为 golang prometheus 收集器添加标签

Question

我想弄清楚如何向普罗米修斯收集器添加标签。任何想法我在这里缺少什么？我有两个文件：main.go 和 collector.go我使用以下链接作为指南。https://rsmitty.github.io/Prometheus-Exporters/我模拟了这个例子，所以我可以把它贴在这里。我最终不会为命令提取“date +%s”。只是不知道在哪里添加标签。对于我正在尝试添加主机名的标签，结果如下：# HELP cmd_result Shows the cmd result# TYPE cmd_result gaugecmd_result{host="my_device_hostname"} 1.919256141363144e-76我对 golang 也很陌生，所以我很有可能把这一切都弄错了！我最终试图让普罗米修斯在每次刮擦时拉出 cmd 结果。主程序package mainimport (    "net/http"    log "github.com/Sirupsen/logrus"    "github.com/prometheus/client_golang/prometheus"    "github.com/prometheus/client_golang/prometheus/promhttp")func main() {    //Create a new instance of the collector and    //register it with the prometheus client.    cmd := newCollector()    prometheus.MustRegister(cmd)    //This section will start the HTTP server and expose    //any metrics on the /metrics endpoint.    http.Handle("/metrics", promhttp.Handler())    log.Info("Beginning to serve on port :8080")    log.Fatal(http.ListenAndServe(":8080", nil))}收集器.gopackage mainimport (    "encoding/binary"    "fmt"    "math"    "os/exec"    "strings"    "github.com/prometheus/client_golang/prometheus")type cmdCollector struct {    cmdMetric *prometheus.Desc}func newCollector() *cmdCollector {    return &cmdCollector{        cmdMetric: prometheus.NewDesc("cmd_result",            "Shows the cmd result",            nil, nil,        ),    }}func (collector *cmdCollector) Describe(ch chan<- *prometheus.Desc) {    ch <- collector.cmdMetric}func (collector *cmdCollector) Collect(ch chan<- prometheus.Metric) {    var metricValue float64    command := string("date +%s")    cmdResult := exeCmd(command)    metricValue = cmdResult    ch <- prometheus.MustNewConstMetric(collector.cmdMetric, prometheus.GaugeValue, metricValue)}

Answer 1

我想到了。我必须在调用 NewDesc 方法的地方声明标签，然后在 MustNewConstMetric 方法中传递值

这是带有“主机名”标签的新“newCollector”。

func newCollector() *cmdCollector {

    return &cmdCollector{

        cmdMetric: prometheus.NewDesc("cmd_result",

            "Shows the cmd result",

            []string{"hostname"}, nil,

        ),

    }

}

值得注意的是，我只是在这里添加“变量标签”。最后一个 'nil' 用于常量标签。

您可以像这样添加任意数量的项目...

[]string{"hostname", "another_label", "and_another_label"}

这在此处介绍： https ://godoc.org/github.com/prometheus/client_golang/prometheus#NewDesc

接下来，我可以在调用“MustNewConstMetric”方法时添加这些值。

ch <- prometheus.MustNewConstMetric(collector.cmdMetric, prometheus.GaugeValue, metricValue, hostname)

整个街区...

func (collector *cmdCollector) Collect(ch chan<- prometheus.Metric) {

    var metricValue float64

    command := string("date +%s")

    cmdResult := exeCmd(command)

    metricValue = cmdResult

    ch <- prometheus.MustNewConstMetric(collector.cmdMetric, prometheus.GaugeValue, metricValue, hostname)

}

如果我传入多个标签；比如我上面的例子，它看起来更像这样......

ch <- prometheus.MustNewConstMetric(collector.cmdMetric, prometheus.GaugeValue, metricValue, hostname, anotherLabel", "andAnotherLabel)