Question

I’m an absolute beginner to Ruby on Rails; I literally started last night. I’m following the Getting Started with Rails tutorial, although I’ve made a few modifications. Instead of a blog with posts and comments, I’m making a simple task-tracking application in which Projects have Tasks associated with them.

Everything was going quite well until step #9 (Deleting Comments). According to the tutorial, I should be able to get the parent model for a comment by calling comment.post, the analogue of which in my case is task.project. But when Rails tries to render the partial in which I’ve got task.project, it raises a NoMethodError:

undefined method `project' for #<Task:0x7fb0011cf058>

My models are as follows:

class Project < ActiveRecord::Base
  validates :name, :presence => true

  has_many :tasks, :dependent => :destroy
end

class Task < ActiveRecord::Base
  validates :name, :presence => :true

  belongs_to :project
end

Using the rails console, I determined that my tasks do have a project_id method which returns the ID of the associated project. Thus, I can get around the problem by using Project.find(task.project_id) instead of task.project in my partial. That seems “wrong,” though, and makes me wonder if the relationship between my two models is somehow broken.

What’s going on here?

Update: If I comment out the validates line in the Task model, then all of its methods work properly. I don’t understand why that is the case, though.

Update 2: Figured it out. I was using the symbol :true instead of the simple boolean value in the validates line of my Task model. Had I paid more attention to the stack trace in the first place, I would have figured it out much sooner. What an embarrassing mistake!

Answer 1

Your code looks perfect. But if you were trying that into console try reloading first and then try again

reload!
task = Task.find(<record-id>)
task.project

It should be working.