Rack Middleware in Rack Middleware? - ruby

Question

I am trying to build a rack middleware GEM that uses rack middleware itself (RackWired).
I have an existing application, whose config.ru uses Rack::Builder. In that block (Rack::Builder), I would like to specify my middleware, and when it is called to use a third party middleware (rack-cors) inside my own to do some stuff. Confusing I know.
The problem is that Rack::Builder's context is in config.ru and my middleware (RackWired) is thus unable to access it to "use" the third party middleware (rack-cors).
The intent of my effort is here
Is there a way to use middleware within middleware?
Thank you

Answer 1

Right, I'm not entirely sure what you're trying to do. But you can do this
class CorsWired
def initialize(app)
#app = app
end
def call(env)
cors = Rack::Cors.new(#app, {}) do
allow do
origins '*'
resource '*', :headers => :any, :methods => [:get, :post, :put, :options, :delete], :credentials => false
end
end
cors.call(env)
end
end
Your config.ru should have use CorsWired though, not use CorsWired.new
This is I think what you were asking but I think you're missing the point of middleware. You should just change your config.ru to use rack-cors before/after your middleware depending on what you want to do.
require 'rack'
require 'rack/cors'
require './cors_wired'
app = Rack::Builder.new do
use Rack::Cors do
allow do
origins '*'
resource '*', :headers => :any, :methods => [:get, :post, :put, :options, :delete], :credentials => false
end
end
use CorsWired
run lambda { |env| [200, {'Content-Type' => 'text/plain'}, ['OK']] }
end
run app