Function usePermanentRedirect

middleware/redirects/handle-redirects.js:170–187

(req)

}

function usePermanentRedirect(req) {
  // If the redirect was to essentially swap `enterprise-server@latest`
  // for `enterprise-server@3.x` then, we definitely don't want to
  // do a permanent redirect.
  // When this is the case, we don't want a permanent redirect because
  // it could overzealously cache in the users' browser which could
  // be bad when whatever "latest" means changes.
  if (req.path.includes('/enterprise-server@latest')) return false

  // If the redirect involved injecting a language prefix, then don't
  // permanently redirect because that could overly cache in users'
  // browsers if we some day want to make the language redirect
  // depend on a cookie or 'Accept-Language' header.
  if (pathLanguagePrefixed(req.path)) return true

  // The default is to *not* do a permanent redirect.
  return false
}

function removeQueryParams(redirect) {
  return new URL(redirect, 'https://docs.github.com').pathname