docs: improve runtimeConfig example

[duvior]

Made the nuxt.config.ts example using .env, a little more explicit.

🔗 Linked issue

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality like performance)
• ✨ New feature (a non-breaking change that adds functionality)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.

[netlify]

✅ Deploy Preview for nuxt3-docs ready!

Name	Link
🔨 Latest commit	7ad9f1f
🔍 Latest deploy log	https://app.netlify.com/sites/nuxt3-docs/deploys/62cec0233883a10008749eb0
😎 Deploy Preview	https://deploy-preview-5785--nuxt3-docs.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site settings.

[danielroe]

This won't work as written. The point being made above is:

For this to work, you must have a fallback value (which can just be an empty string) defined in your nuxt.config.

We're trying to avoid the situation where someone thinks that just because they have apiSecret: process.env.NUXT_API_SECRET defined in the config, that this will therefore means it gets overriden in production. (It won't work unless NUXT_API_SECRET is defined at build-time.

Instead, it must be at least: apiSecret: process.env.NUXT_API_SECRET || ''.

We also want to make it clear that the name of the environment variable is determined by the key within runtimeConfig - e.g. apiSecret becaomes NUXT_API_SECRET rather than by the environment variable passed as the default variable.

Any thoughts about how to make the above clearer in the example would be welcome.

[pi0]

Any thoughts about how to make the above clearer in the example would be welcome.

We might use comments in the docs after the value: (example)

var: '' // Can be overridden by NUXT_APP_VAR environment variable

[danielroe]

Let's go with @pi0's suggestion, which I think is clearer.