jellyfin-server/MediaBrowser.Server.Implementations/Udp/UdpServer.cs

269 lines
9.5 KiB
C#

using MediaBrowser.Common.Net;
using MediaBrowser.Controller.Configuration;
using MediaBrowser.Model.Logging;
using System;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Reactive.Linq;
using System.Text;
using System.Threading.Tasks;
namespace MediaBrowser.Server.Implementations.Udp
{
/// <summary>
/// Provides a Udp Server
/// </summary>
public class UdpServer : IDisposable
{
/// <summary>
/// The _logger
/// </summary>
private readonly ILogger _logger;
/// <summary>
/// The _network manager
/// </summary>
private readonly INetworkManager _networkManager;
/// <summary>
/// The _HTTP server
/// </summary>
private readonly IHttpServer _httpServer;
/// <summary>
/// The _server configuration manager
/// </summary>
private readonly IServerConfigurationManager _serverConfigurationManager;
/// <summary>
/// Initializes a new instance of the <see cref="UdpServer" /> class.
/// </summary>
/// <param name="logger">The logger.</param>
/// <param name="networkManager">The network manager.</param>
/// <param name="serverConfigurationManager">The server configuration manager.</param>
/// <param name="httpServer">The HTTP server.</param>
public UdpServer(ILogger logger, INetworkManager networkManager, IServerConfigurationManager serverConfigurationManager, IHttpServer httpServer)
{
_logger = logger;
_networkManager = networkManager;
_serverConfigurationManager = serverConfigurationManager;
_httpServer = httpServer;
}
/// <summary>
/// Raises the <see cref="E:MessageReceived" /> event.
/// </summary>
/// <param name="e">The <see cref="UdpMessageReceivedEventArgs"/> instance containing the event data.</param>
private async void OnMessageReceived(UdpMessageReceivedEventArgs e)
{
const string context = "Server";
var expectedMessage = String.Format("who is MediaBrowser{0}?", context);
var expectedMessageBytes = Encoding.UTF8.GetBytes(expectedMessage);
if (expectedMessageBytes.SequenceEqual(e.Bytes))
{
_logger.Info("Received UDP server request from " + e.RemoteEndPoint);
var localAddress = GetLocalIpAddress();
if (!string.IsNullOrEmpty(localAddress))
{
// Send a response back with our ip address and port
var response = String.Format("MediaBrowser{0}|{1}:{2}", context, GetLocalIpAddress(), _serverConfigurationManager.Configuration.HttpServerPortNumber);
await SendAsync(Encoding.UTF8.GetBytes(response), e.RemoteEndPoint);
}
else
{
_logger.Warn("Unable to respond to udp request because the local ip address could not be determined.");
}
}
}
/// <summary>
/// Gets the local ip address.
/// </summary>
/// <returns>System.String.</returns>
private string GetLocalIpAddress()
{
var localAddresses = _networkManager.GetLocalIpAddresses().ToList();
// Cross-check the local ip addresses with addresses that have been received on with the http server
var matchedAddress = _httpServer.LocalEndPoints
.ToList()
.Select(i => i.Split(':').FirstOrDefault())
.Where(i => !string.IsNullOrEmpty(i))
.FirstOrDefault(i => localAddresses.Contains(i, StringComparer.OrdinalIgnoreCase));
// Return the first matched address, if found, or the first known local address
return matchedAddress ?? localAddresses.FirstOrDefault();
}
/// <summary>
/// The _udp client
/// </summary>
private UdpClient _udpClient;
/// <summary>
/// Starts the specified port.
/// </summary>
/// <param name="port">The port.</param>
public void Start(int port)
{
_udpClient = new UdpClient(new IPEndPoint(IPAddress.Any, port));
_udpClient.Client.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
CreateObservable().Subscribe(OnMessageReceived);
}
/// <summary>
/// Creates the observable.
/// </summary>
/// <returns>IObservable{UdpReceiveResult}.</returns>
private IObservable<UdpReceiveResult> CreateObservable()
{
return Observable.Create<UdpReceiveResult>(obs =>
Observable.FromAsync(() =>
{
try
{
return _udpClient.ReceiveAsync();
}
catch (ObjectDisposedException)
{
return Task.FromResult(new UdpReceiveResult(new byte[]{}, new IPEndPoint(IPAddress.Any, 0)));
}
catch (Exception ex)
{
_logger.ErrorException("Error receiving udp message", ex);
return Task.FromResult(new UdpReceiveResult(new byte[] { }, new IPEndPoint(IPAddress.Any, 0)));
}
})
.Subscribe(obs))
.Repeat()
.Retry()
.Publish()
.RefCount();
}
/// <summary>
/// Called when [message received].
/// </summary>
/// <param name="message">The message.</param>
private void OnMessageReceived(UdpReceiveResult message)
{
if (message.RemoteEndPoint.Port == 0)
{
return;
}
var bytes = message.Buffer;
OnMessageReceived(new UdpMessageReceivedEventArgs
{
Bytes = bytes,
RemoteEndPoint = message.RemoteEndPoint.ToString()
});
}
/// <summary>
/// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
/// </summary>
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
/// <summary>
/// Stops this instance.
/// </summary>
public void Stop()
{
if (_udpClient != null)
{
_udpClient.Close();
}
}
/// <summary>
/// Releases unmanaged and - optionally - managed resources.
/// </summary>
/// <param name="dispose"><c>true</c> to release both managed and unmanaged resources; <c>false</c> to release only unmanaged resources.</param>
protected virtual void Dispose(bool dispose)
{
if (dispose)
{
Stop();
}
}
/// <summary>
/// Sends the async.
/// </summary>
/// <param name="data">The data.</param>
/// <param name="ipAddress">The ip address.</param>
/// <param name="port">The port.</param>
/// <returns>Task{System.Int32}.</returns>
/// <exception cref="System.ArgumentNullException">data</exception>
public Task SendAsync(string data, string ipAddress, int port)
{
return SendAsync(Encoding.UTF8.GetBytes(data), ipAddress, port);
}
/// <summary>
/// Sends the async.
/// </summary>
/// <param name="bytes">The bytes.</param>
/// <param name="ipAddress">The ip address.</param>
/// <param name="port">The port.</param>
/// <returns>Task{System.Int32}.</returns>
/// <exception cref="System.ArgumentNullException">bytes</exception>
public Task SendAsync(byte[] bytes, string ipAddress, int port)
{
if (bytes == null)
{
throw new ArgumentNullException("bytes");
}
if (string.IsNullOrEmpty(ipAddress))
{
throw new ArgumentNullException("ipAddress");
}
return _udpClient.SendAsync(bytes, bytes.Length, ipAddress, port);
}
/// <summary>
/// Sends the async.
/// </summary>
/// <param name="bytes">The bytes.</param>
/// <param name="remoteEndPoint">The remote end point.</param>
/// <returns>Task.</returns>
/// <exception cref="System.ArgumentNullException">
/// bytes
/// or
/// remoteEndPoint
/// </exception>
public async Task SendAsync(byte[] bytes, string remoteEndPoint)
{
if (bytes == null)
{
throw new ArgumentNullException("bytes");
}
if (string.IsNullOrEmpty(remoteEndPoint))
{
throw new ArgumentNullException("remoteEndPoint");
}
await _udpClient.SendAsync(bytes, bytes.Length, _networkManager.Parse(remoteEndPoint)).ConfigureAwait(false);
_logger.Info("Udp message sent to {0}", remoteEndPoint);
}
}
}