How is ExtensionLoader supposed to work?

[ronald]

I'm currently trying to run radiantcms on rails 6 beta.

Since i have no clue how ExtensionLoader is supposed to work, I fiddled with:
[main] application.rb: glob vendor/extensions and add paths to config.autoload_paths

    config.autoload_paths << Rails.root.join('lib/radiant-copy')
    extensions_sub_dirs = Dir.glob('vendor/extensions/**/*/').reject{|f| f=~ %r~/(db|recipes|public|spec|test|views)/~ }
    extensions = Dir.glob('vendor/extensions/*')
    extensions.each do |ext|
      ext_paths = extensions_sub_dirs.select{|d| d.include?(ext)}
      config.autoload_paths.concat(ext_paths)
    end

[radiant] engine.rb:

      el = Radiant::ExtensionLoader.instance
      el.extensions = Radiant::Engine.all_available_extensions
      el.extensions.each do |ext_name|
        ext = el.load_extension(ext_name)
        ext.activate
      end

I'm sure this is not the way EngineLoader is supposed to work.

To be more specfic:
What is Radiant::ExtensionLoader#initializer?
Where is Radiant::ExtensionLoader#gems?

Feedback highly appreciated, @jomz

[saturnflyer]

I haven't worked on the ExtensionLoader but I'll try to take a look and give some feedback

[saturnflyer]

Without diving in too deep, I'll give you some history @ronald
Radiant Extensions pre-exist Rails Engines.
Originally there was a UI that allowed you to turn on and off features provided by extensions, but that was dropped and the UI should only now show you the extensions and allow you to configure them (if they provide for that).
The trajectory was to move extensions to just adding them as gems gem "radiant-snippets-extension"
At this point, Extensions should just be Engines and there's support for that in Radiant::Engine.
Old extensions may exist that don't conform as an Engine. I'm ok with dropping support for extensions that are not engines.
I can't give you greater guidance on the particulars of the code since I don't know it well but I'll be happy to help you along with contributions.

[ronald]

Thx, Jim.

Do you have one working example of radiant (1.1.4 or 2.alpha) + engine based extension gem?

On Rubygems this one is most popular:
https://rubygems.org/gems/radiant-reader-extension
=> can't find source

Second one is https://github.com/squaretalent/radiant-shop-extension/tree/v0.11.6
=> does not use Rails::Engine

3rd https://rubygems.org/gems/radiant-event_calendar-extension
=> no source online

btw. did u see this one https://github.com/saturnflyer/radiant-snippets-extension/issues/1 ?

[saturnflyer]

source is here https://github.com/spanner/radiant-reader-extension

I'll see what I can find for other extensions

[jomz]

Hi Ronald, Jim,

Sorry to not reply here earlier...
The source for event_calendar is over here:
https://github.com/radiant/radiant-event-calendar-extension

.. but to answer your question Ronald; 1.1.4 does not support extensions as engines, as that is still on rails 2.3. To the best of my knowledge, the master branch is not ready to support extensions yet either.
I don't think anyone is using it in production, and I wouldn't recommend it either. It took me quite some hoop-jumping last week to just get an instance set up, and spotting several things along the way that still need fixing.
"The master branch may be broken." is probably understating it a bit...