Replicate only my alerting sensors.

alerting-temperatures.json

{
   "_id": "alerting-temperatures",
   "source": "temperature",
   "target": "temperature-alerting",
   "filter": "app/alerting",
   "query_params": {
       "ranges": {
           "1081841E000000DF": {
               "low": 4,
               "high": 31
           },
           "10C8892A00000096": {
               "low": 5,
               "high": 30
           },
           "101D8A2A000000F7": {
               "low": 5,
               "high": 27
           },
           "1013A51E00000035": {
               "low": 5,
               "high": 30
           }
       }
   }
}

alerting.coffee

(doc, req) ->
    if  (! (doc.type? == 'reading'))
        return true

    ranges = if typeof(req.query.ranges) == "string" then JSON.parse(req.query.ranges) else req.query.ranges

    if (!ranges)
        throw("Need the serial number alert levels in 'ranges' parameter.")

    if (! ranges[doc.sn])
        return false

    return (!(ranges[doc.sn].low < doc.reading < ranges[doc.sn].high))