fail2ban-prometheus-exporter/src/exporter.go
Private Creator c208c8e97d feat: add listen address parameter
Add new -web.listen-address command line parameter, so that the
listening interface can be limited. This follows a similar style as
the official prometheus-node-exporter project.
Update project README with the new parameter.
2021-12-18 06:45:37 +00:00

81 lines
1.9 KiB
Go

package main
import (
"fail2ban-prometheus-exporter/cfg"
"fail2ban-prometheus-exporter/collector/f2b"
"fail2ban-prometheus-exporter/collector/textfile"
"fmt"
"log"
"net/http"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promhttp"
)
const (
metricsPath = "/metrics"
)
var (
version = "dev"
commit = "none"
date = "unknown"
builtBy = "unknown"
)
func printAppVersion() {
fmt.Println(version)
fmt.Printf(" build date: %s\r\n commit hash: %s\r\n built by: %s\r\n", date, commit, builtBy)
}
func rootHtmlHandler(w http.ResponseWriter, r *http.Request) {
_, err := w.Write([]byte(
`<html>
<head><title>Fail2Ban Exporter</title></head>
<body>
<h1>Fail2Ban Exporter</h1>
<p><a href="` + metricsPath + `">Metrics</a></p>
</body>
</html>`))
if err != nil {
log.Printf("error handling root url: %v", err)
w.WriteHeader(http.StatusInternalServerError)
}
}
func metricHandler(w http.ResponseWriter, r *http.Request, collector *textfile.Collector) {
promhttp.Handler().ServeHTTP(w, r)
collector.WriteTextFileMetrics(w, r)
}
func main() {
appSettings := cfg.Parse()
if appSettings.VersionMode {
printAppVersion()
} else {
addr := fmt.Sprintf("%s:%d", appSettings.MetricsAddress, appSettings.MetricsPort)
log.Printf("starting fail2ban exporter at %s", addr)
f2bCollector := f2b.NewExporter(appSettings, version)
prometheus.MustRegister(f2bCollector)
textFileCollector := textfile.NewCollector(appSettings)
prometheus.MustRegister(textFileCollector)
http.HandleFunc("/", rootHtmlHandler)
http.HandleFunc(metricsPath, func(w http.ResponseWriter, r *http.Request) {
metricHandler(w, r, textFileCollector)
})
log.Printf("metrics available at '%s'", metricsPath)
svrErr := make(chan error)
go func() {
svrErr <- http.ListenAndServe(addr, nil)
}()
log.Print("ready")
err := <-svrErr
log.Print(err)
}
}