title: How to use http basic auth in Rails Metal?
body: <p>I'm trying to implement http basic authentication in rails metal. 
  Using this code:</p>
  
  <pre><code>class Api
    def self.call(env)
      if env["PATH_INFO"] =~ /^\/client/
  
      Rack::Auth::Basic.new(env) do |user, password|
        raise 'ERROR'
      end
  </code></pre>
  
  <p>But this block never executed? Any help will be appreciated! </p>