How do you convert an ISO 8601 date to a UNIX timestamp in Ruby?

Question

I've been trying Time.parse() and Date.parse(), but can't see to figure it out.

I need to convert a date in the form "2007-12-31 23:59:59" to a UNIX timestamp. Something like PHP's strtotime() function would be perfect.

Answer 1

The ISO 8601 time format for the example you give would be "2007-12-31T23:59:59", not "2007-12-31 23:59:59" (note the T between the data and time components).

In Ruby, if you require the time library, you can parse properly formatted ISO 8601 dates. If your dates are coming in with a space instead of a T to separate the date from the time, just replace it before passing it in to Time.iso8601:

>> require 'time'
=> true
>> Time.iso8601("2007-12-31 23:59:59".sub(/ /,'T'))
=> Mon Dec 31 23:59:59 -0500 2007

To convert a time in this format to a Unix timestamp, just use .to_i:

>> Time.iso8601("2007-12-31 23:59:59".sub(/ /,'T')).to_i
=> 1199163599

If you need more flexibility about the format, Time.parse should do the trick; I would be careful about using that in production code, however, because it might give unexpected values for malformed or invalid input, instead of throwing an exception.

Answer 2

You have Time.strptime in Ruby 1.9 So in your case,

>> time = Time.strptime('2007-12-31 23:59:59', '%Y-%m-%d %H:%M:%S')     
=> 2007-12-31 23:59:59 +0000

Once you have a Time object, you can convert it to many formats. A simple time.to_i will give you a Unix Timestamp.