torrent/tracker/http.go

97 lines
2.5 KiB
Go

package tracker
import (
"bytes"
"errors"
"fmt"
"io"
"net"
"net/http"
"net/url"
"strconv"
"github.com/anacrolix/missinggo/httptoo"
"github.com/anacrolix/torrent/bencode"
"github.com/anacrolix/torrent/util"
)
type httpResponse struct {
FailureReason string `bencode:"failure reason"`
Interval int32 `bencode:"interval"`
TrackerId string `bencode:"tracker id"`
Complete int32 `bencode:"complete"`
Incomplete int32 `bencode:"incomplete"`
Peers interface{} `bencode:"peers"`
}
func (r *httpResponse) UnmarshalPeers() (ret []Peer, err error) {
s, ok := r.Peers.(string)
if !ok {
err = fmt.Errorf("unsupported peers value type: %T", r.Peers)
return
}
cp, err := util.UnmarshalIPv4CompactPeers([]byte(s))
if err != nil {
return
}
ret = make([]Peer, 0, len(cp))
for _, p := range cp {
ret = append(ret, Peer{net.IP(p.IP[:]), int(p.Port)})
}
return
}
func setAnnounceParams(_url *url.URL, ar *AnnounceRequest) {
q := _url.Query()
q.Set("info_hash", string(ar.InfoHash[:]))
q.Set("peer_id", string(ar.PeerId[:]))
q.Set("port", fmt.Sprintf("%d", ar.Port))
q.Set("uploaded", strconv.FormatInt(ar.Uploaded, 10))
q.Set("downloaded", strconv.FormatInt(ar.Downloaded, 10))
q.Set("left", strconv.FormatUint(ar.Left, 10))
if ar.Event != None {
q.Set("event", ar.Event.String())
}
// http://stackoverflow.com/questions/17418004/why-does-tracker-server-not-understand-my-request-bittorrent-protocol
q.Set("compact", "1")
// According to https://wiki.vuze.com/w/Message_Stream_Encryption.
q.Set("supportcrypto", "1")
_url.RawQuery = q.Encode()
}
func announceHTTP(ar *AnnounceRequest, _url *url.URL, host string) (ret AnnounceResponse, err error) {
_url = httptoo.CopyURL(_url)
setAnnounceParams(_url, ar)
req, err := http.NewRequest("GET", _url.String(), nil)
req.Host = host
resp, err := http.DefaultClient.Do(req)
if err != nil {
return
}
defer resp.Body.Close()
var buf bytes.Buffer
io.Copy(&buf, resp.Body)
if resp.StatusCode != 200 {
err = fmt.Errorf("response from tracker: %s: %s", resp.Status, buf.String())
return
}
var trackerResponse httpResponse
err = bencode.Unmarshal(buf.Bytes(), &trackerResponse)
if err != nil {
err = fmt.Errorf("error decoding %q: %s", buf.Bytes(), err)
return
}
if trackerResponse.FailureReason != "" {
err = errors.New(trackerResponse.FailureReason)
return
}
ret.Interval = trackerResponse.Interval
ret.Leechers = trackerResponse.Incomplete
ret.Seeders = trackerResponse.Complete
ret.Peers, err = trackerResponse.UnmarshalPeers()
return
}