Merge pull request #162 from dswarbrick/exporter-kit-flags

Modernize exporter-toolkit flag parsing

README.md

@@ -13,24 +13,29 @@ With working golang environment it can be built with `go get`.  There is a [good
 Help on flags:
 
 <pre>
-  -h, --help               Show context-sensitive help (also try --help-long and
-                           --help-man).
-      --telemetry.address=":9117"
-                           Address on which to expose metrics.
+  -h, --[no-]help                Show context-sensitive help (also try
+                                 --help-long and --help-man).
       --telemetry.endpoint="/metrics"
-                           Path under which to expose metrics.
-      --scrape_uri="http://localhost/server-status?auto"
-                           URI to apache stub status page.
-      --host_override=""   Override for HTTP Host header; empty string for no
-                           override.
-      --insecure           Ignore server certificate if using https.
+                                 Path under which to expose metrics.
+      --scrape_uri="http://localhost/server-status/?auto"
+                                 URI to apache stub status page.
+      --host_override=""         Override for HTTP Host header; empty string for
+                                 no override.
+      --[no-]insecure            Ignore server certificate if using https.
       --custom_headers     Adds custom headers to the collector.
-      --web.config=""      Path to config yaml file that can enable TLS or
-                           authentication.
-      --log.level=info     Only log messages with the given severity or above.
-                           One of: [debug, info, warn, error]
-      --log.format=logfmt  Output format of log messages. One of: [logfmt, json]
-      --version            Show application version.
+      --[no-]web.systemd-socket  Use systemd socket activation listeners instead
+                                 of port listeners (Linux only).
+      --web.listen-address=:9117 ...
+                                 Addresses on which to expose metrics and web
+                                 interface. Repeatable for multiple addresses.
+      --web.config.file=""       [EXPERIMENTAL] Path to configuration file that
+                                 can enable TLS or authentication.
+      --log.level=info           Only log messages with the given severity or
+                                 above. One of: [debug, info, warn, error]
+      --log.format=logfmt        Output format of log messages. One of: [logfmt,
+                                 json]
+      --[no-]version             Show application version.
+
 </pre>
 
 Tested on Apache 2.2 and Apache 2.4.

apache_exporter.go

@@ -10,7 +10,6 @@ package main
 import (
 	"net/http"
 	"os"
-
 	"os/signal"
 	"syscall"
 	"time"
@@ -24,21 +23,20 @@ import (
 	"github.com/prometheus/common/promlog/flag"
 	"github.com/prometheus/common/version"
 	"github.com/prometheus/exporter-toolkit/web"
+	"github.com/prometheus/exporter-toolkit/web/kingpinflag"
 )
 
 var (
-	listeningAddress = kingpin.Flag("telemetry.address", "Address on which to expose metrics.").Default(":9117").String()
-	metricsEndpoint  = kingpin.Flag("telemetry.endpoint", "Path under which to expose metrics.").Default("/metrics").String()
-	scrapeURI        = kingpin.Flag("scrape_uri", "URI to apache stub status page.").Default("http://localhost/server-status/?auto").String()
-	hostOverride     = kingpin.Flag("host_override", "Override for HTTP Host header; empty string for no override.").Default("").String()
-	insecure         = kingpin.Flag("insecure", "Ignore server certificate if using https.").Bool()
-	customHeaders    = kingpin.Flag("custom_headers", "Adds custom headers to the collector.").StringMap()
-	configFile       = kingpin.Flag("web.config", "Path to config yaml file that can enable TLS or authentication.").Default("").String()
-	gracefulStop     = make(chan os.Signal, 1)
+	metricsEndpoint = kingpin.Flag("telemetry.endpoint", "Path under which to expose metrics.").Default("/metrics").String()
+	scrapeURI       = kingpin.Flag("scrape_uri", "URI to apache stub status page.").Default("http://localhost/server-status/?auto").String()
+	hostOverride    = kingpin.Flag("host_override", "Override for HTTP Host header; empty string for no override.").Default("").String()
+	insecure        = kingpin.Flag("insecure", "Ignore server certificate if using https.").Bool()
+	toolkitFlags    = kingpinflag.AddFlags(kingpin.CommandLine, ":9117")
+	gracefulStop    = make(chan os.Signal, 1)
+	customHeaders   = kingpin.Flag("custom_headers", "Adds custom headers to the collector.").StringMap()
 )
 
 func main() {
-
 	promlogConfig := &promlog.Config{}
 
 	// Parse flags
@@ -60,20 +58,12 @@ func main() {
 		CustomHeaders: *customHeaders,
 	}
 
-	webSystemdSocket := false
-	webListenAddresses := []string{*listeningAddress}
-	flagConfig := &web.FlagConfig{
-		WebConfigFile:      configFile,
-		WebSystemdSocket:   &webSystemdSocket,
-		WebListenAddresses: &webListenAddresses,
-	}
 	exporter := collector.NewExporter(logger, config)
 	prometheus.MustRegister(exporter)
 	prometheus.MustRegister(version.NewCollector("apache_exporter"))
 
 	level.Info(logger).Log("msg", "Starting apache_exporter", "version", version.Info())
 	level.Info(logger).Log("msg", "Build context", "build", version.BuildContext())
-	level.Info(logger).Log("msg", "Starting Server: ", "listen_address", *listeningAddress)
 	level.Info(logger).Log("msg", "Collect from: ", "scrape_uri", *scrapeURI)
 
 	// listener for the termination signals from the OS
@@ -82,7 +72,6 @@ func main() {
 		sig := <-gracefulStop
 		level.Info(logger).Log("msg", "caught sig: %+v. Wait 2 seconds...", "sig", sig)
 		time.Sleep(2 * time.Second)
-		level.Info(logger).Log("msg", "Terminate apache-exporter on port:", "listen_address", *listeningAddress)
 		os.Exit(0)
 	}()
 
@@ -96,13 +85,10 @@ func main() {
 			 </body>
 			 </html>`))
 	})
-	//log.Fatal(http.ListenAndServe(*listeningAddress, nil))
 
-	server := &http.Server{Addr: *listeningAddress}
-
-	if err := web.ListenAndServe(server, flagConfig, logger); err != nil {
-		level.Error(logger).Log("msg", "Listening error", "reason", err)
+	server := &http.Server{}
+	if err := web.ListenAndServe(server, toolkitFlags, logger); err != nil {
+		level.Error(logger).Log("err", err)
 		os.Exit(1)
 	}
-
 }