Convert AppleScript date objects to UNIX timestamp or POSIX date format

unix_dates.scpt

-- convert an AppleScript Date object to a POSIX date CCYYMMDDHHmm.SS
on posixDate(datetime)
	-- date -j -f "%A, %B %e, %Y at %I:%M:%S %p" "Tuesday, September 1, 2015 at 11:00:00 AM" +%Y%m%d%H%M
	set command to "date -j -f '%A, %B %e, %Y at %I:%M:%S %p' '" & datetime & "'"
	set command to command & " +%Y%m%d%H%M.%S"
	
	set thePosixDate to do shell script command
	return thePosixDate
end posixDate

-- convert an AppleScript Date object to a UNIX timestamp (seconds since epoch)
on unixDate(datetime)
	set command to "date -j -f '%A, %B %e, %Y at %I:%M:%S %p' '" & datetime & "'"
	set command to command & " +%s"
	
	set theUnixDate to do shell script command
	return theUnixDate
end unixDate

Nice. They've had posix paths forever... just never posix dates.

@darrenpmeyer, thanks for sharing a great set of functions.

I was hoping to use your posixDate() function as a general purpose date formatting function. I changed your arguments to add a "formatCodes" parameter, and replaced your
set command to command & " +%Y%m%d%H%M.%S"
with
set command to command & " +" & formatCodes

It seems to work find, but ignores any codes after a space.

So "%Y-%m-%d" works fine.
But "%Y-%m-%d" %H:%M:%S" does not. The hours, min, and sec are not returned.

Here the complete function with my changes:

set dDate to current date

set strDate1 to formatDate(dDate, "%Y-%m-%d")
set strDate2 to formatDate(dDate, "%Y-%m-%d %H:%M:%S")
set strDate3 to formatDate(dDate, "%Y-%m-%d-%H:%M:%S")

log strDate1
log strDate2
log strDate3

on formatDate(pDate, pstrFormat)
    -- convert an AppleScript Date object to a POSIX date

    set command to "date -j -f '%A, %B %e, %Y at %I:%M:%S %p' '" & pDate & "'"
    set command to command & " +" & pstrFormat

    set thePosixDate to do shell script command
    return thePosixDate
end formatDate

this returns:

(*2015-12-26*)
(*2015-12-26*)
(*2015-12-26-05:09:42*)

Have I done something wrong?
Thanks again for sharing, and for your help.

@JMichaelTX

You need to surround the format string with single-quotes or the shell will see multiple arguments. So do:

set command to "date -j -f '%A, %B %e, %Y at %I:%M:%S %p' '" & pDate & "'"
set command to command & " +'" & pstrFormat & "'"

Thanks.

How can we convert unix time to AppleScript date object?