Wait Node with a function in Specified Time

Questions
,
1

Describe the problem/error/question

I’m trying to send an HTTP request 1 hour before a date and time that I receive in a webhook. I’m transforming it to ISO format, but it’s not working. I don’t know why.

What is the error message (if any)?

No erro message. The workflow just keep going forever until i stop.

Please share your workflow

I’m leving here the test that i’m making because the error is the same.

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Share the output returned by the last node

The node just wait forever and does nothing

Information on your n8n setup

  • n8n version:
    1.31.1
  • Database (default: SQLite):
  • n8n EXECUTIONS_PROCESS setting (default: own, main):
  • Running n8n via (Docker, npm, n8n cloud, desktop app):
  • Operating system:
2

hello @Coders_Club

What does it mean? You can’t send anything in the past…

Can you share the workflow?

3

The date that I receive in the webhook is the date of a scheduled call, and I want to remind the participants 1 hour before the call.

4

In the test I’m sharing, I picked the current date and added 1 minute to test and still no working.

5

In that case, the webhook must receive that data earlier than 1 hour before the call. E.g. receive it 1 hour 10 minutes before the call, wait for 10 minutes and send a reminder.

To share the workflow, select all nodes (or hit ctrl+a), then past the content here after clicking the button </>
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Workflow for tests, that will remind 2 minutes before the call. To check - open the https://www.unixtimestamp.com/ and create a conversion, that will be in 3-4 minutes

Click on the red text below the workflow and hit “Copy”, then ctrl+v in the workflow window to past it

6

That is what i was doing:

Your way works but why my way dont work?

7

Because the Wait node works with seconds (or other measurable time entity), it does not work with timestamps.

That formula

{{ $json.DataHoraNova.seconds -3600}}

will evaluate the date and substitute an hour from it (in theory). Thus, it will return a new date (e.g. 2024-03-12T20:33:38+01:00), but the Wait node can’t work with it, the date will be treated as a timestamp (e.g. 1710276600, so it waits for that amount of seconds. It’s about ~55 years to wait :slight_smile: )

You should provide the number of seconds to Wait for (e.g. 10 - wait for 10 seconds only) or you have to change the operation to “At Specified Time”.
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But for that, your date should be converted into date type

{{ DateTime.fromISO($json.DataHoraNova).minus({ "seconds": 3600 })}}
8

First of all, you are helping me a lot, so thanks a lot.
Secondly, actually I sent the wrong workflow that I was testing. I was doing what you said with ‘Specified Time’, but it still doesn’t work.

I tried with node code too but I’m still missing the point somewhere. Again, thanks a lot.

9

I think is the brazilian format of date

10

Hm.. It’s acting very weird with that action and an expression as a value.
It will work only with the date in the below format (see the workflow in the end):

{{ DateTime.fromISO($json.DataIso).toFormat("yyyy-MM-dd'T'TT") }}

Moreover, that flow has an internal error with the dates

@Jon can you check this out? Seems the Wait node has not been designed for such a case.
Error says

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And if I set the date with an expression in the same format, than it seems everything is working fine, except in the executions we will see some weird waiting time
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