Monit - Allow cron-style negative schedules

[cookiemonsteruk]

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Is your feature request related to a problem? Please describe.
The monit plugin does not currently allow to use negative cron style schedules

Describe the solution you'd like
I would like to be able to enter a negative expression as per the monit official documentation https://mmonit.com/monit/documentation/monit.html#Service-checks

Example 3: Do not run the check in the backup window on Sunday between 0AM to 3AM, otherwise run the check with the regular poll cycle frequency.

check process mysqld with pidfile /var/run/mysqld.pid
not every "* 0-3 * * 0"

Describe alternatives you've considered
As a workaround I have been able to enter * 6-5 * * * where I wanted to enter not every "* 5-6 * * 0" because my goal is to run every minute, every hour, every day, except between hours of 5 and 6, every day, evere month, every day of the week.

Additional context
To reproduce go to create or edit a service in monit UI, enable advanced mode. In "poll time" enter not every * 5-6 * * * or 'not every' * 5-6 * * * or "not every" * 5-6 * * * and I tried a few other permutations and the form sometimes if I recall correctly, errors with validation input. Fair enough.
Sometimes for instance entering not every * 6-5 * * * ends with an entry in /usr/local/etc/monitrc of every "not every * 6-5 * * *" without form validation error but when you investigate you see an entry in the plugin log of:

<!--StartFragment-->
2025-01-15T16:00:43 | Error | monit | /usr/local/etc/monitrc:25: syntax error 'not every'
-- | -- | -- | --

I am contradicting the allowed entry above but I forgot a bit which ones. It matters not, as we can easily see that the form validation does not parse for "Should be a string between 1 and 255 characters. Allowed characters are letters and numbers as well as asterisk, hyphen, comma and space."
Edit: A validation error can be created entering not every "* 6-5 * * *" as an entry attempt.

In summary. I think the current validation unless I have been unable to find the correct way to enter it, does not allow a window to not run the check. Since the underlying code is able to accept it, I hope we can enable those entries.

[cookiemonsteruk]

Addition. If we enter * 6-5 * * * to have an unmonitored window between 05:00 and 06:00 then the monit service starts but this "service setting" stays in status "Waiting" indefinitively.
I have been able to use the alternative workaround of * 6-24,0-5 * * *. Now it goes to "OK" instead of "Waiting".
It would still be very useful to be able to use negative as per monit's code and documentation.