in pan-domain-auth-play/src/main/scala/com/gu/pandomainauth/action/Actions.scala [224:228]
def extractAuth(request: RequestHeader): AuthenticationStatus = {
readCookie(request).map { cookie =>
PanDomain.authStatus(cookie.cookie.value, settings.signingAndVerification, validateUser, system, cacheValidation, cookie.forceExpiry)
} getOrElse NotAuthenticated
}