Introduction

The framework includes built-in Go basic metrics, which are disabled by default and need to be manually enabled. This can be done by enabling otelmetric.WithBuiltInMetrics() when creating the Provider.

package main

import (
    "go.opentelemetry.io/otel/exporters/prometheus"

    "github.com/gogf/gf/contrib/metric/otelmetric/v2"
    "github.com/gogf/gf/v2/frame/g"
    "github.com/gogf/gf/v2/os/gctx"
    "github.com/gogf/gf/v2/os/gmetric"
)

const (
    instrument        = "github.com/gogf/gf/example/metric/basic"
    instrumentVersion = "v1.0"
)

var (
    meter = gmetric.GetGlobalProvider().Meter(gmetric.MeterOption{
        Instrument:        instrument,
        InstrumentVersion: instrumentVersion,
    })
    counter = meter.MustCounter(
        "goframe.metric.demo.counter",
        gmetric.MetricOption{
            Help: "This is a simple demo for Counter usage",
            Unit: "bytes",
        },
    )
)

func main() {
    var ctx = gctx.New()

    // Prometheus exporter to export metrics as Prometheus format.
    exporter, err := prometheus.New(
        prometheus.WithoutCounterSuffixes(),
        prometheus.WithoutUnits(),
    )
    if err != nil {
        g.Log().Fatal(ctx, err)
    }

    // OpenTelemetry provider.
    provider := otelmetric.MustProvider(
        otelmetric.WithReader(exporter),
        otelmetric.WithBuiltInMetrics(),
    )
    provider.SetAsGlobal()
    defer provider.Shutdown(ctx)

    // Counter.
    counter.Inc(ctx)
    counter.Add(ctx, 10)

    // HTTP Server for metrics exporting.
    otelmetric.StartPrometheusMetricsServer(8000, "/metrics")
}

After execution, visit http://127.0.0.1:8000/metrics to view the results.

Built-in Metrics Description

Metric Name	Metric Type	Metric Unit	Metric Description
process.runtime.go.cgo.calls	Counter		Number of cgo calls in the current process.
process.runtime.go.gc.count	Counter		Number of completed gc cycles.
process.runtime.go.gc.pause_ns	Histogram	ns	Number of nanoseconds paused in GC stop-the-world .
process.runtime.go.gc.pause_total_ns	Counter	ns	Cumulative microseconds count of GC stop-the-world since the program started.
process.runtime.go.goroutines	Gauge		Number of currently running goroutines.
process.runtime.go.lookups	Counter		Number of pointer lookups executed at runtime.
process.runtime.go.mem.heap_alloc	Gauge	bytes	Number of bytes allocated to heap objects.
process.runtime.go.mem.heap_idle	Gauge	bytes	Idle (unused) heap memory.
process.runtime.go.mem.heap_inuse	Gauge	bytes	Heap memory in use.
process.runtime.go.mem.heap_objects	Gauge		Number of heap objects allocated.
process.runtime.go.mem.live_objects	Gauge		Number of live objects (Mallocs - Frees).
process.runtime.go.mem.heap_released	Gauge	bytes	Heap memory returned to the operating system.
process.runtime.go.mem.heap_sys	Gauge	bytes	Heap memory obtained from the operating system.
process.runtime.uptime	Counter	ms	Number of milliseconds since the application was initialized.