glucose_exporter/httpslog/httpslog.go
2024-03-20 07:58:17 +00:00

60 lines
1.2 KiB
Go

package httpslog
import (
"fmt"
"log/slog"
"net/http"
"time"
"github.com/VictoriaMetrics/metrics"
"go.xsfx.dev/glucose_exporter/httpslog/internal/mutil"
)
func Handler() func(next http.Handler) http.Handler {
return func(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
start := time.Now()
lw := mutil.WrapWriter(w)
defer func() {
// Logging.
slog.Info(
"handled request",
"status",
lw.Status(),
"bytes",
lw.BytesWritten(),
"duration",
time.Since(start),
"method",
r.Method,
"url",
r.URL,
"user-agent",
r.UserAgent(),
"proto",
r.Proto,
)
// Metrics.
labels := fmt.Sprintf(
`method="%s",url="%s",status="%d"`,
r.Method,
r.URL,
lw.Status(),
)
metrics.GetOrCreateCounter(fmt.Sprintf(`requests_total{%s}`, labels)).Inc()
metrics.GetOrCreateSummary(
fmt.Sprintf(`requests_duration_seconds{%s}`, labels),
).UpdateDuration(start)
metrics.GetOrCreateHistogram(
fmt.Sprintf("response_size{%s}", labels),
).Update(float64(lw.BytesWritten()))
}()
next.ServeHTTP(lw, r)
})
}
}