Accessing rails flash[:notice] in a model

问题

I am trying to assign a message to flash[:notice] in a model observer.

This question has already been asked: Ruby on Rails: Observers and flash[:notice] messages?

However, I get the following error message when I try to access it in my model:

undefined local variable or method `flash' for #<ModelObserver:0x2c1742c>

Here is my code:

class ModelObserver < ActiveRecord::Observer
  observe A, B, C

  def after_save(model)
    puts "Model saved"
    flash[:notice] = "Model saved"
  end
end

I know the method is being called because "Model saved" is printed to the terminal.

Is it possible to access the flash inside an observer, and if so, how?

回答1:

I needed to set flash[:notice] in the model to override the generic "@model was successfuly updated".

This what I did

Created a virtual attribute in the respective model called flash_notice
Then I set the virtual attribute in the respective model when needed
Used an after_filter when this virtual attribute was not blank to override the default flash

You can see my controller and model how I accomplished this below:

class Reservation < ActiveRecord::Base

  belongs_to :retailer
  belongs_to :sharedorder
  accepts_nested_attributes_for :sharedorder
  accepts_nested_attributes_for :retailer

  attr_accessor :validation_code, :flash_notice

  validate :first_reservation, :if => :new_record_and_unvalidated

  def new_record_and_unvalidated
    if !self.new_record? && !self.retailer.validated?
      true
    else
      false
    end
  end

  def first_reservation
    if self.validation_code != "test" || self.validation_code.blank?
      errors.add_to_base("Validation code was incorrect") 
    else
      self.retailer.update_attribute(:validated, true)
      self.flash_notice = "Your validation as successful and you will not need to do that again"
    end
  end
end

class ReservationsController < ApplicationController

  before_filter :authenticate_retailer!
  after_filter :flash_notice, :except => :index

  def flash_notice
    if !@reservation.flash_notice.blank?
      flash[:notice] = @reservation.flash_notice
    end
  end
end

回答2:

No, you set it in the controller where the saving is occurring. flash is a method defined on ActionController::Base.

来源：https://stackoverflow.com/questions/2701932/accessing-rails-flashnotice-in-a-model

标签

ruby-on-rails

activerecord

rails-flash