node_exporter/exporter/gmond_collector.go

105 lines
2.5 KiB
Go

package exporter
import (
"bufio"
"encoding/xml"
"fmt"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/node_exporter/exporter/ganglia"
"io"
"net"
"regexp"
"time"
)
const (
gangliaAddress = "127.0.0.1:8649"
gangliaProto = "tcp"
gangliaTimeout = 30 * time.Second
)
type gmondCollector struct {
name string
Metrics map[string]prometheus.Gauge
config config
registry prometheus.Registry
}
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, registry prometheus.Registry) (collector gmondCollector, err error) {
collector = gmondCollector{
name: "gmond_collector",
config: config,
Metrics: make(map[string]prometheus.Gauge),
registry: registry,
}
return collector, nil
}
func (c *gmondCollector) Name() string { return c.name }
func (c *gmondCollector) setMetric(name string, labels map[string]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
}
}
debug(c.Name(), "Register %s: %s", name, desc)
gauge := prometheus.NewGauge()
c.Metrics[name] = gauge
c.registry.Register(name, desc, prometheus.NilLabels, gauge) // one gauge per metric!
}
debug(c.Name(), "Set %s{%s}: %f", name, labels, metric.Value)
c.Metrics[name].Set(labels, metric.Value)
}
func (c *gmondCollector) Update() (updates int, err error) {
conn, err := net.Dial(gangliaProto, gangliaAddress)
debug(c.Name(), "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, "_")
var labels = map[string]string{
"cluster": cluster.Name,
}
c.setMetric(name, labels, metric)
updates++
}
}
}
return updates, err
}
func toUtf8(charset string, input io.Reader) (io.Reader, error) {
return input, nil //FIXME
}