gistfile1.txt

def drain_node(*, node: kubernetes.client.models.V1Node, k8s_client: kubernetes.client.CoreV1Api):
    logger.info('Evicting all Pods from Node {node.metadata.name}')
    # https://kubernetes.io/docs/tasks/administer-cluster/safely-drain-node/#the-eviction-api
    while True:
        pod_list = k8s_client.list_pod_for_all_namespaces(
            field_selector=f'spec.nodeName={node.metadata.name}'
        )
        if not pod_list.items:
            return
        for pod in pod_list.items:
            pod_string = 'Pod {pod.metadata.name} in Namespace {pod.metadata.namespace}'
            try:
                logger.info('Evicting {pod_string} from Node {node.metadata.name}')
                k8s_client.create_namespaced_pod_eviction(
                    namespace=pod.metadata.namespace,
                    name=pod.metadata.name,
                    body=kubernetes.client.models.V1beta1Eviction()
                )
            except kubernetes.client.rest.ApiException as e:
                if e.status == 404:
                    logger.warning(f'{pod_string} was not found (deleted by race condition?)')
                elif e.status == 429:
                    logger.warning(f'Unable to evict {pod_string} as it would violate a PodDisruptionBudget')
                elif e.status == 500:
                    logger.warning(f'Unable to evict {pod_string} due to a server error (multiple PodDisruptionBudgets selecting this Pod?)')
                else:
                    logger.exception(f'An error occurred while attempting to evict {pod_string}')