attr_encrypted / ActiveRecord problem w. rack

I am using attr_encrypted from a rack/ruby script and it seems like there is some weird issue with ActiveRecord and attr_encrypted.

attr_encrypted works fine and the correct values are set in the object. The object is validated using ActiveModel, however when saving the object the values set by attr_encrypted are cleared (nil).

It works fine using the console and the object is saved to the database.

Using Ruby 2.2.2, Rails 4.2.2, PostgreSQL

Code example below to replicate the problem:

require 'attr_encrypted'
require 'active_model'
require 'active_record'

KEY = 'top secret'

# Our env

ENV["RAILS_ENV"] ||= "development"

# Our secret key

VAULT_ENTRY_KEY = 'secret'

# Model

require ::File.expand_path('./app/models/vault_entry.rb')

# Contents of vault_entry.rb

=begin
class VaultEntry < ActiveRecord::Base

  # Read only attributes

  attr_readonly :id, :created_at

  # Our encrypted attribute

  attr_encrypted :data, :key => VAULT_ENTRY_KEY, :mode => :per_attribute_iv_and_salt, :encode => true, :type => :string, :random_iv => true

  # Validations

  validates_presence_of :data, :encrypted_data_salt, :encrypted_data_iv

end
=end

# Migration for vault_entry (using schema_plus)

=begin
class CreateVaultEntries < ActiveRecord::Migration
  def change
    create_table :vault_entries, id: :uuid do |t|
      t.string :encrypted_data, null: false
      t.string :encrypted_data_salt, null: false
      t.string :encrypted_data_iv, null: false
      t.timestamps null: false
    end
  end
end
=end 

# Connect to the database

dbconfig = YAML::load(File.open('./config/database.yml'))
ActiveRecord::Base.establish_connection(dbconfig[ENV["RAILS_ENV"]])

entry = VaultEntry.new(:data => 'test')

# Examine the entry object

puts "DATA: #{entry.data}"
puts "ENCRYPTED_DATA: #{entry.encrypted_data}"
puts "ENCRYPTED_DATA_SALT: #{entry.encrypted_data_salt}"
puts "ENCRYPTED_DATA_IV: #{entry.encrypted_data_iv}"

# Is the object valid?

puts "Is the object valid? #{entry.valid?}"

=begin
DATA: test
ENCRYPTED_DATA: 6NBLFaaW415KIUNAaLQ19Q==
ENCRYPTED_DATA_SALT: 6851b995345ac0da
ENCRYPTED_DATA_IV: 7m8qT/JetxS1lOjyL751UA==
Is the object valid? true
=end

# Try to save the entry

entry.save

# Boom!

=begin
activerecord-4.2.2/lib/active_record/connection_adapters/postgresql_adapter.rb:602:in `exec_prepared': PG::NotNullViolation: ERROR:  null value in column "encrypted_data" violates not-null constraint (ActiveRecord::StatementInvalid)
DETAIL:  Failing row contains (b1ce54e6-9be2-41a6-a3c8-61d076f72b80, null, null, null, 2015-06-17 17:59:17.706087, 2015-06-17 17:59:17.706087).
: INSERT INTO "vault_entries" ("created_at", "updated_at") VALUES ($1, $2) RETURNING "id"
=end

attr-encrypted / attr_encrypted

attr_encrypted / ActiveRecord problem w. rack #166