Check whether an user input is a valid date or not

[smanjunath211]

I have a telegram bot which connects to my node-red and triggers a flow which generates a report. for it to work correctly, i need the user to always input the date format in YYYY-MM-DD format, when the user enters correctly, it generates a report and sends a report back to telegram.
however if the user sends an incorrect syntax, the report obviously doesnt generate, i want to send the user a message the syntax was incorrect.

is there a way to

1. check if the entered string is a valid date in the format YYYY-MM-DD and/or
2. restrict the user to enter always in the given format. or
3. generate a inline keyboard in telegram whcih is similar to a datepicker. (raised a separate topic in forum already)

any help / hint appreciated.

[E1cid]

Here is a posibility

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[edit]
$moment().isAfter()
May work better if you want to limit valid dates by years.

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Will return true or false

[smanjunath211]

this would satisfy my urgent need. thanks!
I understand the logic behind it, but would never be able to build a equation with jsonata like this. ever.
my ulterior goal is to get some 'datepicker' interface in telegram. still searching for it.

[drmibell]

Another approach, while you search, might be to use the node-red-contrib-moment node to force conversion to the format you want. Since it would let the user enter a "wrong" format, it might be best to show what the node thinks he wants and ask for confirmation. (Note the difference in how "24-05-223" is handled.)

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