9 // Marshalled as binary by the UDP client, so be careful making changes.
10 type AnnounceRequest struct {
19 NumWant int32 // How many peer addresses are desired. -1 for default.
23 type AnnounceResponse struct {
24 Interval int32 // Minimum seconds the local peer should wait before next announce.
30 type AnnounceEvent int32
32 func (e AnnounceEvent) String() string {
33 // See BEP 3, "event".
34 return []string{"empty", "completed", "started", "stopped"}[e]
43 None AnnounceEvent = iota
44 Completed // The local peer just completed the torrent.
45 Started // The local peer has just resumed this torrent.
46 Stopped // The local peer is leaving the swarm.
49 type client interface {
50 Announce(*AnnounceRequest) (AnnounceResponse, error)
55 ErrBadScheme = errors.New("unknown scheme")
57 schemes = make(map[string]func(*url.URL) client)
60 func registerClientScheme(scheme string, newFunc func(*url.URL) client) {
61 schemes[scheme] = newFunc
64 // Returns ErrBadScheme if the tracker scheme isn't recognised.
65 func newClient(rawurl string) (cl client, err error) {
66 url_s, err := url.Parse(rawurl)
70 newFunc, ok := schemes[url_s.Scheme]
79 func Announce(urlStr string, req *AnnounceRequest) (res AnnounceResponse, err error) {
80 cl, err := newClient(urlStr)
85 return cl.Announce(req)