面向软件专业人员的现代化架构设计模式

{"type":"doc","content":[{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"许多现代应用程序需要在企业规模上构建，有时甚至需要在互联网规模上构建。每个应用程序都需要满足可伸缩性、可用性、安全性、可靠性和弹性要求。在本文中，我将讨论一些可以帮助你轻松实现上述功能的设计模式。我将讨论每种模式，如何在云原生环境中使用该模式，以及何时使用何时不使用。其中一些模式并不新鲜，但在当前互联网规模的云计算世界中非常有用。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"italic"}],"text":"本文最初发布于BetterProgramming，经原作者授权由InfoQ中文站翻译并分享。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https:\/\/static001.infoq.cn\/resource\/image\/6f\/f5\/6f1b3b7dc01fa87567fbd3ace8bf86f5.png","alt":null,"title":"","style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"italic"}],"text":"图片来自："},{"type":"link","attrs":{"href":"https:\/\/undraw.co\/","title":"","type":null},"content":[{"type":"text","marks":[{"type":"italic"}],"text":"https:\/\/undraw.co\/"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"以下是本文将要讨论的模式："}]},{"type":"numberedlist","attrs":{"start":1,"normalizeStart":1},"content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":1,"align":null,"origin":null},"content":[{"type":"text","text":"断路器"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":2,"align":null,"origin":null},"content":[{"type":"text","text":"命令和查询职责分离（CQRS）"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":3,"align":null,"origin":null},"content":[{"type":"text","text":"事件源"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":4,"align":null,"origin":null},"content":[{"type":"text","text":"挎斗"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":5,"align":null,"origin":null},"content":[{"type":"text","text":"BFF（Backend-for-Frontend）"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":6,"align":null,"origin":null},"content":[{"type":"text","text":"Strangler"}]}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"让我们开始吧。"}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"断路器"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"分布式系统的设计应该考虑故障。如今，世界已经接纳了微服务，而这些服务大多依赖于其他远程服务。由于网络、应用程序负载等各种原因，这些远程服务可能无法及时响应。在大多数情况下，实现重试应该就能够解决问题。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"但有时候，可能会出现诸如服务降级或服务本身完全失败等重大问题。在这种情况下，不断地重试是没有意义的。这就用到断路器模式了。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https:\/\/static001.infoq.cn\/resource\/image\/95\/b8\/95c693294cf21c4f923dc359caf881b8.png","alt":null,"title":"","style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"italic"}],"text":"断路器，图片由作者提供。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"上图展示了断路器模式的实现，其中，当服务1识别出服务2被调用时存在连续故障\/超时时，服务1将自动断开服务2的调用并返回回退响应，而不是重试。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"有一些流行的开源库，比如"},{"type":"link","attrs":{"href":"https:\/\/github.com\/Netflix\/Hystrix\/wiki\/How-it-Works","title":"","type":null},"content":[{"type":"text","text":"Netflix的Hystrix"}]},{"type":"text","text":"，可以用来非常轻松地实现这种模式。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"如果你正在使用API网关或像Envoy这样的挎斗代理，那么这可以在代理层本身实现。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragra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