Snippet

Ensuring Server-Side Execution with 'server-only'

The 'server-only' package is a build-time check that ensures modules containing sensitive logic (like API keys or direct DB access) are never accidentally imported into Client Components, which would leak them to the browser.

snippet.js

javascript

import 'server-only';
 
export async function getPrivateData() {
  const res = await fetch('https://api.internal.com/data', {
    headers: { Authorization: process.env.API_KEY },
  });
  return res.json();
}

nextjs

Breakdown

import 'server-only';

Triggers a build error if any part of this file is bundled for the client.

process.env.API_KEY

Environment variables are safely accessed here as the code is guaranteed to stay on the server.

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Ensuring Server-Side Execution with 'server-only'

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