Question

I have a rails app the works with multiple 3rd party APIs. Some of these APIs are rate limited and many have methods that can take hours to complete and you have to continually check to see if your request is ready. As such, I have built a queueing system to manage all the baggage.

Each request that goes into this queue has a JSON string that details which 3rd party API the request pertains to, which method, what arguments and a callback to handle the response. I’m going to need a good many callback methods and they handle wildly different tasks. Some update the service status of the 3rd party, some update customer information, some create another queued request to download a large CSV or parse a CSV, etc.

I’m not sure where to put all these unrelated callback methods. They are so varied and meddle with so many different models that I’m not sure it’s right to put them under the QueuedRequest model (although that seems the easiest especially regarding testing). I’d like to consolidate them in a single place (again to make testing easier) so trying to shoehorn them into their related models (though often they may not be related to a model at all) isn’t going to work.

A utility class of sorts seems to be the best place but where would I put that file?

Details:
Rails 3.2.6

---

Update: To elaborate on the answer below, what I ended up doing was putting a module of utility methods in /lib/api. I added /lib/api to my autoload_paths in /config/application.rb and, unmentioned, I created an initializer to load the module into my app for me.

/lib/api/callbacks.rb

module Callbacks
  extend self
  def some_method
    # magic
  end
end

/config/application.rb

config.autoload_paths += %W(#{config.root}/lib/api)

/config/initializers/application.rb

require 'callbacks'

Answer 1

Under the lib directory, and don’t forget to add it to your autoload paths (or eagerload paths if your app is threadsafe!). Make a folder called api and then stick that stuff in a namespace

For example, lib/api/stack_overflow.rb

module API
   class StackOverflow
     # schtuff
   end
end