kubernetes-client
Kubernetes Async API Calls with Callbacks Support
Kubernetes API calls do support async operations. As of now, we don't a have to provide the callbacks for async calls. It would be good idea to provide success and failure callbacks to avoid polling for the result.
Example: create_namespaced_pod(namespace, body, async_req=True, async_callback, async_error_callback)
Upstream Kubernetes API doesn't support such callback mechanism AFAICT. Could you check with the upstream on this feature request?
@roycaihw Async calls are submitted through python thread pool. Python thread pool does support callbacks.
Check api_client.py for the same
if not async_req:
return self.__call_api(resource_path, method,
path_params, query_params, header_params,
body, post_params, files,
response_type, auth_settings,
_return_http_data_only, collection_formats,
_preload_content, _request_timeout, _host)
return self.pool.apply_async(self.__call_api, (resource_path,
method, path_params,
query_params,
header_params, body,
post_params, files,
response_type,
auth_settings,
_return_http_data_only,
collection_formats,
_preload_content,
_request_timeout,
_host))
apply_async returns AsyncResult so as you've written it doesn't support callbacks. These functions are auto-generated by OpenAPI Generator so it's not easy to introduce such change.
I can suggest using sync api calls but from a dedicated thread pool where you can add callbacks as you need. What do you think?
@tomplus We were avoiding the synchronous requests due to performance reasons. It would be great if we make the requests asyncronous with callbacks support.
Correct me if I'm wrong but you want to have something like this:
create_namespaced_pod("pod-1", "ns-1", cb_success, cb_error)
create_namespaced_pod("pod-2", "ns-2", cb_success, cb_error)
so instead of using async_req i suggest you implement it in this way (draft):
def cb_helper(func_name, cb_success, cb_error, *args, **kwargs):
try:
result = func_name(*args, **kwargs)
except Exception as ex:
cb_error(ex)
cb_success(result)
pool = with ThreadPool()
pool.apply_async(cb_helper, create_namespaced_pod, "pod-1", "ns-1", cb_success, cb_error)
pool.apply_async(cb_helper, create_namespaced_pod, "pod-2", "ns-2", cb_success, cb_error)
....
....
so it uses synchronous requests but from threads so main thread is not blocked...
Marking this as resolved. Please let us know if you have more questions
/close
@roycaihw: Closing this issue.
In response to this:
Marking this as resolved. Please let us know if you have more questions
/close
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