/// <summary>
/// Checks if the response packet matches the specified request packet.
/// </summary>
/// <param name="dp">The request packet.</param>
public override bool Matches(DiscoveryMetadata dp)
{
var request = dp as DiscoveryRequest;
if (request == null)
{
return(false);
}
try
{
if (!Regex.IsMatch(HostUrl, request.NamePattern))
{
return(false);
}
}
catch (ArgumentException)
{
// invalid regular expression
return(false);
}
if (Version == null && request.Version != null)
{
return(false);
}
return(request.Version == null || Version == request.Version);
}
/// <summary>
/// Checks if the response packet matches the specified request packet.
/// </summary>
/// <param name="dp">The request packet.</param>
public override bool Matches(DiscoveryMetadata dp)
{
var request = dp as DiscoveryRequest;
if (request == null)
{
return false;
}
try
{
if (!Regex.IsMatch(HostUrl, request.NamePattern))
{
return false;
}
}
catch (ArgumentException)
{
// invalid regular expression
return false;
}
if (Version == null && request.Version != null)
{
return false;
}
return request.Version == null || Version == request.Version;
}
/// <summary>
/// Initializes a new instance of the <see cref="DiscoveryServer"/> class.
/// </summary>
/// <param name="responseMetadata">The response metadata.</param>
/// <param name="port">The port to bind to.</param>
/// <param name="localAddress">The local address to bind to.</param>
public DiscoveryServer(DiscoveryMetadata responseMetadata, int port = DefaultDiscoveryPort, IPAddress localAddress = null)
{
if (responseMetadata == null)
{
throw new ArgumentNullException("responseMetadata", "Discovery response metadata is missing.");
}
Port = port;
LocalAddress = localAddress ?? IPAddress.Any;
ResponseMetadata = responseMetadata;
ResponseMetadataPacket = DiscoveryMetadataHelper.Encode(ResponseMetadata);
}
/// <summary>
/// Initializes a new instance of the <see cref="DiscoveryClient"/> class.
/// </summary>
/// <param name="requestMetadata">The request metadata.</param>
/// <param name="port">The port of the discovery server.</param>
public DiscoveryClient(DiscoveryMetadata requestMetadata, int port = DiscoveryServer.DefaultDiscoveryPort)
{
if (requestMetadata == null)
{
throw new ArgumentNullException("requestMetadata", "Discovery request metadata is missing.");
}
Port = port;
RequestMetadata = requestMetadata;
RequestMetadataPacket = DiscoveryMetadataHelper.Encode(RequestMetadata);
DestinationAddress = IPAddress.Broadcast;
DestinationEndpoint = new IPEndPoint(DestinationAddress, Port);
Results = new HashSet<DiscoveryMetadata>();
RetryTimeout = TimeSpan.FromSeconds(1);
RetryCount = 10;
}
/// <summary>
/// Encodes the specified discovery metadata packet into byte array.
/// </summary>
/// <param name="dp">The packet to encode.</param>
public static byte[] Encode(DiscoveryMetadata dp)
{
// convert the packet into string
var sb = new StringBuilder();
sb.AppendFormat("{0}|", Escape(dp.Signature));
foreach (var entry in dp.Properties)
{
sb.AppendFormat("{0}={1}|", Escape(entry.Key), Escape(entry.Value));
}
// calculate checksum and merge
var content = Encoding.UTF8.GetBytes(sb.ToString());
var crc = new Crc32Calculator();
crc.UpdateWithBlock(content, 0, content.Length);
var checksum = BitConverter.GetBytes(crc.Crc32);
var contentLength = BitConverter.GetBytes(content.Length);
// packet contents: length, checksum, content
return(contentLength.Concat(checksum).Concat(content).ToArray());
}
/// <summary>
/// Initializes a new instance of the <see cref="DiscoveryEventArgs"/> class.
/// </summary>
/// <param name="metadata">Discovery metadata.</param>
public DiscoveryEventArgs(DiscoveryMetadata metadata)
{
Metadata = metadata;
}
/// <summary>
/// Checks if the packet matches the specified request.
/// </summary>
/// <param name="request">The request.</param>
public virtual bool Matches(DiscoveryMetadata request)
{
return false;
}
private void HandleResponse(DiscoveryMetadata response)
{
lock (lockObject)
{
if (response == null || Results.Contains(response))
{
return;
}
Results.Add(response);
}
OnDiscovered(new DiscoveryEventArgs(response));
}
/// <summary>
/// Checks if the packet matches the specified request.
/// </summary>
/// <param name="request">The request.</param>
public virtual bool Matches(DiscoveryMetadata request)
{
return(false);
}
/// <summary>
/// Encodes the specified discovery metadata packet into byte array.
/// </summary>
/// <param name="dp">The packet to encode.</param>
public static byte[] Encode(DiscoveryMetadata dp)
{
// convert the packet into string
var sb = new StringBuilder();
sb.AppendFormat("{0}|", Escape(dp.Signature));
foreach (var entry in dp.Properties)
{
sb.AppendFormat("{0}={1}|", Escape(entry.Key), Escape(entry.Value));
}
// calculate checksum and merge
var content = Encoding.UTF8.GetBytes(sb.ToString());
var crc = new Crc32Calculator();
crc.UpdateWithBlock(content, 0, content.Length);
var checksum = BitConverter.GetBytes(crc.Crc32);
var contentLength = BitConverter.GetBytes(content.Length);
// packet contents: length, checksum, content
return contentLength.Concat(checksum).Concat(content).ToArray();
}
