You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: generic_instrumentation.rb
    path of file: ./repos/appsignal-ruby/lib/appsignal/rack
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require "rack"

module Appsignal
  # @api private
  module Rack
    class GenericInstrumentation
      def initialize(app, options = {})
   
    
      def call_with_appsignal_monitoring(env)
        request = ::Rack::Request.new(env)
        transaction = Appsignal::Transaction.create(
          SecureRandom.uuid,
          Appsignal::Transaction::HTTP_REQUEST,
          request
        )
        begin
          Appsignal.instrument("process_action.generic") do
            @app.call(env)
          end
        rescue Exception => error # rubocop:disable Lint/RescueException
          transaction.set_error(error)
          raise error
        ensure
          transaction.set_action_if_nil(env["appsignal.route"] || "unknown")
          transaction.set_metadata("path", request.path)
          transaction.set_metadata("method", request.request_method)
          transaction.set_http_or_background_queue_start
          Appsignal::Transaction.complete_current!
        end