node_exporter/collector/gmond_collector.go
2014-06-26 21:16:21 +02:00

111 lines
2.5 KiB
Go

// +build ganglia
package collector
import (
"bufio"
"encoding/xml"
"fmt"
"io"
"net"
"regexp"
"time"
"github.com/golang/glog"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/node_exporter/collector/ganglia"
)
const (
gangliaAddress = "127.0.0.1:8649"
gangliaProto = "tcp"
gangliaTimeout = 30 * time.Second
gangliaMetricsPrefix = "ganglia_"
)
type gmondCollector struct {
Metrics map[string]*prometheus.GaugeVec
config Config
}
func init() {
Factories["gmond"] = NewGmondCollector
}
var illegalCharsRE = regexp.MustCompile(`[^a-zA-Z0-9_]`)
// Takes a config struct and prometheus registry and returns a new Collector scraping ganglia.
func NewGmondCollector(config Config) (Collector, error) {
c := gmondCollector{
config: config,
Metrics: map[string]*prometheus.GaugeVec{},
}
return &c, nil
}
func (c *gmondCollector) setMetric(name, cluster string, metric ganglia.Metric) {
if _, ok := c.Metrics[name]; !ok {
var desc string
var title string
for _, element := range metric.ExtraData.ExtraElements {
switch element.Name {
case "DESC":
desc = element.Val
case "TITLE":
title = element.Val
}
if title != "" && desc != "" {
break
}
}
glog.V(1).Infof("Register %s: %s", name, desc)
gv := prometheus.NewGaugeVec(
prometheus.GaugeOpts{
Namespace: gangliaMetricsPrefix,
Name: name,
Help: desc,
},
[]string{"cluster"},
)
c.Metrics[name] = prometheus.MustRegisterOrGet(gv).(*prometheus.GaugeVec)
}
glog.V(1).Infof("Set %s{cluster=%q}: %f", name, cluster, metric.Value)
c.Metrics[name].WithLabelValues(cluster).Set(metric.Value)
}
func (c *gmondCollector) Update() (updates int, err error) {
conn, err := net.Dial(gangliaProto, gangliaAddress)
glog.V(1).Infof("gmondCollector Update")
if err != nil {
return updates, fmt.Errorf("Can't connect to gmond: %s", err)
}
conn.SetDeadline(time.Now().Add(gangliaTimeout))
ganglia := ganglia.Ganglia{}
decoder := xml.NewDecoder(bufio.NewReader(conn))
decoder.CharsetReader = toUtf8
err = decoder.Decode(&ganglia)
if err != nil {
return updates, fmt.Errorf("Couldn't parse xml: %s", err)
}
for _, cluster := range ganglia.Clusters {
for _, host := range cluster.Hosts {
for _, metric := range host.Metrics {
name := illegalCharsRE.ReplaceAllString(metric.Name, "_")
c.setMetric(name, cluster.Name, metric)
updates++
}
}
}
return updates, err
}
func toUtf8(charset string, input io.Reader) (io.Reader, error) {
return input, nil //FIXME
}