list_empty_nodes.py

""" Emit all nodes (with an optional label selector) that have no pods running except for daemonsets
"""
import sys
from kubernetes import client, config

config.load_kube_config()

node_label_selector = ''
if len(sys.argv) == 2:
    node_label_selector = sys.argv[1]
else:
    assert len(sys.argv) == 1

v1 = client.CoreV1Api()
response = v1.list_node(label_selector=node_label_selector)
for node in response.items:
    field_selector = f'spec.nodeName={node.metadata.name},status.phase!=Succeeded'
    pods = v1.list_pod_for_all_namespaces(field_selector=field_selector)
    for pod in pods.items:
        owner_references = pod.metadata.owner_references
        if owner_references is None or len(owner_references) != 1 or owner_references[0].kind != 'DaemonSet':
            break
    else:
        print(node.metadata.name)