undefined method `has_one_attached' - Spree, AWS S3, Product Images, Rails

Question

I'm trying to connect my Spree shopping cart with AWS S3 for product image uploads but I keep getting the error:

.rbenv/versions/2.4.0/lib/ruby/gems/2.4.0/gems/activerecord-5.2.0/lib/active_record/dynamic_matchers.rb:22:in `m
ethod_missing': undefined method `has_one_attached'

Here is my set-up:

Gemfile

ruby '2.4.0'
gem 'rails', '~> 5.2.0'
gem 'spree', '~> 3.6.0'
gem 'spree_auth_devise', '~> 3.3'
gem 'spree_gateway', '~> 3.3'
gem 'globalize', github: 'globalize/globalize'
gem 'spree_i18n', github: 'spree-contrib/spree_i18n'
gem 'spree_globalize', github: 'spree-contrib/spree_globalize', branch: 'master'
gem 'spree_static_content', github: 'spree-contrib/spree_static_content'
gem 'aws-sdk', '~> 2.3'

config/initializers/spree.rb

attachment_config = {

    s3_credentials: {
      access_key_id:     ENV['AWS_ACCESS_KEY_ID'],
      secret_access_key: ENV['AWS_SECRET_ACCESS_KEY'],
      bucket:            ENV['S3_BUCKET_NAME']
    },

    storage:        :s3,
    s3_region:      ENV['S3_REGION'],
    s3_headers:     { "Cache-Control" => "max-age=31557600" },
    s3_protocol:    "https",
    bucket:         ENV['S3_BUCKET_NAME'],
    url:            ":s3_domain_url",

    styles: {
        mini:     "48x48>",
        small:    "100x100>",
        product:  "240x240>",
        large:    "600x600>"
    },

    path:           "/:class/:id/:style/:basename.:extension",
    default_url:    "/:class/:id/:style/:basename.:extension",
    default_style:  "product"
  }

  attachment_config.each do |key, value|
    Spree::Image.attachment_definitions[:attachment][key.to_sym] = value
  end

Has anyone come across this error and has a solution?

Answer 1

For anyone having this problem in the future, this is how I've fixed it.

If you are editing the Spree::User class as an initializer, the problem is that the initializer from 'active_storage/reflection' did not run. So add these lines at the beggining of your class_eval block:

include ActiveStorage::Reflection::ActiveRecordExtensions

ActiveRecord::Reflection.singleton_class.prepend(ActiveStorage::Reflection::ReflectionExtension)

include ActiveStorage::Attached::Model

Afterwards, ActiveStorage should be loaded and you will be able to find the method has_one_attached :image