fix: Don't reuse session in NVIDIA post_training request handler

llama_stack/providers/remote/post_training/nvidia/post_training.py

@@ -67,18 +67,12 @@ class NvidiaPostTrainingAdapter(ModelRegistryHelper):
         self.timeout = aiohttp.ClientTimeout(total=config.timeout)
         # TODO: filter by available models based on /config endpoint
         ModelRegistryHelper.__init__(self, model_entries=_MODEL_ENTRIES)
-        self.session = None
 
         self.customizer_url = config.customizer_url
         if not self.customizer_url:
             warnings.warn("Customizer URL is not set, using default value: http://nemo.test", stacklevel=2)
             self.customizer_url = "http://nemo.test"
 
-    async def _get_session(self) -> aiohttp.ClientSession:
-        if self.session is None or self.session.closed:
-            self.session = aiohttp.ClientSession(headers=self.headers, timeout=self.timeout)
-        return self.session
-
     async def _make_request(
         self,
         method: str,
@@ -99,13 +93,13 @@ class NvidiaPostTrainingAdapter(ModelRegistryHelper):
         if json and "Content-Type" not in request_headers:
             request_headers["Content-Type"] = "application/json"
 
-        session = await self._get_session()
         for _ in range(self.config.max_retries):
-            async with session.request(method, url, params=params, json=json, **kwargs) as response:
-                if response.status >= 400:
-                    error_data = await response.json()
-                    raise Exception(f"API request failed: {error_data}")
-                return await response.json()
+            async with aiohttp.ClientSession(headers=request_headers) as session:
+                async with session.request(method, url, params=params, json=json, **kwargs) as response:
+                    if response.status >= 400:
+                        error_data = await response.json()
+                        raise Exception(f"API request failed: {error_data}")
+                    return await response.json()
 
     async def get_training_jobs(
         self,
@@ -176,6 +170,7 @@ class NvidiaPostTrainingAdapter(ModelRegistryHelper):
             - metrics: Optional[Dict] - Additional training metrics
             - status_logs: Optional[List] - Detailed logs of status changes
         """
+        print("Using local Llama Stack Customizer API")
         response = await self._make_request(
             "GET",
             f"/v1/customization/jobs/{job_uuid}/status",