I have got an requirement to connect XMPP server using Java API Smack and further make send message/receive message.
I tried with Smack API (4.1.8) and I am getting errors (find errors below).
Note: both host and port are opened.
Code:`public class Sender {
public static void main(String a[]) throws NoResponseException,XMPPException,
InterruptedException, SmackException, IOException
{
// Create the configuration for this new connection
XMPPTCPConnectionConfiguration.Builder configBuilder = XMPPTCPConnectionConfiguration.builder();
configBuilder.setUsernameAndPassword("user", "******");
configBuilder.setResource("work");
configBuilder.setServiceName("HOstname");
configBuilder.setSocketFactory(SSLSocketFactory.getDefault());
configBuilder.setSecurityMode(SecurityMode.required);
configBuilder.setCompressionEnabled(true);
configBuilder.setHost("thingsociety.im");
configBuilder.setDebuggerEnabled(true);
configBuilder.setPort(5222);
System.out.println("Connected1..............");
XMPPTCPConnection connection = new XMPPTCPConnection(configBuilder.build());
// Connect to the server
try {
System.out.println("Connected2..............");
connection.setPacketReplyTimeout(100000);
connection.connect();
System.out.println("Connected3..............");
// Log into the server
connection.isConnected();
connection.login();
System.out.println("Connected4..............");
}
catch (XMPPException | SmackException | IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
System.out.println(e.getMessage());
}
}
}
Error: No response received within reply timeout. Timeout was 100000ms (~100s). Used filter: No filter used or filter was 'null'.
org.jivesoftware.smack.SmackException$NoResponseException: No response received within reply timeout. Timeout was 100000ms (~100s). Used filter: No filter used or filter was 'null'
So basicly something (local firewall or on your gateway) is blocking outgouing communications OR configBuilder.setServiceName("HOstname"); service name (aka XMPP Domain) is wrong, maybe mispelled - especialy capital O looks like misspell to me.
I have just probe thingsociety.im:5222 and it is open so most probably it is a firewall issue.
Another one could be unhandeld, low level error on server side.
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.
We have 2 UWP apps. One app shares data to the other app through StreamSocket. The server app will send data to client app. There will be 30-40 or more devices running the client app and connecting to the server's socket to receive data.
When we test with one client app, all the data sharing happens without any issue. But when we started testing with about 10 devices using the client app, sometimes some apps don't receive data. And there seems to be an error saying A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond
In general it get shared to most of the devices, but few fails sometimes randomly. What could be the reason for this? Is there a connection limit to connect to a socket with given IP and port using Stream Socket?
Here is some parts of our code. Please let me know what we have to correct here to avoid getting that error.
Server side
public async Task StartServer(string serverIp, string serverPort)
{
try
{
HostName serverAddress = new HostName(serverIp);
//Create a StreamSocketListener to start listening for TCP connections.
StreamSocketListener socketListener = new StreamSocketListener();
//Hook up an event handler to call when connections are received.
socketListener.ConnectionReceived += SocketListener_ConnectionReceived;
//Start listening for incoming TCP connections on the specified port.
await socketListener.BindEndpointAsync(serverAddress, serverPort);
}
catch (Exception e)
{
}
}
private async void SocketListener_ConnectionReceived(StreamSocketListener sender, StreamSocketListenerConnectionReceivedEventArgs args)
{
try
{
await Task.Run(() => ShareFile(args.Socket));
}
catch (Exception e)
{
}
}
Client side
public async Task ServerConnect(string serverIP, string serverPort)
{
try
{
HostName serverAddress = new HostName(serverIP);
StreamSocket socket = new StreamSocket();
socket.Control.KeepAlive = false;
// Connect to the server.
await socket.ConnectAsync(serverAddress, serverPort, SocketProtectionLevel.PlainSocket);
}
catch (Exception e)
{
}
}
Also would like to get these clarified
-What is the difference between BindServiceNameAsync and BindEndpointAsync? Most examples seems to use the first one. When should we use the second one?
-If we call sender.Dispose(); in SocketListener_ConnectionReceived, will that affect the other clients trying to join the same socket?
-In the ShareFile() function, if we close args.Socket() after sending data, can it close the socket before the client actually read the data from that side?
I have the following architecture in use:
- [Client] - The enduser connecting to our service.
- [GameServer] - The game server on which the game is running.
- [GameLobby] - A server that is responsible for matching Clients with a GameServer.
If we have for example 4 Clients that want to play a game and get matched to a GameLobby, then the first time all these connection succeeds properly.
However when they decide to rematch, then one of the Clients will not properly connect.
The connection between all the Clients and the GameServer happens simultaneously.
Clients that rematch first removes their current connection with the GameServer and head into the lobby again.
This connection will succeed, no errors are thrown. Even using a ChannelFuture it shows that the client connection was made properly, the following values are retrieved to show that the client thinks the connection was correct:
- ChannelFuture.isSuccess() = True
- ChannelFuture.isDone() = True
- ChannelFuture.cause() = Null
- ChannelFuture.isCancelled() = False
- Channel.isOpen() = True
- Channel.isActive() = True
- Channel.isRegistered() = True
- Channel.isWritable() = True
Thus the connection was properly made according to the Client. However on the GameServer at the SimpleChannelInboundHandler, the method ChannelRegistered/ChannelActive is never called for that specific Client. Only for the other 3 Clients.
All the 4 Clients, the GameServer, and the Lobby are running on the same IPAddress.
Since it only happens when (re)connecting again to the GameServer, I thought that is had to do with not properly closing the connection. Currently this is done through:
try {
group.shutdownGracefully();
channel.closeFuture().sync();
} catch (InterruptedException e) {
e.printStackTrace();
}
On the GameServer the ChannelUnregister is called thus this is working, and the connection is destroyed.
I have tried adding listeners to the ChannelFuture of the malfunctioning channel connection, however according to the channelFuture everything works, which is not the case.
I tried adding ChannelOptions to allow for more Clients queued to the server.
GameServer
The GameServer server is initialized as follow:
// Create the bootstrap to make this act like a server.
ServerBootstrap serverBootstrap = new ServerBootstrap();
serverBootstrap.group(bossGroup)
.channel(NioServerSocketChannel.class)
.childHandler(new ChannelInitialisation(new ClientInputReader(gameThread)))
.option(ChannelOption.SO_BACKLOG, 1000)
.childOption(ChannelOption.SO_KEEPALIVE, true)
.childOption(ChannelOption.TCP_NODELAY, true);
bossGroup.execute(gameThread); // Executing the thread that handles all games on this GameServer.
// Launch the server with the specific port.
serverBootstrap.bind(port).sync();
The GameServer ClientInputReader
#ChannelHandler.Sharable
public class ClientInputReader extends SimpleChannelInboundHandler<Packet> {
private ServerMainThread serverMainThread;
public ClientInputReader(ServerMainThread serverMainThread) {
this.serverMainThread = serverMainThread;
}
#Override
public void channelRegistered(ChannelHandlerContext ctx) throws Exception {
System.out.println("[Connection: " + ctx.channel().id() + "] Channel registered");
super.channelRegistered(ctx);
}
#Override
protected void channelRead0(ChannelHandlerContext ctx, Packet packet) {
// Packet handling
}
}
The malfunction connection is not calling anything of the SimpleChannelInboundHandler. Not even ExceptionCaught.
The GameServer ChannelInitialisation
public class ChannelInitialisation extends ChannelInitializer<SocketChannel> {
private SimpleChannelInboundHandler channelInputReader;
public ChannelInitialisation(SimpleChannelInboundHandler channelInputReader) {
this.channelInputReader = channelInputReader;
}
#Override
protected void initChannel(SocketChannel ch) throws Exception {
ChannelPipeline pipeline = ch.pipeline();
// every packet is prefixed with the amount of bytes that will follow
pipeline.addLast(new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE, 0, 4, 0, 4));
pipeline.addLast(new LengthFieldPrepender(4));
pipeline.addLast(new PacketEncoder(), new PacketDecoder(), channelInputReader);
}
}
Client
Client creating a GameServer connection:
// Configure the client.
group = new NioEventLoopGroup();
Bootstrap b = new Bootstrap();
b.group(group)
.channel(NioSocketChannel.class)
.option(ChannelOption.TCP_NODELAY, true)
.handler(new ChannelInitialisation(channelHandler));
// Start the client.
channel = b.connect(address, port).await().channel();
/* At this point, the client thinks that the connection was succesfully, as the channel is active, open, registered and writable...*/
ClientInitialisation:
public class ChannelInitialisation extends ChannelInitializer<SocketChannel> {
private SimpleChannelInboundHandler<Packet> channelHandler;
ChannelInitialisation(SimpleChannelInboundHandler<Packet> channelHandler) {
this.channelHandler = channelHandler;
}
#Override
public void initChannel(SocketChannel ch) throws Exception {
// prefix messages by the length
ch.pipeline().addLast(new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE, 0, 4, 0, 4));
ch.pipeline().addLast(new LengthFieldPrepender(4));
// our encoder, decoder and handler
ch.pipeline().addLast(new PacketEncoder(), new PacketDecoder(), channelHandler);
}
}
ClientHandler:
public class ClientPacketHandler extends SimpleChannelInboundHandler<Packet> {
#Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
super.channelActive(ctx);
System.out.println("Channel active: " + ctx.channel().id());
ctx.channel().writeAndFlush(new PacketSetupClientToGameServer());
System.out.println("Sending setup packet to the GameServer: " + ctx.channel().id());
// This is successfully called, as the client thinks the connection was properly made.
}
#Override
protected void channelRead0(ChannelHandlerContext ctx, Packet packet) {
// Reading packets.
}
}
I expect that the Client could connect properly to the server. Since the other Clients are properly connecting and the client could previously connect just fine.
TL;DR: When multiple Clients try to create a new match, there is a possibility that one, possibly more, Client(s) will not connect properly with the server, after the previous connection was closed.
For some that struggle with this issue in some way or another.
I did a workaround that allows me to continue even tho there is still a bug inside the Netty framework (as far as I am concerned). The workaround is quite simple just create a connection pool.
My solution uses a maximum of five connections inside the connection pool. If one of the connection gets no reply from the GameServer, then it is not that big of a deal, since there are four others that will have a high chance of succeeding. I know this is a bad workaround, but I could not find any information on this issue. It works and only gives a maximum delay of 5 seconds (each retry takes a second)
I'm doing a performance test against a Spring Cloud application. When number of concurrent users exceeds 150, it starts to give "Forwarding error"
{"timestamp":1458685370986,"status":500,"error":"Internal Server Error","exception":"com.netflix.zuul.exception.ZuulException","message":"Forwarding error"}
Which parameter I should adjust to get rid of the error?
You should post your logs for the error, without that we can only guess what the exact error is. As Forwarding error reported by ZuulExcetption is a generic error.
See this link for the RibbonRoutingFilter.forward() method which actually reports this error. I'm adding the code here for the backup.
private HttpResponse forward(RestClient restClient, String service, Verb verb, String uri, Boolean retryable,
MultiValueMap<String, String> headers, MultiValueMap<String, String> params,
InputStream requestEntity) throws Exception {
Map<String, Object> info = this.helper.debug(verb.verb(), uri, headers, params,
requestEntity);
RibbonCommand command = new RibbonCommand(service, restClient, verb, uri, retryable,
headers, params, requestEntity);
try {
HttpResponse response = command.execute();
this.helper.appendDebug(info, response.getStatus(),
revertHeaders(response.getHeaders()));
return response;
}
catch (HystrixRuntimeException ex) {
info.put("status", "500");
if (ex.getFallbackException() != null
&& ex.getFallbackException().getCause() != null
&& ex.getFallbackException().getCause() instanceof ClientException) {
ClientException cause = (ClientException) ex.getFallbackException()
.getCause();
throw new ZuulException(cause, "Forwarding error", 500, cause
.getErrorType().toString());
}
throw new ZuulException(ex, "Forwarding error", 500, ex.getFailureType()
.toString());
}
}
As you can see that only viable place where the error can be generated is in command.execute(), where command is an instance of HystrixCommand. Here is a link for the execute() method in HystrixCommand.
Below is the code for backup.
public R execute() {
try {
return queue().get();
} catch (Exception e) {
throw decomposeException(e);
}
}
Here the queue() is a Future instance
Most common error that can occur with the Future is a timeout exception. Since here Future instance queue() is not bound by any timetout value, it can go on waiting for ever.
However most of the time API which make use of Future have a thread monitoring the time they take and they interrupt it after a certain period of time. Same is done by Ribbon.
If yours indeed is a timeout issue then an easy solution is to increase Ribbon timeout value by using following property.
ribbon.ReadTimeout=10000
//or
<client-name>.ribbon.ReadTimeout=10000
Time out majorly can occur if the tomcat server which hosts the service which is proxied by the Zuul has too much load. It's whole thread pool is exhausted thus resulting in the next requests having to wait for long time.
This can probably be alleviated by change the number of threads that your service tomcat has by using following property.
server.tomcat.max-threads=0
By default it's set to 0, which leaves it to the embedded server's default. In tomcat's case it's 200. See the reference maxThreads property in tomcat.
Note: To increase the thread pool size we have to make sure that the machine has that capacity to provide resources if that many threads were to be in execution simultaneously.
I have some code in a test as follows:
#Test
public void testRetrieveMongoDBFailUnkownHost()
{
//Set up test port and host on DSMongo
MyMongo mongoTest = new MyMongo();
mongoTest.setHost("failure");
mongoTest.setPort("0");
//attempt to make the connection
try
{
mongoTest.attemptMongoConnection();
assertTrue(false);
}
catch (Exception e)
{
assertEquals("Incorrect error message received: " + e.getMessage(),"Error (3013) : Unknown database host.", e.getMessage());
}
}
And the attempt MongoConnection() method runs the new Mongo(host, port) method which should fail with an unknown host exception. It isn't failing on my machine (no matter what string I put in instead of failure) but it is failing on my colleagues machine. So the test fails on my machine and passes on his (i.e. he gets the exception). Any ideas cause I am stumped!
Thanks
Paul
EDIT: The code in the attempt Connection Method is
*/
public static void attemptMongoConnection() throws MYException
{
try {
singleMongo = new Mongo(getHost(), getPort());
Logger.debug("Retrieved Mongo database from " + host);
} catch (UnknownHostException e) {
Logger.error("Unknown Host Exception", e);
throw new MYException(MYMessage.MY_UNKNOWN_HOST);
} catch (MongoException e) {
Logger.error("Mongo error", e);
throw new MYException(MYMessage.DS_MONGO_ERROR);
}
}
where singleMOngo is a Mongo variable and the getHost and getPort are the ones we have set (.e. failure and 0).
I have found this was a problem with the DNS somewhere. When I ran it at home (from where I originally made the post) it failed and seems to hav been resolving the name of "failure" so when I instead entered something like "localhost_123" it works perfectly.
I have come into the office this morning and it works with "failure" again. Doing some further digging it seems therefore that my router or something at home is resolving "failure" to an address it is aware of which is not present on the network here in the office.
Thanks for all those who looked at this. Very bizarre.