Eventos recorrentes no ruby on rails. A criação recorrência de eventos em qualquer ambiente, requer uma avançada lógica de regras. Entre as dificuldades está os Time Zones, UTC e o querido mês de Fevereiro. Pra facilitar tudo isso, existe uma gem chamada Ice Cube. Que irá ajudar a criar uma regra de repetição para um evento. Fonte: http://seejoh…

_recurrence.html.haml

%fieldset.recurrences
  %legend Recurrences
  .row-fluid
    .span2
      = f.input :period_type, input_html: {class: ""}, collection: Dieting::RECURRING_RULES, label_method: :last, value_method: :first, as: :radio_buttons, item_wrapper_class: 'inline btn span12'
    .span10.week_days
      .row-fluid
        = f.input :day, input_html: {class: ""}, label_html: {class: "days-checkbox"}, collection: Dieting::WEEK_DAYS, label_method: :last, value_method: :first, as: :check_boxes, item_wrapper_class: 'inline btn span3'
    .span10.month_days
      .row-fluid
        = f.input :day_of_month, input_html: {class: ""}, label_html: {class: "days-checkbox"}, collection: Dieting::MONTH_DAYS, label_method: :last, value_method: :first, as: :check_boxes, item_wrapper_class: 'inline btn month'

dieting.rb

class Dieting < ActiveRecord::Base
  include IceCube
  attr_accessible :period_type, :recurring_rule, :day, :day_of_month
  attr_accessor :period_type, :recurring_rule, :day, :day_of_month
  serialize :recurring_rule, Hash

  RECURRING_RULES = [[IceCube::Rule.weekly,"Weekly"],[IceCube::Rule.monthly,"Monthly"]]
  WEEK_DAYS = {1 => "Monday", 2 => "Tuesday", 3 => "Wednesday", 4 => "Thursday", 5 => "Friday", 6 => "Saturday", 7 => "Sunday"}
  MONTH_DAYS = {}
  (1..31).to_a.each do |m_day|
    MONTH_DAYS[m_day] = m_day.to_s
  end

  def recurring_rule=(new_schedule)
    write_attribute(:recurring_rule, new_schedule.to_hash)
  end

  def recurring_rule
    Schedule.from_hash(read_attribute(:recurring_rule))
  end

  def day
    rule_is_present? ? self.recurring_rule.to_hash[:rrules].first()[:validations][:day] : nil
  end

  def day_of_month
    rule_is_present? ? self.recurring_rule.to_hash[:rrules].first()[:validations][:day_of_month] : nil
  end

  def period_type
    rule_is_present? ? self.recurring_rule.to_hash[:rrules].first[:rule_type].match(/::([\w]+)Rule/)[1] : nil
  end

  private
    def rule_is_present?
      self.recurring_rule.to_hash[:rrules].present?
    end
end

dietings_controller.rb

class DietingsController < ApplicationController
  def create
    @dieting = Dieting.new(params[:dieting])
    create_schedule params, @dieting

    respond_to do |format|
      if @dieting.save
        format.html { redirect_to @dieting, notice: 'Dieting was successfully created.' }
        format.json { render json: @dieting, status: :created, location: @dieting }
      else
        format.html { render action: "new" }
        format.json { render json: @dieting.errors, status: :unprocessable_entity }
      end
    end
  end

  def update
    @dieting = Dieting.find(params[:id])
    create_schedule params, @dieting

    respond_to do |format|
      if @dieting.update_attributes(params[:dieting])
        format.html { redirect_to @dieting, notice: 'Dieting was successfully updated.' }
        format.json { head :no_content }
      else
        format.html { render action: "edit" }
        format.json { render json: @dieting.errors, status: :unprocessable_entity }
      end
    end
  end

  private
    def create_schedule params, dieting
      day_rules = {weekly: "day", monthly: "day_of_month"}

      schedule = IceCube::Schedule.new(dieting.start, end_date: dieting.end)
      period_type = params[:dieting][:period_type].downcase
      day_rule = day_rules.with_indifferent_access[period_type]

      days = params[:dieting][day_rules.with_indifferent_access[period_type]].reject { |c| c.empty? }
      schedule.add_recurrence_rule IceCube::Rule.send(period_type).send(day_rule, days.map(&:to_i)).until(dieting.end)

      @dieting.recurring_rule = schedule
    end
end

Gemfile

gem 'ice_cube'