Getting “argument out of range” when trying to turn a duration into milliseconds in Rails 4

Question

I'm using Rails 4.2.4. I have the below method for converting a time (duration) to milliseconds …

Time.parse(convert_to_hrs(duration)).seconds_since_midnight * 1000

in which the method “convert_to_hrs” is defined as

    def convert_to_hrs(string)
      case string.count(':')
      when 0
        '00:00:' + string.rjust(2, '0')
      when 1
        '00:' + string
      else
        string
      end
    end

However, if the duration is something really big (eg “34:13:00” -- read: 34 hours, 13 minutes, and zero seconds), the above fails with the error

Error during processing: argument out of range
/Users/mikea/.rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/time.rb:302:in `local'
/Users/mikea/.rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/time.rb:302:in `make_time'
/Users/mikea/.rvm/rubies/ruby-2.3.0/lib/ruby/2.3.0/time.rb:366:in `parse'
/Users/mikea/Documents/workspace/myproject/app/services/my_service.rb:25:in `block in process_page_data'
/Users/mikea/Documents/workspace/myproject/app/services/my_service.rb:22:in `each'
/Users/mikea/Documents/workspace/myproject/app/services/my_service.rb:22:in `process_page_data'

How do I rewrite my first line to accurately convert duration into milliseconds?

Answer 1

Time.parse is throwing error, becuase values you passing in duration variable is out of range.

For Ex: Time.parse(convert_to_hrs('59:59')) as per your written code , it's return 2016-07-27 00:59:59 +0530

Here the value 59:59 consider as minutes:seconds , so if you pass the value 60:60 then it will raise the error argument out of range

Here is the official documentation for parse method of Time

Hope this will help you.

Answer 2

If you know you're always going to be using a hours:minutes:seconds format, but the number in each field isn't guaranteed to be inside the 'normal' range (eg 0-23 for hours, 0-59 for minutes, etc), then you're probably best off doing it 'manually' using something like this:

def duration_in_milliseconds(input)
  h, m, s = input.split(':').map(&:to_i)
  (h.hours + m.minutes + s.seconds) * 1000
end

puts duration_in_milliseconds('34:13:00') #=> 123180000

Note that this only works with ActiveSupport, but you have that, since you've specified Rails. Also, this assumes you're always getting all three terms (eg 5 seconds is 00:00:05). The full setup that accepts shorter strings as well would want to also use your convert_to_hrs method.

Note also that this works even if formatting isn't strictly 'time-like', as long as you have consistent colons as seperators:

puts duration_in_milliseconds('1:1:5') #=> 3665000

The Numeric#hours , Numeric#minutes and Numeric#seconds methods are provided by ActiveSupport, as part of active_support/core-ext/time.rb . They aren't particularly documented, but they return ActiveSupport::Duration objects, which have fancy methods for interacting with Time and Date issues like 5.days.ago , but when treated as an integer are effectively a number of seconds.