通过Rails在has_many上访问其他值 [英] Accessing additional values on has_many through Rails

问题描述

我真的很难通过has_many访问一个名为Permission的附加参数的值。这可能很简单。
我的3个模型是

I am having real trouble accessing the value of an additional parameter called permission on a has_many through. It is probably something simple. My 3 Models are

class User < ActiveRecord::Base
  has_many :players_users
  has_many :players, through: :players_users
end
class Player < ActiveRecord::Base
  has_many :players_users
  has_many :users, through: :players_users
end
class PlayersUser < ActiveRecord::Base
  belongs_to :user
  belongs_to :player
  validates :player_id, uniqueness: { scope: :user_id }
end

我的控制器保存记录而没有问题。将权限值添加到正确的联接表中。

My controller saves the record without issue. Adding the permission value to the correct joining table.

def create
    @players = Player.new(players_params)
    @user= current_user
    if @players.save
      @player = Player.last
      @user.save && @user.players_users.create(:player_id =>@player.id, :permission =>"owner")
      redirect_to '/players'
    else
      render 'new'
    end
  end

但是我似乎无法正确访问它
我尝试过

However I seem unable to access it properly I have tried

perm = User.find(current_user).players_users.includes(:Permission)
 if perm == "owner"

哪个给出了ActiveRecord :: AssociationNotFoundError，在PlayersUser上找不到名为 Permission的关联;也许您拼错了？

Which gives an ActiveRecord::AssociationNotFoundError, association named 'Permission' was not found on PlayersUser; perhaps you misspelled it?

我也尝试过

 perm = User.players_users.where(player_id = @player.id && user_id = current_user)
perm.permission

或

perm = User.Player.where(player_id = @player.id && user_id = current_user)

或

perm = User.players.where(player_id = @player.id && user_id = current_user)

哪个给出了未定义的方法错误。
未定义方法`Player'

Which gives an undefined method error. undefined method `Player'

我知道这在我的设置中很小，但无法弄清楚它是什么。

I know this is something small in my setup but cannot figure out what it is. Any help appreciated.

推荐答案

players_users 和玩家与User对象相关联，因此您可以将结果提取为

players_users and players are associated with User object, so you can fetch the results as,

current_user.players_users.pluck(:permission)

这篇关于通过Rails在has_many上访问其他值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！