How can flex support elasticsearch functions in test environment?

[ChunAllen]

Hi @ddnexus I'm moving the flex functions to its model and made is as callback for example:

Here's my model Category

class Category < ActiveRecord::Base 
  after_create :create_by_flex
  after_update :update_by_flex
  after_destroy :destroy_by_flex

  private
    def create_by_flex
      flex_store
    end

    def update_by_flex
      flex_store
    end

    def destroy_by_flex
      flex_remove
    end
end

Now I'm having error with my test environment because it cannot see the `flex functions.
How can we mock elasticsearch/flex functions in test environment?