Kubernetes - Tell when Job is Complete

问题:

I'm looking for a way to tell (from within a script) when a Kubernetes Job has completed. I want to then get the logs out of the containers and perform cleanup.

What would be a good way to do this? Would the best way be to run kubectl describe job <job_name> and grep for 1 Succeeded or something of the sort?

回答1:

You can visually watch a job's status with this command:

kubectl get jobs myjob -w

The -w option watches for changes. You are looking for the SUCCESSFUL column to show 1.

For waiting in a shell script, I'd use this command:

until kubectl get jobs myjob -o jsonpath='{.status.conditions[? 
    (@.type=="Complete")].status}' | grep True ; do sleep 1 ; done

回答2:

You can now do:

kubectl wait --for=condition=complete job/myjob

and you can also set a timeout:

kubectl wait --for=condition=complete --timeout=30s job/myjob

回答3:

You can use official Python kubernetes-client.

https://github.com/kubernetes-client/python

Create new Python virtualenv:

virtualenv -p python3 kubernetes_venv activate it with

source kubernetes_venv/bin/activate

and install kubernetes client with:

pip install kubernetes

Create new Python script and run:

from kubernetes import client, config

config.load_kube_config()

v1 = client.BatchV1Api()
ret = v1.list_namespaced_job(namespace='<YOUR-JOB-NAMESPACE>', watch=False)
for i in ret.items:
    print(i.status.succeeded)

Remember to set up your specific kubeconfig in ~/.kube/config and valid value for your job namespace -> '<YOUR-JOB-NAMESPACE>'