Rename linux collectors for build constraints.

collector/interrupts_linux.go

@@ -0,0 +1,115 @@
+// +build !nointerrupts
+
+package collector
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+const (
+	procInterrupts = "/proc/interrupts"
+)
+
+type interruptsCollector struct {
+	metric *prometheus.CounterVec
+}
+
+func init() {
+	Factories["interrupts"] = NewInterruptsCollector
+}
+
+// Takes a prometheus registry and returns a new Collector exposing
+// interrupts stats
+func NewInterruptsCollector() (Collector, error) {
+	return &interruptsCollector{
+		metric: prometheus.NewCounterVec(
+			prometheus.CounterOpts{
+				Namespace: Namespace,
+				Name:      "interrupts",
+				Help:      "Interrupt details from /proc/interrupts.",
+			},
+			[]string{"CPU", "type", "info", "devices"},
+		),
+	}, nil
+}
+
+func (c *interruptsCollector) Update(ch chan<- prometheus.Metric) (err error) {
+	interrupts, err := getInterrupts()
+	if err != nil {
+		return fmt.Errorf("Couldn't get interrupts: %s", err)
+	}
+	for name, interrupt := range interrupts {
+		for cpuNo, value := range interrupt.values {
+			fv, err := strconv.ParseFloat(value, 64)
+			if err != nil {
+				return fmt.Errorf("Invalid value %s in interrupts: %s", value, err)
+			}
+			labels := prometheus.Labels{
+				"CPU":     strconv.Itoa(cpuNo),
+				"type":    name,
+				"info":    interrupt.info,
+				"devices": interrupt.devices,
+			}
+			c.metric.With(labels).Set(fv)
+		}
+	}
+	c.metric.Collect(ch)
+	return err
+}
+
+type interrupt struct {
+	info    string
+	devices string
+	values  []string
+}
+
+func getInterrupts() (map[string]interrupt, error) {
+	file, err := os.Open(procInterrupts)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	return parseInterrupts(file)
+}
+
+func parseInterrupts(r io.Reader) (map[string]interrupt, error) {
+	var (
+		interrupts = map[string]interrupt{}
+		scanner    = bufio.NewScanner(r)
+	)
+
+	if !scanner.Scan() {
+		return nil, fmt.Errorf("%s empty", procInterrupts)
+	}
+	cpuNum := len(strings.Fields(string(scanner.Text()))) // one header per cpu
+
+	for scanner.Scan() {
+		line := scanner.Text()
+		parts := strings.Fields(string(line))
+		if len(parts) < cpuNum+2 { // irq + one column per cpu + details,
+			continue // we ignore ERR and MIS for now
+		}
+		intName := parts[0][:len(parts[0])-1] // remove trailing :
+		intr := interrupt{
+			values: parts[1:cpuNum],
+		}
+
+		if _, err := strconv.Atoi(intName); err == nil { // numeral interrupt
+			intr.info = parts[cpuNum+1]
+			intr.devices = strings.Join(parts[cpuNum+2:], " ")
+		} else {
+			intr.info = strings.Join(parts[cpuNum+1:], " ")
+		}
+		interrupts[intName] = intr
+	}
+
+	return interrupts, nil
+}