ice_cube - Easy schedule expansion

gem install ice_cube

ice_cube is a ruby library for easily handling repeated events (schedules). The API is modeled after [iCalendar events][ical-3.6.1], in a pleasant Ruby syntax. The power lies in the ability to specify multiple rules, and have ice_cube quickly figure out whether the schedule falls on a certain date (.occurs_on?), or what times it occurs at (.occurrences, .first, .all_occurrences).

Imagine you want:

Every friday the 13th that falls in October

You would write:

schedule = IceCube::Schedule.new
schedule.add_recurrence_rule(
  IceCube::Rule.yearly.day_of_month(13).day(:friday).month_of_year(:october)
)

list occurrences until end_time (end_time is needed for non-terminating rules)

occurrences = schedule.occurrences(end_time) # [now]

or all of the occurrences (only for terminating schedules)

occurrences = schedule.all_occurrences # [now, now + 2.days, now + 3.days]

or check just a single time

schedule.occurs_at?(now + 1.day) # false schedule.occurs_at?(now + 2.days) # true

or check just a single day

schedule.occurs_on?(Date.today) # true

or check whether it occurs between two dates

schedule.occurs_between?(now, now + 30.days) # true schedule.occurs_between?(now + 4.days, now + 30.days) # false

or the first (n) occurrences

schedule.first(2) # [now, now + 2.days] schedule.first # now

or the last (n) occurrences (if the schedule terminates)

schedule.last(2) # [now + 2.days, now + 3.days] schedule.last # now + 3.days

or the next occurrence

schedule.next_occurrence(from_time) # defaults to Time.now schedule.next_occurrences(4, from_time) # defaults to Time.now schedule.remaining_occurrences # for terminating schedules

or the previous occurrence

schedule.previous_occurrence(from_time) schedule.previous_occurrences(4, from_time)

or include prior occurrences with a duration overlapping from_time

schedule.next_occurrences(4, from_time, spans: true) schedule.occurrences_between(from_time, to_time, spans: true)

or give the schedule a duration and ask if occurring_at?

schedule = IceCube::Schedule.new(now, duration: 3600) schedule.add_recurrence_rule IceCube::Rule.daily schedule.occurring_at?(now + 1800) # true schedule.occurring_between?(t1, t2)

using end_time also sets the duration

schedule = IceCube::Schedule.new(start = Time.now, end_time: start + 3600) schedule.add_recurrence_rule IceCube::Rule.daily schedule.occurring_at?(start + 3599) # true schedule.occurring_at?(start + 3600) # false

take control and use iteration

schedule = IceCube::Schedule.new schedule.add_recurrence_rule IceCube::Rule.daily.until(Date.today + 30) schedule.each_occurrence { |t| puts t }


The reason that schedules have durations and not individual rules, is to
maintain compatibility with the ical
RFC: http://www.kanzaki.com/docs/ical/rrule.html

To limit schedules use `count` or `until` on the recurrence rules. Setting `end_time` on the schedule just sets the duration (from the start time) for each occurrence.

---

## Using your words

ice_cube can provide ical or string representations of individual rules, or the
whole schedule.

```ruby
rule = IceCube::Rule.daily(2).day_of_week(tuesday: [1, -1], wednesday: [2])

rule.to_ical # 'FREQ=DAILY;INTERVAL=2;BYDAY=1TU,-1TU,2WE'

rule.to_s # 'Every 2 days on the last and 1st Tuesdays and the 2nd Wednesday'

Some types of Rules

There are many types of recurrence rules that can be added to a schedule:

Daily

# every day
schedule.add_recurrence_rule IceCube::Rule.daily

# every third day
schedule.add_recurrence_rule IceCube::Rule.daily(3)

Weekly

# every week
schedule.add_recurrence_rule IceCube::Rule.weekly

# every other week on monday and tuesday
schedule.add_recurrence_rule IceCube::Rule.weekly(2).day(:monday, :tuesday)

# for programmatic convenience (same as above)
schedule.add_recurrence_rule IceCube::Rule.weekly(2).day(1, 2)

# specifying a weekly interval with a different first weekday (defaults to Sunday)
schedule.add_recurrence_rule IceCube::Rule.weekly(1, :monday)

Monthly (by day of month)

# every month on the first and last days of the month
schedule.add_recurrence_rule IceCube::Rule.monthly.day_of_month(1, -1)

# every other month on the 15th of the month
schedule.add_recurrence_rule IceCube::Rule.monthly(2).day_of_month(15)

Monthly rules will skip months that are too short for the specified day of month (e.g. no occurrences in February for day_of_month(31)).

Monthly (by day of Nth week)

# every month on the first and last tuesdays of the month
schedule.add_recurrence_rule IceCube::Rule.monthly.day_of_week(tuesday: [1, -1])

# every other month on the first monday and last tuesday
schedule.add_recurrence_rule IceCube::Rule.monthly(2).day_of_week(
  monday: [1],
  tuesday: [-1]
)

# for programmatic convenience (same as above)
schedule.add_recurrence_rule IceCube::Rule.monthly(2).day_of_week(1 => [1], 2 => [-1])

Yearly (by day of year)

# every year on the 100th days from the beginning and end of the year
schedule.add_recurrence_rule IceCube::Rule.yearly.day_of_year(100, -100)

# every fourth year on new year's eve
schedule.add_recurrence_rule IceCube::Rule.yearly(4).day_of_year(-1)

Yearly (by month of year)

# every year on the same day as start_time but in january and february
schedule.add_recurrence_rule IceCube::Rule.yearly.month_of_year(:january, :february)

# every third year in march
schedule.add_recurrence_rule IceCube::Rule.yearly(3).month_of_year(:march)

# for programmatic convenience (same as above)
schedule.add_recurrence_rule IceCube::Rule.yearly(3).month_of_year(3)

Hourly (by hour of day)

# every hour on the same minute and second as start date
schedule.add_recurrence_rule IceCube::Rule.hourly

# every other hour, on mondays
schedule.add_recurrence_rule IceCube::Rule.hourly(2).day(:monday)

Minutely (every N minutes)

# every 10 minutes
schedule.add_recurrence_rule IceCube::Rule.minutely(10)

# every hour and a half, on the last tuesday of the month
schedule.add_recurrence_rule IceCube::Rule.minutely(90).day_of_week(tuesday: [-1])

Secondly (every N seconds)

# every second
schedule.add_recurrence_rule IceCube::Rule.secondly

# every 15 seconds between 12:00 - 12:59
schedule.add_recurrence_rule IceCube::Rule.secondly(15).hour_of_day(12)

recurring_select

The team over at GetJobber have open-sourced RecurringSelect, which makes working with IceCube easier in a Rails app via some nice helpers.

Check it out at https://github.com/GetJobber/recurring_select

Contributors

https://github.com/seejohnrun/ice_cube/graphs/contributors

Issues?

Use the GitHub [issue tracker][ice_cube-issues]

ice_cube