Question

I’ve been having problems deleting en embedded document in my Sinatra application, running Mongoid 2.4. Here is a basic overview of my models’ relationships:

class User
    has_many :posts
end

class Post
    belongs_to :user
    embeds_many :comments
    embeds_many :likes, as: :likeable
end

class Comment
    field :poster_id, type: String
    embedded_in :post
    embeds_many :likes, as: :likeable
end

class Like
    field :user_id, type: String
    embedded_in :likeable, polymorphic: true
end

The deletion code starts like this, without problems:

# Deletes comments the user created
Post.where('comments.poster_id' => params[:userid]).each do |post|
    post.comments.where(poster_id: params[:userid]).delete_all
end

# Delete likes on posts the user created
Post.where('likes.user_id' => params[:userid]).each do |post|
    post.likes.where(user_id: params[:userid]).delete_all
end

However, when trying to delete likes of comments of posts, mongoid fails. It seems it cannot go two levels deep:

# Delete likes on comments the user created (broken)
Post.where('comments.likes.user_id' => params[:userid]).each do |post|
  post.comments.likes.where(user_id: params[:userid]).delete_all
end

How can I delete them?

Answer 1

# Delete likes on comments the user created (not broken anymore)
Post.where('comments.likes.user_id' => params[:userid]).each do |post|
  post.comments.each {|c| c.likes.where(user_id: params[:userid]).delete_all }
end

You need to iterate on the comments, comments.likes must be giving you error, is it not?