rocket.chat.mqtt/node_modules/npm/lib/utils/is-registry.js

It's a MQTT Server, using redis to scale horizontally.

'use strict'
module.exports = isRegistry

function isRegistry (req) {
  if (req == null) return false
  // modern metadata
  if ('registry' in req) return req.registry
  // legacy metadata
  if (req.type === 'range' || req.type === 'version' || req.type === 'tag') return true
  return false
}