Question

Currently I have a User table that has a toys_owned column that is an embedded document. How do I set to nil/modify the embedded document in my rails console? Currently it is giving me a NoMethodError when I try to set it to nil.

Note: I’m trying to avoid using the mongo shell if possible

app/models/toysOwned.rb

class ToysOwned
  include Mongoid::Document

  embedded_in :user, :inverse_of => :toys_owned
  referenced_in :toy
end

Rails Console:

User.where(email: "[e-mail]").first.toys_owned
 => [#<ToysOwned _id: 7e5s72d19gb23f0001203025, toy_id: BSON::ObjectId('6g46af0g2ffchc000100003d')>]
ruby-1.9.2-p290 :049 > u = User.where(email: "[e-mail]").first.toys_owned.first
 => #<ToysOwned _id: 7e5s72d19gb23f0001203025, toy_id: BSON::ObjectId('6g46af0g2ffchc000100003d')>
ruby-1.9.2-p290 :051 > u = nil
 => nil 
ruby-1.9.2-p290 :052 > u.save
NoMethodError: undefined method `save' for nil:NilClass

app/models/user.rb (some of it)

class User
  include Mongoid::Document
  include Mongoid::Timestamps

  include ToyOwnable
  ...520 lines of code...
end

Answer 1

Try this, it should work:

user = User.where(email: "[e-mail]").first
user.toys_owned.shift
user.save

If you read your code for a couple of minutes, you’ll realize that you’re doing crazy things 🙂

First, you set u to a first of toys_owned. Then you set this reference u to nil. This does not affect original toys_owned collection. Then you’re trying to call a method on u (which is nil at the moment and can’t fulfill your request).