Nested comments from scratch

Question

Let\'s say I have a comment model:

class Comment < ActiveRecord::Base
    has_many :replies, class: \"Comment\", foreign_key: \"reply_id\"
end
         


        

Answer 1

This will be my approach:

• I have a Comment Model and a Reply model.
• Comment has_many association with Reply
• Reply has belongs_to association with Comment

• Reply has self referential HABTM

  class Reply < ActiveRecord::Base
    belongs_to :comment
    has_and_belongs_to_many :sub_replies,
                    class_name: 'Reply',
                    join_table: :replies_sub_replies,
                    foreign_key: :reply_id,
                    association_foreign_key: :sub_reply_id
  
    def all_replies(reply = self,all_replies = [])
      sub_replies = reply.sub_replies
      all_replies << sub_replies
      return if sub_replies.count == 0
      sub_replies.each do |sr|
        if sr.sub_replies.count > 0
          all_replies(sr,all_replies)
        end
      end
      return all_replies
    end
  
  end 
  

  Now to get a reply from a comment etc:

• Getting all replies from a comment: @comment.replies
• Getting the Comment from any reply: @reply.comment
• Getting the intermediate level of replies from a reply: @reply.sub_replies
• Getting all levels of replies from a reply: @reply.all_replies