prom2json-stream

prom2json-stream is a NodeJS stream transformer to parse Prometheus exporters' metrics into JSON

Example

# HELP go_memstats_alloc_bytes Number of bytes allocated and still in use.
# TYPE go_memstats_alloc_bytes gauge
go_memstats_alloc_bytes 2.787184e+06
# HELP promhttp_metric_handler_requests_total Total number of scrapes by HTTP status code.
# TYPE promhttp_metric_handler_requests_total counter
promhttp_metric_handler_requests_total{code="200"} 139170
promhttp_metric_handler_requests_total{code="500"} 0
promhttp_metric_handler_requests_total{code="503"} 0

transformed into

[  
  {  
    "help":"Number of bytes allocated and still in use.",
    "name":"go_memstats_alloc_bytes",
    "type":"gauge",
    "value":2787184
  },
  {  
    "help":"Total number of scrapes by HTTP status code.",
    "name":"promhttp_metric_handler_requests_total",
    "type":"counter",
    "value":139170,
    "labels":{  
      "code":"200"
    }
  },
  {  
    "help":"Total number of scrapes by HTTP status code.",
    "name":"promhttp_metric_handler_requests_total",
    "type":"counter",
    "value":0,
    "labels":{  
      "code":"500"
    }
  },
  {  
    "help":"Total number of scrapes by HTTP status code.",
    "name":"promhttp_metric_handler_requests_total",
    "type":"counter",
    "value":0,
    "labels":{  
      "code":"503"
    }
  }
]

Installation

Using NPM

npm install prom2json-stream

Usage

From a readable stream

var Prom2Json = require('prom2json-stream')
var split = require('binary-split')
 
var buffer = `
# HELP go_memstats_alloc_bytes Number of bytes allocated and still in use.
# TYPE go_memstats_alloc_bytes gauge
go_memstats_alloc_bytes 2.787184e+06
`
var stream = new Readable()
stream.push(buffer)
stream.push(null)
 
stream
  .pipe(split())
  .pipe(Prom2Json())
  .on('data', function (data) {
    console.log(data)
  })
// {
//    "help": "Number of bytes allocated and still in use.",
//    "name": "go_memstats_alloc_bytes",
//    "type": "gauge",
//    "value": 2787184
//  }

Caveats

This library only accepting string/buffer that has been splitted by newline. Please consider using any working splitter (eg: binary-split