Question

I’m trying to have two documents one for posts and one for replies, and connect them using “Referenced 1-N” relationship.

From what I read from the mongoid documentation, all you have to do is add has_many and belongs_to into both classes and mongoid will allow me to add child documents that points to the parent.

So what I want to do simply is

1. create a new reply document that points to the parent
2. if possible have an array that holds ids of the children

I’ve tried to access reply from post in all ways and it doesn’t work. So it would be great if someone can crack this puzzle for me 🙂

Output

undefined method ‘reply’ for #< PostsController: >

Model

class Post
  include Mongoid::Document
  has_many :replies
  field :text,:type => String
end

class Reply
  include Mongoid::Document
  belongs_to :post
  field :name, :type => String
  field :text, :type => String
end 

Controller

def create_reply
  post = Post.find(params[:post_id])
  post.reply.new(params[:post])
end

Answer 1

reply is undefined for your Post class because Post has many replies, not reply.

Try writing post.replies.new(params[:post]) in your create_reply method instead.