ruby-on-rails - rails : Adding to errors[:base] does not make record invalid?

Question

在我的 Purchase模型，我有一种计算税收的方法:

def calculate_tax
  if self.shipping_address.state == State.new_york
    corresponding_tax = Tax.find_by(zip_code: self.shipping_address.zip_code, state_id: self.shipping_address.state_id)
    if corresponding_tax
      self.tax = corresponding_tax.rate * (self.subtotal + shipping)
    else
      #HERE !!!
      self.errors[:base] << "The zip code you have entered is invalid."
      puts "errors = #{self.errors.full_messages}" #<-- this prints out the error in my log, so I know it's being run
    end
  else
    self.tax = 0.00
  end
end

在此方法中调用此方法:

def update_all_fees!
  calculate_subtotal
  calculate_shipping
  calculate_tax #<-- being called here
  calculate_total
  save!
end

然而， save!正在成功保存记录。不应该抛出异常吗？我怎么做才能省!当calculate_tax 在第二个 else 时失败堵塞？

Answer 1

您可以使用 validate 添加自定义验证方法。指示。以下可能采用您发布的代码:

class Purchase < ActiveRecord::Base
  validate :new_york_needs_tax_record

  def update_all_fees!
    calculate_subtotal
    calculate_shipping
    calculate_tax
    calculate_total
    save!
  end

  private

  def calculate_tax
    if ships_to_new_york? && corresponding_tax
      self.tax = corresponding_tax.rate * (self.subtotal + shipping)
    elsif !ships_to_new_york?
      self.tax = 0.00
    else
      self.tax = nil
    end
  end

  def ships_to_new_york?
    self.shipping_address.state == State.new_york
  end

  def corresponding_tax
    Tax.find_by(zip_code: self.shipping_address.zip_code, state_id: self.shipping_address.state_id)
  end

  def new_york_need_tax_record
    if ships_to_new_york?  && !corresponding_tax
      self.errors[:base] << "The zip code you have entered is invalid."
    end
  end
end