I tried using this specification:
apiVersion: batch / v1beta1
kind: CronJob
metadata:
name: test
spec:
schedule: “*/1 * * * *”
concurrencyPolicy: “Forbid”
failedJobsHistoryLimit: 10
startingDeadlineSeconds: 600 # 10 min
jobTemplate:
spec:
backoffLimit: 0
activeDeadlineSeconds: 3300 # 55 min
template:
spec:
containers:
-name: hello
image: python: 3.6 – slim
command: [“python”]
args: [“./main.py”]
restartPolicy: Never
The simple pythonhello world script is being taken further. This example creates a container containing a hello world python script and it is deployed as a CronJob to a cluster using helm.
kubectl – n
default create serviceaccount tiller
kubectl create clusterrolebinding tiller\
–clusterrole cluster – admin\
–serviceaccount =
default: tiller
helm init–service – account tiller–tiller – namespace
default
docker build – t python – helloworld: v1.
apiVersion: batch / v1beta1
kind: CronJob
metadata:
name: {
{
.Values.cronjob.name
}
}
labels:
app.kubernetes.io / name: {
{
.Values.cronjob.name
}
}
helm.sh / chart: {
{
include “python-helloworld.chart”.
}
}
spec:
schedule: “{{ .Values.cronjob.schedule }}”
jobTemplate:
spec:
template:
spec:
containers:
-name: {
{
.Chart.Name
}
}
image: “{{ .Values.image.repository }}:{{ .Values.image.tag }}”
restartPolicy: OnFailure
image:
repository: “python-helloworld”
tag: “v1”
pullPolicy: IfNotPresent
cronjob:
name: python – helloworld
schedule: “*/1 * * * *”
I had originally planned to run bash script anycodings_kubernetes which could do:
txt ,In short I want to be able to run k8s anycodings_kubernetes CronJob which can run Python script by first anycodings_kubernetes installing requirements and then running it,where is the startup script.
/main.py anycodings_python located? is it present in the image. you anycodings_python need to build new image using anycodings_python python:3.6-slim as base image and add anycodings_python your python script to PATH.
then you anycodings_python would be able to run it from k8s CronJob
I Rried Using This Specification:
apiVersion: batch / v1beta1
kind: CronJob
metadata:
name: test
spec:
schedule: “*/1 * * * *”
concurrencyPolicy: “Forbid”
failedJobsHistoryLimit: 10
startingDeadlineSeconds: 600 # 10 min
jobTemplate:
spec:
backoffLimit: 0
activeDeadlineSeconds: 3300 # 55 min
template:
spec:
containers:
-name: hello
image: python: 3.6 – slim
command: [“python”]
args: [“./main.py”]
restartPolicy: Never
One CronJob object is similar to one line of a crontab file. Cron format is used to write a job periodically on a schedule. ,A CronJob creates Jobs on a repeating schedule.
,To generate CronJob schedule expressions, you can also use web tools like crontab.guru. ,CronJob is a part of the Kubernetes platform.
You should read the CronJob object definition to understand the Kubernetes cron jobs.
apiVersion: batch / v1
kind: CronJob
metadata:
name: hello
spec:
schedule: “* * * * *”
jobTemplate:
spec:
template:
spec:
containers:
-name: hello
image: busybox: 1.28
imagePullPolicy: IfNotPresent
command:
-/bin/sh –
-c –
date;
echo Hello from the Kubernetes cluster
restartPolicy: OnFailure
apiVersion: batch / v1
kind: CronJob
metadata:
name: hello
spec:
schedule: “* * * * *”
jobTemplate:
spec:
template:
spec:
containers:
-name: hello
image: busybox: 1.28
imagePullPolicy: IfNotPresent
command:
-/bin/sh –
-c –
date;
echo Hello from the Kubernetes cluster
restartPolicy: OnFailure
Cron Schedule Syntax
#┌───────────── minute(0 – 59)
#│┌───────────── hour(0 – 23)
#││┌───────────── day of the month(1 – 31)
#│││┌───────────── month(1 – 12)
#││││┌───────────── day of the week(0 – 6)(Sunday to Saturday; #│││││ 7 is also Sunday on some systems)
#│││││ OR sun, mon, tue, wed, thu, fri, sat
#│││││
# * * * * *
Every CronJob has a CronJob Controller that checks how many times it missed a schedule. If there are more than 100 missed schedules, then the job won’t start.
Cannot determine
if the job needs to be started.Too many missed start time( > 100).Set or decrease.spec.startingDeadlineSeconds or check clock skew.
