code: function popsicleServer (app) {
    var server = serverAddress(app)
  
    return function (req, next) {
      server.listen()
  
      req.url = server.url(req.url)
  
      return promiseFinally(next(), function () {
        server.close()
      })
    }
  }
docs: Create a request interceptor that listens and disconnects automatically.
  
  @param  {Function} app
  @return {Function}