Kubernetes Python Client : update deployment spec with affinity-CodePudding

from kubernetes import client, config
config.load_kube_config()
api = client.AppsV1Api()

deployment = api.read_namespaced_deployment(name='foo', namespace='bar')

i tried to add affinity object to deployment spec i got this error

deployment.spec.affinity.nodeAffinity.requiredDuringSchedulingIgnoredDuringExecution.nodeSelectorTerms = [{'nodeSelectorTerms':[{'matchExpressions':[{'key': 'kubernetes.io/hostname','operator': 'NotIn','values': ["awesome-node"]}]}]}]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'V1DeploymentSpec' object has no attribute 'affinity'

CodePudding user response：

You're looking at the wrong place. Affinity belongs to pod template spec (deployment.spec.template.spec.affinity) while you're looking at deployment spec (deployment.spec.affinity).

Here's how to completely replace existing affinity (even if it's None):

from kubernetes import client, config
config.load_kube_config()
api = client.AppsV1Api()

# read current state
deployment = api.read_namespaced_deployment(name='foo', namespace='bar')

# check current state
#print(deployment.spec.template.spec.affinity)

# create affinity objects
terms = client.models.V1NodeSelectorTerm(
    match_expressions=[
        {'key': 'kubernetes.io/hostname',
         'operator': 'NotIn',
         'values': ["awesome-node"]}
    ]
)
node_selector = client.models.V1NodeSelector(node_selector_terms=[terms])
node_affinity = client.models.V1NodeAffinity(
    required_during_scheduling_ignored_during_execution=node_selector
)
affinity = client.models.V1Affinity(node_affinity=node_affinity)

# replace affinity in the deployment object
deployment.spec.template.spec.affinity = affinity

# finally, push the updated deployment configuration to the API-server
api.replace_namespaced_deployment(name=deployment.metadata.name,
                                  namespace=deployment.metadata.namespace,
                                  body=deployment)