ruby - 如何测试是否正在使用某些特定的 Rack 中间件？

Question

更具体地说，我在这里谈论的是 sentry-raven 和 sinatra。我看到了测试 sinatra 应用程序或中间件的示例。但是我没有看到有人测试是否存在某些特定的中间件。或者我应该测试行为，而不是配置(或者我应该如何调用它)？

Answer 1

重要的是(我想说的)行为，但如果你想检查中间件，在深入研究 Sinatra source 之后，我建议有两种方法(可能有更简单/更好的方法):

环境

在 Sinatra 源代码中 there's a method that uses the env to check if a middleware is already present :

# Behaves exactly like Rack::CommonLogger with the notable exception that it does nothing,
# if another CommonLogger is already in the middleware chain.
class CommonLogger < Rack::CommonLogger
  def call(env)
    env['sinatra.commonlogger'] ? @app.call(env) : super
  end

你可以在一条路线上做同样的事情，例如

get "/env-keys" do
  env.keys.inspect
end

如果它在 env hash 中插入了一些东西，它只会向你显示中间件，例如

class MyBad
  def initialize app, options={}
    @app = app
    @options = options
  end

  def call env
    @app.call env.merge("mybad" => "I'm sorry!")
  end
end

输出:

["SERVER_SOFTWARE", "SERVER_NAME", "rack.input", "rack.version", "rack.errors", "rack.multithread", "rack.multiprocess", "rack.run_once", "REQUEST_METHOD", "REQUEST_PATH", "PATH_INFO", "REQUEST_URI", "HTTP_VERSION", "HTTP_HOST", "HTTP_CONNECTION", "HTTP_CACHE_CONTROL", "HTTP_ACCEPT", "HTTP_USER_AGENT", "HTTP_DNT", "HTTP_ACCEPT_ENCODING", "HTTP_ACCEPT_LANGUAGE", "GATEWAY_INTERFACE", "SERVER_PORT", "QUERY_STRING", "SERVER_PROTOCOL", "rack.url_scheme", "SCRIPT_NAME", "REMOTE_ADDR", "async.callback", "async.close", "rack.logger", "mybad", "rack.request.query_string", "rack.request.query_hash", "sinatra.route"]

它接近该列表的末尾。

中间件方法

There's also a method called middleware in Sinatra::Base :

  # Middleware used in this class and all superclasses.
  def middleware
    if superclass.respond_to?(:middleware)
      superclass.middleware + @middleware
    else
      @middleware
    end
  end

在模块化应用程序的类定义中调用它，您可以获得数组中的中间件:

require 'sinatra/base'

class AnExample < Sinatra::Base
  use MyBad
  warn "self.middleware = #{self.middleware}"

输出:

self.middleware = [[MyBad, [], nil]]

可能有一种方法可以从 Sinatra::Application 获取它，但我没看过。