func main() {
// load '.env' file if present
env.Load()
// ensure FORWARD_URL
if _, err := env.Require("FORWARD_URL"); err != nil {
log.Fatal("at=main on=env.Require error", err)
}
http.HandleFunc("/", handler)
listener := fmt.Sprintf(
"%s:%s",
env.Get("ADDR"),
env.GetOrSet("PORT", "3000"),
)
log.Print("at=main on=startup listener", listener)
log.Fatal(http.ListenAndServe(listener, nil))
}
func handler(w http.ResponseWriter, r *http.Request) {
begin := time.Now()
status := http.StatusOK // default to 200, override when error
// always log method, path, status and took when finishing
defer func(code int) {
log.Print(
"at=main on=handler method", r.Method,
"path", r.URL.Path,
"status", code,
"took", time.Since(begin),
)
}(status)
// handler http.Error and set status for use in above
// defer function
httpError := func(code int) {
status = code
http.Error(w, http.StatusText(code), code)
}
if r.Method != "POST" {
httpError(http.StatusMethodNotAllowed)
return
}
// handle basic auth when USERNAME and PASSWORD are set
username := env.Get("USERNAME")
password := env.Get("PASSWORD")
if username != "" && password != "" {
user, pass, ok := r.BasicAuth()
if !ok {
log.Print("at=main on=handler action=<req>.BasicAuth() ok=false")
// support AWS's two attempt authentication
w.Header().Set("WWW-Authenticate", "Basic realm=\"hello\"")
httpError(http.StatusUnauthorized)
return
}
log.Debug("at=main on=handler action=<req>.BasicAuth() ok=true user", user, "pass", pass)
if !(user == username && pass == password) {
log.Print("at=main on=handler action=<req>.BasicAuth() error", http.StatusText(http.StatusUnauthorized))
httpError(http.StatusUnauthorized)
return
}
}
// parse body and deal
body, err := ioutil.ReadAll(r.Body)
if err != nil {
log.Print("at=main on=handler action=ioutil.ReadAll(body) error", err)
httpError(http.StatusInternalServerError)
return
}
log.Debug("at=main on=handler body", body)
confirm := confirmation.Parse(body)
if confirm != nil {
err = confirm.Do()
if err != nil {
log.Print("at=main on=handler action=<Confirmation>.Do() error", err)
httpError(http.StatusBadRequest)
return
}
log.Print("at=main on=handler action=<Confirmation>.Do() ok=true")
return
}
fwdr := forwarder.New(body)
if err := fwdr.Do(); err != nil {
log.Print("at=main on=handler action=<Forwarder>.Do() error", err)
httpError(http.StatusRequestedRangeNotSatisfiable)
}
log.Print("at=main on=handler action=<Forwarder>.Do() ok=true")
}