I have written a module - JsonLog - that uses the append_info_to_payload hook provided by Rails to add some custom metrics to the logging instrumentation. I want to include/mixin this module in all the controllers of ActiveAdmin.
I've tried the following, and it works...
ActiveAdmin.register MyModel do
controller do
include JsonLog
end
end
...but this will force to me write the boilerplate code in every single model/controller that I'm registered with ActiveAdmin. How do I do this in one place (and in the process also ensure that this boilerplate is never missed out)?
Don't be shy to read the source. There is an ActiveAdmin::BaseController that inherits from InheritedResources::Base that in turn inherits from your ApplicationController. If you really need to specifically modify ActiveAdmin::BaseController then try this in config/initializers/active_admin.rb:
ActiveAdmin::BaseController.class_eval do
include JsonLog
end
Related
I am trying to define some helper methods to be used in the app's controller, but it seems that rails don't even call the controller. just for the test I have the following controller in my app/controllers/my_engine/application_controller.rb and as the documents say rails should find it first and an error should raise because THIS_SHOULD_PRODUCE_ERROR is unknown, but the rspec happily executing without any errors!
class ApplicationController < ActionController::Base
THIS_SHOULD_PRODUCE_ERROR
end
I even tried to mimic the devise's way but the results are the same!
The guide section on the app directory suggests that the application_controller in an engine "will provide any common functionality for the controllers of the engine".
So I wouldn't expect that any additions to that controller will be available to all controllers in an application.
That also means that your application_controller is, I suspect, not getting called when you're running your test. Which would explain why you're not seeing an error.
In terms of how devise does it I think you need to be looking at how define_helpers works. The code you've linked to in your question is the application controller in the test app for the devise gem.
I noticed that I have got things wrong, and the application_controller in the engine does not get applied to application_controller in the app! Also, I couldn't figure out how the devise did it, but I have come up with the simple workaround for this:
require_relative 'controllers/helpers'
module Acu
module Injectors
class << self
ActiveSupport::Notifications.subscribe "start_processing.action_controller" do |**args|
eval((Acu::Configs.get :base_controller).to_s).class_eval do
include Acu::Controllers::Helpers
end
end
end
end
end
This will inject controller helpers to the user's base controller (which I get from the user, default: :ApplicationController) at the end of the class, which is perfect for me (but don't know how to add it to begging of the class if anyone needs it)
I've created an RoR-App and I want to add a simple blog as engine that is already mountet to /blog where users can have their own blog. Now I didn't find anything how I can use the model user.rb in my blog engine.
In my main app I can use current_user.username but in my engine I can't use it.
There are (at least) two ways to achieve this:
Inherit your controller class from the main application's ApplicationController:
class MyEngine::ApplicationController < ::ApplicationController
end
This way it will have access to all the same helpers that have already been configured there. As a downside, this might drag in unwanted functionality, too.
Manually include the Devise controller helpers:
class MyEngine::ApplicationController
include Devise::Controllers::Helpers
define_helpers(Devise.mappings[:user])
end
I'm writing a configurable Rails engine. I have an authentication_helper configuration option to define which helper should be called in a before_action in all controllers needing authentication.
The problem is that I don't have access to the parent app's helpers from the engine's controllers. My understanding is that this happens because the engine is isolated.
I have considered using a block instead of a method name, but I'm not sure if that would work, or if I would be able to cleanly access the authorization logic from outside my controllers.
Active Admin, which I have used in the past, has a similar configuration option. I have noticed that their engine is not isolated, so perhaps I'm overrating the importance of engine isolation?
Is there an elegant way to have the benefits of engine isolation while also allowing this kind of customization? Or should I just forego isolation altogether?
EDIT #1
Brad Werth pointed my in the right direction, as this works with a regular controller inheriting from ApplicationController::Base:
module MyBigFancyEngine
class Engine < Rails::Engine
isolate_namespace MyBigFancyEngine
config.to_prepare do
# Make the implementing application's helpers available to the engine.
# This is required for the overriding of engine views and helpers to work correctly.
MyBigFancyEngine::ApplicationController.helper Rails.application.helpers
end
end
end
However, my engine's ApplicationController inherits from RocketPant::Base, which does not provide a helper method. I've tried to use a simple include (which works fine for regular controllers), but that doesn't work either (the controller can't find the helper).
Any ideas?
You can expose the implementing application's helpers available to the engine by including the following code in your engine.rb file:
engine.rb
module MyBigFancyEngine
class Engine < Rails::Engine
isolate_namespace MyBigFancyEngine
config.to_prepare do
# Make the implementing application's helpers available to the engine.
# This is required for the overriding of engine views and helpers to work correctly.
MyBigFancyEngine::ApplicationController.helper Rails.application.helpers
end
end
end
The RailsAdmin Engine is also isolated, but they have the same configuration options as you would like to implement. They have configurable before_filters for both authentication and authorization. Have a look at this.
As far as I can tell, they just subclass the parent controller like this::ApplicationController or instead you can configure one (ref).
For your controller you could just create your own EngineController, that inherits from RocketPant::Base and maybe just create a method there that calls the configured authentication method directly via send on the parent controller.
As the RocketPant::Base Class does not inherit from ApplicationController::Base I guess you have to find some custom way around this and can't go the normal ways for Rails Engines. Maybe you could also try to file an issue to the rocket_pant repo, to add the helper method. As far as I read they soon want to inherit from ApplicationController::Base anyway in 2.0 (ref).
I think you impulse on keeping the isolation is good - because a solution that relies on a method 'just being there' is a pain to debug if s.th. goes wrong in the app using your gem (i.e. typo in method name).
Further if your gem evolves, an some day it won't need the method, in an explicit way it's very convient to give a meainingful error:
You could provide a config method to be called in an initializer:
YourGem.configure do |config|
config.add_callback { MyApp.doIt() }
end
I found this discussion particularly insightful. There are also some interesting ideas in the Rails Engine API under Isolated engine helpers.
The Rails Engine API docs helped me figure out a good solution for url_helpers
You probably moved on by now, but if anyone else needs access to the "parent app" application helpers. You could always just include it explicitly in the application controller in your engine. like so:
include Rails.application.helpers
I have two namespaces, each with its own controller and presenter classes:
Member::DocumentsController
Member::DocumentPresenter
Guest::DocumentsController
Guest::DocumentPresenter
Both presenters inherit from ::DocumentPresenter.
Controllers access their respective presenters without namespace specified, e.g.:
class Guest::DocumentsController < ActionController::Base
def show
DocumentPresenter.new(find_document)
end
end
This usually calls presenter within same namespace. However sometimes in development environment I see base ::DocumentPresenter is being used.
I suspect the cause is that base ::DocumentPresenter is already loaded, so Rails class auto-loading doesn't bother to look further. Is this likely the case? Can it happen in production environment too?
I can think of two solutions:
rename base class to DocumentPresenterBase
explicitly require appropriate presenter files in controller files
Is there a better solution?
You are correct in your assumptions - If you do not specify namespace, Ruby starts from current namespace and works its way up to find the class, and because the namespaced class is not autoloaded yet, the ::DocumentPresenter is found and autoloader does not trigger.
As a solution I would recommend renaming ::DocumentPresenter to DocumentPresenterBase, because this protects you from bugs when you forget namespacing or explicit requiring somewhere.
The second option to consider would actually be using specific namespaced classnames all over the place, but this suffers from bugs when you accidentally forget to namespace some call.
class Guest::DocumentsController < ActionController::Base
def show
Guest::DocumentPresenter.new(find_document)
end
end
Third option would be your second - explicitly require all the classes in initializer beforehand. I have done this with Rails API which receives embedded models in JSON and Rails tends to namespace them when the actual models are not loaded yet.
Option 3.5 You could probably trick autoloader to do the heavy lifting (though, this might seem more like a hack):
class Guest::DocumentsController < ActionController::Base
# trigger autoload
Guest::DocumentPresenter
def show
# This should refer Guest::DocumentPresenter
DocumentPresenter.new(find_document)
end
def show
# As will this
DocumentPresenter.new(find_document)
end
end
Still the cleanest would be to rename the base class.
I think in 3 solutions if you want to mantein the name, one is your second solution.
1) explicitly require appropriate presenter files in controller files
2) Execute the full environment class path, like:
class Guest::DocumentsController < ActionController::Base
def show
Guest::DocumentPresenter.new(find_document)
end
end
3) Create a file on initialize directory and execute require manually (the worst options :S)
I want to create a set of methods that are available to my models, controllers, views and RSpec.
Please note I don't want to test these methods in RSpec, I want them available to RSpec to use.
The reason I want to do this is that I have some helpers which override the Rails path_helper methods. Since those path helper methods get used directly in all of these different places I need to mix them in as such.
Hm, it is several ways to achieve your goal, one of them is to include your module with methods direct in ActiveRecord::Base, 'ApplicationController' and Rspec.
Not sure about RSpec (I don't quite sign with it's class/module structure) but you can do something like this in some initializer file:
class ActiveRecord::Base
include MyModuleWithAwesomeMethods
end
class ApplicationController
include MyModuleWithAwesomeMethods
end
etc. for other classes/modules
Hope it will help you.