From 3738bf4fda421d85e3ba7e7be4505f5076698501 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Onur=20=C3=96zkan?= <work@onurozkan.dev>
Date: Sun, 19 Jul 2026 23:20:34 +0300
Subject: [PATCH] libs/kaptan-runtime:telemetry: use best-effort approach
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Signed-off-by: Onur Özkan <work@onurozkan.dev>
---
 libs/kaptan-runtime/src/telemetry.rs | 30 +++++++++++-----------------
 1 file changed, 12 insertions(+), 18 deletions(-)

diff --git a/libs/kaptan-runtime/src/telemetry.rs b/libs/kaptan-runtime/src/telemetry.rs
index d5021a8..d049cfe 100644
--- a/libs/kaptan-runtime/src/telemetry.rs
+++ b/libs/kaptan-runtime/src/telemetry.rs
@@ -5,15 +5,13 @@ use kaptan_mavlink::{MavlinkFrame, MavlinkSender, message::MavState};
 use kaptan_sensor::ImuSnapshot;
 use kaptan_tx::{FrameClass, PendingFrame, TransmitQueue};
 
-/// Terminal fault from the telemetry worker.
+/// Failure while preparing or starting one telemetry frame.
 #[derive(Debug)]
 pub enum TelemetryFault<MemoryError, EngineError> {
     /// DMA-visible frame preparation failed.
     Memory(MemoryError),
-    /// The UART DMA route rejected or faulted a transfer.
+    /// The UART DMA route rejected a transfer start.
     Engine(EngineError),
-    /// The DMA route cannot continue without explicit board recovery.
-    RouteHalted,
 }
 
 /// Owns MAVLink packet sequencing and UART DMA frame lifecycle.
@@ -61,20 +59,19 @@ where
         self.enqueue_and_start(FrameClass::Critical, frame)
     }
 
-    /// Releases a completed DMA frame and starts at most one next frame.
-    pub fn on_dma_complete(
-        &mut self,
-        completion: TxCompletion,
-    ) -> Result<(), TelemetryFault<Memory::Error, Engine::StartError>> {
+    /// Releases a terminal DMA frame and opportunistically starts the next.
+    ///
+    /// Telemetry is best-effort: a terminal route fault drops only the active
+    /// frame and a rejected follow-up start is retried on later publication.
+    pub fn on_dma_complete(&mut self, completion: TxCompletion) {
         match completion {
-            TxCompletion::NotPending => Ok(()),
+            TxCompletion::NotPending => {}
             TxCompletion::Complete => {
                 let _ = self.transmit.complete();
-                self.start_next()
+                let _ = self.start_next();
             }
             TxCompletion::TransferFault | TxCompletion::Halted => {
                 let _ = self.transmit.fail();
-                Err(TelemetryFault::RouteHalted)
             }
         }
     }
@@ -103,7 +100,7 @@ where
 
 #[cfg(test)]
 mod tests {
-    use super::{TelemetryFault, TelemetryService};
+    use super::TelemetryService;
     use kaptan_dma::{DmaReadableBuffer, DmaTxBufferFactory, DmaTxEngine, TxCompletion};
     use kaptan_sensor::ImuSnapshot;
     use kaptan_time::Timestamp;
@@ -134,16 +131,13 @@ mod tests {
     }
 
     #[test]
-    fn transfer_fault_halts_without_starting_the_next_frame() {
+    fn transfer_fault_drops_only_the_active_frame() {
         let mut service = TelemetryService::<Memory, Engine, 2>::new(1, 1, Memory, Engine);
         service.publish_sample(&sample(1)).unwrap();
         service.publish_sample(&sample(2)).unwrap();
         assert!(service.transmit.is_active());
 
-        assert!(matches!(
-            service.on_dma_complete(TxCompletion::TransferFault),
-            Err(TelemetryFault::RouteHalted)
-        ));
+        service.on_dma_complete(TxCompletion::TransferFault);
         assert!(!service.transmit.is_active());
     }
 }