package main
import (
"flag"
"fmt"
"log"
"net/http"
"net/url"
"strings"
"github.com/lovoo/nsq_exporter/collector"
"github.com/prometheus/client_golang/prometheus"
)
// Version of nsq_exporter. Set at build time.
const Version = "0.0.0.dev"
var (
listenAddress = flag.String("web.listen", ":9117", "Address on which to expose metrics and web interface.")
metricsPath = flag.String("web.path", "/metrics", "Path under which to expose metrics.")
nsqdURL = flag.String("nsqd.addr", "http://localhost:4151/stats", "Address of the nsqd node.")
enabledCollectors = flag.String("collect", "stats.topics,stats.channels", "Comma-separated list of collectors to use.")
namespace = flag.String("namespace", "nsq", "Namespace for the NSQ metrics.")
collectorRegistry = map[string]func(names []string) (collector.Collector, error){
"stats": createNsqdStats,
}
// stats.* collectors
statsRegistry = map[string]func(namespace string) collector.StatsCollector{
"topics": collector.TopicStats,
"channels": collector.ChannelStats,
"clients": collector.ClientStats,
}
)
func main() {
flag.Parse()
ex, err := createNsqExecutor()
if err != nil {
log.Fatalf("error creating nsq executor: %v", err)
}
prometheus.MustRegister(ex)
http.Handle(*metricsPath, prometheus.Handler())
if *metricsPath != "" && *metricsPath != "/" {
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte(`
NSQ Exporter
NSQ Exporter
Metrics
`))
})
}
log.Print("listening to ", *listenAddress)
err = http.ListenAndServe(*listenAddress, nil)
if err != nil {
log.Fatal(err)
}
}
func createNsqExecutor() (*collector.NsqExecutor, error) {
collectors := make(map[string][]string)
for _, name := range strings.Split(*enabledCollectors, ",") {
name = strings.TrimSpace(name)
parts := strings.SplitN(name, ".", 2)
if len(parts) != 2 {
return nil, fmt.Errorf("invalid collector name: %s", name)
}
collectors[parts[0]] = append(collectors[parts[0]], parts[1])
}
ex := collector.NewNsqExecutor(*namespace)
for collector, subcollectors := range collectors {
newCollector, has := collectorRegistry[collector]
if !has {
return nil, fmt.Errorf("invalid collector: %s", collector)
}
c, err := newCollector(subcollectors)
if err != nil {
return nil, err
}
ex.AddCollector(collector, c)
}
return ex, nil
}
func createNsqdStats(statsCollectors []string) (collector.Collector, error) {
nsqdURL, err := normalizeURL(*nsqdURL)
if err != nil {
return nil, err
}
stats := collector.NewNsqdStats(*namespace, nsqdURL)
for _, c := range statsCollectors {
newStatsCollector, has := statsRegistry[c]
if !has {
return nil, fmt.Errorf("unknown stats collector: %s", c)
}
stats.Use(newStatsCollector(*namespace))
}
return stats, nil
}
func normalizeURL(ustr string) (string, error) {
ustr = strings.ToLower(ustr)
if !strings.HasPrefix(ustr, "https://") && !strings.HasPrefix(ustr, "http://") {
ustr = "http://" + ustr
}
u, err := url.Parse(ustr)
if err != nil {
return "", err
}
if u.Path == "" {
u.Path = "/stats"
}
u.RawQuery = "format=json"
return u.String(), nil
}