Flask应用部署AWS Amplify遇404错误，求运行解决方案

问题背景 #

部署流程显示成功，但访问Amplify链接时出现错误：No webpage was found for the web address. HTTP error 404，构建日志中关键警告为：

!! No index.html detected in deploy folder: /codebuild/output/src3464593922/src/digital-me/

构建日志关键内容 #

## No backend environment association found, continuing...
Starting Frontend Build
                                 # Starting phase: build
                                 # Completed phase: build
2023-07-06T12:41:23.066Z [INFO]: ## Build completed successfully
2023-07-06T12:41:23.067Z [INFO]: # Starting caching...
2023-07-06T12:41:23.067Z [INFO]: Nothing to cache
2023-07-06T12:41:23.067Z [INFO]: # Caching completed
2023-07-06T12:41:23.069Z [INFO]: # No custom headers found.
**2023-07-06T12:41:23.083Z [WARNING]: !! No index.html detected in deploy folder: /codebuild/output/src3464593922/src/digital-me/**
2023-07-06T12:41:23.083Z [INFO]: # Starting build artifact upload process...
2023-07-06T12:41:23.380Z [INFO]: # Uploading build artifact '__artifacts.zip'...
2023-07-06T12:41:23.409Z [INFO]: # Uploading build artifact '__artifactsHash.zip'...
2023-07-06T12:41:23.579Z [INFO]: # Build artifact upload completed
2023-07-06T12:41:23.580Z [INFO]: # Starting environment caching...
2023-07-06T12:41:23.580Z [INFO]: # Uploading environment cache artifact...
2023-07-06T12:41:23.696Z [INFO]: # Uploaded environment cache artifact
2023-07-06T12:41:23.697Z [INFO]: # Environment caching completed
Terminating logging...

解决操作步骤 #

AWS Amplify默认适配静态前端站点，Flask是动态后端应用，需调整配置适配：

1. 修改构建与部署配置 #

在Amplify控制台的构建和测试设置中调整：

• 构建命令：替换为安装依赖并启动WSGI服务器的命令，示例：

  pip install -r requirements.txt && pip install gunicorn && gunicorn -w 4 -b 0.0.0.0:5000 app:app
  

  （app:app对应入口文件app.py中的Flask实例名，需根据实际代码修改）
• 部署目录：设置为Flask应用的根目录，无需指定静态文件目录

2. 确认应用基础配置 #

• 项目根目录下必须有requirements.txt，包含Flask、gunicorn等依赖，示例内容：

  Flask==2.3.3
  gunicorn==21.2.0
  

• 检查Flask入口文件（如app.py）存在根路由：

  from flask import Flask
  app = Flask(__name__)
  
  @app.route('/')
  def home():
      return "Flask App Running!"  # 或返回渲染的模板页面
  

3. 启用Amplify后端部署（稳定方案） #

若自定义构建命令无效，可使用Amplify后端托管功能：

• 在Amplify控制台添加后端环境，选择Python运行时
• 上传requirements.txt和Flask源码，配置启动命令为gunicorn app:app

4. 配置重写规则（解决路由跳转问题） #

如果访问动态路由仍报错，在Amplify的重写和重定向中添加规则：

• 源地址：</^[^.]+$|\.(?!(css|gif|ico|jpg|js|png|txt|svg|woff|woff2|ttf|map|json)$)([^.]+$)/>
• 目标地址：/
• 状态：200（Rewrite）

内容的提问来源于stack exchange，提问作者shrimaan0205