Divide stats collector in sub-collectors.

In order to avoid timeouts in case of many clients, it should be possible to configure which stats should be collected. Implements the following sub-collectors: * topics * channels * clients
2015-12-21 18:13:03 +01:00
parent 37b0428070
commit 470c5a0ae2
6 changed files with 242 additions and 196 deletions
--- a/main.go
+++ b/main.go
@@ -3,14 +3,14 @@ package main
 import (
 	"flag"
 	"fmt"
+	"log"
 	"net/http"
 	"net/url"
 	"strings"

-	"github.com/lovoo/nsq_exporter/collector"
+	"github.com/tsne/nsq_exporter/collector"

 	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/common/log"
 )

 // Version of nsq_exporter. Set at build time.
@@ -19,12 +19,19 @@ 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.")
-	nsqUrl            = flag.String("nsq.addr", "http://localhost:4151/stats", "Address of the NSQ host.")
-	enabledCollectors = flag.String("collectors", "nsqstats", "Comma-separated list of collectors to use.")
+	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(name string, x *collector.NsqExecutor) error{
-		"nsqstats": addStatsCollector,
+	collectorRegistry = map[string]func(names []string) (collector.Collector, error){
+		"stats": createNsqdStats,
+	}
+
+	// stats.* collectors
+	statsRegistry = map[string]func(namespace string) collector.StatsCollector{
+		"topics":   collector.TopicsCollector,
+		"channels": collector.ChannelsCollector,
+		"clients":  collector.ClientsCollector,
 	}
 )

@@ -37,11 +44,8 @@ func main() {
 	}
 	prometheus.MustRegister(ex)

-	handler := prometheus.Handler()
-	if *metricsPath == "" || *metricsPath == "/" {
-		http.Handle(*metricsPath, handler)
-	} else {
-		http.Handle(*metricsPath, handler)
+	http.Handle(*metricsPath, prometheus.Handler())
+	if *metricsPath != "" && *metricsPath != "/" {
 		http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
 			w.Write([]byte(`<html>
 			<head><title>NSQ Exporter</title></head>
@@ -53,6 +57,7 @@ func main() {
 		})
 	}

+	log.Print("listening to ", *listenAddress)
 	err = http.ListenAndServe(*listenAddress, nil)
 	if err != nil {
 		log.Fatal(err)
@@ -60,41 +65,62 @@ func main() {
 }

 func createNsqExecutor() (*collector.NsqExecutor, error) {
-	ex := collector.NewNsqExecutor(*namespace)
+	collectors := make(map[string][]string)
 	for _, name := range strings.Split(*enabledCollectors, ",") {
 		name = strings.TrimSpace(name)
-		addCollector, has := collectorRegistry[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("unknown collector: %s", name)
+			return nil, fmt.Errorf("invalid collector: %s", collector)
 		}

-		if err := addCollector(name, ex); err != nil {
+		c, err := newCollector(subcollectors)
+		if err != nil {
 			return nil, err
 		}
+		ex.AddCollector(collector, c)
 	}
 	return ex, nil
 }

-func addStatsCollector(name string, ex *collector.NsqExecutor) error {
-	u, err := url.Parse(normalizeURL(*nsqUrl))
+func createNsqdStats(statsCollectors []string) (collector.Collector, error) {
+	nsqdURL, err := normalizeURL(*nsqdURL)
 	if err != nil {
-		return err
+		return nil, err
 	}
-	if u.Scheme == "" {
-		u.Scheme = "http"
+
+	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"
-	ex.AddCollector(name, collector.NewStatsCollector(u.String()))
-	return nil
-}
-
-func normalizeURL(u string) string {
-	u = strings.ToLower(u)
-	if !strings.HasPrefix(u, "https://") && !strings.HasPrefix(u, "http://") {
-		return "http://" + u
-	}
-	return u
+	return u.String(), nil
 }