shopify_api/lib/active_resource/json_errors.rb

require 'active_resource/base'

module ActiveResource
  class Errors < ActiveModel::Errors
    def from_json(json, save_cache = false)
      data = ActiveSupport::JSON.decode(json)['errors'] || {} rescue {}
      case data
      when String
        from_string(data, save_cache)
      else
        from_hash(data, save_cache)
      end
    end

    def from_hash(messages, save_cache = false)
      clear unless save_cache

      messages.each do |key,errors|
        errors.each do |error|
          add(key, error)
        end
      end
    end

    def from_string(error, save_cache = false)
      clear unless save_cache

      add("message", error)
    end
  end
end