lib/limiter/PolicyLimiter.js
function(req, res, next) {
    var selector = this.selector.key(req)
    if (this.policy.allow(req, res, selector)) {
      next()
    } else {
      this.sendUnavailable(res, next)
    }
  }
function(req, res, next) {
    var selector = this.selector.key(req)
    if (this.policy.allow(req, res, selector)) {
      next()
    } else {
      this.sendUnavailable(res, next)
    }
  }
********************************************************************
@inheritdoc