DateRangeRollout

Gradual transition from one value to another between two dates.

Add this line to your application's Gemfile:

gem 'date_range_rollout'

And then execute:

$ bundle

Or install it yourself as:

$ gem install date_range_rollout

Example: Get the percentage of time elapsed in the year:

start_value = 0
start_date = Time.parse("2020-01-01")
end_value = 100
end_date = Time.parse("2020-12-31")

DateRangeRollout.build(start_value, start_date, end_value, end_date).get

Example: Slowly increase the numbers of jobs per day over the course of a month. Imagine this class being run every day. This will perform 100 (start_value) jobs until start_date, slowly increase the number until end_date, and stay at 500 (end_value) after that date. Since get returns a float, we want to round that value to the nearest integer.

class SomeWorker
  def perform
    start_value = 100
    start_date = Time.parse("2020-02-17")
    end_value = 500
    end_date = Time.parse("2020-03-17")

    jobs_count = DateRangeRollout.build(start_value, start_date, end_value, end_date).get

    jobs_count.round.times do
      JobClass.do_something
    end
  end
end

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/netlify/date_range_rollout.

The gem is available as open source under the terms of the MIT License.