How to handle daylight savings time when calculating time/date

Question

Hello everyone! I have run across an interesting issue. I created a form which my users use a calendar pull down to select a date in the future. When they select the start date, I calculate the end date for 7 days later and adding an additional 7 hours to the end date so the end time would show 2022-02-07 07:00.

When my users select 2022-03-07 as a start date the end date gets set

2022-03-14 08:00

when it should be 2022-03-14 07:00.

Since our daylight savings time starts 2022-03-13 I'm wondering how I can programmatically work this field calculation for this one specific issue. I know this is also probably going to happen when our DST ends. So is there any way I can fix this little annoyance?

This is how I set the field.....

OnCallEnd=[entry.BeginDate.timestamp.add(604800000+25200000).formatDate(yyyy-MM-dd HH:mm)]

the 604800000 is 7 days ahead and the 25200000 is 7 hours ahead. I tried to set the timezone to the formatDate but that didn't help.

Any help in this little annoyance would be appreciated.

Thanks.

Glen

Alex Medved _ConfiForms_ · Answer

Hi

Honestly, I am quite puzzled by this complexity and probably not getting the whole reasoning behind it, but...

If you know when you need to calculate the end date adding another hours then I suggest to make the calculation conditional, based on that.

So, basically having two functions - one that calculates your end date before the certain date and another one that calculates it after

Alex

Glen Collins_txqz3m · Answer

This is within confiforms and not a user macro. The calculation is done when the date dialog is closed and it then performs the calculations based upon the data I have provided. I don't know if confiforms uses it own method of determining daylight savings or if they rely on confluence to do this. All I know is it starts one week before the actual time change takes place. But I'm just worried about monday as this is the specific day users are allowed to select.

This is a minor annoyance and I've just notified my users to watch out for this twice a year.

Thanks.

Glen

Bill Bailey · Answer

Is this via a user macro? In other words, is the calculation rendered each time the page is refreshed?

Does your server time adjust for DST? In other words, can you detect the change by the server time zone marker?

Otherwise, you either have to a) live with the edge cases 2 weeks out of the year, or b) you have to programmitaclly keep track of the dates the times change and do your own adjustment (not pretty, but workable).