Hi i have got a TCP/IP Socket project.
i can send string messages to Server with Client side and i can get responses from server.
But getting one string message and sending only one string (or any other object).I wanna Encode Personel class to Byte array after send to Clients from server side.And Decode it. than get values from my class.
//SERVER SIDE CODE Connect() starts at on form load
private void Connect()
{
// start listen socket
dinleyiciSoket = new TcpListener(System.Net.IPAddress.Any, 10048);
dinleyiciSoket.Start();
Socket istemciSoketi = dinleyiciSoket.AcceptSocket();
NetworkStream agAkisi = new NetworkStream(istemciSoketi);
BinaryReader binaryOkuyucu = new BinaryReader(agAkisi);
BinaryWriter binaryYazici = new BinaryWriter(agAkisi);
string alinanMetin = binaryOkuyucu.ReadString();
MessageBox.Show(alinanMetin, "Yeni Genelge", MessageBoxButtons.OK);
binaryYazici.Write(true);
dinleyiciSoket.Stop();
Connect();
}
////////// CLIENT SIDE //////////////
private string IpAdresi(string host)
{
string address = "";
IPAddress[] addresslist = Dns.GetHostAddresses(host);
foreach (IPAddress theaddress in addresslist)
{
if (theaddress.AddressFamily == AddressFamily.InterNetwork)
{
address = theaddress.ToString();
}
}
return address;
}
bool onay;
private void button1_Click(object sender, EventArgs e)
{
//create socket connection
Socket istemciBaglantisi = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
//Bağlantıyı gerçekleştir
if (istemciBaglantisi.Connected != true)
{
istemciBaglantisi.Connect(IPAddress.Parse(IpAdresi(txtHost.Text)), 10048);
}
agAkisi = new NetworkStream(istemciBaglantisi);
binaryYazici = new BinaryWriter(agAkisi);
binaryOkuyucu = new BinaryReader(agAkisi);
binaryYazici.Write(txtMesaj.Text);
onay = binaryOkuyucu.ReadBoolean();
MessageBox.Show(onay.ToString());
istemciBaglantisi.Close();
}
Take a look at object serialization. See here for examples. That should get you going in the right direction.
You can use google's protocol buffers. It is a fast and compact mechanism for serializing objects. There are two implementations on .NET: protobuf-net and protobuf.
I'd use object serialization or XmlSerialization, both available in .NET. I would not look at Google's protocol buffers, because that RPC encoding has little advantage over what's already in .NET, but it is obscure, especially in the .NET world, and especially now. I wouldn't bet on it becoming mainstream for .net devs. As a result, you will only make your code harder to maintain by using this RPC encoding.
I don't really see the need for protobufs when the apps that are interconnecting are homogeneous, and are NOT on the scale of Google's datacenters. I also don't see the need even when heterogeneity is the rule, because we already have JSON and XML. They are both readable and serviceable, where protobufs are not.
In any case .NET has what you need for this, built-in.
Related
I have a hardware that streams data to a windows server, and I have IP and port of this server. Now I want to connect unity app as a TCP client to this server. I have tried many solutions, but still have hard time to figure out best way to do this. Any help is highly appreciated. One issue that I have with current tutorials is that most of them define a unity server and try to connect another unity app as client and mostly based on localhost. However, I just want to connect a unity app as a TCP client to a server which I have IP and port.
Warm regards,
enter image description here
First of all, at the top of your script:
using System;
using System.Net.Sockets;
Then, create an instance of TcpClient and begin the connection:
socket = new TcpClient
{
// dataBufferSize is in bytes
ReceiveBufferSize = dataBufferSize,
SendBufferSize = dataBufferSize
};
socket.BeginConnect(ip, port, ConnectCallback, socket);
In ConnectCallback():
private void ConnectCallback(IAsyncResult asyncResult)
{
socket.EndConnect(asyncResult);
if (!socket.Connected) return;
// stream is a NetworkStream you should declare somewhere
stream = socket.GetStream();
// receiveBuffer is a byte[] you should declare somewhere
receiveBuffer = new byte[dataBufferSize];
stream.BeginRead(receiveBuffer, 0, dataBufferSize, ReceiveCallback, null);
}
In ReceiveCallback():
private void ReceiveCallback(IAsyncResult asyncResult)
{
try
{
int byteLength = stream.EndRead(asyncResult);
if (byteLength <= 0)
{
// Disconnect client
return;
}
// Transfer data from receiveBuffer to data variable for handling
byte[] data = new byte[byteLength];
Array.Copy(receiveBuffer, data, byteLength);
// Handle data in any way you want to
// BeginRead again so you can keep receiving data
stream.BeginRead(receiveBuffer, 0, dataBufferSize, ReceiveCallback, null);
}
catch (Exception e)
{
Console.WriteLine($"Error receiving TCP data: {e.Message}");
}
}
I got this information from this tutorial.
I have managed to basically connect with my friend over internet, by forwarding my IP address from my router settings... this is not viable because there are few people willing to do what I did to play games with their friends. So how to actually do UDP hole punching (basically what I did manually to my router) in unity using the mirror networking solution...
A common solution to this problem is WebRTC, which takes care of the hole punching under the hood. Unity maintains this package which implements WebRTC. They also provide a great tutorial on how to use it. The nuts and bolts of it are:
using UnityEngine;
using Unity.WebRTC;
public class MyPlayerScript : MonoBehaviour
{
RTCPeerConnection localConnection, remoteConnection;
RTCDataChannel sendChannel, receiveChannel;
private void Awake()
{
// Initialize WebRTC
WebRTC.Initialize();
// Create local peer
localConnection = new RTCPeerConnection();
sendChannel = localConnection.CreateDataChannel("sendChannel");
channel.OnOpen = handleSendChannelStatusChange;
channel.OnClose = handleSendChannelStatusChange;
// Create remote peer
remoteConnection = new RTCPeerConnection();
remoteConnection.OnDataChannel = ReceiveChannelCallback;
// register comms paths
localConnection.OnIceCandidate = e => {
!string.IsNullOrEmpty(e.candidate)
|| remoteConnection.AddIceCandidate(ref e);
}
remoteConnection.OnIceCandidate = e => {
!string.IsNullOrEmpty(e.candidate)
|| localConnection.AddIceCandidate(ref e);
}
localConnection.OnIceConnectionChange = state => {
Debug.Log(state);
}
}
//handle begin
IEnumerator Call(){
var op1 = localConnection.CreateOffer();
yield return op1;
var op2 = localConnection.SetLocalDescription(ref op1.desc);
yield return op2;
var op3 = remoteConnection.SetRemoteDescription(ref op1.desc);
yield return op3;
var op4 = remoteConnection.CreateAnswer();
yield return op4;
var op5 = remoteConnection.setLocalDescription(op4.desc);
yield return op5;
var op6 = localConnection.setRemoteDescription(op4.desc);
yield return op6;
}
//handle send messages
void SendMessage(string message)
{
sendChannel.Send(message);
}
void SendBinary(byte[] bytes)
{
sendChannel.Send(bytes);
}
//handle receive messages
void ReceiveChannelCallback(RTCDataChannel channel)
{
receiveChannel = channel;
receiveChannel.OnMessage = HandleReceiveMessage;
}
void HandleReceiveMessage(byte[] bytes)
{
var message = System.Text.Encoding.UTF8.GetString(bytes);
Debug.Log(message);
}
//handle end
private void OnDestroy()
{
sendChannel.Close();
receiveChannel.Close();
localConnection.Close();
remoteConnection.Close();
WebRTC.Finalize();
}
}
I have also found a useful way to do this using mirror and the epic free relay for this. Thanks so much for the other answers, it really helped understand better what I needed to search and use!
You can use Photon Bolt or Photon Fusion to let players host a game on their local machine like minecraft, etc. Photon provides relay as well as tries to use STUN to establish direct peer to peer connection to the host via UDP. PUN2 is also a good choice, although I like Photon Bolt/Fusion better - it's less of a simple RPC framework and more programmer oriented. Also, PUN does not do any STUN direct peer connection, it will always be relayed. Photon Bolt and Fusion will first attempt a STUN direct peer connection and then fallback to relay if necessary. It's been around for years and is the best choice.
Sure you can develop a Unity game with Mirror (although without a relay built in) but it's not nearly as easy to setup and use as Photon Bolt/Fusion and they don't provide a relay. As someone mentioned, you might be able to hack something together in some way but yeah - not recommended.
Ugh, yeah don't use WebRTC for a Unity game (or probably anything other than streaming music/video like it was made for to be honest).
Unity's MLAPI is "under development" and their last API was suddenly dropped "deprecated", so I wouldn't use that.
//StockPriceEmitter is a "dead loop" thread which generate data, and invoke StockPriceService.onUpdates() to send data.
#Service
public class StockPriceService implements StockPriceEmitter.Listener
{
#Inject
private BayeuxServer bayeuxServer;
#Session
private LocalSession sender;
public void onUpdates(List<StockPriceEmitter.Update> updates)
{
for (StockPriceEmitter.Update update : updates)
{
// Create the channel name using the stock symbol
String channelName = "/stock/" + update.getSymbol().toLowerCase(Locale.ENGLISH);
// Initialize the channel, making it persistent and lazy
bayeuxServer.createIfAbsent(channelName, new ConfigurableServerChannel.Initializer()
{
public void configureChannel(ConfigurableServerChannel channel)
{
channel.setPersistent(true);
channel.setLazy(true);
}
});
// Convert the Update business object to a CometD-friendly format
Map<String, Object> data = new HashMap<String, Object>(4);
data.put("symbol", update.getSymbol());
data.put("oldValue", update.getOldValue());
data.put("newValue", update.getNewValue());
// Publish to all subscribers
ServerChannel channel = bayeuxServer.getChannel(channelName);
channel.publish(sender, data, null); // this code works fine
//this.sender.getServerSession().deliver(sender, channel.getId(), data, null); // this code does not work
}
}
}
this line channel.publish(sender, data, null); // this code works fine works fine, now I don't want channel to publish message to all clients subscirbed with it, I want to send to a specific client, so I write this this.sender.getServerSession().deliver(sender, channel.getId(), data, null);, but it does not work, browser can't get message.
thx in advance.
I strongly recommend that you spend some time reading the CometD concepts page, in particular the section about sessions.
Your code does not work because you are sending the message to the sender, not to the recipient.
You need to pick which remote ServerSession you want to send the message to among the many that may be connected to your server, and call serverSession.deliver(...) on that remote ServerSession.
How to pick the remote ServerSession depends on your application.
For example:
for (ServerSession session : bayeuxServer.getSessions())
{
if (isAdminUser(session))
session.deliver(sender, channel.getId(), data, null);
}
You have to provide an implementation of isAdmin(ServerSession) with your logic, of course.
Note that you don't need to iterate over the sessions: if you happen to know the session id to deliver to, you can do:
bayeuxServer.getSession(sessionId).deliver(sender, channel.getId(), data, null);
Also refer to the CometD chat demo shipped with the CometD distribution, that contain a full fledged example of how to send a message to particular session.
I am trying to implement Facebook X_FACEBOOK_PLATFORM SASL mechanism so I could integrate Facebook Chat to my application over XMPP.
Here is the code:
var ak = "my app id";
var sk = "access token";
var aps = "my app secret";
using (var client = new TcpClient())
{
client.Connect("chat.facebook.com", 5222);
using (var writer = new StreamWriter(client.GetStream())) using (var reader = new StreamReader(client.GetStream()))
{
// Write for the first time
writer.Write("<stream:stream xmlns=\"jabber:client\" xmlns:stream=\"http://etherx.jabber.org/streams\" version=\"1.0\" to=\"chat.facebook.com\"><auth xmlns=\"urn:ietf:params:xml:ns:xmpp-sasl\" mechanism=\"X-FACEBOOK-PLATFORM\" /></stream:stream>");
writer.Flush();
Thread.Sleep(500);
// I am pretty sure following works or at least it's not what causes the error
var challenge = Encoding.UTF8.GetString(Convert.FromBase64String(XElement.Parse(reader.ReadToEnd()).Elements().Last().Value)).Split('&').Select(s => s.Split('=')).ToDictionary(s => s[0], s => s[1]);
var response = new SortedDictionary<string, string>() { { "api_key", ak }, { "call_id", DateTime.Now.Ticks.ToString() }, { "method", challenge["method"] }, { "nonce", challenge["nonce"] }, { "session_key", sk }, { "v", "1.0" } };
var responseString1 = string.Format("{0}{1}", string.Join(string.Empty, response.Select(p => string.Format("{0}={1}", p.Key, p.Value)).ToArray()), aps);
byte[] hashedResponse1 = null;
using (var prov = new MD5CryptoServiceProvider()) hashedResponse1 = prov.ComputeHash(Encoding.UTF8.GetBytes(responseString1));
var builder = new StringBuilder();
foreach (var item in hashedResponse1) builder.Append(item.ToString("x2"));
var responseString2 = Convert.ToBase64String(Encoding.UTF8.GetBytes(string.Format("{0}&sig={1}", string.Join("&", response.Select(p => string.Format("{0}={1}", p.Key, p.Value)).ToArray()), builder.ToString().ToLower()))); ;
// Write for the second time
writer.Write(string.Format("<response xmlns=\"urn:ietf:params:xml:ns:xmpp-sasl\">{0}</response>", responseString2));
writer.Flush();
Thread.Sleep(500);
MessageBox.Show(reader.ReadToEnd());
}
}
I shortened and shrunk the code as much as possible, because I think my SASL implementation (whether it works or not, I haven't had a chance to test it yet) is not what causes the error.
I get the following exception thrown at my face: Unable to read data from the transport connection: An established connection was aborted by the software in your host machine.
10053
System.Net.Sockets.SocketError.ConnectionAborted
It happens every time I try to read from client's stream for the second time. As you can see i pause a thread here so Facebook server has enough time to answer me, but I used asynchronous approach before and I encountered the exact same thing, so I decided to try it synchronously first. Anyway actual SASL mechanism implementation really shouldn't cause this because if I don't try to authenticate right away, but I send the request to see what mechanisms server uses and select that mechanism in another round of reading and writing, it fails, but when I send mechanism selection XML right away, it works and fails on whatever second I send.
So the conclusion is following: I open the socket connection, write to it, read from it (first read works both sync and async), write to it for the second time and try to read from it for the second time and here it always fails. Clearly then, problem is with socket connection itself. I tried to use new StreamReader for second read but to no avail. This is rather unpleasant since I would really like to implement facade over NetworkStream with "Received" event or something like Send(string data, Action<string> responseProcessor) to get some comfort working with that stream, and I already had the implementation, but it also failed on second read.
Thanks for your suggestions.
Edit: Here is the code of facade over NetworkStream. Same thing happens when using this asynchronous approach, but couple of hours ago it worked, but for second response returned same string as for first. I can't figute out what I changed in a meantime and how.
public void Send(XElement fragment)
{
if (Sent != null) Sent(this, new XmppEventArgs(fragment));
byte[] buffer = new byte[1024];
AsyncCallback callback = null;
callback = (a) =>
{
var available = NetworkStream.EndRead(a);
if (available > 0)
{
StringBuilder.Append(Encoding.UTF8.GetString(buffer, 0, available));
NetworkStream.BeginRead(buffer, 0, buffer.Length, callback, buffer);
}
else
{
var args = new XmppEventArgs(XElement.Parse(StringBuilder.ToString()));
if (Received != null) Received(this, args);
StringBuilder = new StringBuilder();
// NetworkStream.BeginRead(buffer, 0, buffer.Length, callback, buffer);
}
};
NetworkStream.BeginRead(buffer, 0, buffer.Length, callback, buffer);
NetworkStreamWriter.Write(fragment);
NetworkStreamWriter.Flush();
}
The reader.ReadToEnd() call consumes everything until end-of-stream, i.e. until TCP connection is closed.
A friend of mine came to me with a problem: when using the NetworkStream class on the server end of the connection, if the client disconnects, NetworkStream fails to detect it.
Stripped down, his C# code looked like this:
List<TcpClient> connections = new List<TcpClient>();
TcpListener listener = new TcpListener(7777);
listener.Start();
while(true)
{
if (listener.Pending())
{
connections.Add(listener.AcceptTcpClient());
}
TcpClient deadClient = null;
foreach (TcpClient client in connections)
{
if (!client.Connected)
{
deadClient = client;
break;
}
NetworkStream ns = client.GetStream();
if (ns.DataAvailable)
{
BinaryFormatter bf = new BinaryFormatter();
object o = bf.Deserialize(ns);
ReceiveMyObject(o);
}
}
if (deadClient != null)
{
deadClient.Close();
connections.Remove(deadClient);
}
Thread.Sleep(0);
}
The code works, in that clients can successfully connect and the server can read data sent to it. However, if the remote client calls tcpClient.Close(), the server does not detect the disconnection - client.Connected remains true, and ns.DataAvailable is false.
A search of Stack Overflow provided an answer - since Socket.Receive is not being called, the socket is not detecting the disconnection. Fair enough. We can work around that:
foreach (TcpClient client in connections)
{
client.ReceiveTimeout = 0;
if (client.Client.Poll(0, SelectMode.SelectRead))
{
int bytesPeeked = 0;
byte[] buffer = new byte[1];
bytesPeeked = client.Client.Receive(buffer, SocketFlags.Peek);
if (bytesPeeked == 0)
{
deadClient = client;
break;
}
else
{
NetworkStream ns = client.GetStream();
if (ns.DataAvailable)
{
BinaryFormatter bf = new BinaryFormatter();
object o = bf.Deserialize(ns);
ReceiveMyObject(o);
}
}
}
}
(I have left out exception handling code for brevity.)
This code works, however, I would not call this solution "elegant". The other elegant solution to the problem I am aware of is to spawn a thread per TcpClient, and allow the BinaryFormatter.Deserialize (née NetworkStream.Read) call to block, which would detect the disconnection correctly. Though, this does have the overhead of creating and maintaining a thread per client.
I get the feeling that I'm missing some secret, awesome answer that would retain the clarity of the original code, but avoid the use of additional threads to perform asynchronous reads. Though, perhaps, the NetworkStream class was never designed for this sort of usage. Can anyone shed some light?
Update: Just want to clarify that I'm interested to see if the .NET framework has a solution that covers this use of NetworkStream (i.e. polling and avoiding blocking) - obviously it can be done; the NetworkStream could easily be wrapped in a supporting class that provides the functionality. It just seemed strange that the framework essentially requires you to use threads to avoid blocking on NetworkStream.Read, or, to peek on the socket itself to check for disconnections - almost like it's a bug. Or a potential lack of a feature. ;)
Is the server expecting to be sent multiple objects over the same connection? IF so I dont see how this code will work, as there is no delimiter being sent that signifies where the first object starts and the next object ends.
If only one object is being sent and the connection closed after, then the original code would work.
There has to be a network operation initiated in order to find out if the connection is still active or not. What I would do, is that instead of deserializing directly from the network stream, I would instead buffer into a MemoryStream. That would allow me to detect when the connection was lost. I would also use message framing to delimit multiple responses on the stream.
MemoryStream ms = new MemoryStream();
NetworkStream ns = client.GetStream();
BinaryReader br = new BinaryReader(ns);
// message framing. First, read the #bytes to expect.
int objectSize = br.ReadInt32();
if (objectSize == 0)
break; // client disconnected
byte [] buffer = new byte[objectSize];
int index = 0;
int read = ns.Read(buffer, index, Math.Min(objectSize, 1024);
while (read > 0)
{
objectSize -= read;
index += read;
read = ns.Read(buffer, index, Math.Min(objectSize, 1024);
}
if (objectSize > 0)
{
// client aborted connection in the middle of stream;
break;
}
else
{
BinaryFormatter bf = new BinaryFormatter();
using(MemoryStream ms = new MemoryStream(buffer))
{
object o = bf.Deserialize(ns);
ReceiveMyObject(o);
}
}
Yeah but what if you lose a connection before getting the size? i.e. right before the following line:
// message framing. First, read the #bytes to expect.
int objectSize = br.ReadInt32();
ReadInt32() will block the thread indefinitely.