I retrieved the sitemap file in xml dynamically from a url. I created a special view to display the contents of the file. In this page, I'm using axios to call the url and fetch the content.

First I've created an axios plugin

export default function ({ $axios, error: nuxtError }, inject) {
  // Create a custom axios instance
  const xml = $axios.create({
    headers: {
      common: {
        'Content-Type': 'application/xml',
        'Accept': 'application/xml'
      }
    }
  })
  // If there is an error, this part of code will catch it and it will be handled by nuxt
  xml.onError((error) => {
    nuxtError({
      statusCode: error.response ? error.response.code : error.status,
      message: error.message
    })
    return Promise.resolve(error)
  })

  // Inject to context as $xml
  inject('xml', xml)
}

Then a sample vue page with an asyncData method

async asyncData({ $xml,$loader }: any) {
    // Initiate XML file content
    let xml!: string
    // Getting location sitemap's data
    const sitemap: any = await $loader.getSiteMap()
    if (sitemap?.resources) 
      // Get the xml file content
      xml = await $xml.$get(sitemap.resources.secure_url)
    return {
      xml
    }
  }

<template>
  <div>
    <pre>{{ xml }}</pre>
  </div>
</template>

The content is retrieved as a character string and not as an xml file. this is normal because when I check the content-type in my browser I find that it is text/html.

In the response detail got from axios, the content is clearly xml and not string

 headers: {
    connection: 'keep-alive',
    'content-length': '2233',
    'content-disposition': 'attachment; filename="sitemap.xml"',
    'content-type': 'application/xml',
    etag: 'W/"effe5154abe7b53448d1f0b170119529"',
    'last-modified': 'Wed, 19 Jan 2022 16:23:03 GMT',
    date: 'Thu, 20 Jan 2022 11:03:30 GMT',
    vary: 'Accept-Encoding',
    'strict-transport-security': 'max-age=604800',
    'cache-control': 'public, no-transform, immutable, max-age=2592000',
    'server-timing': 'fastly;dur=2;cpu=1;start=2022-01-20T11:03:30.276Z;desc=hit,rtt;dur=17',
    server: 'Cloudinary',
    'timing-allow-origin': '*',
    'access-control-allow-origin': '*',
    'accept-ranges': 'bytes',
    'access-control-expose-headers': 'Content-Length,Content-Disposition,ETag,Server-Timing,Vary'
  }

I don't know how I can force to change the content-type of only this page or find a way to better interpret the xml file