基于VSTS与Azure部署Loopback Node.js服务器的问题求助

Alright, let's tackle your problems step by step—you're hitting two key issues: a Node.js version mismatch causing that syntax error, and an incorrect project setup workflow in Visual Studio for Loopback. Here's how to fix everything:

1. Fix the "SyntaxError: Use of const in strict mode" Error #

This error is 99% due to an outdated Node.js version on your Azure Web App. Older versions (pre-v4.x) don't support const declarations in strict mode, which Loopback uses extensively. Here's how to update it:

• Head to the Azure Portal, navigate to your Web App.
• Go to Configuration > General settings, look for the Node.js version dropdown. Pick a version compatible with your Loopback setup: Loopback 3.x works best with Node.js 8.x+, while Loopback 4 needs 12.x or newer.
• Save the settings and restart your Web App—this should resolve the syntax error immediately.

2. Properly Create a Loopback Project in Visual Studio #

Starting with the "Basic Azure Node.js Web Application" template and retrofitting Loopback is causing misalignment. Instead, build your Loopback project correctly from the start:

• Open Visual Studio and create a new Blank Node.js Web Application (skip the Azure-specific template for now).
• Open the integrated terminal (View > Terminal) or Package Manager Console, then install the Loopback CLI globally:

  npm install -g loopback-cli
  

• Initialize your Loopback project by running:

  lb
  

• Follow the CLI prompts to set up your app (choose your application type, data sources, initial models, etc.).
• Once the project is generated, update your package.json to set the correct start script—this tells Azure how to launch your app:

  "scripts": {
    "start": "node server/server.js"
  }
  

• Now you can add your custom APIs, models, and business logic as needed.

3. Deploy to Azure Web App Correctly #

With your Loopback project set up properly, deploy it using these steps:

• Right-click your project in Solution Explorer, select Publish.
• Choose Azure as the target, then select your existing Web App or create a new one.
• In the publish wizard's Settings tab:
  • Set Deployment mode to match your Node.js setup (Framework-dependent works fine for most cases).
  • Ensure the Start command is set to npm start—this uses the script we defined in package.json to launch Loopback.
• Publish the project. After deployment, double-check the Node.js version in Azure Portal (as we did in step 1) to confirm it's the correct one.

4. Troubleshooting If Issues Persist #

If you still see errors after these steps:

• Enable detailed logging in Azure: Go to App Service Logs in your Web App settings, turn on Application Logging (Filesystem) and set the level to Verbose.
• Check logs via Log Stream in the Azure Portal, or use Kudu (Advanced Tools > Go) to access the LogFiles directory directly.
• Verify all dependencies are installed: In Kudu's debug console, navigate to site/wwwroot and run npm install to ensure no packages are missing or corrupted.

内容的提问来源于stack exchange，提问作者mks