Fix native health polling and isolate file operation traffic

agent/tests/test_update_integration.py

@@ -118,6 +118,44 @@ class UpdateIntegrationTests(unittest.TestCase):
             self.agent.read_loop()
             dispatch.assert_not_called()
 
+    def test_health_lane_runs_while_file_receipt_for_same_instance_is_slow(self):
+        receipt_waiting, release_receipt, health_done = threading.Event(), threading.Event(), threading.Event()
+        file_op = {"id": "file-one", "kind": "files.read", "instanceId": "same", "payload": {}}
+        health_op = {"id": "health-one", "kind": "instance.inspect", "instanceId": "same", "payload": {}}
+        errors = []
+        def request(method, path, body=None):
+            if method == "GET":
+                return {"operations": [health_op if "lane=health" in path else file_op]}
+            if path.endswith("file-one") and body["state"] == "completed":
+                receipt_waiting.set()
+                release_receipt.wait(3)
+            return {}
+        def dispatch(operation):
+            if operation["id"] == "health-one":
+                health_done.set()
+                self.agent.stopping.set()
+            return {"ok": True}
+        def run(lane):
+            try: self.agent.read_loop(lane)
+            except Exception as error: errors.append(error)
+        self.agent.request, self.agent.dispatch = request, dispatch
+        files = threading.Thread(target=run, args=("read",))
+        health = threading.Thread(target=run, args=("health",))
+        files.start()
+        try:
+            self.assertTrue(receipt_waiting.wait(2))
+            health.start()
+            self.assertTrue(health_done.wait(2), "Health waited for a file receipt")
+        finally:
+            self.agent.stopping.set()
+            release_receipt.set()
+            files.join(3)
+            if health.ident is not None: health.join(3)
+        self.assertFalse(files.is_alive())
+        self.assertFalse(health.is_alive())
+        self.assertEqual(errors, [])
+        self.assertEqual(self.agent.journal.get("health-one")["state"], "completed")
+
     def test_instance_mutations_and_global_mutations_exclude_observations(self):
         operation = {"instanceId": "one"}
         entered = threading.Event()