识别 Rails 中的冲突约会是否适用于更新而不是创建？

Question

我编写了这个冲突方法来检查正在保存或创建的约会是否与已经为特定培训师保存的约会发生冲突。在有人尝试在def create 和def update 中创建或更新现有约会后，首先调用此方法。

它在更新约会时有效，但在创建时识别冲突。

有什么想法吗？

  def is_conflicting()
    @new_appointment = person.appointments.build(params[:appointment])
    @appointments = Appointment.all(:conditions => { :date_of_appointment => @new_appointment.date_of_appointment, :doctor_id => @new_appointment.doctor_id})
    @appointments.each do |appointment|
      logger.info( appointment)
        if(@new_appointment.start_time < appointment.end_time && appointment.start_time < @new_appointment.end_time)
          return true 
        end
    end
    return false
  end

def create
    @appointment = person.appointments.build(params[:appointment])
      respond_to do |format|
        if(is_conflicting == false)
        if @appointment.save
....more code...
        end
        end
      end 
end

  def update
    @appointment = person.appointments.find(params[:id])
      respond_to do |format|
        if(is_conflicting == false)
          if @appointment.update_attributes(params[:appointment])
        .....more code...........
           end
         end
     end
   end

设置医生的表格部分。

  <p>
    <%= f.label :doctor_id %>
    <%= f.select :doctor_id, Doctor.find(:all, :order => "name").collect { |s|
        [s.name, s.id]} %>
  </p>

谢谢你

Answer 1

你正在创造一个不可能的条件。你的条件说@new_appointment必须在appointment的end_time之后有一个start_time，在appointment的start_time之前有一个end_time......这在逻辑上是不可能的。

我建议使用这个： http://api.rubyonrails.org/classes/ActiveSupport/CoreExtensions/Range/Overlaps.html

您需要根据开始和结束时间创建范围，例如@new_appointment.start_time..@new_appointment.end_time

Answer 2

我认为您想要做的是将其下推至约会模型上的验证。见http://api.rubyonrails.org/classes/ActiveRecord/Validations.html#M001391。

在 appt_range 下面的 sn-p 中构建了一个从开始到结束时间的范围，并且应该在创建/更新时调用 validate 方法。

也许是这样的。

class Appointment < ActiveRecord::Base

  def appt_range
    start_time..end_time 
   end

   ...rest of code...
   protected
   def validate
     @appointments = Appointment.all(:conditions => { :date_of_appointment => date_of_appointment, :doctor_id => doctor_id})
     errors.add_to_base("Appointment Conflict") if @appointments.any? {|appt| appt.appt_range.overlaps? appt_range}
  end 
end

然后你的控制器就会有

 def create
 @appointment = person.appointments.new(params[:appointment]))
    if @appointment.save
       ...
    end
end 

def update
    @appointment = person.appointments.find(params[:id])
    if @appointment.update_attributes(params[:appointment])
    ...
    end
end

但是话虽如此（这也是您原始代码中的问题），但存在竞争条件/问题。假设患者有一个从 10:00 -> 10:30 开始的 appt，并且他们想将其移至 10:15->10:45。由于当时已经为患者预约了医生，因此更新将失败。也许添加 patient_id 而不是当前患者可以解决这种极端情况，但您的测试应该涵盖这种可能性。

另外，我只是把它从脑海中浮现出来，还没有测试过，所以你的里程可能会有所不同（你没有指定 rails 的版本，但是从代码来看。看起来是 2.3.x？）。但希望这能为您指明更好的方向..

编辑...

我构建了一个准系统/简单的 rails 2.3.8 应用程序来测试它，它似乎可以在 create 上运行。看看http://github.com/doon/appt_test 我也包含了开发数据库。

 rake db:migrate                                                                                                                                                  
==  CreateAppointments: migrating =============================================
-- create_table(:appointments)
   -> 0.0019s
==  CreateAppointments: migrated (0.0020s) ====================================

Loading development environment (Rails 2.3.8)
ruby-1.8.7-p299 > a=Appointment.new(:patient_id=>1, :doctor_id=>1, :date_of_appointment=>'08/10/2010', :start_time=>" 2010-08-10 8:00", :end_time=>"2010-08-10 10:00")
 => #<Appointment id: nil, patient_id: 1, doctor_id: 1, date_of_appointment: "2010-08-10", start_time: "2000-01-01 08:00:00", end_time: "2000-01-01 10:00:00", created_at: nil, updated_at: nil> 
ruby-1.8.7-p299 > a.save
  Appointment Load (0.2ms)   SELECT * FROM "appointments" WHERE ("appointments"."doctor_id" = 1 AND "appointments"."date_of_appointment" = '2010-08-10') 
  Appointment Create (0.5ms)   INSERT INTO "appointments" ("end_time", "created_at", "updated_at", "patient_id", "doctor_id", "date_of_appointment", "start_time") VALUES('2000-01-01 10:00:00', '2010-08-07 22:20:33', '2010-08-07 22:20:33', 1, 1, '2010-08-10', '2000-01-01 08:00:00')
 => true 
ruby-1.8.7-p299 > b=Appointment.new(:patient_id=>1, :doctor_id=>1, :date_of_appointment=>'08/10/2010', :start_time=>" 2010-08-10 9:00", :end_time=>"2010-08-10 11:00")
 => #<Appointment id: nil, patient_id: 1, doctor_id: 1, date_of_appointment: "2010-08-10", start_time: "2000-01-01 09:00:00", end_time: "2000-01-01 11:00:00", created_at: nil, updated_at: nil> 
ruby-1.8.7-p299 > b.save
  Appointment Load (0.4ms)   SELECT * FROM "appointments" WHERE ("appointments"."doctor_id" = 1 AND "appointments"."date_of_appointment" = '2010-08-10') 
 => false 
ruby-1.8.7-p299 > b.errors['base']
 => "Appointment Conflict" 
ruby-1.8.7-p299 > c=Appointment.new(:patient_id=>1, :doctor_id=>1, :date_of_appointment=>'08/10/2010', :start_time=>" 2010-08-10 11:00", :end_time=>"2010-08-10 12:00")
 => #<Appointment id: nil, patient_id: 1, doctor_id: 1, date_of_appointment: "2010-08-10", start_time: "2000-01-01 11:00:00", end_time: "2000-01-01 12:00:00", created_at: nil, updated_at: nil> 
ruby-1.8.7-p299 > c.save
  Appointment Load (0.3ms)   SELECT * FROM "appointments" WHERE ("appointments"."doctor_id" = 1 AND "appointments"."date_of_appointment" = '2010-08-10') 
  Appointment Create (0.4ms)   INSERT INTO "appointments" ("end_time", "created_at", "updated_at", "patient_id", "doctor_id", "date_of_appointment", "start_time") VALUES('2000-01-01 12:00:00', '2010-08-07 22:21:39', '2010-08-07 22:21:39', 1, 1, '2010-08-10', '2000-01-01 11:00:00')
 => true 

这是我的 Appointment 类（我使用了 validate :symbol 方法）

class Appointment < ActiveRecord::Base

  validate :conflicting_appts

  def appt_range
    start_time..end_time 
  end


  private
  def conflicting_appts
    @appointments = Appointment.all(:conditions => { :date_of_appointment => date_of_appointment, :doctor_id => doctor_id})
    errors.add_to_base("Appointment Conflict") if @appointments.any? {|appt| appt.appt_range.overlaps? appt_range}
  end
end

同样在玩这个，虽然你应该确保测试另一种情况。患者 A 在 10 至 11 日与 A 医生有约会。患者 B 从 11 到 12 日与 Dr a 进行了约会。这些将在当前实现中重叠，因为它们共享 11 个共同点，并将被标记为冲突。

所以我不确定为什么它在创建时不起作用，如果您想显示您的代码，我们可以查看它。

好的，我知道它为什么不起作用了，这与开始时间和结束时间有关。看看这个。

来自测试...（在验证中添加一个记录器向我展示了这一点）。

appt.range == Sat Jan 01 09:06:00 UTC 2000..Sat Jan 01 21:10:00 UTC 2000 , my range = Tue Aug 10 09:15:00 UTC 2010..Tue Aug 10 14:19:00 UTC 2010
appt.range == Sat Jan 01 22:06:00 UTC 2000..Sat Jan 01 23:06:00 UTC 2000 , my range = Tue Aug 10 09:15:00 UTC 2010..Tue Aug 10 14:19:00 UTC 2010
appt.range == Sat Jan 01 09:30:00 UTC 2000..Sat Jan 01 12:14:00 UTC 2000 , my range = Tue Aug 10 09:15:00 UTC 2010..Tue Aug 10 14:19:00 UTC 2010
appt.range == Sat Jan 01 09:31:00 UTC 2000..Sat Jan 01 12:20:00 UTC 2000 , my range = Tue Aug 10 09:15:00 UTC 2010..Tue Aug 10 14:19:00 UTC 2010

当您从数据库中提取日期部分时，日期部分被截断并设置为 2000 年 1 月 1 日。因此，当您查询数据库时，您正在查看的范围不会重叠对于 2010 年的日期。将开始/结束时间设为日期时间将解决问题，因为这样日期将再次重要。否则需要修改 appt_range 以将日期调整回 date_of_appointment。更新时不会发生这种情况，因为您正在处理数据库中的所有数据。所以一切都有相同的日期

见http://github.com/doon/EMR/commit/b453bb3e70b5b6064bb8693cf3986cf2219fbad5

def appt_range
   s=Time.local(date_of_appointment.year, date_of_appointment.month, date_of_appointment.day, start_time.hour, start_time.min, start_time.sec)
   e=Time.local(date_of_appointment.year, date_of_appointment.month, date_of_appointment.day, end_time.hour, end_time.min, end_time.sec)
  s..e
end

通过强制开始和结束时间使用 date_of_appointment 来修复它...

Answer 3

build 仅对已保存在数据库中的对象进行操作：请参见此处：http://apidock.com/rails/ActiveRecord/Associations/ClassMethods 在这里Ruby on Rails. How do I use the Active Record .build method in a :belongs to relationship?

此外，您的代码仍然可以使用一些重构。您的 if 语句将返回 true 或 false，那么您为什么还要费心专门返回 true。此外，您不需要空括号，您应该将返回布尔值的方法定义为以问号结尾。最后，为什么要在 create 方法中创建一个新的约会，然后在验证方法中创建一个新对象？

def conflicting? appointment
  @appointments = Appointment.all(:conditions => {... all of them})
  # Enumerable#any? returns true or false for the collection, 
  # so you dont have to specify a return value 
  # since its the last evaluation in the method
  @appointments.any?{|apt| appointment.start_time < apt.end_time && apt.start_time < appointment.end_time} #=> takes each appointment in appointments assigns to apt and checks against the passed in appointment object
end

然后在您的创建或更新方法中

# assuming start/end times are form parameters coming from a view
@appointment = Appointment.new params[:appointment]
# substituting the lookup and update_attributes in the update action, obviously
@appointment.save unless conflicting? @appointment

Answer 4

其中的 if else 语句的数量令人不快。我说不清这是什么逻辑。尝试使用可枚举类进行此类工作。您可能只是在嵌套中出现错误。我发现return true 经常会产生不良结果，例如即使您认为逻辑可靠，也总是返回 true。

jruby-1.5.0 > apt1 = (1.hour.from_now..2.hour.from_now) #=> Fri, 06 Aug 2010 01:58:43 UTC +00:00..Fri, 06 Aug 2010 02:58:43 UTC +00:00 

jruby-1.5.0 > apt2 = (3.hour.from_now..4.hour.from_now)#=> Fri, 06 Aug 2010 03:59:07 UTC +00:00..Fri, 06 Aug 2010 04:59:07 UTC +00:00 

jruby-1.5.0 > @appointments = [apt1, apt2]

jruby-1.5.0 > @appointments.any?{|apt| (5.hour.from_now..6.hour.from_now).overlaps? apt } #=> false 

jruby-1.5.0 > @appointments.any?{|apt| (1.hour.from_now..3.hour.from_now).overlaps? apt } #=> true