我在请求示例应用程序的主页时收到以下错误消息(遵循Michael Hartl的教程第11章):
“页面#home中的ActiveRecord :: HasManyThroughSourceAssociationNotFoundError”
“无法在模型关系中找到源关联:followed_id。尝试'has_many:follows_users,:through =>:relationships,:source =>'。它是以下之一:follower或:follow?”
这真的很奇怪,因为我完全按照教程的说明进行操作。我甚至复制粘贴每个代码片段。
我的用户模型(摘录):
class User < ActiveRecord::Base
has_many :relationships, foreign_key: "follower_id", dependent: :destroy
has_many :followed_users, through: :relationships, source: "followed_id"
has_many :reverse_relationships, foreign_key: "followed_id", class_name: "Relationship", dependent: :destroy
has_many :followers, through: :reverse_relationships, source: :follower
我的关系模式:
class Relationship < ActiveRecord::Base
attr_accessible :followed_id
belongs_to :follower, class_name: "User"
belongs_to :followed, class_name: "User"
validates :follower_id, presence: true
validates :followed_id, presence: true
end
我的迁移文件:
class CreateRelationships < ActiveRecord::Migration
def change
create_table :relationships do |t|
t.integer :follower_id
t.integer :followed_id
t.timestamps
end
add_index :relationships, :follower_id
add_index :relationships, :followed_id
add_index :relationships, [:follower_id, :followed_id], unique: true
end
end
我一直在努力解决这个问题,但我根本不知道问题可能是什么(从教程中精确复制代码)。
答案 0 :(得分:17)
发现错误: 在我的用户模型中,我不得不改变
has_many :followed_users, through: :relationships, source: "followed_id"
到
has_many :followed_users, through: :relationships, source: :followed
在Hartl的教程清单11.10 http://ruby.railstutorial.org/book/ruby-on-rails-tutorial#code:has_many_following_through_relationships中似乎是一个错字,因为那时我得到的是“source:”follow_id“”代码。
我从Hartl的github“示例应用程序”获得了固定代码。