title: Token based authentication using nginx-ingress annotations
body: <p>I am trying to pass token as query parameter to ingress annotation auth-url to perform token validation. I need to extract token from URL similar to one mentioned below:</p>
  <p><a href="https://xx.xx.xx.xx/red/openapi/test?token=**12643AF7C4CF4DA4960AB23157405C40*" rel="nofollow noreferrer">https://xx.xx.xx.xx/red/openapi/test?token=**12643AF7C4CF4DA4960AB23157405C40*</a>*
  note: I cannot use Oauth2 to implement this use case.</p>
  <p>I need help to identify which annotation can be used to extract token from uri and pass it to variable $token</p>
  <p>apiVersion: extensions/v1beta1
  kind: Ingress
  metadata:
  annotations:
  kubernetes.io/ingress.class: nginx
  nginx.ingress.kubernetes.io/auth-response-headers: authorization
  nginx.ingress.kubernetes.io/auth-url: http://authorization-v2..svc.cluster.local:8080/authorization-v2/api/v1/validate?token=<strong>$token</strong></p>