Question

ruby 1.9.2p290
rails 3.1.1

我有这些模特：

class Recipe < ActiveRecord::Base
 belongs_to :festivity 
end

class Festivity < ActiveRecord::Base
 has_many :recipes 
end

我在“食谱”表中有以下字段：

festivity_id

“庆祝活动”表格中的以下日期时间字段：

starts_at
ends_at

如何根据庆祝日期显示内容？

我开始以这种静态方式思考：

class PagesController < ApplicationController
 def home
  @recipes_by_festivities = Recipe.where(:festivity_id => 4).all(:order => 'RAND()', :limit => 8)
 end
end

例如：在Xmas期间（约12月份），我想显示一个festivity_id = 1的食谱列表。在感恩节期间，我想要一个festivity_id = 4的食谱列表。

我清楚了吗？如果我没有，请告诉我。

解

@current_festivity = Festivity.find(:last, :conditions => ["? between starts_at AND ends_at", Time.utc(0,Time.now.month,Time.now.day,0,0,0)])

@recipes_by_festivities = Recipe.where(:festivity_id => @current_festivity).all(:order => 'RAND()', :limit => 8)

Answer 1

我要做的是在庆祝活动表格中创建一个“名称”字段，然后使用holidays gem确定特定日期是否有假期。

Holdays.on(Date.today)

将返回哈希列表：每个哈希都有一个名称密钥。然后你可以使用它来查找正确的Festivity对象current_festival = Festivies.where(:name => Holdays.on(Date.today)[0][:name])并从那里获得食谱：current_festival.recipes

Answer 2

由于您希望通过庆祝活动找到食谱，您可以这样做：

def home
  festivity_today = some_custom_festivity_lookup(Time.now)
  if !festivity_today.nil?
    @recipes = Recipe.where(festivity_id: festivity_today.id).limit(8)
  else
    @recipes = Recipe.limit(8)
  end
end

Answer 3

这假定starts_at和ends_at保存在同一年（0），除非期间是两年中（例如圣诞节时间）：在这种情况下， ends_at年必须为1。

Festivity.create(name: 'Christmas time', starts_at: Time.utc(0,12,25,0,0,0), ends_at: Time.utc(1,1,6,23,59,59))
Festivity.create(name: 'Ferragosto', starts_at: Time.utc(0,8,15,0,0,0), ends_at: Time.utc(0,8,15,23,59,59))

Recipe.create(festivity: Festivity.find_by_name('Periodo natalizio'))
Recipe.create(festivity: Festivity.find_by_name('Ferragosto'))

# Searching for festivities today
Recipe.includes(:festivity).where(['? BETWEEN festivities.starts_at AND festivities.ends_at', Time.utc(0,Time.now.month,Time.now.day,12,0,0)]).all
# Searching for festivities on 15 August (in Italy there is a festivity that is called Ferragosto)
Recipe.includes(:festivity).where(['? BETWEEN festivities.starts_at AND festivities.ends_at', Time.utc(0,8,15,12,0,0)]).all
# Searching for festivities on 28 December
Recipe.includes(:festivity).where(['? BETWEEN festivities.starts_at AND festivities.ends_at', Time.utc(0,12,28,12,0,0)]).all

这是一个函数的可能实现：

def recipes_on(day, month)
  Recipe.includes(:festivity).where(['? BETWEEN festivities.starts_at AND festivities.ends_at', Time.utc(0,month,day,12,0,0)]).all
end

根据假期显示内容

3 个答案: