fix: handle ContentTypeError in dynamic client discovery (#368)

* fix: handle ContentTypeError in dynamic client discovery

When the Kubernetes API server returns a 503 Service Unavailable with text/plain
content type instead of JSON, the dynamic client was failing with a ContentTypeError
while trying to parse the response. This fix catches ContentTypeError in the
get_resources_for_api_version method and handles it the same way as ServiceUnavailableError,
allowing the client to gracefully continue with an empty resources list.

This resolves issues when accessing certain API endpoints that may temporarily
return non-JSON responses during service unavailability

* #368 - handle ContentTypeError in dynamic client discovery

Fix import sorting

* #368 - handle ContentTypeError in dynamic client discovery 

Fix import sorting

Author: tamilhce

kubernetes_asyncio/dynamic/discovery.py

@@ -22,6 +22,7 @@
 from functools import partial
 from typing import Dict
 
+from aiohttp.client_exceptions import ContentTypeError
 from urllib3.exceptions import MaxRetryError, ProtocolError
 
 from kubernetes_asyncio import __version__
@@ -183,7 +184,9 @@ async def get_resources_for_api_version(self, prefix, group, version, preferred)
         try:
             response = await self.client.request('GET', path)
             resources_response = response.resources or []
-        except ServiceUnavailableError:
+        except (ServiceUnavailableError, ContentTypeError):
+            # Handle both service unavailable errors and content type errors
+            # (e.g., when server returns 503 with text/plain)
             resources_response = []
 
         resources_raw = list(filter(lambda r: '/' not in r['name'], resources_response))