windows_exporter/exporter.go

76 lines
2.2 KiB
Go

package main
import (
"flag"
"log"
"net/http"
"sync"
"github.com/martinlindhe/wmi_exporter/collectors"
"github.com/prometheus/client_golang/prometheus"
)
// WmiExporter wraps all the WMI collectors and provides a single global
// exporter to extracts metrics out of. It also ensures that the collection
// is done in a thread-safe manner, the necessary requirement stated by
// prometheus. It also implements a prometheus.Collector interface in order
// to register it correctly.
type WmiExporter struct {
mu sync.Mutex
collectors []prometheus.Collector
}
// Verify that the WmiExporter implements the prometheus.Collector interface.
var _ prometheus.Collector = &WmiExporter{}
// NewWmiExporter creates an instance to WmiExporter and returns a reference
// to it. We can choose to enable a collector to extract stats out of by adding
// it to the list of collectors.
func NewWmiExporter() *WmiExporter {
return &WmiExporter{
collectors: []prometheus.Collector{
collectors.NewOSCollector(),
},
}
}
// Describe sends all the descriptors of the collectors included to
// the provided channel.
func (c *WmiExporter) Describe(ch chan<- *prometheus.Desc) {
for _, cc := range c.collectors {
cc.Describe(ch)
}
}
// Collect sends the collected metrics from each of the collectors to
// prometheus. Collect could be called several times concurrently
// and thus its run is protected by a single mutex.
func (c *WmiExporter) Collect(ch chan<- prometheus.Metric) {
c.mu.Lock()
defer c.mu.Unlock()
for _, cc := range c.collectors {
cc.Collect(ch)
}
}
func main() {
var (
addr = flag.String("telemetry.addr", ":9129", "host:port for WMI exporter")
metricsPath = flag.String("telemetry.path", "/metrics", "URL path for surfacing collected metrics")
)
flag.Parse()
prometheus.MustRegister(NewWmiExporter())
http.Handle(*metricsPath, prometheus.Handler())
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
http.Redirect(w, r, *metricsPath, http.StatusMovedPermanently)
})
log.Printf("Starting WMI exporter on %q", *addr)
if err := http.ListenAndServe(*addr, nil); err != nil {
log.Fatalf("cannot start WMI exporter: %s", err)
}
}