prometheus 自己實現exporter

1.  看源代碼可以發現Collector 接口定義了兩個方法，實現這兩個方法就可以暴露數據了。

 

 

2. 示列代碼

package main

import (
   "net/http"
   "github.com/prometheus/client_golang/prometheus/promhttp"
   "github.com/prometheus/common/log"
   "github.com/prometheus/client_golang/prometheus"
)

type fooCollector struct {
   fooMetric *prometheus.Desc
   barMetric *prometheus.Desc
}


func newFooCollector() *fooCollector {
   m1 := make(map[string]string)
   m1["env"] = "prod"
   v := []string{"hostname"}
   return &fooCollector{
      fooMetric: prometheus.NewDesc("fff_metrics","Show metrics a for mysql",nil,nil),
      barMetric:prometheus.NewDesc("bbb_metrics","Show metrics a bar occu",v,m1),
   }
}

func (collect *fooCollector) Describe(ch chan <- *prometheus.Desc) {
   ch <- collect.barMetric
   ch <- collect.fooMetric

}

func (collect *fooCollector) Collect(ch chan<- prometheus.Metric) {
   var metricValue float64

   if 1 == 1 {
      metricValue = 1
   }


   ch <- prometheus.MustNewConstMetric(collect.fooMetric,prometheus.GaugeValue, metricValue)
   ch <- prometheus.MustNewConstMetric(collect.barMetric,prometheus.CounterValue, metricValue,"kk")
}


func main() {
   foo := newFooCollector()
   prometheus.MustRegister(foo)
   log.Info("beging to server on Port: 18080")
   http.Handle("/metrics",promhttp.Handler())
   log.Fatal(http.ListenAndServe(":18080",nil))
}


# 一個變量label， 一個是常量label.