in Sinatra how do you make a "before" filter that matches all routes except some

Question

I have a Ruby Sinatra app and I have some code which I need to execute on all routes except for a few exceptions. How do I do this?

If I wanted to execute the code on selected routes (whitelist style) I'd do this:

['/join', "/join/*", "/payment/*"].each do |path|     before path do         #some code     end end 

How do I do it the other way round though (blacklist style)? I want to match all routes except '/join', '/join/*' and '/payment/*'

Answer 1

With negative look-ahead:

before /^(?!\/(join|payment))/ do   # ... end 

With pass:

 before do    pass if %w[join payment].include? request.path_info.split('/')[1]    # ...  end 

Or you could create a custom matcher.