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I've understood AWS Cloudwatch Scheduled Rules (Amazon EventBridge Rules) which works by defining CRON expression.

The documentation mentions rules that triggers repetitively on a given time. Such as, run a Cloudwatch rule every 15 mins and so on.

What I want is a Rule that runs only ONCE. Any ways to achieve it? For example, run a rule after 1 hour from now, and thereafter it should never run.

Any solution?

PS: I've checked event based rule also but I don't have any event that can trigger rule.

Tejaskumar
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  • You can make your code create a cloudwatch rule that runs every hour and then on the first trigger delete that rule again. – luk2302 Mar 02 '21 at 12:53
  • what actually that target for that Rule? if it's one time, perhaps we can directly trigger that target rather than having a rule? – Balu Vyamajala Mar 02 '21 at 13:07

2 Answers2

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You can use a CRON expression in CloudWatch Events (or EventBridge) that only specifies one point in time by simply not using wildcards/repeats in the CRON expression.

For example, run a rule after 1 hour from now, and thereafter it should never run.

While you cannot directly express "one hour from now on" in a CRON expression, you can build a CRON expression that will specify that absolute point in time, such as:

cron(0 15 2 3 ? 2021)

if today were the second of March 2021, at 14:00 o'clock. So, this is the CRON expression you'd use to say "one hour from now".

httpdigest
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You can use the new AWS EventBridge Scheduler feature

https://www.beabetterdev.com/2022/11/12/aws-eventbridge-scheduler-tutorial/?_gl=1*f8oym1*_ga*MTU0MTE2NjgxOC4xNjc4ODk4NjE2*_ga_9YXSREER7T*MTY3ODg5ODYxNS4xLjAuMTY3ODg5ODYxNS4wLjAuMA..&_ga=2.4920816.2115715245.1678898616-1541166818.1678898616

https://aws.amazon.com/blogs/compute/introducing-amazon-eventbridge-scheduler/

ekeren
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