package main

//自己动手编写一个Exporter
//一般来说，绝大多数Exporter都是基于Go语言编写的，一小部分是基于Python语言编写的，还有很小一部分是使用Java语言编写的。比如官方提供的Consul Metrics自定义采集器Exporter，如果是在Go语言的运行环境下，需要按照如下所示代码运行这个Exporter。

import (
	"log"
	"net/http"

	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/client_golang/prometheus/promhttp"
)

var (
	cpuTemp = prometheus.NewGauge(prometheus.GaugeOpts{
		Namespace: "our_idc",
		Subsystem: "k8s",
		Name:      "cpu_temperature_celsius",
		Help:      "Current temperature of the CPU.",
	})
	hdFailures = prometheus.NewCounterVec(
		prometheus.CounterOpts{
			Namespace: "our_idc",
			Subsystem: "k8s",
			Name:      "hd_errors_total",
			Help:      "Number of hard-disk errors.",
		},
		[]string{"device"},
	)
)

func init() {
	// Metrics have to be registered to be exposed:
	prometheus.MustRegister(cpuTemp)
	prometheus.MustRegister(hdFailures)
}

func main() {
	cpuTemp.Set(65.3)
	hdFailures.With(prometheus.Labels{"device": "/dev/sda"}).Inc()

	// The Handler function provides a default handler to expose metrics
	// via an HTTP server. "/metrics" is the usual endpoint for that.
	http.Handle("/metrics", promhttp.Handler())
	log.Fatal(http.ListenAndServe(":9105", nil))

}