Article on how to schedule an integration flow using CRON expressions.

[drobiazko]

Collection: How-to Guides
Section: Building integration flows

The article should explain how to schedule an integration flow using CRON expressions.

[al3xive]

---

title: Scheduling a flow with CRON
layout: article
section: Building integration flows
category: component
order: 4
since: 20181218

Scheduling tasks are part of the Elastic Platform's functionality. In this article, we are going to cover the scheduling scenario using CRON.

What is CRON

CRON is the UNIX-like job scheduler that executes commands or scripts at given time and date.
CRON is driven by a cron table, to run periodically on a given schedule. See the crontab line on the screenshot below:

Please Note: By default, our System repeats the flow's execution every 3 minutes. However, you are free to customize the time range according to your needs.

The line's syntax expects a CRON expression made of five values. For more information on how to generate CRON's expressions, please follow this link.

The Scheduling

Please be aware, that changing the flow's schedule means modifying the flow. Here some of the requirements to follow:

• For modifying a flow, you should have specific permissions.
• As soon as you modify the flow's schedule, you should restart it to let the System apply the changes.

To proceed further with CRON scheduling follow the steps below:

First step

Create a flow or pick the existing one by navigating to the Workspace > Flows > Choose the necessary Flow > Settings tab. See the screenshot below.

Second step

The Scheduling tab consists of the Cron Expression section and the Next Occurrences one.

Specify the necessary value into the Minute field that is under the Cron Expression title. For example, we want to restart the flow every minute, so we type in the following */1 value. The Next Occurrences section represents the result. Check the screenshot below.

Please Note: By default, the Cron Expression section's value is always in the GMT format. The Next Occurrences section converts the specified GMT value into your Local Time format one. This way it demonstrates the expected result, so you can make sure it is correct.

In case of mistake or wrong value, the System displays an Error Message.

Below are some predefined scheduling definitions:

Description	Equal to
Run once at every 5th minute	*/5 * * * *
Run once at every 10th minute	*/10 * * * *
Run once every hour at minute 0	0 * * * *
Run once every day at midnight 00:00	0 0 * * *
Run once every week at 00:00 on Sunday	0 0 * * 0
Run every month at 00:00 on day-of-month 1	0 0 1 * *
Run every year at 00:00 on day-of-month 1 in January	0 0 1 1 *

To find more definitions, please follow this link.

Third step

Once you finish the setup, click the Save button to apply the changes. The Successfully updated the flow scheduling text message appears in the upper right corner.

Fourth step

Now let's publish our Draft. To do that, please navigate back to the Graph tab and click the Publish Draft button. Once it's done, start the flow by clicking the green play-icon on your right.

Please Note: In case of a Webhook flow, there won't be any CRON Scheduling available. See the screenshots below for more information.

This is how you schedule your flow with CRON in the Elasticio's Platform.

[al3xive]

scheduling-flow-using-cron.md.zip

[al3xive]

Images used in the article
cron.zip

[drobiazko]

@al3xive why don't you just create a pull request?

[khanzadyan]

This is done. Closing it.