kube_cronjob_next_schedule_time in the past when cronjob timezone specified

[paulclark222]

What happened:
Defined a timezone for a cronjob:
timeZone: "Europe/London"
Now kube_cronjob_next_schedule_time is always returning the last schedule time rather than the next one.

What you expected to happen:
kube_cronjob_next_schedule_time should be the next scheduled time.

How to reproduce it (as minimally and precisely as possible):
Define a cronjob with non-UTC timezone (may only happen on zones east of UTC). Wait for the job to execute and then check kube_cronjob_next_schedule_time - you will see it's in the past.

• kube-state-metrics version: 2.10
• Kubernetes version (use kubectl version): 1.27
• Cloud provider or hardware configuration: Azure AKS

[dashpole]

/assign @dgrisonnet
/triage accepted

[CatherineF-dev]

The source code is here:

kube-state-metrics/internal/store/cronjob.go

Lines 238 to 263 in b91dd31

	*generator.NewFamilyGeneratorWithStability(
	"kube_cronjob_next_schedule_time",
	"Next time the cronjob should be scheduled. The time after lastScheduleTime, or after the cron job's creation time if it's never been scheduled. Use this to determine if the job is delayed.",
	metric.Gauge,
	basemetrics.STABLE,
	"",
	wrapCronJobFunc(func(j *batchv1.CronJob) *metric.Family {
	ms := []*metric.Metric{}
	// If the cron job is suspended, don't track the next scheduled time
	nextScheduledTime, err := getNextScheduledTime(j.Spec.Schedule, j.Status.LastScheduleTime, j.CreationTimestamp)
	if err != nil {
	panic(err)
	} else if !*j.Spec.Suspend {
	ms = append(ms, &metric.Metric{
	LabelKeys: []string{},
	LabelValues: []string{},
	Value: float64(nextScheduledTime.Unix()),
	})
	}
	return &metric.Family{
	Metrics: ms,
	}
	}),
	),

Could you dive into it and help debug if you are available?

[paulclark222]

I'm not a go developer, but I suspect that what's happening is that j.Spec.Schedule doesn't include the timezone, so the cron library is interpreting it in local time (UTC). So if this code were to run just after the cronjob had run (in UTC+1), it would say the next scheduled time was still 1 hour away.

The cronjob library expects the timezone to be specified like this:
schedule, err := cron.ParseStandard("TZ=America/Los_Angeles 0 2 * * 0")
or
loc, _ := time.LoadLocation("Europe/Paris") cronProcess := cron.New(cron.WithLocation(loc))

I'm not sure if this is being done.

[CatherineF-dev]

Hi @paulclark222, j.Spec does have a field named timezone, which hasn't been used

https://github.com/kubernetes/api/blob/master/batch/v1/types.go#L637

[CatherineF-dev]

Could you ramp up golang and try to fix this issue, if you are available and have enough time?

[dgrisonnet]

The code for the metric predates the support for timezone, so it is not taken into account. We would need to had support for it in ksm.

/help

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In response to this:

The code for the metric predates the support for timezone, so it is not taken into account. We would need to had support for it in ksm.

/help

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[mhmtsvr]

I encountered the same issue after configuring the timezone. Any recent updates or ETA on a resolution? Thanks!