Kubernetes - Job scheduling API - kubernetes

Question

I am trying to schedule Jobs in Kubernetes.
https://kubernetes.io/docs/concepts/workloads/controllers/cron-jobs/
The job can be created using the below command.
$ kubectl create -f ./cronjob.yaml
cronjob "hello" created
Is there any REST API using which the Job can be created from a Java client?
Thanks

Answer 1

The respective REST endpoint is described in the official API reference. You will find the CronJob resource in the batch/v1beta1 API group. To create a new CronJob resource, you'll need a POST call to the /apis/batch/v1beta1/namespaces/{namespace}/cronjobs URL.
A respective HTTP request might look something like this:
POST /apis/batch/v1beta1/namespaces/default/cronjobs HTTP/1.1
Content-Type: application/json
Content-Length: ...
Authorization: ...
[other headers]
{
"metadata": {
"name": "some-cron"
},
"spec": {
...
}
}
There are also older versions of the same resource, for example in the batch/v2alpha1 API group. As a rule of thumb, I'd recommend using the newest API version available to you. Especially, do not rely on alpha APIs in production; they tend to deprecate pretty quickly between releases.
To create a batch/v1beta1 CronJob using the Java client, have a look at the createNamespacedCronJob method of the io.kubernetes.client.openapi.apis.BatchV1beta1Api class.

Answer 2

HTTP Request
POST /apis/batch/v1beta1/namespaces/{namespace}/cronjobs
You can take a look here for API overview: cronjob-v1beta1-batch
Add CronJob object in request Body.
{
"apiVersion": "batch/v1beta1",
"kind": "CronJob",
"metadata": {
"name": "hello"
},
"spec": {
"schedule": "*/1 * * * *",
"jobTemplate": {
}
}
}
Check here its spec: writing-a-cron-job-spec
Part of swagger.json
"post": {
"description": "create a CronJob",
"consumes": [
"*/*"
],
"produces": [
"application/json",
"application/yaml",
"application/vnd.kubernetes.protobuf"
],
"schemes": [
"https"
],
"tags": [
"batch_v1beta1"
],
"operationId": "createBatchV1beta1NamespacedCronJob",
"parameters": [
{
"name": "body",
"in": "body",
"required": true,
"schema": {
"$ref": "#/definitions/io.k8s.api.batch.v1beta1.CronJob"
}
}
],
"responses": {
"200": {
"description": "OK",
"schema": {
"$ref": "#/definitions/io.k8s.api.batch.v1beta1.CronJob"
}
},
"201": {
"description": "Created",
"schema": {
"$ref": "#/definitions/io.k8s.api.batch.v1beta1.CronJob"
}
},
"202": {
"description": "Accepted",
"schema": {
"$ref": "#/definitions/io.k8s.api.batch.v1beta1.CronJob"
}
},
"401": {
"description": "Unauthorized"
}
},
"x-kubernetes-action": "post",
"x-kubernetes-group-version-kind": {
"group": "batch",
"kind": "CronJob",
"version": "v1beta1"
}
}
See full swagger.json