You can execute short-lived workflows by running them as Tasks. Running Tasks describes how to run Tasks under Apps.
You can also schedule Tasks to run at recurring intervals specified using the unix-cron format. With scheduled Tasks, you first push an App running the Task as you do with an unscheduled Task, and then create a Job to schedule the Task.
You can define a schedule so that your Task runs multiple times a day or on specific days and months.
Push an App for running scheduled Tasks
Clone the test-app repo:
git clone https://github.com/cloudfoundry-samples/test-app test-app
cd test-app
Push the App.
Push the App with the
kf push APP_NAME --task
command. The--task
flag indicates that the App is meant to be used for running Tasks, and thus no routes will be created on the App and it will not be deployed as a long-running application.kf push test-app --task
Confirm that no App instances or routes were created by listing the App:
kf apps
Notice that the App is not started and has no URLs:
Listing Apps in Space: test-space Name Instances Memory Disk CPU URLs test-app stopped 1Gi 1Gi 100m <nil>
Create a Job
To run a Task on a schedule, you must first create a Job that describes the Task:
kf create-job test-app test-job "printenv"
The Job starts suspended or unscheduled, and does not create Tasks until it is
manually executed by kf run-job
or scheduled by kf schedule-task
.
Run a Job manually
Jobs can be run ad hoc similar to running Tasks by kf run-task
. This option
can be useful for testing the Job before scheduling or running as needed in addition
to the schedule.
kf run-job test-job
This command runs the Task defined by the Job a single time immediately.
Schedule a Job
To schedule the Job for execution, you must provide a unix-cron schedule in the
kf schedule-job
command:
kf schedule-job test-job "* * * * *"
This command triggers the Job to automatically create Tasks on the specified schedule. In this example a Task runs every minute.
You can update a Job's schedule by running kf schedule-task
with a new schedule.
Jobs in Kf can only have a single cron schedule. This differs
from the PCF Scheduler, which allows multiple schedules for a single Job.
If you require multiple cron schedules, then you can achieve that with multiple Jobs.
Manage Jobs and schedules
View all Jobs, both scheduled and unscheduled, in the current Space by using
the kf jobs
command:
$ kf jobs
Listing Jobs in Space: test space
Name Schedule Suspend LastSchedule Age Ready Reason
test-job * * * * * <nil> 16s 2m True <nil>
unscheduled-job 0 0 30 2 * true 16s 2m True <nil>
Additionally, you can view only Jobs that are actively scheduled with
the kf job-schedules
command.
$ kf job-schedules
Listing job schedules in Space: test space
Name Schedule Suspend LastSchedule Age Ready Reason
test-job * * * * * <nil> 16s 2m True <nil>
Notice how the unscheduled-job
is not listed in the kf job-schedules
output.
Cancel a Job's schedule
You can stop a scheduled Job with the kf delete-job-schedule
command:
kf delete-job-schedule test-job
This command suspends the Job and stops it from creating Tasks on the previous schedule.
The Job is not deleted and can be scheduled again by kf schedule-job
to continue execution.
Delete a Job
The entire Job can be deleted with the kf delete-job
command:
kf delete-job test-job
This command deletes the Job and all Tasks that were created by the Job, both scheduled and manual executions. If any Tasks are still running, this command forcefully deletes them.
If you want to ensure that running Tasks are not interrupted, then first delete
the Jobs schedule with kf delete-job-schedule
, wait for all Tasks to complete,
and then delete the job by calling kf delete-job
.