/// <summary>
/// Perform an HTTP announce request to tracker and return any response.
/// </summary>
/// <param name="tracker"></param>
/// <returns>Announce response.</returns>
public AnnounceResponse Announce(Tracker tracker)
{
Tracker.LogAnnouce(tracker);
AnnounceResponse response = new AnnounceResponse();
try
{
_web.SetURL(BuildAnnouceURL(tracker));
if (_web.Get())
{
DecodeAnnounceResponse(tracker, _web.ResponseData, ref response);
}
else
{
throw new BitTorrentException(_web.StatusDescription);
}
}
catch (Exception ex)
{
Log.Logger.Error(ex);
throw;
}
return(response);
}
private readonly Bencode _Bencode; // Bencode encode/decode
/// <summary>
/// Decodes the announce request BEncoded response recieved from a tracker.
/// </summary>
/// <param name="announceResponse">Announce response.</param>
/// <param name="decodedResponse">Response.</param>
private void DecodeAnnounceResponse(Tracker tracker, byte[] announceResponse, ref AnnounceResponse decodedResponse)
{
if (announceResponse.Length != 0)
{
BNodeBase decodedAnnounce = _Bencode.Decode(announceResponse);
decodedResponse.statusMessage = _Bencode.GetDictionaryEntryString(decodedAnnounce, "failure reason");
if (decodedResponse.statusMessage != "")
{
decodedResponse.failure = true;
return; // If failure present then ignore rest of reply.
}
int.TryParse(_Bencode.GetDictionaryEntryString(decodedAnnounce, "complete"), out decodedResponse.complete);
int.TryParse(_Bencode.GetDictionaryEntryString(decodedAnnounce, "incomplete"), out decodedResponse.incomplete);
BNodeBase field = _Bencode.GetDictionaryEntry(decodedAnnounce, "peers");
if (field != null)
{
decodedResponse.peerList = new List <PeerDetails>();
if (field is BNodeString bNodeString) // Compact peer list reply
{
decodedResponse.peerList = tracker.GetCompactPeerList((bNodeString).str, 0);
}
else if (field is BNodeList bNodeList) // Non-compact peer list reply
{
foreach (var listItem in (bNodeList).list)
{
if (listItem is BNodeDictionary bNodeDictionary)
{
PeerDetails peer = new PeerDetails
{
infoHash = tracker.InfoHash
};
BNodeBase peerDictionaryItem = (bNodeDictionary);
BNodeBase peerField = _Bencode.GetDictionaryEntry(peerDictionaryItem, "ip");
if (peerField != null)
{
peer.ip = Encoding.ASCII.GetString(((BitTorrentLibrary.BNodeString)peerField).str);
}
if (peer.ip.Contains(":"))
{
peer.ip = peer.ip.Substring(peer.ip.LastIndexOf(":", StringComparison.Ordinal) + 1);
}
peerField = _Bencode.GetDictionaryEntry(peerDictionaryItem, "port");
if (peerField != null)
{
peer.port = int.Parse(Encoding.ASCII.GetString(((BitTorrentLibrary.BNodeNumber)peerField).number));
}
if (peer.ip != tracker.Ip) // Ignore self in peers list
{
Log.Logger.Trace($"(Tracker) Peer {peer.ip} Port {peer.port} found.");
decodedResponse.peerList.Add(peer);
}
}
}
}
}
int.TryParse(_Bencode.GetDictionaryEntryString(decodedAnnounce, "interval"), out decodedResponse.interval);
int.TryParse(_Bencode.GetDictionaryEntryString(decodedAnnounce, "min interval"), out decodedResponse.minInterval);
decodedResponse.trackerID = _Bencode.GetDictionaryEntryString(decodedAnnounce, "tracker id");
decodedResponse.statusMessage = _Bencode.GetDictionaryEntryString(decodedAnnounce, "warning message");
decodedResponse.announceCount++;
}
}