Question

如果我对自己的事情发表评论，我就不应该收到通知。我们如何删除这个＆＃34;功能＆＃34;？

class Comment < ActiveRecord::Base
  after_save :create_notification
  has_many :notifications
  has_many :comment_likes   
  has_many :likers, through: :comment_likes, class_name: 'User', source: :liker
  belongs_to :habit
  belongs_to :stat
  belongs_to :valuation
  belongs_to :goal
  belongs_to :user
  validates :user, presence: true
  default_scope { order('created_at') }

private

  def create_notification
    author = 
      if goal
        goal.user
      #elsif comment_like
      # comment_like.user
      elsif habit
       habit.user
      elsif stat
        stat.user
      elsif valuation
        valuation.user
      end
    notifications.create(
      comment:      self,
      likes:        likes,
      habit:        habit,
      stat:         stat,
      goal:         goal,
      valuation:    valuation,
      user:         author,      
      read:         false
    )
  end
end

可以对目标，估值，统计数据和＆amp;习惯。

class NotificationsController < ApplicationController
  before_action :correct_user, only: [:destroy]

  def index
    @notifications = current_user.notifications
    @notifications.each do |notification|
      notification.update_attribute(:read, true) 
    end
  end


    def destroy
      @notification = Notification.find(params[:id])
      @notification.destroy
      redirect_to :back
    end

private

  def correct_user
    @notification = current_user.notifications.find_by(id: params[:id])
    redirect_to root_url, notice: "Not authorized to edit this notification" if @notification.nil?
  end
end

CommentsController

class CommentsController < ApplicationController
  before_action :set_commentable, only: [:index, :new, :create]
  before_action :set_comment, only: [:edit, :update, :destroy]
  before_action :correct_user, only: [:edit, :update, :destroy]

  def index
    @comments = @commentable.comments
  end

  def new
    @comment = @commentable.comments.new
  end

  def create
    @comment = @commentable.comments.new(comment_params)
    if @comment.persisted?
      redirect_to @commentable, notice: "Comment created."
    else
      render :new
    end
  end

  def edit
  end

  def update
    if @comment.update_attributes(comment_params)
      redirect_to :back, notice: "Comment was updated."
    else
      render :edit
    end
  end

  def destroy
    @comment.destroy
    redirect_to @comment.commentable, notice: "Comment destroyed."
  end

  def like
    @comment = Comment.find(params[:id])
    @comment_like = current_user.comment_likes.build(comment: @comment)
    if @comment_like.save
      @comment.increment!(:likes)
      flash[:success] = 'Thanks for liking!'
    else
      flash[:error] = 'Too many likes'
    end  
    redirect_to(:back)
  end

  private

  def set_commentable
    @commentable = find_commentable
  end

  def set_comment
    @comment = current_user.comments.find(params[:id])
  end

  def correct_user
    @comment = current_user.comments.find_by(id: params[:id])
    redirect_to root_url, notice: "Not authorized to edit this comment" if @comment.nil?
  end

  def find_commentable
    if params[:goal_id]
      Goal.find(params[:goal_id])
    elsif params[:habit_id]
      Habit.find(params[:habit_id])
    elsif params[:valuation_id]
      Valuation.find(params[:valuation_id])
    elsif params[:stat_id]
      Stat.find(params[:stat_id])
    end
  end

  def comment_params
    params[:comment][:user_id] = current_user.id
    params.require(:comment).permit(:content, :commentable, :user_id, :like)
  end
end

如果您需要进一步的代码或解释，请与我们联系。长寿＆amp;繁荣：]

Answer 1

理想情况下，您不应该依赖回调。特别是如果像这种情况一样，你的回调必须访问在模型上下文之外不可用的数据。

解决方案很简单。而不是直接在控制器中创建调用ActiveRecord方法的注释，而是在注释本身中定义自定义方法。

class Comment
  # ...

  def self.create_comment(user, attributes)
    transaction do
        comment = new(attributes)
        if comment.save
            create_notification(user)
            # other after creation methods here
        end
        comment
    end
  end
end

现在create_notification可以访问当前用户。然后，在你的控制器中：

def create
  comment = Comment.create(current_user, params[:comments])
  if comment.persisted?
    # saved
  else
    # not saved
    # comment.errors
  end
end

有几种变化。您也可以始终使用实例。

class Comment
  # ...

  def create_comment(user, attributes)
    transaction do
        comment.attributes = attributes
        if result = comment.save
            create_notification(user)
            # other after creation methods here
        end
        result
    end
  end
end

def create
  comment = Comment.new
  if comment.create_comment(current_user, params[:comments])
    # saved
  else
    # not saved
    # comment.errors
  end
end

无论你的实现是什么，关键是回调不应该被滥用。特别是，它们应该用于保证同一模型内的一致性，并且您不应该开始在模型之间引入显式依赖关系，否则您的代码将很快变得缓慢且无法维护。

如果current_user如何发送通知？

1 个答案: