package main import ( "errors" "flag" "html/template" "log" "net/http" "os" "path" "strings" "time" ) var porn EarthPorn var weather Weather var sun Sun func trylater(ch chan<- bool) { log.Println("Will try again later...") time.Sleep(1 * time.Minute) ch <- true } func earthPornUpdater(ch chan bool) { for _ = range ch { newporn, err := GetEarthPorn() if err != nil { log.Printf("Failed getting fap material: %s", err) go trylater(ch) } porn = newporn log.Println("New fap material!") } } func weatherUpdater(ch chan bool) { for _ = range ch { newW, newS, err := CurrentWeather() if err != nil { log.Printf("Failed getting latest weather data: %s", err) go trylater(ch) } weather = newW sun = newS log.Println("New weather data") } } func intervalUpdates(d time.Duration, stopch <-chan bool, chans ...chan<- bool) { send := func(chans ...chan<- bool) { for _, ch := range chans { go func(ch chan<- bool) { ch <- true }(ch) } } send(chans...) tick := time.NewTicker(d) for { select { case <-tick.C: send(chans...) case <-stopch: tick.Stop() for _, ch := range chans { close(ch) } return } } } var tpl *template.Template func loadTemplate() { gopaths := strings.Split(os.Getenv("GOPATH"), ":") for _, p := range gopaths { var err error tpl, err = template.ParseFiles(path.Join(p, "src", "github.com", "kch42", "startpage", "template.html")) if err == nil { return } } panic(errors.New("could not find template in $GOPATH/src/github.com/kch42/startpage")) } func main() { laddr := flag.String("laddr", ":25145", "Listen on this port") flag.Parse() loadTemplate() pornch := make(chan bool) weatherch := make(chan bool) stopch := make(chan bool) go intervalUpdates(30*time.Minute, stopch, pornch, weatherch) go weatherUpdater(weatherch) go earthPornUpdater(pornch) defer func(stopch chan<- bool) { stopch <- true }(stopch) http.HandleFunc("/", startpage) log.Fatal(http.ListenAndServe(*laddr, nil)) } type TplData struct { Porn *EarthPorn Weather *Weather Links []Link LCols int } func startpage(rw http.ResponseWriter, req *http.Request) { links := GetLinks() lcols := len(links) / 3 if lcols < 1 { lcols = 1 } else if lcols > 4 { lcols = 4 } if err := tpl.Execute(rw, &TplData{&porn, &weather, links, lcols}); err != nil { log.Printf("Failed executing template: %s\n", err) } }