Robot Framework — Generating Random Dates of birth

I’m a big fan of Robot Framework an automated browser testing framework written in Python making use of Selenium. If you haven’t tried it then I suggest giving it a go.

Anyway I had the need to create random data and one of these fields was a date for birth. I also needed the ability to have a minimum date of birth, so I hacked together the following snippet to do this.

Please note that this function has the following limitations

• a maximum date of birth of Jan 1 1970 (as I use the epoch timestamp)
• For similar reasons you can’t overflow at the other end past 2038.
• The minimum age isn’t strictly enforced. Ideally it should be matched down to the day. However this function will never return you someone younger than ${minimumAge} so it is probably not a huge deal

So my implementation looks something like this

generateRandonDateOfBirth
[Arguments] ${minimumAge}=13
${date}= Get Current Date
${currentTimeStamp}= Convert Date ${date} epoch exclude_millis=yes
${currentYear}= Convert Date ${date} result_format=%Y

${compareYear}= Convert To Integer ${currentYear}
${numberYears}= Convert To Integer ${minimumAge}
${compareYear}= Run Keyword Evaluate ${compareYear}-${numberYears}

${secsPerYear}= Set Variable 31557600
${subtractSeconds}= Run Keyword Evaluate ${minimumAge}*${secsPerYear}
${minAgeTimeStamp}= Run Keyword Evaluate ${currentTimeStamp}-${subtractSeconds}
${execStr}= Set Variable random.randint(1, ${minAgeTimeStamp})

:FOR ${i} IN RANGE 100
\ ${randDate}= Evaluate ${execStr} modules=random,sys
\ ${randomYear}= Convert Date ${randDate} result_format=%Y
\ Exit For Loop If ${compareYear} > ${randomYear}
${randYear}= Convert Date ${randDate} result_format=%Y
${randMonth}= Convert Date ${randDate} result_format=%m
${randDay}= Convert Date ${randDate} result_format=%d

[Return] ${randYear} ${randMonth} ${randDay}

So the first part converts minimum age into the oldest birth year that a random person can have.

The next section works out the maximum timestamp since epoch that a person could have. This is the upper bounds for the random number generator.

${execStr} is the string that gets Executed in the loop.

The loop is used to ensure that random person does exceed the age requirement.

Hope it is useful to people out there.