ruby-on-rails - Rails 应用程序 : How to generate business hours in DB/Model and shows current status?

Question

在"How would you store a business's hours in the db/model of a Rails app" , Simon Franzen 提供 elegant solution (我是新手程序员，所以请注意这对我来说似乎是这样)。

我想知道如何在模型或 Controller 中实现 is_open? 方法来在 View 页面上反射(reflect)“业务已打开”或“业务已关闭”？

我不能直接问他，因为我没有足够的声誉点来评论他的解决方案。

Simon Franzen 的代码

架构:

# migration
class CreateOpeningHours < ActiveRecord::Migration
  def change
    create_table :opening_hours do |t|
      t.integer :entry_id # your model reference
      t.integer :day
      t.time :closes
      t.time :opens
      t.datetime :valid_from
      t.datetime :valid_through
    end
  end
end 

型号:

class OpeningHour < ActiveRecord::Base

  belongs_to :entry

  validates_presence_of :day, :closes, :opens, :entry_id
  validates_inclusion_of :day, :in => 1..7
  validate :opens_before_closes 
  validate :valid_from_before_valid_through 

  # sample validation for better user feedback
  validates_uniqueness_of :opens, scope: [:entry_id, :day]
  validates_uniqueness_of :closes, scope: [:entry_id, :day]

  protected
  def opens_before_closes
    errors.add(:closes, I18n.t('errors.opens_before_closes')) if opens && closes && opens >= closes
  end

  def valid_from_before_valid_through
    errors.add(:valid_through, I18n.t('errors.valid_from_before_valid_through')) if valid_from && valid_through && valid_from >= valid_through
  end

end

Answer 1

假设有一个模型 Business 存在，它 has_many :opening_hours 然后 open? (在 ruby​​ 中我们不需要过时的 is_ 前缀，因为我们可以在最后定义方法，用 ? 表示它返回 bool 值)方法可以实现如下:

class Business < ActiveRecord::Base
  has_many :opening_hours

  # ...

  def open?
    opening_hours.where("? BETWEEN opens AND closes", Time.zone.now).any?
  end

  # ...

end