig, ManagedClientHandle, ManagedClientTask,
         ManagedCommandAcknowledgement, ManagedCommandApplyError, ManagedCommandError,
@@ -15,6 +15,7 @@ use log::{debug, trace, warn};
 use thiserror::Error;
 use tokio::sync::broadcast::error::RecvError;
 
+use crate::SHUTDOWN;
 use crate::measurement::model::{
     MeasurementEvent, MeasurementLoss, MeasurementObservation, MeasurementStream,
     MeasurementStreamId, OneWayClock, OneWayLatency, ProbeSchedule, SignedDuration,
@@ -52,6 +53,9 @@ pub enum IrttError {
 
 pub struct IrttBinding {
     stream: MeasurementStream,
+    /// Retained for future hybrid-mode scheduling. IRTT currently uses the
+    /// global interval configured on its managed client.
+    #[allow(dead_code)]
     schedule: ProbeSchedule,
     port: u16,
     hmac: Option<String>,
@@ -87,20 +91,11 @@ pub struct IrttEngine {
 impl IrttEngine {
     pub fn new(
         origin: Instant,
+        interval: std::time::Duration,
         observation_tx: Sender<MeasurementEvent>,
         binding_rx: Receiver<Vec<IrttBinding>>,
     ) -> Result<(ManagedClientTask, Self), IrttError> {
-        let config = ManagedClientConfig {
-            client: ClientConfig {
-                request: irtt_client::SessionRequest {
-                    duration: None,
-                    ..Default::default()
-                },
-                ..Default::default()
-            },
-            completion: ManagedCompletionPolicy::ExplicitStop,
-            ..Default::default()
-        };
+        let config = managed_client_config(interval);
         let (task, handle) = ManagedClient::task(config, Vec::new())?;
 
         Ok((
@@ -142,11 +137,19 @@ impl IrttEngine {
         Ok(())
     }
 
-    pub async fn run(mut self) -> Result<(), IrttError> {
+    pub async fn run(mut self, task: ManagedClientTask) -> Result<(), IrttError> {
+        let mut task = Box::pin(task);
         let mut events = self.client.subscribe()?;
 
         loop {
             tokio::select! {
+                outcome = task.as_mut() => {
+                    return match outcome.end_reason {
+                        ManagedEndReason::StopRequested => Ok(()),
+                        end_reason => Err(IrttError::ManagedFailure(end_reason)),
+                    };
+                }
+
                 bindings = self.binding_rx.recv_async() => {
                     let bindings = bindings
                         .map_err(|_| IrttError::BindingChannelClosed)?;
@@ -338,11 +341,51 @@ impl IrttEngine {
                         }
                     }
                 }
+
+                _ = tokio::time::sleep(std::time::Duration::from_millis(100)) => {
+                    if SHUTDOWN.load(std::sync::atomic::Ordering::Relaxed) {
+                        let stop = self.client.stop();
+                        tokio::pin!(stop);
+                        tokio::select! {
+                            _ = &mut stop => {},
+                            outcome = task.as_mut() => {
+                                return match outcome.end_reason {
+                                    ManagedEndReason::StopRequested => Ok(()),
+                                    end_reason => Err(IrttError::ManagedFailure(end_reason)),
+                                };
+                            }
+                        }
+                        let outcome = task.await;
+                        return match outcome.end_reason {
+                            ManagedEndReason::StopRequested => Ok(()),
+                            end_reason => Err(IrttError::ManagedFailure(end_reason)),
+                        };
+                    }
+                }
             }
         }
     }
 }
 
+fn managed_client_config(interval: std::time::Duration) -> ManagedClientConfig {
+    ManagedClientConfig {
+        client: ClientConfig {
+            request: irtt_client::SessionRequest {
+                duration: None,
+                interval,
+                ..Default::default()
+            },
+            open: OpenPolicy {
+                negotiation: NegotiationPolicy::Strict,
+                ..Default::default()
+            },
+            ..Default::default()
+        },
+        completion: ManagedCompletionPolicy::ExplicitStop,
+        ..Default::default()
+    }
+}
+
 fn map_one_way(sample: irtt_client::OneWayDelaySample) -> Option<OneWayLatency> {
     let uplink = i64::try_from(sample.client_to_server?.as_nanos()).ok()?;
 

src/measurement/model.rs

@@ -20,7 +20,7 @@ pub enum MeasurementSource {
 impl Display for MeasurementSource {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
-            MeasurementSource::IcmpEcho => write!(f, "icmp"),
+            MeasurementSource::IcmpEcho => write!(f, "icmp-echo"),
             MeasurementSource::IcmpTimestamp => write!(f, "icmp-timestamps"),
             MeasurementSource::Irtt => write!(f, "irtt"),
             MeasurementSource::TcpSeqAck => write!(f, "tcp-seqack"),

src/settings/mod.rs

@@ -89,7 +89,7 @@ pub enum ReflectorProtocol {
 impl Display for ReflectorProtocol {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
-            ReflectorProtocol::IcmpEcho => write!(f, "icmp"),
+            ReflectorProtocol::IcmpEcho => write!(f, "icmp-echo"),
             ReflectorProtocol::IcmpTimestamps => write!(f, "icmp-timestamps"),
             ReflectorProtocol::Irtt => write!(f, "irtt"),
         }
@@ -101,8 +101,8 @@ impl FromStr for ReflectorProtocol {
 
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         match s.to_lowercase().as_str() {
-            "icmp" => Ok(ReflectorProtocol::IcmpEcho),
-            "icmp-timestamps" | "icmp_timestamps" => Ok(ReflectorProtocol::IcmpTimestamps),
+            "icmp-echo" => Ok(ReflectorProtocol::IcmpEcho),
+            "icmp-timestamps" => Ok(ReflectorProtocol::IcmpTimestamps),
             "irtt" => Ok(ReflectorProtocol::Irtt),
             _ => Err(ConfigError::Message(format!(
                 "invalid measurement type: {s}"
@@ -137,15 +137,15 @@ pub(crate) struct ReflectorDefinition {
     pub(crate) country: Option<String>,
     pub(crate) protocols: Vec<ReflectorProtocol>,
     pub(crate) irtt_port: Option<u16>,
+    #[allow(dead_code)]
     pub(crate) irtt_hmac: Option<String>,
 }
 
 #[derive(Debug, Deserialize)]
 struct ReflectorRow {
-    #[serde(alias = "reflector_ip")]
     host: String,
     country: Option<String>,
-    protocols: Option<String>,
+    protocols: String,
     irtt_port: Option<u16>,
     irtt_hmac: Option<String>,
 }
@@ -246,18 +246,18 @@ impl ReflectorSettings {
                 .map_err(|error| ConfigError::Message(error.to_string()))?;
             for row in reader.deserialize::<ReflectorRow>() {
                 let row = row.map_err(|error| ConfigError::Message(error.to_string()))?;
-                let protocols = match row.protocols {
-                    Some(protocols) => protocols
-                        .split(['|', ';'])
-                        .map(str::trim)
-                        .filter(|protocol| !protocol.is_empty())
-                        .map(ReflectorProtocol::from_str)
-                        .collect::<Result<Vec<_>, _>>()?,
-                    None => vec![
-                        ReflectorProtocol::IcmpEcho,
-                        ReflectorProtocol::IcmpTimestamps,
-                    ],
-                };
+                let protocols = row
+                    .protocols
+                    .split(['|', ';'])
+                    .map(str::trim)
+                    .filter(|protocol| !protocol.is_empty())
+                    .map(ReflectorProtocol::from_str)
+                    .collect::<Result<Vec<_>, _>>()?;
+                if protocols.is_empty() {
+                    return Err(ConfigError::Message(format!(
+                        "reflector row in {path} has no protocols"
+                    )));
+                }
                 self.entries.push(ReflectorDefinition {
                     host: row.host,
                     country: row.country,