pub const JOB_NAME_MAX: usize = 57;Expand description
The longest Job name that stays valid once Kubernetes derives child object
names from it (#547): 57, not 63.
Kubernetes 1.37’s WorkloadWithJob creates a pod-group template named
<job>-pgt-0 for each Job, and that name must itself fit the 63-character
DNS-label limit, so a Job name may use at most 63 - len("-pgt-0") = 57.
(Pod names are not the constraint: they come from generateName, which the
apiserver truncates.) Generated Job names are capped to this; a Job whose name
IS a user-chosen CR name (a Snapshot’s backup Job, a Restore’s Job) cannot
be renamed, so admission warns when such a name is longer.