Question

I have a project that uses Sinatra for static pages and Rails for the application.

I allow the request to hit one or the other by doing this in config.ru:

run Rack::Cascade.new([
  EightyEightTactical::Root,
  EightyEightTactical::Application
])

Where EightyEightTactical::Root is a subclass of Sinatra::Base and EightyEightTactical::Application is a subclass of Rails::Application.

I’m in a tricky situation where I need to set a flash message in a Rails controller and display it in a Sinatra layout.

I notice that Rails uses ActionDispatch::Flash in middleware, but I can’t seem to figure out how to access the flash messages outside of a Rails app. Am I mistaken, or can this be done?

Answer 1

Assuming you are using a Cookie session store, you can do the following:

1) Access the session cookie with the name specified in config/initializers/session_store.rb.

2) Decrypt the session cookie to get the session hash

3) Access the key called flash which contains a hash.

4) Iterate and display the flash message.

You should look at ActionController::Session::CookieStore class for more details.