initial commit

stats/vnstat.go

@@ -0,0 +1,86 @@
+package stats
+
+import (
+	"fmt"
+	"os/exec"
+
+	"github.com/go-errors/errors"
+	"github.com/goccy/go-json"
+)
+
+const (
+	vnstatBin = "/usr/bin/vnstat"
+)
+
+type VnstatTrafficRecord struct {
+	Date struct {
+		Year  uint `json:"year"`
+		Month uint `json:"month"`
+		Day   uint `json:"day"`
+	} `json:"date"`
+	Time struct {
+		Hour   uint `json:"hour"`
+		Minute uint `json:"minute"`
+	} `json:"time"`
+	Rx uint64 `json:"rx"`
+	Tx uint64 `json:"tx"`
+}
+
+type vnstatResponse struct {
+	Interfaces []struct {
+		Name    string `json:"name"`
+		Traffic struct {
+			FiveMinute []VnstatTrafficRecord `json:"fiveminute"`
+			Hour       []VnstatTrafficRecord `json:"hour"`
+			Day        []VnstatTrafficRecord `json:"day"`
+			Month      []VnstatTrafficRecord `json:"month"`
+		} `json:"traffic"`
+	} `json:"interfaces"`
+}
+
+func VnstatMonthlyTraffic(ifname string) ([]VnstatTrafficRecord, error) {
+	resp, err := callVnstat("--json", "m")
+	if err != nil {
+		return nil, errors.WrapPrefix(err, "failed to run vnstat", 0)
+	}
+
+	for _, iface := range resp.Interfaces {
+		if iface.Name == ifname {
+			return iface.Traffic.Month, nil
+		}
+	}
+
+	return nil, errors.New(fmt.Sprintf("interface %s not found", ifname))
+}
+
+func VnstatDailyTraffic(ifname string) ([]VnstatTrafficRecord, error) {
+	resp, err := callVnstat("--json", "d")
+	if err != nil {
+		return nil, errors.WrapPrefix(err, "failed to run vnstat", 0)
+	}
+
+	for _, iface := range resp.Interfaces {
+		if iface.Name == ifname {
+			return iface.Traffic.Day, nil
+		}
+	}
+
+	return nil, errors.New(fmt.Sprintf("interface %s not found", ifname))
+}
+
+func callVnstat(args ...string) (*vnstatResponse, error) {
+	cmd := exec.Command(vnstatBin, args...)
+	cmd.Stdin = nil
+	output, err := cmd.Output()
+
+	if err != nil {
+		return nil, err
+	}
+
+	var resp vnstatResponse
+	err = json.Unmarshal(output, &resp)
+	if err != nil {
+		return nil, errors.Wrap(err, 0)
+	}
+	return &resp, nil
+}