Rails Engine configuration

Question

I'm developing a Rails Engine that handles the OAuth mechanism with a third party. I would like to have all the configuration in a Struct attribute, so all the engine config data is stored together:

require 'rails'


module ThirdParty
  class Engine < ::Rails::Engine

    initializer "third-party.some_init_task" do |app|
      ThirdPartyConfig = Struct.new(:uri, :client_id, :client_secret, :redirect_uri)

      app.config.thirdparty = ThirdPartyConfig.new
      app.config.thirdparty.uri = "https://thirdparty.com"
      app.config.thirdparty.client_id = ""
      app.config.thirdparty.client_secret = ""
      app.config.thirdparty.redirect_uri = ""
    end
  end
end

Some of the configuration should be defined in the application level initializers:

class Application < Rails::Application

    config.thirdparty.client_id = <valid_client_id>
    config.thirdparty.client_secret = <valid_client_secret>
    config.thirdparty.redirect_uri = <redirect_uri>
end

But as config.thirdparty still is undefined while loading the application initializer, it fails.

Answer 1

Try specifying the load order for the initializer in your engine. You should be able to force it to load before the application configuration runs. Here is a guess at the point you want to load your initializer

initializer "third-party.some_init_task", :before=> :load_config_initializers do |app|

If that does not work, try loading it before another initializer.