使用有很多通过rails 5来保存记录

Question

我无法找到无法将记录保存到数据库中的原因...帮助我找到我在模型和控制器中出错的原因。

User.rb

has_many :interested_users_lists
has_many :interested_posts, through: :interested_users_lists
accepts_nested_attributes_for :interested_users_lists, :interested_posts

...等

InterestedUsersList.rb

class InterestedUsersList < ApplicationRecord
    # belongs_to :post
    # belongs_to :users 
    belongs_to :interested_post, class_name: 'Post'    
    belongs_to :interested_user, class_name: 'User' 
end

Post.rb

belongs_to :owner, :class_name => "User", :foreign_key => "user_id", touch: true
has_many :interested_users_lists, dependent: :destroy
has_many :interested_users, through: :interested_users_lists
accepts_nested_attributes_for :interested_users_lists, :interested_users

...等 我使用的方法：

  # add interested user
  def add_interested_user(user)
   puts "this is user id:  #{user.id} "
   interestedUser = self.interested_users_lists.build(user_id: user.id)
   interestedUser.save
   puts "this is #{interested_users_lists.first.user_id} "
  end

迁移文件

class CreateInterestedUsersLists < ActiveRecord::Migration[5.0]
  def change
    create_table :interested_users_lists do |t|
      t.integer :user_id
      t.integer :post_id

      t.timestamps
    end
  end
end

posts_controller.rb

def interested
 @post.add_interested_user(current_user) #cannot be saved...
end
...
private
 def post_params
  params.require(:post).permit(:subject, :price, :category, :street_address, :city, :state, :zip, :condition, :payment_method, :content, post_attachments_attributes: [:id, :post_id, :avatar], 
                                interested_users_lists_attributes: [:id, :post_id, :user_id])
end

开发日志

  Post Load (0.1ms)  SELECT  "posts".* FROM "posts" WHERE "posts"."id" = ? ORDER BY "posts"."created_at" DESC LIMIT ?  [["id", 1], ["LIMIT", 1]]
this is user id:  2

   **(0.0ms)  begin transaction
   (0.1ms)  rollback transaction** _why???_

  InterestedUsersList Load (0.1ms)  SELECT "interested_users_lists".* FROM "interested_users_lists" WHERE "interested_users_lists"."post_id" = ?  [["post_id", 1]]
this is 2
Redirected to http://localhost:3000/users/posts/2
Completed 302 Found in 77ms (ActiveRecord: 4.9ms)


Started GET "/users/posts/2" for ::1 at 2016-12-27 03:04:33 -0800

Answer 1

更改此方法您不需要保存直通记录

# add interested user
def add_interested_user(user)
  self.interested_users << user
end