how to add curr timestamp to while loop in container in pod in kubernetes?

Question

apiVersion: v1
kind: Pod
metadata:
  name: pv-pod
  namespace: auth
spec:
  containers:
  - name: busybox
    image: busybox
    #************** HERE is the command!
    command: ['sh', '-c', 'while true; do echo date > /output/output.log; sleep 5; done']
    volumeMounts:
    - name: pv-storage
      mountPath: /output
  volumes:
  - name: pv-storage
    persistentVolumeClaim:
      claimName: host-storage-pvc

This command is where i need to insert into a file "success! Wed Jun 8 20:28:01 WAST 2022",i.e. current timestamp.

command: ['sh', '-c', 'while true; do echo success! $date >> /output/output.log; sleep 5; done']

But it keeps writing 'success date'

Answer 1

You could use command substitution for this. That would be in shell or bash, the same.

Additionally, you may need to escape the dollar sign, since $() has a special meaning in Kubernetes manifests.

echo "success $$(date)" >> ...