Later is a lean Redis-backed event scheduling library for Ruby.
Later allows you to set unique events on a schedule and run them in the future:
require 'later' schedule = Later[:schedule] schedule.set 'event-1', Time.now + 60 schedule.set 'event-2', Time.now + 120 schedule.set 'event-3', Time.now + 180
Rescheduling an event is simple:
schedule.set 'event-1', Time.now + 240
And an event can unset with equal ease:
You can manage multiple schedules using different keys:
reservations = Later[:reservations] appointments = Later[:appointments]
The schedules are stored on the default Redis instance. If you need a schedule which must reside on a different Redis instance, you can pass a Nest object when referencing a schedule set.
redis = Redis.new host: host, port: port key = Nest.new 'Reservations', redis reservations = Later[key]
Workers are Ruby processes that run forever. They allow you to process event schedules in the background:
require 'later' Later[:schedule].each do |event| # Do something with the event. end # This line is never reached.
Later::Schedule#each accepts an optional
timeout parameter, which has a default value of
1. Passing an
Integer will use Redis' blocking mechanism
to process the schedule and is therefore more efficient. Passing a
Float will poll Redis using the given timeout, and should
only be used for events which need to be triggered with millisecond precision.
The below schedule will be polled every 0.1 seconds:
Later[:schedule].each(0.1) do |event| # Do something with the event. end
If for some reason, a worker has to stop itself from running:
Later[:schedule].each do |event| # Do something with the event. Later[:schedule].stop! if stop? end # This line is reached when stop? is true and Later[:reservations].stop! is called.
Add this line to your application's Gemfile:
And then execute:
Or install it yourself as:
$ gem install later
git checkout -b my-new-feature)
git commit -am 'Added some feature')
git push origin my-new-feature)