How to check the ERROR if the client is trying to connect to a absent server?
my code!
//Server
void Start () {
NetworkServer.Listen(13044);
}
//Client
NetworkClient thisclient = new NetworkClient ();
thisclient.Connect ("127.0.0.1", 13044);
thisclient.RegisterHandler(MsgType.Error, errortest);
thisclient.RegisterHandler (MsgType.Disconnect, dctest);
void errortest(NetworkMessage netMsg){
var errorMsg = netMsg.ReadMessage<ErrorMessage>();
Debug.Log("Error:" + errorMsg.errorCode);}
void dctest(NetworkMessage netMsg){
//if I run the client while the server is not present, its goes here instead of errortest
}
You are using ReadMessage with ErrorMessage, but ErrorMessage is only valid in Error messages (OnError).
Your dctest function is triggered on disconnection, not on error.
Disconnect is a special MsgType (see https://docs.unity3d.com/ScriptReference/Networking.MsgType.html) that (if I remember) doesn't contain any data.
So to answer your question : you already have the result. Everything is in netMsg.
https://docs.unity3d.com/Manual/UNetMessages.html
The ReadMessage function is mostly used with your own NetworkMessages, when you wand to send/read custom data.
Related
Why can not I read bytes from the TcpClient in C#?
Here is the error I am getting:
Unable to read data from the transport connection: An established connection was aborted by the software in your host machine.
Here is how I start my TcpClient:
public static async void Start()
{
TcpListener server = null;
try
{
server = new TcpListener(IPAddress.Loopback, 13000);
server.Start();
var client = await server.AcceptTcpClientAsync();
var stream = client.GetStream();
var bytes = Convert.FromBase64String("ABCD");
await stream.WriteAsync(bytes, 0, bytes.Length);
client.Close();
}
catch (Exception e)
{
throw;
}
finally
{
if(server != null)
{
server.Stop();
}
}
}
Here is how I run a request to the TcpClient:
try {
var response = (new HttpClient()).GetByteArrayAsync("http://localhost:13000").Result;
return Convert.ToBase64String(response);
} catch(Exception e) {
throw;
}
The return Convert.ToBase64String(response); line is never reached. While I see the quoted above error message inside the Exception e if I hit a breakpoint on the throw line.
Also, during debug the Start() method completes just fine. I.e. it starts, then wait for a request, gets a request, writes to the TclClient and at the end runs the server.Stop(); command.
I am expecting my code to work, because I took it and modified from the official documentation over here.
I tried to check out a few resources which would tackle my exception, but none of them did help.
E.g. I tried to use the question.
First answer tells nothing useful actually, but just plays around with words and at the end states that one can do nothing about the exception (please, correct me if I am missing a point in the answer).
And the second answer tells an impossible in my case problem. Because, I am sure there is nothing running on the 13000 port.
Your client code is using HttpClient, which sends an HTTP request and expects an HTTP response. But your server is not an HTTP server, it is just a plain TCP server, so the client is likely to fail and forcibly close the connection when it doesn't receive a properly formatted HTTP response.
The "official documentation" whose example you modified is not using HttpClient at all, it is using TcpClient instead.
If you want to use HttpClient in your client, then you should use HttpListener instead of TcpListener in your server.
I use SignalR in an Angular app. When I destroy component in Angular I also want to stop connection to the hub. I use the command:
this.hubConnection.stop();
But I get an error in Chrome console:
Websocket closed with status code: 1006
In Edge: ERROR Error: Uncaught (in promise): Error: Invocation canceled due to connection being closed. Error: Invocation canceled due to connection being closed.
It actually works and connection has been stopped, but I would like to know why I get the error.
This is how I start the hub:
this.hubConnection = new HubConnectionBuilder()
.withUrl("/matchHub")
.build();
this.hubConnection.on("MatchUpdate", (match: Match) => {
// some magic
})
this.hubConnection
.start()
.then(() => {
this.hubConnection.invoke("SendUpdates");
});
EDIT
I finally find the issue. Its caused by change streams from Mongo. If I remove the code from SendUpdates() method then OnDisconnected is triggered.
public class MatchHub : Hub
{
private readonly IMatchManager matchManager;
public MatchHub(IMatchManager matchManager)
{
this.matchManager = matchManager;
}
public async Task SendUpdates() {
using (var changeStream = matchManager.GetChangeStream()) {
while (changeStream.MoveNext()) {
var changeStreamDocument = changeStream.Current.FullDocument;
if (changeStreamDocument == null) {
changeStreamDocument = BsonSerializer.Deserialize<Match>(changeStream.Current.DocumentKey);
}
await Clients.Caller.SendAsync("MatchUpdate", changeStreamDocument);
}
}
}
public override async Task OnDisconnectedAsync(Exception exception)
{
await base.OnDisconnectedAsync(exception);
}
}
Method GetChangeStream from the manager.
ChangeStreamOptions options = new ChangeStreamOptions() { FullDocument = ChangeStreamFullDocumentOption.UpdateLookup };
var watch = mongoDb.Matches.Watch(options).ToEnumerable().GetEnumerator();
return watch;
But I don't know how to fix it.
This can be for many reasons but i think it is most likely this one:
I think this is because of how the server is handling the connected / disconnected events. I can't say for sure but the connection closing needs to handled correctly on the server also with code. Try overriding the built in On Connected /Disconnected methods on the server and see. My assumption only is that you're closing it but the server isn't closing properly and therefore not relaying the proper closed response.
found as a comment at : getting the reason why websockets closed with close code 1006
Where you don't need to change the connection/disconection because evrything works fine. But as an answer this one is the most likely.
It throws error because the callback doesn't get clear properly.
And it is caused by the return data from websocket.
normally it should return like
However, for some reason it might return something like
the very last response breaking into 2 pieces
And that causes the issue.
I don't think there is a way to bypass this without changing the source code.
I reported this on github repo as well at here
It turns out that I can just utilize invocation response to notify client to stop the hub. So it doesn't trigger racing issue.
I have a StreamSocket in UWP and I send my messages like this using a DataWriter object using the StoreAsync() method:
public static async Task<bool> SendNetworkMessage(NetworkMember member, NetworkMessage message)
{
DataWriter writer = member.DataWriter;
//Check that writer is not null
if (writer != null)
{
try
{
//Serialize Message
string stringToSend = SerializeObject<NetworkMessage>(message);
//Send Message Length
writer.WriteUInt32(writer.MeasureString(stringToSend));
//Send Message
writer.WriteString(stringToSend);
await writer.StoreAsync();
return true;
}
catch (Exception e)
{
Debug.WriteLine("DataWriter failed because of " + e.Message);
Debug.WriteLine("");
Disconnect(member);
OnMemberDisconnectedEvent(member);
return false;
}
}
else { return false; }
}
All is well, the only problem is that I don't know if a connection went down.
Now I want to check my connection using a DispatcherTimer like this:
private static async void NetworkTimer_Tick(object sender, object e)
{
foreach (NetworkMember member in networkMemberCollection)
{
if (member.Connected == true && member.Disconnecting == false)
{
await SendNetworkMessage(member, new PingMessage());
}
}}
However, this is causing timing issues which is causing ObjectDisposedExceptions on the DataWriter. It seems that the DispatcherTimer thread cannot use the StreamSocket when I send a message from a different thread. My question is: How can I make sure the Ping is sent each time but that SendNetworkMessage operations are done in order instead of overlapping?
Thanks
It seems that the DispatcherTimer thread cannot use the StreamSocket when I send a message from a different thread.
How can I make sure the Ping is sent each time but that SendNetworkMessage operations are done in order instead of overlapping?
It's possible, and I think your code using foreach and await operation can ensure the work of sending message in order.
the only problem is that I don't know if a connection went down.
If you want to know if the connection went down, you can refer to Handling WinRT StreamSocket disconnects (both server and client side).
I have created an application for FIX transactions using QuickFIX c++ API. The application is connecting to the server but the server sends "Provide UserName<553>" message. I looked for and result and found that i need to add username and password to the toAdmin method created this following code to in order to achieve that
void Application::toAdmin( FIX::Message& message, const FIX::SessionID& sessionID)
{
if (FIX::MsgType_Logon == message.getHeader().getField(FIX::FIELD::MsgType))
{
FIX44::Logon& logon_message = dynamic_cast<FIX44::Logon&>(message);
logon_message.setField(FIX::Username("my_username"));
logon_message.setField(FIX::Password("my_password"));
}
}
But then it throws and Exception. Please suggest what to do
remove this line and exception is handled
FIX44::Logon& logon_message = dynamic_cast<FIX44::Logon&>(message);
after that Put it
message.setField(FIX::Username("my_username"));
```````
message.setField(FIX::Password("my_password"));
I'm having an issue using sockets in flash builder 4. The code below sends a set of bytes to a receiving c# sockerServer. If I dismiss the error I get in flash builder manually, the bytes are sent fine and all comes across as it should on 127.0.0.1:10. Now if I could just get the same results without an error being displayed in Flex.
So, I have two questions:
1) Why does it return an error when I try to close the socket? See closeConnection() below for context. I tried flushing it just before which didn't help.
2) Why is nothing sent when I use socket.flush()?
package
{
import flash.events.IOErrorEvent;
import flash.net.Socket;
import flash.utils.ByteArray;
public class socketClient
{
private var socket:Socket;
public function openConnection(address:String, port:int):void
{
if (socket != null && socket.connected)
socket.close();
socket = new Socket();
try {
socket.connect( address, port );
}
catch( e:Error ) { }
}
public function sendProtocol(p:socketProtocol):void {
//p.serialize() gets me a bunch of bytes in a ByteArray
var buffer:ByteArray = p.serialize();
socket.writeBytes(buffer, 0, buffer.length);
//Nothing happens when I flush
socket.flush();
}
public function closeConnection():void {
//As soon as I get to socket.close(), I get this
//"Unhandled IOErrorEvent:. text=Error #2031: Socket Error."
socket.close();
}
}
}
I use the class like this:
var socket:socketClient = new socketClient();
//works fine, I see the connection on the server
socket.openConnection("127.0.0.1", 10);
//no errors, but nothing sent
socket.sendProtocol(protocol);
//returns the error. (if manually dismissed, data is sent)
socket.closeConnection();
I finally solved it after hammering this one since I posted the question.
I had to add a
socket.addEventListener(flash.events.Event.CLOSE, closeHandler)
and do the socket.close() from there.