How to subtract a date from another date using Robot Framework? - datetime

Question

i'm using Robot Framework Keyword Subtract Date From Date to test that a date is between 2 dates(For example 11/06/2020 is between 07/06/2020 and 20/06/2020), but i'm getting an error in my log file ValueError: Invalid timestamp. The date is a String extracted from a Span Text and i convert it to date This is my code :
${date}= Get Current Date result_format=datetime
${postdate}= Get Text xpath://app-post[1]//div[1]//div[1]//div[1]//div[2]//div[1]//div[2]//div[1]//div[2]//span[2]
${postdate}= Convert Date ${postdate} date_format=%d/%m/%y
${date}= Convert Date ${date} result_format=%d/%m/%y
${temp} = Subtract Date From Date ${postdate} ${date}
Should Be True ${temp}>=0

Answer 1

The problem is you don't follow the allowed format for the keyword Subtract Date From Date mentioned here: https://robotframework.org/robotframework/latest/libraries/DateTime.html#Date%20formats
%y will give you 20, but that obviously is not enough. If I change it to %Y, it will give me 2020 for the current year, and the keyword Subtract Date From Date doesn't complain anymore about invalid timestamp. You'd also need to change it to something like date_format=%Y/%m/%d, that is to change the order of %Y, %m, and %d.
EDIT:
I can now see you're also using date_format as well as result_format with Convert Date. That's another bug in your code, you need to use result_format with both.
EDIT 2:
The full working example:
(And you're not using BuiltIn library here, these datetime keywords are from DateTime library)

Answer 2

The below script worked (Used the static PAST_DATE to check the sample run ):
${date}= Set Variable 21
${month}= Set Variable 12
${year}= Set Variable 2019
${PAST_DATE}= BuiltIn.Catenate SEPARATOR=/ ${year} ${month} ${date}
Log ${PAST_DATE}
${CURRENT_DATE}= Get Current Date result_format=%Y/%m/%d
Log ${CURRENT_DATE}
${DIFFERNCE_IN_DAYS}= Subtract Date from Date ${CURRENT_DATE} ${PAST_DATE} verbose
Log ${DIFFERNCE_IN_DAYS}
#{total_days}= Split String ${DIFFERNCE_IN_DAYS}
${final_days}= Set Variable ${total_days[0]}
Log ${final_days}
Should be true ${final_days} >= 0