fix(k1): stabilize repeated acquisition and live viewer recovery

tests/test_rerun_bridge.py

@@ -1,6 +1,8 @@
 from __future__ import annotations
 
 import json
+import logging
+import socket
 import struct
 import threading
 import time
@@ -20,6 +22,7 @@ from k1link.viewer.rerun_bridge import (
     RerunSceneSettings,
     _live_time_panel,
     _point_colors,
+    _select_available_grpc_port,
 )
 
 
@@ -62,6 +65,33 @@ class DisconnectFailureRecording(FakeRecording):
         raise RuntimeError("synthetic disconnect failure")
 
 
+def test_rerun_port_selection_skips_a_recording_still_held_by_a_viewer(
+    caplog: pytest.LogCaptureFixture,
+) -> None:
+    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as occupied:
+        occupied.bind(("0.0.0.0", 0))
+        occupied.listen()
+        preferred_port = int(occupied.getsockname()[1])
+
+        selected_port = _select_available_grpc_port(preferred_port, search_span=8)
+        recording = FakeRecording()
+        with caplog.at_level(
+            logging.INFO,
+            logger="k1link.device_plugins.xgrids_k1.viewer_receiver",
+        ):
+            bridge = RerunBridge(
+                grpc_port=preferred_port,
+                recording_factory=lambda _: recording,  # type: ignore[arg-type]
+            )
+
+    assert selected_port != preferred_port
+    assert preferred_port < selected_port < preferred_port + 8
+    assert caplog.records[-1].event_code == "rerun_grpc_port_rotated"
+    assert caplog.records[-1].preferred_port == preferred_port
+    assert caplog.records[-1].selected_port == selected_port
+    bridge.close()
+
+
 def _message(
     topic: str,
     payload: bytes,
@@ -266,7 +296,7 @@ def test_palettes_are_deterministic_and_custom_color_is_exact() -> None:
     assert custom_over_rgb.tolist() == [[16, 32, 48], [16, 32, 48]]
 
 
-def test_runtime_reuses_one_bridge_across_sequential_sessions(tmp_path: Path) -> None:
+def test_runtime_owns_fresh_bridge_for_each_sequential_session(tmp_path: Path) -> None:
     capture = tmp_path / "mqtt.raw.k1mqtt"
     point_topic = "RealtimePointcloud"
     pose_topic = "RealtimePath"
@@ -300,10 +330,12 @@ def test_runtime_reuses_one_bridge_across_sequential_sessions(tmp_path: Path) ->
         encoding="utf-8",
     )
 
-    recording = FakeRecording()
+    recordings: list[FakeRecording] = []
     created: list[RerunBridge] = []
 
     def bridge_factory(**kwargs: object) -> RerunBridge:
+        recording = FakeRecording()
+        recordings.append(recording)
         bridge = RerunBridge(
             recording_factory=lambda _: recording,  # type: ignore[arg-type]
             **kwargs,  # type: ignore[arg-type]
@@ -329,8 +361,8 @@ def test_runtime_reuses_one_bridge_across_sequential_sessions(tmp_path: Path) ->
     assert snapshot["metrics"]["mqtt_to_publish_ms"] is None
     runtime.stop(wait_seconds=5.0)
     assert runtime.snapshot()["phase"] == "idle"
-    assert runtime.snapshot()["rerun_grpc_url"] == "rerun+http://127.0.0.1:9876/proxy"
-    assert recording.disconnected is False
+    assert runtime.snapshot()["rerun_grpc_url"] is None
+    assert recordings[0].disconnected is True
 
     runtime.start_replay(capture, speed=0.0)
     deadline = time.monotonic() + 5.0
@@ -340,13 +372,12 @@ def test_runtime_reuses_one_bridge_across_sequential_sessions(tmp_path: Path) ->
         time.sleep(0.05)
     runtime.stop(wait_seconds=5.0)
 
-    assert len(created) == 1
+    assert len(created) == 2
     assert runtime.snapshot()["metrics"]["pcl_frames"] == 1
-    assert runtime.snapshot()["rerun_grpc_url"] == "rerun+http://127.0.0.1:9876/proxy"
-    assert recording.disconnected is False
+    assert runtime.snapshot()["rerun_grpc_url"] is None
+    assert all(recording.disconnected for recording in recordings)
     runtime.close()
     assert runtime.snapshot()["rerun_grpc_url"] is None
-    assert recording.disconnected is True
 
 
 def test_runtime_reports_bridge_close_failure_instead_of_false_idle(tmp_path: Path) -> None:
@@ -385,18 +416,11 @@ def test_runtime_reports_bridge_close_failure_instead_of_false_idle(tmp_path: Pa
         time.sleep(0.01)
         snapshot = runtime.snapshot()
 
-    assert snapshot["phase"] == "idle"
-    assert snapshot["rerun_grpc_url"] == "rerun+http://127.0.0.1:9876/proxy"
-    assert recording.disconnected is False
-
-    with pytest.raises(RuntimeError, match="synthetic disconnect failure"):
-        runtime.close()
-
-    snapshot = runtime.snapshot()
     assert snapshot["phase"] == "error"
     assert "synthetic disconnect failure" in snapshot["message"]
     assert snapshot["rerun_grpc_url"] is None
     assert recording.disconnected is True
+    runtime.close()
 
 
 def test_close_during_blocked_factory_closes_the_late_bridge(tmp_path: Path) -> None: