从 Flask 到 FastAPI 的平滑迁移

{"type":"doc","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","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":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"本文将介绍 FastAPI 背后的基本概念，以及将 Flask 服务器过渡到 FastAPI 服务器所涉及的步骤和代码对比以供参考。根据 官方文档，FastAPI 的框架是："}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"… 一个现代、快速（高性能）的 Web 框架，基于标准 Python 类型提示，使用 Python 3.6+ 构建 API。"}]}]},{"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":"众所周知，Flask 是百分百 WSGI（Web Server Gateway Interface，Web 服务器网关接口）的微型 web 框架。随着发展，ASGI（Asynchronous Server Gateway Interface，异步服务器网关接口）作为 WSGI 精神的继承者，实现了在 I\/O 绑定的语境下的高吞吐量，支持 HTTP\/2 以及 WebSockets，这些都是 WSGI 所不能及的。"}]},{"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":"随着科技的发展，快如闪电的 ASGI 服务器 Uvicorn 诞生了。然而，Uvicorn 也仅仅只是一个不具备任何路由功能的 web 服务器。Starlette 的出现则是在 ASGI 的服务器（Uvicorn、Daphne，以及 Hypercorn）的基础上提供了一套完整的 ASGI 工具箱。如果要说这二者有什么直接的区别，Starlette 是 ASGI 的 web 框架，而 Flask 则是 WSGI 的 web 框架。"}]}]}