Sending Slack message when a value from sheet is in next week (Apps Script - Slack incoming webhooks)

Question

I'm trying to utilize slack incoming webhooks to let my teammates know the information of new hires written in sheet at the designated time.

At 3rd column, I write the first date of each new hire. And want to share info of new hires a week before the first date, at certain time.

For example, if there are 3 new hires on 2nd Monday of August, I'd like to let slack bot share the info at 1st Monday of August, 10:00am KST.

Looks like I need to use formatted_date value to send out auto message a week earlier. How would I make it possible?

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Answer 1

If you are looking to schedule a message on Slack using an app you won't be able to do it using a webhook. I'd recommend using a bot token and making an API call to chat.scheduleMessage instead.