Formatting ActiveSupport::Duration Objects in Rails
rails activesupport helpers
Rails’ ActiveSupport::Duration objects don’t include a straightforward way to output clean, human-readable strings. By default, you’re left with #inspect, which is limited and lost locale support after Rails 5.1.
A Manual Helper
You could roll your own helper in a view:
def duration_as_sentence(duration)
parts = duration.parts
units = [:days, :hours, :minutes]
map = {
days: { one: :d },
hours: { one: :h, other: :hrs },
minutes: { one: :m, other: :mins }
}
parts.
sort_by { |unit, _| units.index(unit) }.
map { |unit, val| "#{val} #{val == 1 ? map[unit][:one] : map[unit][:other]}" }.
to_sentence
endThis works, but it’s limited, not very configurable, and ignores localization.
Introducing duration_in_words
To address this, I built a small gem called duration_in_words. It provides a view helper that formats ActiveSupport::Duration objects into concise, localized strings like:
include ActionView::Helpers::DurationHelper
>> duration = 2.hours
>> duration_in_words(duration)
=> "2h"
>> duration = 1.day + 2.hours + 30.minutes
>> duration_in_words(duration)
=> "1d 2h and 30m"Formatting Options
:format option
Two formats are supported: :compact (default) and :full.
de:
duration:
in_words:
format:
compact:
hours:
one: '%{count}Std.'
other: '%{count}Std.'
minutes:
one: '%{count}Min'
other: '%{count}Min'
seconds:
one: '%{count}s'
other: '%{count}s'
support:
words_connector: ' '
two_words_connector: ' und '
last_word_connector: ' und 'Usage:
duration = 1.day + 2.hours + 30.minutes
duration_in_words(duration, locale: :de)
# => "1T 2Std. und 30s"
duration_in_words(duration, format: :full, locale: :de)
# => "1 Tag, 2 Std., und 30 Sekunden"Wrap-up
When you need to report durations in a user-friendly way, duration_in_words provides a clean, configurable, and locale-aware solution. It’s a big improvement over the default #inspect output and saves you from reinventing formatting helpers.