is it possible to automate rules for due dates for checklist items based on card start and due dates

[Neta Zilberman]

is it possible to automate rules for due dates for checklist items based on card start and due dates?

[DiMaggio Tucci]

To my knowledge...it depends on what you want to do, but it's not easy, regardless.

I don't think there's a way to read the due date directly off of a checklist item for automations, except (maybe) by using the API. However, you can write a due date to an item, or add/remove it, and you can read the due date off a a card that represents and refers to the checklist item, and possibly do automation with it that way.

In order to edit the due date on an existing checklist item, you would have to remove the item and add it back, since you can only "pull" a checklist item to add or remove it, not edit it.

In order to get a due date to add to an item or get an item name to "pull", it would need to exist on a card somewhere. So everything you're doing to a checklist item would have to be represented on a card somewhere.

You would need to make heavy use of Finding Cards , Automation Variables, and Pattern Matching/Wildcards. 

If you give a more specific need, I can try and let you know if I can figure out a way to do it. It's a big workaround, so specific needs are needed to make it work for you.

EDIT: From basic research, it looks like you could do a lot more with the API, but that is also a whole other can of worms if you're not experienced with it.

[Neta Zilberman]

Thanks @DiMaggio Tucci ! I am very inexperienced with Trello, but am trying to set up some rules. The idea is that I want to assign due dates to tasks based on the start date and due date of the card. So lets say I have a card Start date = S and a card Due date = D. I want to assign Task #1 a due date of S+3, and for Task #2 I want to assign a Due date of D-12.

Is that helpful to understanding what I'm trying to do?

[DiMaggio Tucci]

Yes, it is helpful. However, that is definitely a tricky one, even for an experienced user. Most on Google just say it's not possible to work with checklist due dates, and the way I've done it is pretty...hacky haha!

Can you add this information to the checklist item itself? Would that make it too much extra work for what you're trying to do anyways? For instance:

"Checklist Item Name Due Date -12" (without quotes)

(By the way, if you wanted to ADD instead of SUBTRACT, you don't need a '+'. You would just type "12")

If so, I just tested this:

when an item containing "{?} Due Date {* }" is added to a checklist, set custom field "Logic Name" to "{checklistitemname}", set custom field "Logic Checklist" to "{checklistname}", set date custom field "Logic Date" to now, and move the date in custom field "Logic Date" by {wildcard2} days

If a checklist item is added that has some text, a space, the words "Due Date", a space, and then more text, then store the whole checklist item name and checklist name in custom fields. Use the end of the text to add or subtract the number of days from the card's due date, and set a custom field with that value.

when custom field "Logic Date" is set, remove item "{{%Logic Name}}" from checklist "{{%Logic Checklist}}", add item "{{%Logic Name}}" to checklist "{{%Logic Checklist}}", and set the item due on the date in custom field "Logic Date"

We must remove the checklist item first. Then we add it again, using the custom field data, and set the due date to match.

And this sets the due date on the item to be 12 days before the card due date, in the example I gave earlier.

You would need to add these automations for the start date, too.

This would only work when you create a checklist item; it won't trigger if you're renaming an existing one. You have to get it right!

If you don't want the custom fields on your cards, you can move this information to another card with the name {cardlink}, even on another board if you'd like. Then, when the Logic Date is updated on that card, use the name of the card to pull up the original card and do the same on the checklist item there.

It's hacky, but I tested it, and it works! Hope this helps!

[DiMaggio Tucci]

@Neta Zilberman