面向軟件專業人員的現代化架構設計模式

{"type":"doc","content":[{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"許多現代應用程序需要在企業規模上構建，有時甚至需要在互聯網規模上構建。每個應用程序都需要滿足可伸縮性、可用性、安全性、可靠性和彈性要求。在本文中，我將討論一些可以幫助你輕鬆實現上述功能的設計模式。我將討論每種模式，如何在雲原生環境中使用該模式，以及何時使用何時不使用。其中一些模式並不新鮮，但在當前互聯網規模的雲計算世界中非常有用。"}]}]},{"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":"本文最初發佈於BetterProgramming，經原作者授權由InfoQ中文站翻譯並分享。"}]},{"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":"圖片來自："},{"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":"以下是本文將要討論的模式："}]},{"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":"斷路器"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":2,"align":null,"origin":null},"content":[{"type":"text","text":"命令和查詢職責分離（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":"挎鬥"}]}]},{"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":"讓我們開始吧。"}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"斷路器"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"分佈式系統的設計應該考慮故障。如今，世界已經接納了微服務，而這些服務大多依賴於其他遠程服務。由於網絡、應用程序負載等各種原因，這些遠程服務可能無法及時響應。在大多數情況下，實現重試應該就能夠解決問題。"}]},{"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":"但有時候，可能會出現諸如服務降級或服務本身完全失敗等重大問題。在這種情況下，不斷地重試是沒有意義的。這就用到斷路器模式了。"}]},{"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":"斷路器，圖片由作者提供。"}]},{"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":"上圖展示了斷路器模式的實現，其中，當服務1識別出服務2被調用時存在連續故障\/超時時，服務1將自動斷開服務2的調用並返回回退響應，而不是重試。"}]},{"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":"有一些流行的開源庫，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":"，可以用來非常輕鬆地實現這種模式。"}]},{"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網關或像Envoy這樣的挎鬥代理，那麼這可以在代理層本身實現。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragra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