Ruby on rails Rails在创建关系模型但未保存时验证是否存在

我有两个模型Task和dependcytask，它们之间的关系在代码中非常清楚

当我尝试保存任务时，DependencyTask属性的验证任务存在：true给出了您可以看到的错误，因为任务模型尚未保存

如何在不删除验证的情况下解决此问题：任务

型号：

class DependencyTask < ActiveRecord::Base
  belongs_to :task
  belongs_to :before, :class_name => "Task"

  validates :before, presence: true
  validates :task, presence: true
  validates :before_id, uniqueness: {scope: :task_id,
    message: "No puede ser la misma tarea dependiente de si misma"}

end

class Task < ActiveRecord::Base
  has_many :assignment_tasks, dependent: :destroy
  has_many :users, through: :assignment_tasks

  has_many :dependency_tasks, dependent: :destroy
  has_many :befores, :through => :dependency_tasks
  has_many :inverse_dependency_tasks, :class_name => "DependencyTask", :foreign_key => "before_id", dependent: :destroy
  has_many :inverse_befores, :through => :inverse_dependency_tasks, :source => :task

  accepts_nested_attributes_for :dependency_tasks

end

class DependencyTask < ActiveRecord::Base
  belongs_to :task, inverse_of: :dependency_tasks
  belongs_to :before, :class_name => "Task", inverse_of: :dependency_tasks

end



class Task < ActiveRecord::Base   

  has_many :dependency_tasks, dependent: :destroy, inverse_of: :task
  has_many :befores, :through => :dependency_tasks, inverse_of: :dependency_tasks
  has_many :inverse_dependency_tasks, :class_name => "DependencyTask", :foreign_key => "before_id", dependent: :destroy, inverse_of: :task
  has_many :inverse_befores, :through => :inverse_dependency_tasks, :source => :task, inverse_of: :inverse_dependency_tasks
end

错误：

["Dependency tasks task Can't be blank"]
{
    :"dependency_tasks.task" => [
        [0] "Can't be blank"
    ]
}

---

所有有帮助的评论都将非常感谢。

我使用逆方法解决这个问题

型号：

class DependencyTask < ActiveRecord::Base
  belongs_to :task
  belongs_to :before, :class_name => "Task"

  validates :before, presence: true
  validates :task, presence: true
  validates :before_id, uniqueness: {scope: :task_id,
    message: "No puede ser la misma tarea dependiente de si misma"}

end

class Task < ActiveRecord::Base
  has_many :assignment_tasks, dependent: :destroy
  has_many :users, through: :assignment_tasks

  has_many :dependency_tasks, dependent: :destroy
  has_many :befores, :through => :dependency_tasks
  has_many :inverse_dependency_tasks, :class_name => "DependencyTask", :foreign_key => "before_id", dependent: :destroy
  has_many :inverse_befores, :through => :inverse_dependency_tasks, :source => :task

  accepts_nested_attributes_for :dependency_tasks

end

class DependencyTask < ActiveRecord::Base
  belongs_to :task, inverse_of: :dependency_tasks
  belongs_to :before, :class_name => "Task", inverse_of: :dependency_tasks

end



class Task < ActiveRecord::Base   

  has_many :dependency_tasks, dependent: :destroy, inverse_of: :task
  has_many :befores, :through => :dependency_tasks, inverse_of: :dependency_tasks
  has_many :inverse_dependency_tasks, :class_name => "DependencyTask", :foreign_key => "before_id", dependent: :destroy, inverse_of: :task
  has_many :inverse_befores, :through => :inverse_dependency_tasks, :source => :task, inverse_of: :inverse_dependency_tasks
end

class DependencyTask“Task”，与：：dependency\u tasks相反
终止
类任务:dependency\u任务，与：：dependency\u任务相反
有很多：反向依赖任务，：class\u name=>“DependencyTask”，：foreign\u key=>“before\u id”，dependent:：destroy，反向依赖任务：：task
之前有很多：反向任务，：通过=>:reverse\u dependency\u任务，：source=>:task，reverse\u of:：reverse\u dependency\u任务
终止

你在使用观察员吗？我不知道这是什么