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cronjob: handle invalid/unschedulable dates#26
Merged
tomwans merged 1 commit intolyft:release-1.16.15-lyft.1from Feb 9, 2021
Merged
cronjob: handle invalid/unschedulable dates#26tomwans merged 1 commit intolyft:release-1.16.15-lyft.1from
tomwans merged 1 commit intolyft:release-1.16.15-lyft.1from
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There is a case for tricky cron schedules, like 0 0 31 2 *, which intends to run on Feb 31st. This date does not exist at the moment, which can cause the earliest-missed-deadline math go into an infinite loop. Thankfully, the cron library returns a "zero date" when a next schedule is not found within 5 years: https://github.com/robfig/cron/blob/6a8421bcff44c2a9889075724070baaebf8dcd72/spec.go#L87-L88 We rely on seeing this zero date and short-circuit out of our recursive algorithm.
ashleycutalo
approved these changes
Feb 9, 2021
This was referenced Sep 20, 2021
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There is a case for tricky cron schedules, like 0 0 31 2 *, which
intends to run on Feb 31st. This date does not exist at the moment,
which can cause the earliest-missed-deadline math go into an infinite
loop.
Thankfully, the cron library returns a "zero date" when a next
schedule is not found within 5 years:
https://github.com/robfig/cron/blob/6a8421bcff44c2a9889075724070baaebf8dcd72/spec.go#L87-L88
We rely on seeing this zero date and short-circuit out of our
recursive algorithm.