Rails 我的关系有问题

Question

我想要一个模型 Game 有两个用户：user1 和 user2

这是我的两个模型及其迁移：

game.rb:

class Game < ApplicationRecord

has_secure_token

# @!group RELATIONS
has_many :turns, dependent: :destroy
has_many :play_cards, dependent: :destroy
has_one :user1, class_name: 'User', dependent: :destroy
has_one :user2, class_name: 'User', dependent: :destroy
# @!endgroup

# @!group VALIDATORS
validates :user1_id, presence: true, blank: false, nill: false
validates :user2_id, presence: true, blank: false, nill: false
validates :finish_at, presence: true, blank: false, nill: false
validates :token, presence: true, blank: false, nill: false, length: { is: 24 }
# @!endgroup

end

迁移：

def change
create_table :games do |t|
  t.references :user1, foreign_key: { to_table: :users }
  t.references :user2, foreign_key: { to_table: :users }
  t.string :token, length: { is: 24 }, null: false
  t.datetime :finish_at, null: false

  t.timestamps
end
end

user.rb:

class User < ApplicationRecord

has_secure_token :token

# @!group RELATIONS
has_many :decks, dependent: :destroy
has_one :chosen_deck, class_name: 'Deck', dependent: :destroy
has_many :turns, dependent: :destroy
# @!endgroup

# @!group VALIDATORS
validates :hp, presence: true, blank: false, nill: false, numericality: { greater_than_or_equal_to: 0 }
validates :armor, presence: true, blank: false, nill: false, numericality: { greater_than_or_equal_to: 0 }
validates :token, presence: true, blank: false, nill: false, length: { is: 24 }, on: :save
validates :name, presence: true, blank: false, nill: false, length: { minimum: 4 }
# @!endgroup

end

迁移：

create_table :users do |t|
  t.references :chosen_deck, index: true, foreign_key: { to_table: :decks }
  t.string :name, null: false
  t.integer :hp, null: false, default: 20
  t.integer :armor, null: false, default: 0
  t.string :token, length: { is: 24 }, null: false

  t.timestamps
end

当我尝试用它保存游戏时出现的问题：

ActiveModel::MissingAttributeError: can't write unknown attribute `game_id`

我把截图放在这里：error screen

祝你有愉快的一天，

Answer 1

ActiveModel::MissingAttributeError: can't write unknown attribute game_id

问题正是错误所说的。 User 模型缺少 game_id 属性，这是连接用户和游戏的约定所必需的（如果您想要另一列，则应明确指定为 foreign_key）

只需为 users 创建一个 game_id 列并在 User 模型中指定（不是必需的）belongs_to :game，因为用户 belongs_to 一个游戏。

否则，由于您有user1_id和user2_id，您需要将has_one更改为belongs_to。然后它将更新这些 belongs_to 列，而不是在 has_one 关联中查找 game_id。

class Game < ApplicationRecord
  # @!group RELATIONS
  has_many :turns, dependent: :destroy
  has_many :play_cards, dependent: :destroy
  belongs_to :user1, class_name: 'User', dependent: :destroy
  belongs_to :user2, class_name: 'User', dependent: :destroy
  # @!endgroup
end

Rails 我的关系有问题

Rails Troubles with my relations

migration

ruby-on-rails

has-one

relation

belongs-to