netlify-cli/functions-templates/javascript/transform-response/{{name}}.js

Netlify command line tool

export default async (request, context) => {
  const url = new URL(request.url)

  // Look for the query parameter, and return if we don't find it
  if (url.searchParams.get('method') !== 'transform') {
    return
  }

  const response = await context.next()
  const text = await response.text()
  return new Response(text.toUpperCase(), response)
}