Make version informations consistent between prometheus components

This also fixes #231 by adding the '-version' flag

.promu.yml

@@ -3,10 +3,11 @@ repository:
     path: github.com/prometheus/node_exporter
 build:
     ldflags: |
-        -X main.Version={{.Version}}
-        -X {{repoPath}}/collector.Version={{.Version}}
-        -X {{repoPath}}/collector.Revision={{.Revision}}
-        -X {{repoPath}}/collector.Branch={{.Branch}}
+        -X {{repoPath}}/vendor/github.com/prometheus/common/version.Version={{.Version}}
+        -X {{repoPath}}/vendor/github.com/prometheus/common/version.Revision={{.Revision}}
+        -X {{repoPath}}/vendor/github.com/prometheus/common/version.Branch={{.Branch}}
+        -X {{repoPath}}/vendor/github.com/prometheus/common/version.BuildUser={{user}}@{{host}}
+        -X {{repoPath}}/vendor/github.com/prometheus/common/version.BuildDate={{date "20060102-15:04:05"}}
 tarball:
     files:
         - LICENSE

README.md

@@ -34,7 +34,6 @@ stat | Exposes various statistics from `/proc/stat`. This includes CPU usage, bo
 textfile | Exposes statistics read from local disk. The `--collector.textfile.directory` flag must be set. | _any_
 time | Exposes the current system time. | _any_
 vmstat | Exposes statistics from `/proc/vmstat`. | Linux
-version | Exposes node\_exporter version. | _any_
 
 
 ### Disabled by default

collector/fixtures/e2e-output.txt

@@ -365,6 +365,9 @@ node_disk_writes_merged{device="vda"} 2.0711856e+07
 # HELP node_entropy_available_bits Bits of available entropy.
 # TYPE node_entropy_available_bits gauge
 node_entropy_available_bits 1337
+# HELP node_exporter_build_info A metric with a constant '1' value labeled by version, revision, branch, and goversion from which node_exporter was built.
+# TYPE node_exporter_build_info gauge
+node_exporter_build_info{branch="master",goversion="go1.5.4",revision="252feb6",version="0.12.0rc3"} 1
 # HELP node_exporter_scrape_duration_seconds node_exporter: Duration of a scrape job.
 # TYPE node_exporter_scrape_duration_seconds summary
 node_exporter_scrape_duration_seconds{collector="bonding",result="success",quantile="0.5"} 7.481600000000001e-05

collector/version.go

@@ -1,51 +0,0 @@
-// Copyright 2015 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package collector
-
-import (
-	"github.com/prometheus/client_golang/prometheus"
-)
-
-var (
-	Version  string
-	Revision string
-	Branch   string
-)
-
-type versionCollector struct {
-	metric *prometheus.GaugeVec
-}
-
-func init() {
-	Factories["version"] = NewVersionCollector
-}
-
-func NewVersionCollector() (Collector, error) {
-	metric := prometheus.NewGaugeVec(
-		prometheus.GaugeOpts{
-			Name: "node_exporter_build_info",
-			Help: "A metric with a constant '1' value labeled by version, revision, and branch from which the node_exporter was built.",
-		},
-		[]string{"version", "revision", "branch"},
-	)
-	metric.WithLabelValues(Version, Revision, Branch).Set(1)
-	return &versionCollector{
-		metric: metric,
-	}, nil
-}
-
-func (c *versionCollector) Update(ch chan<- prometheus.Metric) (err error) {
-	c.metric.Collect(ch)
-	return err
-}

node_exporter.go

@@ -18,6 +18,7 @@ import (
 	"fmt"
 	"net/http"
 	_ "net/http/pprof"
+	"os"
 	"sort"
 	"strings"
 	"sync"
@@ -25,17 +26,15 @@ import (
 
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/log"
+	"github.com/prometheus/common/version"
 	"github.com/prometheus/node_exporter/collector"
 )
 
 const (
-	defaultCollectors = "conntrack,cpu,diskstats,entropy,filefd,filesystem,loadavg,mdadm,meminfo,netdev,netstat,sockstat,stat,textfile,time,uname,version,vmstat"
+	defaultCollectors = "conntrack,cpu,diskstats,entropy,filefd,filesystem,loadavg,mdadm,meminfo,netdev,netstat,sockstat,stat,textfile,time,uname,vmstat"
 )
 
 var (
-	// Version of node_exporter. Set at build time.
-	Version = "0.0.0.dev"
-
 	scrapeDurations = prometheus.NewSummaryVec(
 		prometheus.SummaryOpts{
 			Namespace: collector.Namespace,
@@ -114,8 +113,13 @@ func loadCollectors(list string) (map[string]collector.Collector, error) {
 	return collectors, nil
 }
 
+func init() {
+	prometheus.MustRegister(version.NewCollector("node_exporter"))
+}
+
 func main() {
 	var (
+		showVersion       = flag.Bool("version", false, "Print version information.")
 		listenAddress     = flag.String("web.listen-address", ":9100", "Address on which to expose metrics and web interface.")
 		metricsPath       = flag.String("web.telemetry-path", "/metrics", "Path under which to expose metrics.")
 		enabledCollectors = flag.String("collectors.enabled", filterAvailableCollectors(defaultCollectors), "Comma-separated list of collectors to use.")
@@ -123,6 +127,14 @@ func main() {
 	)
 	flag.Parse()
 
+	if *showVersion {
+		fmt.Fprintln(os.Stdout, version.Print("node_exporter"))
+		os.Exit(0)
+	}
+
+	log.Infoln("Starting node_exporter", version.Info())
+	log.Infoln("Build context", version.BuildContext())
+
 	if *printCollectors {
 		collectorNames := make(sort.StringSlice, 0, len(collector.Factories))
 		for n := range collector.Factories {
@@ -161,7 +173,7 @@ func main() {
 			</html>`))
 	})
 
-	log.Infof("Starting node_exporter v%s at %s", Version, *listenAddress)
+	log.Infoln("Listening on", *listenAddress)
 	err = http.ListenAndServe(*listenAddress, nil)
 	if err != nil {
 		log.Fatal(err)

vendor/github.com/prometheus/common/version/info.go

@@ -0,0 +1,89 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package version
+
+import (
+	"bytes"
+	"fmt"
+	"runtime"
+	"strings"
+	"text/template"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+// Build information. Populated at build-time.
+var (
+	Version   string
+	Revision  string
+	Branch    string
+	BuildUser string
+	BuildDate string
+	GoVersion = runtime.Version()
+)
+
+// NewCollector returns a collector which exports metrics about current version information.
+func NewCollector(program string) *prometheus.GaugeVec {
+	buildInfo := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Namespace: program,
+			Name:      "build_info",
+			Help: fmt.Sprintf(
+				"A metric with a constant '1' value labeled by version, revision, branch, and goversion from which %s was built.",
+				program,
+			),
+		},
+		[]string{"version", "revision", "branch", "goversion"},
+	)
+	buildInfo.WithLabelValues(Version, Revision, Branch, GoVersion).Set(1)
+	return buildInfo
+}
+
+// versionInfoTmpl contains the template used by Info.
+var versionInfoTmpl = `
+{{.program}}, version {{.version}} (branch: {{.branch}}, revision: {{.revision}})
+  build user:       {{.buildUser}}
+  build date:       {{.buildDate}}
+  go version:       {{.goVersion}}
+`
+
+// Print returns version information.
+func Print(program string) string {
+	m := map[string]string{
+		"program":   program,
+		"version":   Version,
+		"revision":  Revision,
+		"branch":    Branch,
+		"buildUser": BuildUser,
+		"buildDate": BuildDate,
+		"goVersion": GoVersion,
+	}
+	t := template.Must(template.New("version").Parse(versionInfoTmpl))
+
+	var buf bytes.Buffer
+	if err := t.ExecuteTemplate(&buf, "version", m); err != nil {
+		panic(err)
+	}
+	return strings.TrimSpace(buf.String())
+}
+
+// Info returns version, branch and revision information.
+func Info() string {
+	return fmt.Sprintf("(version=%s, branch=%s, revision=%s)", Version, Branch, Revision)
+}
+
+// BuildContext returns goVersion, buildUser and buildDate information.
+func BuildContext() string {
+	return fmt.Sprintf("(go=%s, user=%s, date=%s)", GoVersion, BuildUser, BuildDate)
+}

vendor/vendor.json

@@ -72,6 +72,12 @@
 			"revision": "0a3005bb37bc411040083a55372e77c405f6464c",
 			"revisionTime": "2016-01-04T14:47:38+01:00"
 		},
+		{
+			"checksumSHA1": "91KYK0SpvkaMJJA2+BcxbVnyRO0=",
+			"path": "github.com/prometheus/common/version",
+			"revision": "dd586c1c5abb0be59e60f942c22af711a2008cb4",
+			"revisionTime": "2016-05-03T22:05:32Z"
+		},
 		{
 			"path": "github.com/prometheus/procfs",
 			"revision": "406e5b7bfd8201a36e2bb5f7bdae0b03380c2ce8",
@@ -87,5 +93,6 @@
 			"revision": "833a04a10549a95dc34458c195cbad61bbb6cb4d",
 			"revisionTime": "2015-12-10T17:34:15-08:00"
 		}
-	]
+	],
+	"rootPath": "github.com/prometheus/node_exporter"
 }