如何在 AWS CodeBuild 中为 MERN 堆栈应用程序配置 buildspec.yml

如何解决如何在 AWS CodeBuild 中为 MERN 堆栈应用程序配置 buildspec.yml

我已经在 aws 中为 MERN 堆栈应用程序配置了 CodePipeline。当我将工件部署到 beanstalk 时，出现此错误。 Instance deployment Failed to generate a 'procfile' for Node.js. Provide one of these files: 'package.json','server.js',or 'app.js'. The deployment Failed.

MERN 应用程序结构

buildspec.yml

version: 0.2

phases:
  install:
    commands:
      - echo Installing Node 14...
      - curl -fsSL https://deb.nodesource.com/setup_lts.x | bash -
      - apt install -y nodejs
      - echo Installing Yarn...
      - curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add -
      - echo "deb https://dl.yarnpkg.com/debian/ stable main" | tee /etc/apt/sources.list.d/yarn.list
      - apt install --no-install-recommends yarn
  pre_build:
    commands:
      - echo Installing root dependencies
      - yarn install
      - echo Installing frontend dependencies
      - yarn --cwd frontend install
  build:
    commands:
      - echo Building...
      - yarn --cwd frontend run build
artifacts:
  files:
    - '**/*'
  discard-paths: no
  base-directory: frontend/build

我提供 frontend/build 目录作为 base-directory。这个错误的原因是什么？