This is also not a duplicate of 'Connection aborted' error while trying to send events to Azure Event Hub using java EventHubClient API because the issue in this question was related to proxy. This is NOT an issue with my proxy settings as this code works for Singe Event hub client
My Question: Is it possible to have a Java Application which sends messages to TWO or more Event Hub Clients?
I am trying to publish/send event data to Multiple instances of Azure Event hubs.
I have provisioned TWO event hub namespaces and each namespace has its event hub.
I have in all TWO event hubs which have their own Connection Strings, SAS Keys and Namespaces and Names.
Since each event hub namespace can only support 20 Throughput units without manual intervention( service request), I am trying to find if I can send my data to Multiple Event hubs.
I can see that my code works fine for SINGLE EventHubClient. The moment, my code tries to create the second EventHubClient, I get this connection aborted exception.
I am using the sample code shared on azure's git hub at https://github.com/MicrosoftDocs/azure-docs/blob/master/articles/event-hubs/event-hubs-java-get-started-send.md
I see the below exception:
Exception in thread "main" com.microsoft.azure.eventhubs.EventHubException: connection aborted
at com.microsoft.azure.eventhubs.impl.ExceptionUtil.toException(ExceptionUtil.java:59)
at com.microsoft.azure.eventhubs.impl.MessagingFactory.onConnectionError(MessagingFactory.java:249)
at com.microsoft.azure.eventhubs.impl.ConnectionHandler.onTransportError(ConnectionHandler.java:102)
at org.apache.qpid.proton.engine.BaseHandler.handle(BaseHandler.java:191)
at org.apache.qpid.proton.engine.impl.EventImpl.dispatch(EventImpl.java:108)
at org.apache.qpid.proton.reactor.impl.ReactorImpl.dispatch(ReactorImpl.java:324)
at org.apache.qpid.proton.reactor.impl.ReactorImpl.process(ReactorImpl.java:291)
at com.microsoft.azure.eventhubs.impl.MessagingFactory$RunReactor.run(MessagingFactory.java:445)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Any pointers/inputs will be highly appreciated.
Here is the relevant code:
public class Sender {
private static final String EVENTHUB_NS1= "TT";
private static final String EVENTHUB1= "TT";
private static final String SAS_KEY_NAME1= "RootManageSharedAccessKey";
private static final String SAS_KEY_VAL1= "SECRET1";
private static final String EVENTHUB_NS2= "TT1";
private static final String EVENTHUB2= "TT1";
private static final String SAS_KEY_NAME2= "RootManageSharedAccessKey";
private static final String SAS_KEY_VAL2= "SECRET2";
private EventData getEventData(int eventDataPrefix) throws IOException, URISyntaxException {
String msgData = "<=>"+eventDataPrefix + "<=>"+"TEST MESSAGE..";
final Gson gson = new GsonBuilder().create();
byte [] data =gson.toJson(msgData).getBytes(Charset.defaultCharset());
EventData ed = EventData.create(data);
return ed;
}
public static final int MAX_BATCH_SIZE=100;
private List<EventData> getBatchOfEvents() throws IOException, URISyntaxException {
List<EventData> events = new ArrayList<>();
for(int i = 0; i < MAX_BATCH_SIZE; i ++){
events.add(getEventData(i));
}
return events;
}
private List<String> getConnectionStrings(){
List<String> connStrings = new ArrayList<>();
ConnectionStringBuilder csBldr1 = new ConnectionStringBuilder();
csBldr1.setNamespaceName(EVENTHUB_NS1);
csBldr1.setEventHubName(EVENTHUB1);
csBldr1.setSasKeyName(SAS_KEY_NAME1);
csBldr1.setSasKey(SAS_KEY_VAL1);
ConnectionStringBuilder csbldr2 = new ConnectionStringBuilder();
csbldr2.setNamespaceName(EVENTHUB_NS2);
csbldr2.setEventHubName(EVENTHUB2);
csbldr2.setSasKeyName(SAS_KEY_NAME2);
csbldr2.setSasKey(SAS_KEY_VAL2);
connStrings.add(csBldr1.toString());
connStrings.add(csbldr2.toString());
return connStrings;
}
private List<EventHubClient> getEHClients() throws IOException, EventHubException, ExecutionException, InterruptedException {
List<EventHubClient> ehClients = new ArrayList<>();
System.out.println("Starting getEhCLients..");
for( String connStr: getConnectionStrings()){
final ExecutorService executorService = Executors.newSingleThreadExecutor();
//The second iteration of for loop gives the EventHubException
EventHubClient client= EventHubClient.createSync(connStr, executorService);
ehClients.add(client);
System.out.println("EH CONNSTR::"+connStr);
}
return ehClients;
}
private void sendBatch( List<EventData> events) throws IOException, EventHubException, ExecutionException, InterruptedException {
List<EventHubClient> ehClients = getEHClients();
if( ehClients.size() <=0) {
System.out.println("NO EH CLients.. to send..");
return;
}
for(int i = 0; i < events.size();i++){
EventData data = events.get(i);
int ehClientIndex = i % ehClients.size();
EventHubClient client = ehClients.get(ehClientIndex);
client.sendSync(data);
System.out.print("MsgSent:"+ehClientIndex);
}
System.out.println("\nDone");
}
public static void main(String[] args) throws IOException, URISyntaxException, EventHubException, ExecutionException, InterruptedException {
Sender sender = new Sender();
List<EventData> events = sender.getBatchOfEvents();
sender.sendBatch(events);
}
}
Very interesting use case, I could try to reproduce from my side. My guess is that EventHubClient has some static field, which will be shared by multiple instance, this might cause your issue.
Besides that, I want to understand why use two namespace, how to about one namespace with higher throughput. One namespace is like a cluster. Actually, I'm from Spring Cloud Azure, and try to improve Java experience on Azure. Feel free to try our event hub binder. https://github.com/Microsoft/spring-cloud-azure
Related
I am trying to send my tests to testrail from selenium but im not using an assert to end the test, i just want it to pass if it runs to completion? Is this possible? Also is there any examples of how this working in the code? I currently have:
public class login_errors extends ConditionsWebDriverFactory {
public static String TEST_RUN_ID = "R1713";
public static String TESTRAIL_USERNAME = "f2009#hotmail.com";
public static String TESTRAIL_PASSWORD = "Password100";
public static String RAILS_ENGINE_URL = "https://testdec.testrail.com/";
public static final int TEST_CASE_PASSED_STATUS = 1;
public static final int TEST_CASE_FAILED_STATUS = 5;
#Test
public void login_errors() throws IOException, APIException {
Header header = new Header();
header.guest_select_login();
Pages.Login login = new Pages.Login();
login.login_with_empty_fields();
login.login_with_invalid_email();
login.email_or_password_incorrect();
login.login_open_and_close();
login_errors.addResultForTestCase("T65013",TEST_CASE_PASSED_STATUS," ");
}
public static void addResultForTestCase(String testCaseId, int status,
String error) throws IOException, APIException {
String testRunId = TEST_RUN_ID;
APIClient client = new APIClient(RAILS_ENGINE_URL);
client.setUser(TESTRAIL_USERNAME);
client.setPassword(TESTRAIL_PASSWORD);
Map data = new HashMap();
data.put("status_id", status);
data.put("comment", "Test Executed - Status updated automatically from Selenium test automation.");
client.sendPost("add_result_for_case/"+testRunId+"/"+testCaseId+"",data );
}
}
I am getting a 401 status from this code.
Simply place the addResultForTestCase method at the end of the run. Ensure the Test CASE is used rather than the run id. You are currently using the incorrect ID
I am having trouble sending my test results from selenium to testrail. I cant seem to figure it out using the paperwork provided. I am currently using this:
public class login_errors extends ConditionsWebDriverFactory {
public static String TEST_RUN_ID = "R1713";
public static String TESTRAIL_USERNAME = "testemai9#hotmail.com";
public static String TESTRAIL_PASSWORD = "Password1";
public static String RAILS_ENGINE_URL = "https://testproj.testrail.com/";
public static final int TEST_CASE_PASSED_STATUS = 1;
public static final int TEST_CASE_FAILED_STATUS = 5;
#Test
public void login_errors() throws IOException, APIException {
Header header = new Header();
header.guest_select_login();
Pages.Login login = new Pages.Login();
login.login_with_empty_fields();
login.login_with_invalid_email();
login.email_or_password_incorrect();
login.login_open_and_close();
login_errors.addResultForTestCase(TEST_RUN_ID,TEST_CASE_PASSED_STATUS," ");
}
public static void addResultForTestCase(String testCaseId, int status,
String error) throws IOException, APIException {
String testRunId = TEST_RUN_ID;
APIClient client = new APIClient(RAILS_ENGINE_URL);
client.setUser(TESTRAIL_USERNAME);
client.setPassword(TESTRAIL_PASSWORD);
Map data = new HashMap();
data.put("status_id", status);
data.put("comment", "Test Executed - Status updated automatically from Selenium test automation.");
client.sendPost("add_result_for_case/"+testRunId+"/"+testCaseId+"",data );
}
}
But i keep getting the following exception:
com.gurock.testrail.APIException: TestRail API returned HTTP
401("Authentication failed: invalid or missing user/password or
session cookie.")
Can anybody help me on the exact way this should be done out in java? I am not sure I am doing it correctly.
I'm using my own custom made API for testrail, but it is all based on same thing.
But looking to official gurrock,
documentation
First You need to add "testrail/" at the end of Your URL endpoint,
APIClient client = new APIClient("http://<server>/testrail/");
client.setUser("..");
client.setPassword("..");
Should be like this:
public static String RAILS_ENGINE_URL ="https://testproj.testrail.com/testrail/";
Second thing what I found out is that You're sending test run id in variable for testcase ID, this is not same.
And another thing is that test case ID shouldn't be with anything in front just pure number, not like "R123" but "123"
And Your method should than accept one more parameter, testRunId
public static void addResultForTestCase(String testRunId, String testCaseId, int status,String error) throws IOException, APIException {
String testRunId = TEST_RUN_ID;
APIClient client = new APIClient(RAILS_ENGINE_URL);
client.setUser(TESTRAIL_USERNAME);
client.setPassword(TESTRAIL_PASSWORD);
Map data = new HashMap();
data.put("status_id", status);
data.put("comment", "Test Executed - Status updated automatically from Selenium test automation.");
client.sendPost("add_result_for_case/"+testRunId+"/"+testCaseId+"",data );
}
And another thing is that You have to have created testrun, so You can have Yourself your testrun ID, like pic bellow:
And than test case ID is different from testrun id.
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.
Uses on-line decomentation I come up with the following code to terminate the current EC2 Instance:
public class Ec2Utility {
static private final String LOCAL_META_DATA_ENDPOINT = "http://169.254.169.254/latest/meta-data/";
static private final String LOCAL_INSTANCE_ID_SERVICE = "instance-id";
static public void terminateMe() throws Exception {
TerminateInstancesRequest terminateRequest = new TerminateInstancesRequest().withInstanceIds(getInstanceId());
AmazonEC2 ec2 = new AmazonEC2Client();
ec2.terminateInstances(terminateRequest);
}
static public String getInstanceId() throws Exception {
//SimpleRestClient, is an internal wrapper on http client.
SimpleRestClient client = new SimpleRestClient(LOCAL_META_DATA_ENDPOINT);
HttpResponse response = client.makeRequest(METHOD.GET, LOCAL_INSTANCE_ID_SERVICE);
return IOUtils.toString(response.getEntity().getContent(), "UTF-8");
}
}
My issue is that my EC2 instance is under an AutoScalingGroup which is under a CloudFormationStack, that is because of my organisation deployment standards though this single EC2 is all there is there for this feature.
So, I want to terminate the entire CloudFormationStack from the JavaSDK, keep in mind, I don't have the CloudFormation Stack Name in advance as I didn't have the EC2 Instance Id so I will have to get it from the code using the API calls.
How can I do that, if I can do it?
you should be able to use the deleteStack method from cloud formation sdk
DeleteStackRequest request = new DeleteStackRequest();
request.setStackName(<stack_name_to_be_deleted>);
AmazonCloudFormationClient client = new AmazonCloudFormationClient (<credentials>);
client.deleteStack(request);
If you don't have the stack name, you should be able to retrieve from the Tag of your instance
DescribeInstancesRequest request =new DescribeInstancesRequest();
request.setInstanceIds(instancesList);
DescribeInstancesResult disresult = ec2.describeInstances(request);
List <Reservation> list = disresult.getReservations();
for (Reservation res:list){
List <Instance> instancelist = res.getInstances();
for (Instance instance:instancelist){
List <Tag> tags = instance.getTags();
for (Tag tag:tags){
if (tag.getKey().equals("aws:cloudformation:stack-name")) {
tag.getValue(); // name of the stack
}
}
At the end I've achieved the desired behaviour using the set of the following util functions I wrote:
/**
* Delete the CloudFormationStack with the given name.
*
* #param stackName
* #throws Exception
*/
static public void deleteCloudFormationStack(String stackName) throws Exception {
AmazonCloudFormationClient client = new AmazonCloudFormationClient();
DeleteStackRequest deleteStackRequest = new DeleteStackRequest().withStackName("");
client.deleteStack(deleteStackRequest);
}
static public String getCloudFormationStackName() throws Exception {
AmazonEC2 ec2 = new AmazonEC2Client();
String instanceId = getInstanceId();
List<Tag> tags = getEc2Tags(ec2, instanceId);
for (Tag t : tags) {
if (t.getKey().equalsIgnoreCase(TAG_KEY_STACK_NAME)) {
return t.getValue();
}
}
throw new Exception("Couldn't find stack name for instanceId:" + instanceId);
}
static private List<Tag> getEc2Tags(AmazonEC2 ec2, String instanceId) throws Exception {
DescribeInstancesRequest describeInstancesRequest = new DescribeInstancesRequest().withInstanceIds(instanceId);
DescribeInstancesResult describeInstances = ec2.describeInstances(describeInstancesRequest);
List<Reservation> reservations = describeInstances.getReservations();
if (reservations.isEmpty()) {
throw new Exception("DescribeInstances didn't returned reservation for instanceId:" + instanceId);
}
List<Instance> instances = reservations.get(0).getInstances();
if (instances.isEmpty()) {
throw new Exception("DescribeInstances didn't returned instance for instanceId:" + instanceId);
}
return instances.get(0).getTags();
}
// XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
// Example of usage from the code:
deleteCloudFormationStack(getCloudFormationStackName());
// XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
Play 2.5 Highlights states
Better control over WebSocket frames
The Play 2.5 WebSocket API gives you direct control over WebSocket frames. You can now send and receive binary, text, ping, pong and close frames. If you don’t want to worry about this level of detail, Play will still automatically convert your JSON or XML data into the right kind of frame.
However
https://www.playframework.com/documentation/2.5.x/JavaWebSockets has examples around LegacyWebSocket which is deprecated
What is the recommended API/pattern for Java WebSockets? Is using
LegacyWebSocket the only option for java websockets?
Are there any examples using new Message types ping/pong to implement a heartbeat?
The official documentation on this is disappointingly very sparse. Perhaps in Play 2.6 we'll see an update to this. However, I will provide an example below on how to configure a chat websocket in Play 2.5, just to help out those in need.
Setup
AController.java
#Inject
private Materializer materializer;
private ActorRef chatSocketRouter;
#Inject
public AController(#Named("chatSocketRouter") ActorRef chatInjectedActor) {
this.chatSocketRouter = chatInjectedActor;
}
// Make a chat websocket for a user
public WebSocket chatSocket() {
return WebSocket.Json.acceptOrResult(request -> {
String authToken = getAuthToken();
// Checking of token
if (authToken == null) {
return forbiddenResult("No [authToken] supplied.");
}
// Could we find the token in the database?
final AuthToken token = AuthToken.findByToken(authToken);
if (token == null) {
return forbiddenResult("Could not find [authToken] in DB. Login again.");
}
User user = token.getUser();
if (user == null) {
return forbiddenResult("You are not logged in to view this stream.");
}
Long userId = user.getId();
// Create a function to be run when we initialise a flow.
// A flow basically links actors together.
AbstractFunction1<ActorRef, Props> getWebSocketActor = new AbstractFunction1<ActorRef, Props>() {
#Override
public Props apply(ActorRef connectionProperties) {
// We use the ActorRef provided in the param above to make some properties.
// An ActorRef is a fancy word for thread reference.
// The WebSocketActor manages the web socket connection for one user.
// WebSocketActor.props() means "make one thread (from the WebSocketActor) and return the properties on how to reference it".
// The resulting Props basically state how to construct that thread.
Props properties = ChatSocketActor.props(connectionProperties, chatSocketRouter, userId);
// We can have many connections per user. So we need many ActorRefs (threads) per user. As you can see from the code below, we do exactly that. We have an object called
// chatSocketRouter which holds a Map of userIds -> connectionsThreads and we "tell"
// it a lightweight object (UserMessage) that is made up of this connecting user's ID and the connection.
// As stated above, Props are basically a way of describing an Actor, or dumbed-down, a thread.
// In this line, we are using the Props above to
// reference the ActorRef we've just created above
ActorRef anotherUserDevice = actorSystem.actorOf(properties);
// Create a lightweight object...
UserMessage routeThisUser = new UserMessage(userId, anotherUserDevice);
// ... to tell the thread that has our Map that we have a new connection
// from a user.
chatSocketRouter.tell(routeThisUser, ActorRef.noSender());
// We return the properties to the thread that will be managing this user's connection
return properties;
}
};
final Flow<JsonNode, JsonNode, ?> jsonNodeFlow =
ActorFlow.<JsonNode, JsonNode>actorRef(getWebSocketActor,
100,
OverflowStrategy.dropTail(),
actorSystem,
materializer).asJava();
final F.Either<Result, Flow<JsonNode, JsonNode, ?>> right = F.Either.Right(jsonNodeFlow);
return CompletableFuture.completedFuture(right);
});
}
// Return this whenever we want to reject a
// user from connecting to a websocket
private CompletionStage<F.Either<Result, Flow<JsonNode, JsonNode, ?>>> forbiddenResult(String msg) {
final Result forbidden = Results.forbidden(msg);
final F.Either<Result, Flow<JsonNode, JsonNode, ?>> left = F.Either.Left(forbidden);
return CompletableFuture.completedFuture(left);
}
ChatSocketActor.java
public class ChatSocketActor extends UntypedActor {
private final ActorRef out;
private final Long userId;
private ActorRef chatSocketRouter;
public ChatSocketActor(ActorRef out, ActorRef chatSocketRouter, Long userId) {
this.out = out;
this.userId = userId;
this.chatSocketRouter = chatSocketRouter;
}
public static Props props(ActorRef out, ActorRef chatSocketRouter, Long userId) {
return Props.create(ChatSocketActor.class, out, chatSocketRouter, userId);
}
// Add methods here handling each chat connection...
}
ChatSocketRouter.java
public class ChatSocketRouter extends UntypedActor {
public ChatSocketRouter() {}
// Stores userIds to websockets
private final HashMap<Long, List<ActorRef>> senders = new HashMap<>();
private void addSender(Long userId, ActorRef actorRef){
if (senders.containsKey(userId)) {
final List<ActorRef> actors = senders.get(userId);
actors.add(actorRef);
senders.replace(userId, actors);
} else {
List<ActorRef> l = new ArrayList<>();
l.add(actorRef);
senders.put(userId, l);
}
}
private void removeSender(ActorRef actorRef){
for (List<ActorRef> refs : senders.values()) {
refs.remove(actorRef);
}
}
#Override
public void onReceive(Object message) throws Exception {
ActorRef sender = getSender();
// Handle messages sent to this 'router' here
if (message instanceof UserMessage) {
UserMessage userMessage = (UserMessage) message;
addSender(userMessage.userId, userMessage.actorRef);
// Watch sender so we can detect when they die.
getContext().watch(sender);
} else if (message instanceof Terminated) {
// One of our watched senders has died.
removeSender(sender);
} else {
unhandled(message);
}
}
}
Example
Now whenever you want to send a client with a websocket connection a message you can do something like:
ChatSenderController.java
private ActorRef chatSocketRouter;
#Inject
public ChatSenderController(#Named("chatSocketRouter") ActorRef chatInjectedActor) {
this.chatSocketRouter = chatInjectedActor;
}
public static void sendMessage(Long sendToId) {
// E.g. send the chat router a message that says hi
chatSocketRouter.tell(new Message(sendToId, "Hi"));
}
ChatSocketRouter.java
#Override
public void onReceive(Object message) throws Exception {
// ...
if (message instanceof Message) {
Message messageToSend = (Message) message;
// Loop through the list above and send the message to
// each connection. For example...
for (ActorRef wsConnection : senders.get(messageToSend.getSendToId())) {
// Send "Hi" to each of the other client's
// connected sessions
wsConnection.tell(messageToSend.getMessage());
}
}
// ...
}
Again, I wrote the above to help out those in need. After scouring the web I could not find a reasonable and simple example. There is an open issue for this exact topic. There are also some examples online but none of them were easy to follow. Akka has some great documentation but mixing it in with Play was a tough mental task.
Please help improve this answer if you see anything that is amiss.