package metrics provides a set of uniform interfaces for service instrumentation.
It has counters, gauges, and histograms,
and provides adapters to popular metrics packages, like expvar, statsd, and Prometheus.
TODO
A simple counter, exported via expvar.
import "github.com/go-kit/kit/metrics/expvar"
func main() {
myCount := expvar.NewCounter("my_count")
myCount.Add(1)
}A histogram for request duration, exported via a Prometheus summary with dynamically-computed quantiles.
import (
stdprometheus "github.com/prometheus/client_golang/prometheus"
"github.com/go-kit/kit/metrics"
"github.com/go-kit/kit/metrics/prometheus"
)
var requestDuration = prometheus.NewSummary(stdprometheus.SummaryOpts{
Namespace: "myservice",
Subsystem: "api",
Name: "request_duration_nanoseconds_count",
Help: "Total time spent serving requests.",
}, []string{})
func handleRequest() {
defer func(begin time.Time) { requestDuration.Observe(time.Since(begin)) }(time.Now())
// handle request
}A gauge for the number of goroutines currently running, exported via statsd.
import (
"net"
"os"
"runtime"
"time"
"github.com/go-kit/kit/metrics/statsd"
)
func main() {
statsdWriter, err := net.Dial("udp", "127.0.0.1:8126")
if err != nil {
os.Exit(1)
}
reportingDuration := 5 * time.Second
goroutines := statsd.NewGauge(statsdWriter, "total_goroutines", reportingDuration)
for range time.Tick(reportingDuration) {
goroutines.Set(float64(runtime.NumGoroutine()))
}
}