Fantom-foundation/go-lachesis

package metrics

import (
    "os"
    "path/filepath"
    "sync/atomic"

    "github.com/ethereum/go-ethereum/log"
    "github.com/ethereum/go-ethereum/metrics"
    cli "gopkg.in/urfave/cli.v1"

    "github.com/Fantom-foundation/go-lachesis/metrics/prometheus"
)

var PrometheusEndpointFlag = cli.StringFlag{
    Name:  "metrics.prometheus.endpoint",
    Usage: "Prometheus API endpoint to report metrics to",
    Value: ":19090",
}

func SetupPrometheus(ctx *cli.Context) {
    if !metrics.Enabled {
        return
    }
    prometheus.SetNamespace("lachesis")
    var endpoint = ctx.GlobalString(PrometheusEndpointFlag.Name)
    prometheus.ListenTo(endpoint, nil)
}

var (
    // TODO: refactor it
    dbDir        atomic.Value
    dbSizeMetric = metrics.NewRegisteredFunctionalGauge("db_size", nil, measureDbDir)
)

func SetDataDir(datadir string) {
    dbDir.Store(datadir)
}

func measureDbDir() (size int64) {
    datadir, ok := dbDir.Load().(string)
    if !ok || datadir == "" || datadir == "inmemory" {
        return
    }

    err := filepath.Walk(datadir, func(_ string, info os.FileInfo, err error) error {
        if err != nil {
            return err
        }
        if !info.IsDir() {
            size += info.Size()
        }
        return err
    })
    if err != nil {
        log.Error("filepath.Walk", "path", datadir, "err", err)
        return 0
    }

    return
}