Add libvirt version info

Change-Id: I79e277f1eb31a5784d407e4c426c9b952f3c1334

collectors/version.go

@@ -0,0 +1,84 @@
+// Copyright 2019 VEXXHOST, Inc.
+//
+// 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 collectors
+
+import (
+	"fmt"
+
+	"github.com/libvirt/libvirt-go"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/common/log"
+)
+
+type VersionCollector struct {
+	prometheus.Collector
+
+	Connection *libvirt.Connect
+
+	Version *prometheus.Desc
+}
+
+func NewVersionCollector(conn *libvirt.Connect) (*VersionCollector, error) {
+	return &VersionCollector{
+		Connection: conn,
+
+		Version: prometheus.NewDesc(
+			"libvirtd_info",
+			"Version details for LibvirtD",
+			[]string{"driver", "driver_version", "version"}, nil,
+		),
+	}, nil
+}
+
+func (c *VersionCollector) Describe(ch chan<- *prometheus.Desc) {
+	ch <- c.Version
+}
+
+func (c *VersionCollector) Collect(ch chan<- prometheus.Metric) {
+	hypervisorType, err := c.Connection.GetType()
+	if err != nil {
+		log.Errorln(err)
+		return
+	}
+
+	hypervisorVersion, err := c.Connection.GetVersion()
+	if err != nil {
+		log.Errorln(err)
+		return
+	}
+
+	libvirtVersion, err := c.Connection.GetLibVersion()
+	if err != nil {
+		log.Errorln(err)
+		return
+	}
+
+	ch <- prometheus.MustNewConstMetric(
+		c.Version,
+		prometheus.CounterValue,
+		float64(1),
+		hypervisorType,
+		versionToString(hypervisorVersion),
+		versionToString(libvirtVersion),
+	)
+}
+
+func versionToString(version uint32) string {
+	major := version / 1000000
+	minor := (version - (major * 1000000)) / 1000
+	release := version - (major * 1000000) - (minor * 1000)
+
+	return fmt.Sprintf("%d.%d.%d", major, minor, release)
+}

libvirtd_exporter.go

@@ -57,12 +57,18 @@ func main() {
 	}
 	defer conn.Close()
 
+	versionCollector, err := collectors.NewVersionCollector(conn)
+	if err != nil {
+		log.Fatalln(err)
+	}
+
 	domainStats, err := collectors.NewDomainStatsCollector(conn, *libvirtNova)
 	if err != nil {
 		log.Fatalln(err)
 	}
 
 	prometheus.MustRegister(domainStats)
+	prometheus.MustRegister(versionCollector)
 
 	http.Handle("/metrics", promhttp.Handler())
 	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {