[bug] during daylight saving time change Cronical sleep for one hour

[StefanoTesla]

If this repo is the Cronical that is included in Laragon we have a problem.

https://github.com/leokhoa/laragon/issues/898

I have a laravel application and I use cronical installed as service (I'm on windows) to make the scheduler running.

When daylight saving time ends in winter, the clocks go back from 3:00 to 2:00, meaning we experience the 2 hour twice.

What append:

2024-10-27 02:57:00.943       [10] Starting job: C:\laragon\www\ascomconnector\schedule.bat
2024-10-27 02:58:01.708       [21] Starting job: C:\laragon\www\ascomconnector\schedule.bat
2024-10-27 02:59:01.494       [20] Starting job: C:\laragon\www\ascomconnector\schedule.bat
2024-10-27 03:00:01.352       [20] Starting job: C:\laragon\www\ascomconnector\schedule.bat
2024-10-27 03:01:01.136       [21] Starting job: C:\laragon\www\ascomconnector\schedule.bat
2024-10-27 03:02:00.903       [10] Starting job: C:\laragon\www\ascomconnector\schedule.bat

What I expected:

2024-10-27 02:57:00.943       [10] Starting job: C:\laragon\www\ascomconnector\schedule.bat
2024-10-27 02:58:01.708       [21] Starting job: C:\laragon\www\ascomconnector\schedule.bat
2024-10-27 02:59:01.494       [20] Starting job: C:\laragon\www\ascomconnector\schedule.bat
-----HERE ANOTHER 2:XX HOUR BUT CRONICAL SLEEP-----
2024-10-27 03:00:01.352       [20] Starting job: C:\laragon\www\ascomconnector\schedule.bat
2024-10-27 03:01:01.136       [21] Starting job: C:\laragon\www\ascomconnector\schedule.bat
2024-10-27 03:02:00.903       [10] Starting job: C:\laragon\www\ascomconnector\schedule.bat

[StefanoTesla]

I'm a noob in C#, but looking around everyone talk about problems using DateTime looking to the MSDN documentation:

Conversion operations between time zones (such as between UTC and local time, or between one time zone and another) take daylight saving time into account, but arithmetic and comparison operations do not.

From what I'm reading everyone suggest to implement Noda Time library

[mgefvert]

Hi! Cronical is not currently under active development. Having said that, I might possibly be able to find some time to look at it, but I can't guarantee the time frame, unless you're able to submit a patch or pull request yourself.

NodaTime is an excellent library, but it doesn't magically solve the problem that there is, actually, a 2:30am happening twice on that day.

One possible solution would be to express time internally as UTC inside Cronical, and keep converting input and output data to and from that. This would ensure that time is strictly sequential in the internal classes; however, it may have some unforeseen side effects (I'll have to think through exactly what that means).

Another is to simply keep track of DST transitions and, like you suggested, refuse to run jobs through that interval - this may be the cleanest solution actually.

[StefanoTesla]

I read about that library but I don't know if it's right or not.

Anyway I think the best approach is to express time internally as UTC, if for example I want to run a job at 2.30 during DTS for sure it will be handled just one time, please explain const...

I can track dts, but in the case the time come back like in October the cronical don't run, but it should run....when we pass the hour probably we don't have this problem cause he will see actual time > then wait time

[StefanoTesla]

I tried to open the project with vscode, but I can't find the DotNetCommons can you help me?

[mgefvert]

DotNetCommons is another repository of mine; but it should be available as a git submodule - if you fork the repository and make sure to recurse into submodules, you should be getting it properly. Personally I'd recommend JetBrains Rider over vscode, it's supposed to be free now for noncommercial work.

[alxndr-w]

Maybe, as a workaround, a cron that updates the cron-file right at 03:00:00 daylight saving day will bring Cronical to just continue.