如何在Heroku服务器上管理ReactJS文件？为何部署后仅能查看内存无法查看文件？

Hey there! Let's break down your Heroku questions step by step—since you're already familiar with deploying sites there, this should be straightforward.

You mentioned you can check memory usage but can't view server files. Heroku's dynos use an ephemeral filesystem, but you can still access and inspect files using these methods:

• Launch an interactive shell to navigate the dyno's filesystem directly. Run this command in your local terminal:

  heroku run bash --app your-app-name
  

  Once inside, you can use standard Unix commands like ls, cat, cd, and find to explore files and directories. For example, ls /app will show the root of your deployed app.

• Download specific files to your local machine if you need to examine them in detail. Use:

  heroku ps:copy /path/to/your/file --app your-app-name
  

  This will save the file to your current local directory.

Quick note: Since dynos restart frequently, any files you modify directly in the dyno won't persist. Always make changes locally and redeploy instead.

For React apps (especially those built with Create React App), Heroku handles most of the build process automatically, but here's how to manage your files effectively:

• Deploying updates:

  1. Make your changes to your local React code (edit components, update assets, etc.).
  2. Commit the changes to Git:

     git add .
     git commit -m "Update React components"
     

  3. Push to Heroku to redeploy:

     git push heroku main
     

  Heroku will automatically run npm install and npm run build (if your package.json has a build script, which Create React App sets up by default) to generate the production-ready static files.

• Inspecting deployed React build files:
  After deployment, you can use the heroku run bash command mentioned earlier to navigate to the /app/build directory—this is where Heroku stores the compiled React static files (HTML, CSS, JS bundles). Run ls /app/build to see the contents.

• Customizing the build process:
  If you need to run additional steps before or after building, add scripts to your package.json. For example, a heroku-postbuild script can handle extra tasks:

  "scripts": {
    "build": "react-scripts build",
    "heroku-postbuild": "some-additional-command"
  }
  

• Managing environment variables:
  For React-specific environment variables (like API URLs), prefix them with REACT_APP_ and set them via Heroku:

  heroku config:set REACT_APP_API_URL=https://your-api.com --app your-app-name
  

  These variables will be injected into your React app during the build process.

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