Elasticsearch - Auto-import records from Active Record model

Question

System:

• Rails 4
• Ruby 2
• Elasticsearch 1.6.0

I'm using Elasticsearch to filter records and calculate statistics for my Active Record models. I'd like my Elasticsearch indices to mirror my Postgres database so that existing records are imported into my indices, new records are indexed as they are created, etc.

I have a concern that two of my models include like so:

# app/models/concerns/foo.rb
module Foo
  extend ActiveSupport::Concern

  included do
    include Elasticsearch::Model
    include Elasticsearch::Model::Callbacks

    self.import force: true
  end

  class_methods do
    def statistics(filter = {})
      # ES extended_stats aggregations
    end
  end
end

# app/models/bar.rb
# Same for another class
class Bar < ActiveRecord::Base
  include Foo
end

However, when I open the Rails console and call Bar.statistics, I get nilin every field. If I then execute Bar.import force: true and then Bar.statistics, I get correct, non-nil values in my extended stats aggregation.

Something else that might be of note: When I opened foo.rb in my Rails console using Pry and then exited, I ran into a Cannot define multiple included blocks for a Concern error (though loading the application works fine).

Am I missing something to make my records auto-import into ES?