torrent/tracker/tracker.go

92 lines
2.3 KiB
Go

package tracker
import (
"context"
"errors"
"net/http"
"net/url"
"time"
"github.com/anacrolix/dht/v2/krpc"
)
// Marshalled as binary by the UDP client, so be careful making changes.
type AnnounceRequest struct {
InfoHash [20]byte
PeerId [20]byte
Downloaded int64
Left int64 // If less than 0, math.MaxInt64 will be used for HTTP trackers instead.
Uploaded int64
// Apparently this is optional. None can be used for announces done at
// regular intervals.
Event AnnounceEvent
IPAddress uint32
Key int32
NumWant int32 // How many peer addresses are desired. -1 for default.
Port uint16
} // 82 bytes
type AnnounceResponse struct {
Interval int32 // Minimum seconds the local peer should wait before next announce.
Leechers int32
Seeders int32
Peers []Peer
}
type AnnounceEvent int32
func (e AnnounceEvent) String() string {
// See BEP 3, "event".
return []string{"empty", "completed", "started", "stopped"}[e]
}
const (
None AnnounceEvent = iota
Completed // The local peer just completed the torrent.
Started // The local peer has just resumed this torrent.
Stopped // The local peer is leaving the swarm.
)
var (
ErrBadScheme = errors.New("unknown scheme")
)
type Announce struct {
TrackerUrl string
Request AnnounceRequest
HostHeader string
HTTPProxy func(*http.Request) (*url.URL, error)
ServerName string
UserAgent string
UdpNetwork string
// If the port is zero, it's assumed to be the same as the Request.Port.
ClientIp4 krpc.NodeAddr
// If the port is zero, it's assumed to be the same as the Request.Port.
ClientIp6 krpc.NodeAddr
Context context.Context
}
func (me Announce) Do() (res AnnounceResponse, err error) {
_url, err := url.Parse(me.TrackerUrl)
if err != nil {
return
}
if me.Context == nil {
// This is just to maintain the old behaviour that should be a timeout of 15s. Users can
// override it by providing their own Context. See comments elsewhere about longer timeouts
// acting as rate limiting overloaded trackers.
ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
defer cancel()
me.Context = ctx
}
switch _url.Scheme {
case "http", "https":
return announceHTTP(me, _url)
case "udp", "udp4", "udp6":
return announceUDP(me, _url)
default:
err = ErrBadScheme
return
}
}