How to change request headers with server middleware – Nuxt.js

The Problem:

In Nuxt 3, server middleware can modify request headers. The goal is to add an authorization header with a bearer token to all requests via server middleware. However, the provided code doesn’t seem to be working, and the request headers remain unchanged. The task is to identify which property needs to be modified to successfully add the authorization header.

The Solutions:

Solution 1: Using `useRequestHeaders` Composable to Attach Cookies to Headers

To send cookies and other request headers via server middleware, you can use the useRequestHeaders composable. This composable allows you to access and modify the request headers for specific API routes.

Example: Attaching Cookies to Headers for an API Route

<script lang="ts" setup>
  const { data } = await useFetch('/api/test', {
    headers: useRequestHeaders(['cookie'])
  })
</script>

<template>
  <div>
    Hello World
  </div>
</template>

Server Middleware to Handle Cookie Headers

// ~/server/middleware/log.ts
export default defineEventHandler((event) => {
  const requestedURL = getRequestURL(event)
  if (requestedURL.pathname === '/api/test') {
    const cookieHeaders = getHeader(event, 'cookie')
    if (cookieHeaders) {
      const cookieArr = cookieHeaders.split(';').map((c) => c.trim()) // ensure to remove white spaces
      cookieArr.forEach((cookie) => {
        console.log(cookie)
      })
    }
  }
})

With this setup, when you make a request to the /api/test route, Nuxt will automatically include the cookie headers associated with the request in the request headers. This allows you to access cookie data in your server middleware.

Solution 2: Utilizing Object.assign() for Header Manipulation

To modify request headers effectively using server middleware, you can leverage the Object.assign() method. Here’s how you can achieve this:

// /server/middleware/auth.js
export default defineEventHandler((event) => {
  Object.assign(event.node.req.headers, { Authorization: 'Bearer test' });
});

By utilizing Object.assign(), you can merge the existing headers with the new Authorization header. This ensures that the modified headers are reflected accurately in the request.

The Object.assign() method takes two or more objects as arguments and assigns the properties of the latter object(s) to the first object. In this case, the first argument is the existing event.node.req.headers object, and the second argument is an object containing the Authorization header with the desired value.

This approach is efficient as it directly modifies the event.node.req.headers object, eliminating the need for additional assignments or property manipulation.

Video Explanation: