Rename linux collectors for build constraints.

collector/netstat_linux.go

@@ -0,0 +1,101 @@
+// +build !nonetstat
+
+package collector
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+const (
+	procNetStat       = "/proc/net/netstat"
+	netStatsSubsystem = "netstat"
+)
+
+type netStatCollector struct {
+	metrics map[string]prometheus.Gauge
+}
+
+func init() {
+	Factories["netstat"] = NewNetStatCollector
+}
+
+// NewNetStatCollector takes a returns
+// a new Collector exposing network stats.
+func NewNetStatCollector() (Collector, error) {
+	return &netStatCollector{
+		metrics: map[string]prometheus.Gauge{},
+	}, nil
+}
+
+func (c *netStatCollector) Update(ch chan<- prometheus.Metric) (err error) {
+	netStats, err := getNetStats()
+	if err != nil {
+		return fmt.Errorf("couldn't get netstats: %s", err)
+	}
+	for protocol, protocolStats := range netStats {
+		for name, value := range protocolStats {
+			key := protocol + "_" + name
+			if _, ok := c.metrics[key]; !ok {
+				c.metrics[key] = prometheus.NewGauge(
+					prometheus.GaugeOpts{
+						Namespace: Namespace,
+						Subsystem: netStatsSubsystem,
+						Name:      key,
+						Help:      fmt.Sprintf("%s %s from /proc/net/netstat.", protocol, name),
+					},
+				)
+			}
+			v, err := strconv.ParseFloat(value, 64)
+			if err != nil {
+				return fmt.Errorf("invalid value %s in netstats: %s", value, err)
+			}
+			c.metrics[key].Set(v)
+		}
+	}
+	for _, m := range c.metrics {
+		m.Collect(ch)
+	}
+	return err
+}
+
+func getNetStats() (map[string]map[string]string, error) {
+	file, err := os.Open(procNetStat)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	return parseNetStats(file)
+}
+
+func parseNetStats(r io.Reader) (map[string]map[string]string, error) {
+	var (
+		netStats = map[string]map[string]string{}
+		scanner  = bufio.NewScanner(r)
+	)
+
+	for scanner.Scan() {
+		nameParts := strings.Split(string(scanner.Text()), " ")
+		scanner.Scan()
+		valueParts := strings.Split(string(scanner.Text()), " ")
+		// Remove trailing :.
+		protocol := nameParts[0][:len(nameParts[0])-1]
+		netStats[protocol] = map[string]string{}
+		if len(nameParts) != len(valueParts) {
+			return nil, fmt.Errorf("mismatch field count mismatch in %s: %s",
+				procNetStat, protocol)
+		}
+		for i := 1; i < len(nameParts); i++ {
+			netStats[protocol][nameParts[i]] = valueParts[i]
+		}
+	}
+
+	return netStats, nil
+}