Set GEO location visitor country as a cookie with Netlify Edge functions

country-code.js

export default async (request, context) => {
  const countryCode = context.geo?.country?.code
  const url = new URL(request.url)

  if (!context.cookies.get('country')) {
    context.cookies.set({
      name: 'country',
      value: countryCode,
      path: '/',
      secure: true,
      sameSite: 'none',
      expires: new Date(Date.now() + 7 * 24 * 60 * 60 * 1000), // set cookie to expire in 7 days (1 week)
    })
  }

  return context.rewrite(url)
}

netlify.toml

[[edge_functions]]
  function = "country-code"
  path = "/*"