package main
import (
"flag"
"fmt"
"html/template"
"net/http"
"time"
"blitiri.com.ar/go/log"
// To enable live profiling in the monitoring server.
_ "net/http/pprof"
)
func launchMonitoringServer(addr string) {
log.Infof("Monitoring HTTP server listening on %s", addr)
indexData := struct {
Version string
SourceDate time.Time
StartTime time.Time
}{
Version: version,
SourceDate: sourceDate,
StartTime: time.Now(),
}
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
if r.URL.Path != "/" {
http.NotFound(w, r)
return
}
if err := monitoringHTMLIndex.Execute(w, indexData); err != nil {
log.Infof("monitoring handler error: %v", err)
}
})
flags := dumpFlags()
http.HandleFunc("/debug/flags", func(w http.ResponseWriter, r *http.Request) {
_, _ = w.Write([]byte(flags))
})
go http.ListenAndServe(addr, nil)
}
// Static index for the monitoring website.
var monitoringHTMLIndex = template.Must(template.New("index").Funcs(
template.FuncMap{"since": time.Since}).Parse(
`
chasquid monitoring
chasquid monitoring
chasquid {{.Version}}
source date {{.SourceDate.Format "2006-01-02 15:04:05 -0700"}}
started {{.StartTime.Format "Mon, 2006-01-02 15:04:05 -0700"}}
up since {{.StartTime | since}}
`))
// dumpFlags to a string, for troubleshooting purposes.
func dumpFlags() string {
s := ""
visited := make(map[string]bool)
// Print set flags first, then the rest.
flag.Visit(func(f *flag.Flag) {
s += fmt.Sprintf("-%s=%s\n", f.Name, f.Value.String())
visited[f.Name] = true
})
s += "\n"
flag.VisitAll(func(f *flag.Flag) {
if !visited[f.Name] {
s += fmt.Sprintf("-%s=%s\n", f.Name, f.Value.String())
}
})
return s
}