go-pkg/lg/metric.go
2023-07-12 12:43:25 -06:00

98 lines
2.3 KiB
Go

package lg
import (
"context"
"log"
"net/http"
"time"
"github.com/prometheus/client_golang/prometheus/promhttp"
"go.opentelemetry.io/contrib/instrumentation/runtime"
"go.opentelemetry.io/otel"
"go.opentelemetry.io/otel/exporters/prometheus"
api "go.opentelemetry.io/otel/metric"
sdk "go.opentelemetry.io/otel/sdk/metric"
)
var meterKey = contextKey{"meter"}
var promHTTPKey = contextKey{"promHTTP"}
func Meter(ctx context.Context) api.Meter {
if t := fromContext[contextKey, api.Meter](ctx, tracerKey); t != nil {
return t
}
return otel.Meter("")
}
func NewHTTP(ctx context.Context) *httpHandle {
t := fromContext[contextKey, *prometheus.Exporter](ctx, promHTTPKey)
return &httpHandle{t}
}
func initMetrics(ctx context.Context, name string) (context.Context, func() error) {
// goversion := ""
// pkg := ""
// host := ""
// if info, ok := debug.ReadBuildInfo(); ok {
// goversion = info.GoVersion
// pkg = info.Path
// }
// if h, err := os.Hostname(); err == nil {
// host = h
// }
// config := prometheus.Config{
// DefaultHistogramBoundaries: []float64{
// 2 << 6, 2 << 8, 2 << 10, 2 << 12, 2 << 14, 2 << 16, 2 << 18, 2 << 20, 2 << 22, 2 << 24, 2 << 26, 2 << 28,
// },
// }
// cont := controller.New(
// processor.NewFactory(
// selector.NewWithHistogramDistribution(
// histogram.WithExplicitBoundaries(config.DefaultHistogramBoundaries),
// ),
// aggregation.CumulativeTemporalitySelector(),
// processor.WithMemory(true),
// ),
// controller.WithResource(
// resource.NewWithAttributes(
// semconv.SchemaURL,
// attribute.String("app", name),
// attribute.String("host", host),
// attribute.String("go_version", goversion),
// attribute.String("pkg", pkg),
// ),
// ),
// )
ex, err := prometheus.New()
if err != nil {
return ctx, nil
}
provider := sdk.NewMeterProvider(sdk.WithReader(ex))
meter := provider.Meter(name)
ctx = toContext(ctx, promHTTPKey, ex)
ctx = toContext(ctx, meterKey, meter)
runtime.Start()
return ctx, func() error {
_, cancel := context.WithTimeout(context.Background(), 1*time.Second)
defer cancel()
defer log.Println("metrics stopped")
return nil
}
}
type httpHandle struct {
exp *prometheus.Exporter
}
func (h *httpHandle) RegisterHTTP(mux *http.ServeMux) {
if h.exp == nil {
return
}
mux.Handle("/metrics", promhttp.Handler())
}