I have a cluster of RabbitMQ servers. I want to load balance my StompBrokerRelay requests from my spring boot application (with websockets) to the nodes across the cluster, BUT i don't see where I can set a list of addresses with the MessageBrokerRegistry. Right now the configuration looks like this:
#Override
public void configureMessageBroker(MessageBrokerRegistry config) {
config
.enableStompBrokerRelay("/exchange")
.setAutoStartup(true)
.setVirtualHost(BROKER_VHOST)
.setRelayHost(BROKER_HOST)
.setRelayPort(BROKER_PORT)
.setClientLogin(BROKER_CLIENT_LOGIN)
.setClientPasscode(BROKER_CLIENT_PASSWORD)
.setSystemLogin(BROKER_SYSTEM_LOGIN)
.setSystemPasscode(BROKER_SYSTEM_PASSWORD);
}
Is there some way to .setRelayHosts() or do I need to look for another framework or, heaven forbid, try to finagle this stuff into working with multiple hosts.
It's not possible right now. Spring websocket is sort of half-baked.
Check https://docs.spring.io/spring-framework/docs/current/reference/html/web.html#websocket-stomp-handle-broker-relay-configure. If you wish to supply multiple addresses, on each attempt to connect, you can configure a supplier of addresses, instead of a fixed host and port. Code Snippet also included at the end of the section.
Related
I am using Netty server for a Spring boot application. Is there anyway to monitor the Netty server queue size so that we will come to know if the queue is full and server is not able to accept any new request? Also, Is there any logging by netty server if the queue is full or unable to accept a new request?
Netty does not have any logging for that purpose but I implemented a way to find pending tasks and put some logs according to your question. here is a sample log from my local
you can find all code here https://github.com/ozkanpakdil/spring-examples/tree/master/reactive-netty-check-connection-queue
About code which is very explanatory from itself but NettyConfigure is actually doing the netty configuration in spring boot env. at https://github.com/ozkanpakdil/spring-examples/blob/master/reactive-netty-check-connection-queue/src/main/java/com/mascix/reactivenettycheckconnectionqueue/NettyConfigure.java#L46 you can see "how many pending tasks" in the queue. DiscardServerHandler may help you how to discard if the limit is full. You can use jmeter for the test here is the jmeter file https://github.com/ozkanpakdil/spring-examples/blob/master/reactive-netty-check-connection-queue/PerformanceTestPlanMemoryThread.jmx
if you want to handle netty limit you can do it like the code below
#Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
totalConnectionCount.incrementAndGet();
if (ctx.channel().isWritable() == false) { // means we hit the max limit of netty
System.out.println("I suggest we should restart or put a new server to our pool :)");
}
super.channelActive(ctx);
}
You should check https://stackoverflow.com/a/49823055/175554 for handling the limits and here is another explanation about "isWritable" https://stackoverflow.com/a/44564482/175554
One more extra, I put actuators in the place http://localhost:8080/actuator/metrics/http.server.requests is nice to check too.
I have a Spring Boot app (Jhipster) that uses STOMP over WebSockets to communicate information from the server to users.
I recently added an ActiveMQ server to handle scaling the app horizontally, with an Amazon auto-scaling group / load-balancer.
I make use the convertAndSendToUser() method, which works on single instances of the app to locate the authenticated users' "individual queue" so only they receive the message.
However, when I launch the app behind the load balancer, I am finding that messages are only being sent to the user if the event is generated on the server that their websocket-proxy connection (to the broker) is established on?
How do I ensure the message goes through ActiveMQ to whichever instance of the app that the user is actually "connected too" regardless of which instance receives, say an HTTP Request that executes the convertAndSendToUser() event?
For reference here is my StompBrokerRelayMessageHandler:
#Bean
public AbstractBrokerMessageHandler stompBrokerRelayMessageHandler() {
StompBrokerRelayMessageHandler handler = (StompBrokerRelayMessageHandler) super.stompBrokerRelayMessageHandler();
handler.setTcpClient(new Reactor2TcpClient<>(
new StompTcpFactory(orgProperties.getAws().getAmazonMq().getStompRelayHost(),
orgProperties.getAws().getAmazonMq().getStompRelayPort(), orgProperties.getAws().getAmazonMq
().getSsl())
));
return handler;
}
#Override
public void configureMessageBroker(MessageBrokerRegistry config) {
config.enableStompBrokerRelay("/queue", "/topic")
.setSystemLogin(orgProperties.getAws().getAmazonMq().getStompRelayHostUser())
.setSystemPasscode(orgProperties.getAws().getAmazonMq().getStompRelayHostPass())
.setClientLogin(orgProperties.getAws().getAmazonMq().getStompRelayHostUser())
.setClientPasscode(orgProperties.getAws().getAmazonMq().getStompRelayHostPass());
config.setApplicationDestinationPrefixes("/app");
}
I have found the name corresponding to the queue that is generated on ActiveMQ by examining the headers in the SessionSubscribeEvent, that is generated in the listener when a user subscribes to a user-queue, as simpSessionId.
#Override
#EventListener({SessionSubscribeEvent.class})
public void onSessionSubscribeEvent(SessionSubscribeEvent event) {
log.debug("Session Subscribe Event:" +
"{}", event.getMessage().getHeaders().toString());
}
Corresponding queues' can be found in ActiveMQ, in the format: {simpDestination}-user{simpSessionId}
Could I save the sessionId in a key-value pair and just push messages onto that topic channel?
I also found some possibilities of setting ActiveMQ specific STOMP properties in the CONNECT/SUBSCRIBE frame to create durable subscribers if I set these properties will Spring than understand the routing?
client-id & subcriptionName
Modifying the MessageBrokerReigstry config resolved the issue:
config.enableStompBrokerRelay("/queue", "/topic")
.setUserDestinationBroadcast("/topic/registry.broadcast")
Based on this paragraph in the documentation section 4.4.13:
In a multi-application server scenario a user destination may remain
unresolved because the user is connected to a different server. In
such cases you can configure a destination to broadcast unresolved
messages to so that other servers have a chance to try. This can be
done through the userDestinationBroadcast property of the
MessageBrokerRegistry in Java config and the
user-destination-broadcast attribute of the message-broker element in
XML
I did not see any documentation on "why" /topic/registry.broadcast was the correct "topic" destination, but I am finding various iterations of it:
websocket sessions sample doesn't cluster.. spring-session-1.2.2
What is MultiServerUserRegistry in spring websocket?
Spring websocket - sendToUser from a cluster does not work from backup server
We use spring kafka configuration to receive messages from upstream systems.
We have java configuration for topic configuration
#Bean(id="firstcontainer")
protected ConcurrentMessageListenerContainer createContainerInstance(...) {
//topics addition
}
#Bean(id="secondcontainer")
protected ConcurrentMessageListenerContainer createContainerInstance(...) {
//topics addition
}
#KafkaListener(firstcontainer)
public void listenerFirst(){
}
#KafkaListener(secondcontainer)
public void listenerSecond(){
}
This code works perfectly fine as we have seperate containerfactory.
Now we have requirement to spin up mulitple instances of this application where one instance will listen to firstContainer and secondContainer will be disabled
And For second instance, it will only enable secondContainer and disable firstContainer.
Can someone help to understand if it is possible to disable listening from a topic(list of topics)?
Your two instances (or many) can be identical and accept topic list from the external configuration. The #KafkaListener allows to do that.
There is Spring #Profile functionality, if you still want to keep several beans in your application. This way you should sever your #KafkaListener method to different classes and mark their component with an appropriate #Profile, which, again, can be activated externally.
The Apache Kafka has a concept as Consumer Group meaning that all consumers in the same group are joining to the broker, but only one of them will consume records from single partition in the topic. This way independently of the number of instances of your application you still will have a consistency because there is nothing to worry about duplicates in case of proper Kafka groups usage.
I have a (legacy) TCP service that has multiple processes. Each process runs on the same host, but on a different port. The service is single threaded, so the way to increase throughput is to round-robin each request across each of the ports.
I am providing an AMQP exposure to this legacy application. Its very simple - take a string off the AMQP queue, pass it to the application, and return the response string to the AMQP reply queue.
This works great on a single port. However, i'd like to fan out the requests across all the ports.
Spring Integration seems to only provide AbstractClientConnectionFactory implementations that either connect directly to a single host/port (TcpNetClientConnectionFactory) or maintain a pool of connections to a single host/port (CachingClientConnectionFactory). There arent any that pool connections between a single host and multiple ports.
I have attempted to write my own AbstractClientConnectionFactory that maintains a pool of AbstractClientConnectionFactory objects and round-robins between them. However, I have struck several issues to do with handing the TCP connections when the target service goes away or the network is interrupted that I have not been able to solve.
There is also the approach taken by this question: Spring Integration 4 - configuring a LoadBalancingStrategy in Java DSL but the solution to that was to hardcode the number of endpoints. In my case, the number of endpoints is only known at runtime and is a user-configurable setting.
So, basically I need to create a TcpOutboundGateway per port dynamically at runtime and somehow register it in my IntegrationFlow. I have attempted the following:
#Bean
public IntegrationFlow xmlQueryWorkerIntegrationFlow() {
SimpleMessageListenerContainer inboundQueue = getMessageListenerContainer();
DirectChannel rabbitReplyChannel = MessageChannels.direct().get();
IntegrationFlowBuilder builder = IntegrationFlows
.from(Amqp.inboundGateway(inboundQueue)
.replyChannel(rabbitReplyChannel))
/* SOMEHOW DO THE ROUND ROBIN HERE */
//I have tried:
.channel(handlerChannel()) //doesnt work, the gateways dont get started and the message doesnt get sent to the gateway
//and I have also tried:
.handle(gateway1)
.handle(gateway2) //doesnt work, it chains the handlers instead of round-robining between them
//
.transform(new ObjectToStringTransformer())
.channel(rabbitReplyChannel);
return builder.get();
}
#Bean
//my attempt at dynamically adding handlers to the same channel and load balancing between them
public DirectChannel handlerChannel() {
DirectChannel channel = MessageChannels.direct().loadBalancer(new RoundRobinLoadBalancingStrategy()).get();
for (AbstractClientConnectionFactory factory : generateConnections()) {
channel.subscribe(generateTcpOutboundGateway(factory));
}
return channel;
}
Does anyone know how I can solve this problem?
See the dynamic ftp sample - in essence each outbound gateway goes in its own application context and the dynamic router routes to the appropriate channel (for which the outbound adapter is created on demand if necessary).
Although the sample uses XML, you can do the same thing with java configuration, or even with the Java DSL.
See my answer to a similar question for multiple IMAP mail adapters using Java configuration and then a follow-up question.
Is it possible to set a dynamic provider for a Marshalling web service outbound gateway?
I mean, if I try for example: http://100.0.0.1 and it not works, I would like to try http://100.0.0.2 instead
My current configuration:
MarshallingWebServiceOutboundGateway gw = new MarshallingWebServiceOutboundGateway(provider, jaxb2Marshaller(), jaxb2Marshaller());
Yes, that's true. Since MarshallingWebServiceOutboundGateway allows to inject DestinationProvider, you feel free to provide any custom implementation.
For your fault-tolerant use-case you should do: new URLConnection(url).connect() to test connection to the target server in that your DestinationProvider implementation.
UPDATE
But If I how can I test new URLConnection(url).connect() if I have https credentials, certificate or any kind of security
Well, another good solution from the Spring Integration is load-balancing and several subscribers to the same DirectChannel:
#Bean
public MessageChannel wsChannel() {
return new DirectChannel(null);
}
to switch of the default RoundRobinLoadBalancingStrategy.
And after that you can have several #ServiceActivator(inputChannel="wsChannel"). When the first one is fail, the message is sent to the second and so on, until the good result or the fall for each URL.