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is Eclipse/Californium CoAP observer much slower than Aiocoap observer?

I'm trying to build a system in which I can connect some devices to a server over the internet.
I want to stream some data over CoAP (10-30FPS), frame size = 3KB.
Firstly, I used Aiocoap, it sends up to 100FPS but uses too much CPU,
requests are NON, got low lose rate in Aiocoap,
while Eclipse/Californium could not send more than 3FPS,
when i use higher FPS, either I receive only the first block of each message or receiving nothing, also not ordered most of the times.
I was wondering if this is the real performance of Californium or am I using it in a wrong way?
I will share some code:
server.java
static class CoapObserverServer extends CoapResource {
int i = -1;
public CoapObserverServer() {
super("alarm");
setObservable(true); // enable observing
setObserveType(Type.NON); // configure the notification type to CONs
getAttributes().setObservable(); // mark observable in the Link-Format
System.out.println(this);
// schedule a periodic update task, otherwise let events call changed()
//new Timer().schedule(new UpdateTask(), 0, 1000/2);
}
private class UpdateTask extends TimerTask {
#Override
public void run() {
changed(); // notify all observers
}
}
#Override
public void handleGET(CoapExchange exchange) {
// the Max-Age value should match the update interval
exchange.setMaxAge(1);
//++i;
int leng = 2000;
String s = "" + i + "-" + fillString('X', leng - 1 - Integer.toString(i).len>
exchange.respond(s);
}
public static String fillString(char fillChar, int count){
// creates a string of 'x' repeating characters
char[] chars = new char[count];
while (count>0) chars[--count] = fillChar;
return new String(chars);
}
#Override
public void handleDELETE(CoapExchange exchange) {
delete(); // will also call clearAndNotifyObserveRelations(ResponseCode.NOT_>
exchange.respond(ResponseCode.DELETED);
}
#Override
public void handlePUT(CoapExchange exchange) {
exchange.accept();
int format = exchange.getRequestOptions().getContentFormat();
if (format == MediaTypeRegistry.TEXT_PLAIN) {
// ...
String plain = exchange.getRequestText();
try{
i = Integer.valueOf(plain);
} catch(NumberFormatException ex){
System.out.println("error converting string"+ plain);
}
exchange.respond(ResponseCode.CHANGED);
changed(); // notify all observers
}
}
Observer.java
private static final File CONFIG_FILE = new File("Californium3.properties");
private static final String CONFIG_HEADER = "Californium CoAP Properties file for client";
private static final int DEFAULT_MAX_RESOURCE_SIZE = 2 * 1024 * 1024; // 2 MB
private static final int DEFAULT_BLOCK_SIZE = 512;
static {
CoapConfig.register();
UdpConfig.register();
}
private static DefinitionsProvider DEFAULTS = new DefinitionsProvider() {
#Override
public void applyDefinitions(Configuration config) {
config.set(CoapConfig.MAX_RESOURCE_BODY_SIZE, DEFAULT_MAX_RESOURCE_SIZE);
config.set(CoapConfig.MAX_MESSAGE_SIZE, DEFAULT_BLOCK_SIZE);
config.set(CoapConfig.PREFERRED_BLOCK_SIZE, DEFAULT_BLOCK_SIZE);
}
};
private static class AsynchListener implements CoapHandler {
#Override
public void onLoad(CoapResponse response) {
System.out.println( response.getResponseText() );
}
#Override
public void onError() {
System.err.println("Error");
}
}
/*
* Application entry point.
*/
public static void main(String args[]) {
Configuration config = Configuration.createWithFile(CONFIG_FILE, CONFIG_HEADER, DEFAULTS);
Configuration.setStandard(config);
URI uri = null; // URI parameter of the request
if (args.length > 0) {
// input URI from command line arguments
try {
uri = new URI(args[0]);
} catch (URISyntaxException e) {
System.err.println("Invalid URI: " + e.getMessage());
System.exit(-1);
}
CoapClient client = new CoapClient(uri);
client.useNONs();
// observe
AsynchListener asynchListener = new AsynchListener();
CoapObserveRelation observation = client.observe(asynchListener);
// User presses ENTER to exit
System.out.println("Press ENTER to exit...");
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
try { br.readLine(); } catch (IOException e) { }
System.out.println("Exiting...");
observation.proactiveCancel();
}
So i'm controlling the FPS by sending PUT requests with a server that has a counter 0-50.

Not sure, what your doing.
That seems to be wired and not related to RFC7252 nor RFC7641.
CoAP is designed for REST, I don't see any benefit in using it for video streaming.
Using Eclipse/Californium on a Intel n6005 with 16GB RAM, the CoAP/DTLS server runs on about 60000 requests/second. The benchmark uses 2000 clients in parallel.
See also Eclipse/Californium - Benchmarks j5005
Using only one client with CON requests, the performance is mainly limited by the RTT. 30 requests/second should work, if that RTT is accordingly small.
Using NON requests doesn't really help. CoAP RFC7252 defines two layers, a messaging layer and an application layer. NON affects only the messaging layer, but a NON request will wait for it's response, if NSTART-1 should be used.
If your RTT is the issue, you may try to escape that either using requests with "No Server Response" (RFC7967) or multiple NON responses (RFC7641). The first is not intended for fast requests, the second is more a work-around of the initial statement, that CoAP is REST not video-streaming.
So, what is your RTT?

grpc Client-Streaming Java Client gets io.grpc.StatusRuntimeException: UNAVAILABLE: HTTP status code 503

I have a grpc Nodejs server behind a HAproxy and client-streaming rpc java maven.
When I run the java client it return an error:
io.grpc.StatusRuntimeException: UNAVAILABLE: HTTP status code 503
invalid content-type: text/html headers:
Metadata(:status=503,cache-control=no-cache,content-type=text/html)
DATA-----------------------------
503 Service Unavailable No server is available to handle this request.
I already test a rpc client streaming with Nodejs and it worked.
My java client code:
public class App {
public static void main(String[] args) throws InterruptedException {
WebRTCStats stat = WebRTCStats.newBuilder().setUserId("abc").build();
SendWebRTCStats(stat);
}
public static void SendWebRTCStats(WebRTCStats stat) throws InterruptedException {
ManagedChannel channel = ManagedChannelBuilder.forTarget("example.com:443").useTransportSecurity()
.build();
ClientGrpc.ClientStub stub = ClientGrpc.newStub(channel);
StreamObserver<Stat.Status> responseObserver = new StreamObserver<Stat.Status>() {
#Override
public void onNext(Stat.Status status) {
}
#Override
public void onError(Throwable t) {
t.printStackTrace();
}
#Override
public void onCompleted() {
System.out.print("complete");
}
};
StreamObserver<WebRTCStats> requestObserver = stub.sendWebRTCStats(responseObserver);
try {
// Send numPoints points randomly selected from the features list.
requestObserver.onNext(stat);
// Sleep for a bit before sending the next one.
} catch (RuntimeException e) {
// Cancel RPC
requestObserver.onError(e);
throw e;
}
// Mark the end of requests
requestObserver.onCompleted();
// Receiving happens asynchronously
}
}
My NodeJS server:
const PROTO_PATH = './stat.proto';
const grpc = require('grpc');
const protoLoader = require('#grpc/proto-loader');
const fs = require('fs');
const tcp = require('./using.js');
let packageDefinition = protoLoader.loadSync(PROTO_PATH);
let protoDescriptor = grpc.loadPackageDefinition(packageDefinition);
const server = new grpc.Server();
server.addService(protoDescriptor.Client.service, {
SendWebRTCStats: async (call, callback) => {
call.on('data', value => {
console.log(value);
tcp.sendLog("test", value);
});
call.on('end', () => {
callback(null, { status: 'success' });
})
},
});
let credentials = grpc.ServerCredentials.createSsl(
fs.readFileSync('ca.cer'), [{
cert_chain: fs.readFileSync('cer.crt'),
private_key: fs.readFileSync('cer_key.key')
}], false);
server.bind("0.0.0.0:443", credentials);
console.log("Server running at 443");
server.start();
Can this problem occurs by different implementations of different libraries of language in GRPC?

so apperently i changed forTarget("example.com) and it worked. I shouldnt specify port for it.

Java netty rxtx pipeline blocks after writeAndFlush()

I'm currently trying to achieve a somewhat stable connection between a micro-controller and a Java-application using netty 4.0.44.Final and rxtx. From time to time the controller asks for a time-stamp, otherwise it is just forwarding sensor data to my application. The application is able to receive as many packages as I want to until i call writeAndFlush() somewhere in the pipeline (i.e. answering a time-request). The pipeline correctly writes data on the outputstream (when writeAndFlush() is called) and from that point onwards my application is never receiving data again and I have no idea why.
public class WsnViaRxtxConnector extends AbstractWsnConnector{
private static final Logger LOG = LoggerFactory.getLogger(WsnViaRxtxConnector.class);
private String port;
private Provider<MessageDeserializer> deserializerProvider;
private ChannelFuture channelFuture;
public ChannelKeeper keeper;
#Inject
public WsnViaRxtxConnector(Provider<MessageDeserializer> deserializerProvider, ChannelKeeper keeper) {
this.deserializerProvider = deserializerProvider;
this.port = Configuration.getConfig().getString("rest.wsn.port");
this.keeper = keeper;
System.setProperty("gnu.io.rxtx.SerialPorts", this.port);
}
#Override
protected void run() throws Exception
{
EventLoopGroup group = new OioEventLoopGroup();
//final EventExecutorGroup group2 = new DefaultEventExecutorGroup(1500);
try {
Bootstrap b = new Bootstrap();
b.group(group)
.channel(RxtxChannel.class)
.handler(new ChannelInitializer<RxtxChannel>() {
#Override
public void initChannel(RxtxChannel ch) throws Exception {
ch.pipeline().addLast(new DleStxEtxFrameDecoder(), new DleStxEtxFrameEncoder());
ch.pipeline().addLast(new IntegrityCheck(),new IntegrityCalculation());
ch.pipeline().addLast(new AesCcmDecrypter(),new AesCcmEncrypter());
ch.pipeline().addLast(deserializerProvider.get(),new MessageSerializer());
ch.pipeline().addLast(new TimeStampJockel());
}
})
.option(RxtxChannelOption.BAUD_RATE, 19200);
ChannelFuture f = b.connect(new RxtxDeviceAddress(this.port)).sync();
f.channel().closeFuture().sync();
} finally {
group.shutdownGracefully();
}
}
The handlers are all pretty much standard implementations and seem to work when receiving packages only. The pipeline should first generate an object from the raw data, checkCRC, decrypt, deserialize and then compute some logic (aka generate a time-response).
public class TimeStampJockel extends ChannelInboundHandlerAdapter{
private static final Logger LOG = LoggerFactory.getLogger(TimeStampJockel.class);
private EventBus bus;
private ChannelKeeper keeper;
#Inject
public TimeStampJockel(){
this.bus = GlobalEventBus.getInstance();
this.keeper = keeper;
}
#Override
public void channelRead(ChannelHandlerContext ctx, Object msg){
LOG.debug("Creating packet from received data");
RawPacket raw = (RawPacket)msg;
//EventExecutor ex = ctx.executor();
//LOG.debug("inexecutor.EventLoop(1):" + ex.inEventLoop());
//keeper.addChannelHandlerContext(raw.getSource(),ctx);
ByteBuf buf = raw.getContent();
LOG.debug("\tBuffer: {}", HelperFunctions.getBufferAsHexString(buf));
UnsignedLong mac = UnsignedLong.fromLongBits(21);
while(buf.readerIndex()<buf.writerIndex())
{
int type = buf.readShort();
int length = buf.readShort();
ByteBuf value = buf.readBytes(length);
if(PacketType.getEnum(type).equals(PacketType.MAC))
{
mac = UnsignedLong.valueOf(value.readLong());
}
else
{
AbstractPacket packet = PacketFactory.createPacket(PacketType.getEnum(type), raw.getVersion(), raw.getPacketType(), raw.getSource(), raw.getSource(), raw.getDestination(), mac, value);
if(packet instanceof TimeReqPacket) {
TimeReqPacket timeReqPacket = (TimeReqPacket) packet;
Duration d = HelperFunctions.timeSinceYear2000();
TimeRespPacket newPacket = new TimeRespPacket(Constants.PROTOCOL_VERSION, PacketType.TIME_RESP.getValue(), packet.getGatewayAdr(),UnsignedLong.valueOf(Configuration.getConfig().getLong("rest.wsn.mac", Long.MAX_VALUE)),timeReqPacket.getMac(),timeReqPacket.getMac(),d.getStandardSeconds(),HelperFunctions.getMillisOfDuration(d));
ctx.write(newPacket);
} else {
bus.post(packet);
}
}
}
}
The received sensor data is pushed to a Guava-bus (unless its a time-request) and processed by other components. If the incoming package is a time-request-packet, the previously displayed component should generate a time-stamp-packet and writeAndFlush() is down the pipeline. Any ideas what may cause that issue? I'm pretty much out of ideas - I have been googling the last 10 hours without meaningful results and I have no unchecked resources left. I'm using ubuntu 16.04, thanks in advance.
[EDIT] I tried checking the ChannelFuture, by adding the following code-snippet to the last pipeline handler
ChannelFuture f = ctx.writeAndFlush(newPacket);
f.addListener(new ChannelFutureListener() {
#Override
public void operationComplete(ChannelFuture future) throws Exception {
if (!future.isSuccess()) {
LOG.error("Server failed to send message", future.cause());
future.channel().close();
}
}
[EDIT2] Found my error. It was a netty version conflict. I am working with multiple versions of netty in different projects and was using an older netty version (4.0.13) instead of netty 4.044.final. I have no idea what changed between those versions but I am glad that everything is working properly now.

Android app did not receive data from SignalR hub

I already read these topics:
how to use SignalR in Android
Android Client doesn't get data but .net client getting data from SignalR server
I write a simple chat system with Android that works with SignalR.
It is supposed to the clients send messages (by calling SendMessage method on the server) and the server should call the NewMessage method on the clients.
Here is my ChatHub class (simplified) written in C#.
public class ChatHub : Hub
{
// Store the clients connections Id
static readonly List<string> _connectedClients;
public override Task OnConnected()
{
// Keep connections id
// This section works fine and when the android device connects to the server,
// Its connection id will stored.
_connectedClients.Add(Context.ConnectionId)
//... other codes
}
public void SendMessage(string message)
{
foreach (var connectionId in _connectedClients)
{
// according to the logs
// android device connection id exists here
// and it works fine.
Clients.Client(connectionId).NewMessage(message);
}
}
}
When the android client connects to the server, On the OnConnected method, the connection id will be stored in the _connectedClients and it works fine.
In the SendMessage method of the ChatHub class, We have the android device connection id, and I'm sure that the android device is within the list
And here is my Andoird codes:
public class ChatActivity extends AppCompatActivity
{
// private fields
HubConnection connection;
HubProxy hub;
ClientTransport transport;
protected void onCreate(Bundle savedInstanceState) {
Logger logger = new Logger() {
#Override
public void log(String message, LogLevel logLevel) {
Log.e("SignalR", message);
}
};
Platform.loadPlatformComponent(new AndroidPlatformComponent());
connection = new HubConnection("192.168.1.100");
hub = connection.createHubProxy("chatHub"); // case insensitivity
transport = new LongPollingTransport(connection.getLogger());
// no difference when using this:
//transport = new ServerSentEventsTransport(connection.getLogger());
// this event never fired!
hub.subscribe(new Object() {
public void NewMessage(String message)
{
Log.d("<Debug", "new message received in subscribe"); // won't work!
}
}
// this event never fired!
hub.on("NewMessage", new SubscriptionHandler() {
#Override
public void run() {
Log.d("<Debug", "new message received in `on`"); // won't work!
}
});
// connect to the server that works fine.
SignalRFuture<Void> awaitConnection = connection.start(transport);
try {
awaitConnection.get(); // seems useless when using this or not!
}
catch (Exception ex) {
}
// this method works fine.
hub.invoke("sendMessage", "this is a test message to the server")
.done(new Action<Void>() {
#Override
public void run(Void aVoid) throws Exception {
Log.d("<Debug", "message sent."); // Works fine
}
});
}
}
In the above java code, invoking the sendMessage on the server works fine and the server get the messages.
But the only problem is that the hub.on(...) or hub.subscribe(...) events are never be called by the server.
In a simple description, My app can send message, but can not receive message from the others.
Any suggestion will be appreciated.

For the futures this is the way I finally achieved the answer (please first read the question android codes):
public class ChatActivity extends AppCompatActivity
{
// private fields
HubConnection connection;
HubProxy hub;
ClientTransport transport;
protected void onCreate(Bundle savedInstanceState) {
Logger logger = new Logger() {
#Override
public void log(String message, LogLevel logLevel) {
Log.e("SignalR", message);
}
};
Platform.loadPlatformComponent(new AndroidPlatformComponent());
connection = new HubConnection("192.168.1.100");
hub = connection.createHubProxy("chatHub"); // case insensitivity
/* ****new codes here**** */
hub.subscribe(this);
transport = new LongPollingTransport(connection.getLogger());
/* ****new codes here**** */
connection.start(transport);
/* ****new codes here**** */
/* ****seems useless but should be here!**** */
hub.subscribe(new Object() {
#SuppressWarnings("unused")
public void newMessage(final String message, final String messageId, final String chatId,
final String senderUserId, final String fileUrl, final String replyToMessageId) {
}
});
/* ********************** */
/* ****new codes here**** */
/* **** the main method that I fetch data from server**** */
connection.received(new MessageReceivedHandler() {
#Override
public void onMessageReceived(final JsonElement json) {
runOnUiThread(new Runnable() {
public void run() {
JsonObject jsonObject = json.getAsJsonObject();
Log.e("<Debug>", "response = " + jsonObject.toString());
}
});
}
});
/* ********************** */
}
}
!important note:
The priority of the codes is important. this is how I fix my problem in this topic.

You does not provider parameters in your client-side which should be same as your side-site. The code should be below:
hub.on("NewMessage", new SubscriptionHandler1<String>() {
#Override
public void run(String message) {
Log.d("<Debug", "new message received in `on`");
}
},String.class); //do not forget say the String class in the end

How Can I create,send and receive iq packets using smack(java)

I am connected to server(Xmpp)
but unable to send and receive packets at my psi client
Here is snippet of my code
POSClientIQ posclientiq = new POSClientIQ();
posclientiq.connectXMPPServer();
posclientiq.processMessage();
}
public void processMessage()
{ try{
final IQ iq1 = new IQ() {
public String getChildElementXML() {
return "<iq type='get' from ='sam'><query xmlns='jabber:iq:roster'></query></iq>";
}
};
iq1.setType(IQ.Type.GET);
// PacketCollector collector = connection.createPacketCollector(new PacketIDFilter(iq1.getPacketID()));
connection.sendPacket(iq1);
System.out.println("Message send");

The getChildElementXML() returns the tag. If you are using Smack then you don't need to write your own IQ implementation unless it is a custom query. For your case, to query the roster use RosterPacket.

If you have a custom query and you would like to use your IQ implementation then:
final IQ iq = new IQ() {
public String getChildElementXML() {
return "<query xmlns='http://jabber.org/protocol/disco#info'/>"; // here is your query
//this returns "<iq type='get' from='User#YourServer/Resource' id='info1'> <query xmlns='http://jabber.org/protocol/disco#info'/></iq>";
}};
// set the type
iq.setType(IQ.Type.GET);
// send the request
connection.sendPacket(iq);
As you can see you have here your custom query and you use Smack to set the rest of your IQ e.g. setting the type. Please note that Smack fills the "from" for you based on the JID your are logged into.

//To retrieve archive msges from server..
MyCustomIQ iq = new MyCustomIQ();
iq.setType(IQ.Type.set);
mConnection.sendIqWithResponseCallback(iq, new PacketListener() {
#Override
public void processPacket(Packet packet) throws SmackException.NotConnectedException {
Log.i("Send IQ with Response", "****** message " + packet);
}
}, new ExceptionCallback() {
#Override
public void processException(Exception exception) {
exception.printStackTrace();
Log.i("IO archjieve Exception",""+ exception.getMessage());
}
}, 5000);
mConnection.sendPacket(new Presence(Presence.Type.available));
PacketTypeFilter filter=new PacketTypeFilter(org.jivesoftware.smack.packet.Message.class);
PacketListener myListener=new PacketListener(){
public void processPacket(Packet packet){
if(((Message) packet).getType().equals(Message.Type.chat))
{
((Message) packet).getBody();
}
else if(((Message) packet).getType().equals(Message.Type.normal))
{
DefaultPacketExtension pacExten=PacketUtil.packetExtensionfromCollection(packet.getExtensions(), "result", "urn:xmpp:mam:0");
String strMsg=pacExten.getValue("body");
}
}
}
;
mConnection.addPacketListener(myListener, filter);
//My Custom IQ
class MyCustomIQ extends IQ {
String token;
protected MyCustomIQ() {
super("query","urn:xmpp:mam:0");
}
#Override
protected IQChildElementXmlStringBuilder getIQChildElementBuilder(IQChildElementXmlStringBuilder xml) {
// String queryId = prefix + Long.toString(new AtomicLong().incrementAndGet());
xml.attribute("queryid",queryId);
xml.rightAngleBracket();
return xml;
}
}
//You may get the response in PacketListerener sometimes so put debug in that also