I have an apache-camel JMS route.
form("jms:queue:sourceQueue").to("messageProcessor")
My requirement is to stop route on 3 message processing failures. In messageProcessor class, in catch block I am checking for error count and as soon as it reaches 3, I am inovking
camelContext.stopRoute(routeID, 3, TimeUnit.SECONDS);
My route do not stop and spring's DefaultMessageListenerContainer writes following line in log
Shutting down JMS listener container
Waiting for shutdown of message listener invokers
Still waiting for shutdown of 1 message listener invokers
I am trying to figure out, what is holding DMLC from stopping?
What camel attribute I am missing?
If I use asyncStopListener=true then camle route stops but a thread keeps waiting in background to stop listener.
Are you stopping a route from a route? eg if you do that in the
processor, then see this FAQ
http://camel.apache.org/how-can-i-stop-a-route-from-a-route.html
Related
I am reading a file from a directory, and trying to call an API based on the data in the file.
While trying to handle the exceptions, I am facing an issue. I am trying to configure the onException block to redeliver 3 times, with a delay of 5 seconds. The issue occurs, when I am setting handled(true). This configuration does not redeliver, and stops as soon as the exception occurs.
This is my onException block:
onException(HttpOperationFailedException.class)
.log(LoggingLevel.ERROR, logger, "Error occurred while connecting to API for file ${header.CamelFileName} :: ${exception.message}")
.log("redelivery counter :: ${header.CamelRedeliveryCounter}")
.maximumRedeliveries(3)
.redeliveryDelay(5000)
.handled(true);
How do I do both, i.e. handle as well as redeliver?
Unless you use a buggy version of Camel, the redeliveries are made as expected whatever if it is handled or not.
The only difference between handled or not, is the fact that the result sent back to the client once the retries are exhausted will be either the exception (not handled) or the result of your onException (handled).
Your mistake here, is the fact that you assume that the log EIPs that you have defined in your onException are called for each retry while they are actually called only when the retries are exhausted.
If you want to see the retries in your logs, you can use retryAttemptedLogLevel as next:
onException(HttpOperationFailedException.class)
.maximumRedeliveries(3)
.redeliveryDelay(5000)
.retryAttemptedLogLevel(LoggingLevel.WARN);
You will then get warning messages of type:
Failed delivery for (MessageId: X on ExchangeId: Y). On delivery attempt: Z caught: ...
I have set up the Apache camel in which i consumes the message from one queue and do some kind of operation on it and then transfers it to other queue .
Now if the exception comes then i want that it should rollback and then after 6 attempts it to send to dead letter queue , Currently rollback happens 5-6 times but my message is not transferred to dead letter queue .
Here What happens -->
Queue1-->(Consumes)-->Operation(Exception thrown)--> rollback --> again Queue1-->(Consumes) --> Operation(Exception thrown)-->rollback -->... this happens 5-6 times and then my message is lost
I dont know where my message is going and why it is getting lost , and from my Active MQ GUI i can see it is dequeued.
#Bean
public RedeliveryPolicy redeliveryPolicy() {
RedeliveryPolicy redeliveryPolicy = new RedeliveryPolicy();
redeliveryPolicy.setMaximumRedeliveries(2);
redeliveryPolicy.setMaximumRedeliveryDelay(10000);
redeliveryPolicy.setRedeliveryDelay(10000);
return redeliveryPolicy;
}
---------------------Route extends SpringRouteBuilder-------------------
onException(MyException.class)
.markRollbackOnly()
.redeliveryPolicy(redeliveryPolicy)
.useExponentialBackOff()
.handled(true)
from("jms:queue:Queue1")
.process(new Processor(){
public void process(Exchange ex){
throw new RuntimeException();
}
}).to("jms:queue:myQueue)
I assume there are multiple problems.
markRollbackOnly stops the message. After this statement no further routing is done.
That is the reason why your RedeliveryPolicy and the rest of your onException route is completely ignored. You configure 2 redelivery attempts but you write it does 5 (the default redelivery of ActiveMQ).
To fix this, move markRollbackOnly to the end of your onException route
If you consume transacted from your JMS broker the message must not get lost.
Since you lose it in case of an error, there is a problem with your transaction config. Configure the ActiveMQ component of Camel to use local JMS transactions when consuming.
#Bean(name = "activemq")
#ConditionalOnClass(ActiveMQComponent.class)
public ActiveMQComponent activeMQComponent(ConnectionFactory connectionFactory) {
ActiveMQComponent activeMQComponent = new ActiveMQComponent();
activeMQComponent.setConnectionFactory(connectionFactory);
activeMQComponent.setTransacted(true);
activeMQComponent.setLazyCreateTransactionManager(false);
return activeMQComponent;
}
When this is in place, you can in fact remove the onException route because the redelivery is done by the JMS broker, so you have to configure the redelivery settings on your JMS connection. If the configured redelivery is exhausted and the message still produces a rollback, it is moved to the DLQ.
Be aware when using an additional onException route because this is pure Camel. The Camel error handler does NOT redeliver on route level, but on processor level. So if you configure both broker and Camel redelivery, it can multiply them.
I have a Camel rest endpoint (Jetty) which validates and processes incoming requests. Besides specific Exception handlers (onException) it uses a DLQ error handler (errorHandler(deadLetterChannel...)) which is setup to retry 3 times - if unsuccessful the message is moved to the DLQ.
My question is, how do I still return a user friendly error message back to the client if an unexpected Exception occurs rather than the full Exception body? Is there some config I'm missing on the errorHandler?
I've tried to find some examples on the camel unit tests (DeadLetterChannelHandledExampleTest) and camel in action 2 (Chapter 11) but none seemed to have specific examples for this scenario.
Code is:
.from(ROUTE_URI)
.errorHandler(deadLetterChannel("{{activemq.webhook.dlq.queue}}")
.onPrepareFailure(new FailureProcessor())
.maximumRedeliveries(3)
.redeliveryDelay(1000))
.bean(ParcelProcessor.class, "process");
Thank you for your help!
Use a 2nd route as the DLQ, eg direct:dead and then send the message first to the real DLQ, and then do the message transformation afterwards to return a friendly response.
errorHandler(deadLetterChannel("direct:dead")
from("direct:dead")
.to("{{activemq.webhook.dlq.queue}}")
.transform(constant("Sorry something was wrong"));
I'm using Camel within a Spring boot application and integrate with RabbitMQ but am encountering strange behaviour.
My app has Restful endpointswhich convert the http request to a RabbitMQ message and publish this to a predefined exchange. There is a separate consumer app which listens to a queue and processes the messages.
I have deliberately entered an incorrect rabbitmq exchange name (invalidxchangename)to check that the application will fail if the exchange does not exist however the camel context starts without error and when I send in a first request is does not report any error. This message gets lost as there is no matching RabbitMQ exchange. When I submit a second request I receive the following exception which I would have expected on route startup.
com.rabbitmq.client.AlreadyClosedException: channel is already closed due to channel error; protocol method: #method<channel.close>(reply-code=404, reply-text=NOT_FOUND - no exchange 'invalidxchangename' in vhost
EDIT:
I've tried a more simple example to show the issue in Camel.
I've created a simple route as follows:
from("file:in?fileName=in.txt").log(LoggingLevel.DEBUG, "in here!").to("rabbitmq://localhost:5762/invalidexchange?declare=false");
where there is an existing RabbitMQ exchange called validexchange (so I have deliberately made a typo in the RabbitMQ uri). I would expect the camel route to fail at startup since the exchange doesn't exist, or even the first time it tries to process a new in.txt file.
What I am actually seeing in the logs is that on start up it reports no error and only on the 2nd invocation of the route does it report an error.
2015-03-11 16:17:04.356 INFO 9756 : ID-SBMELW7W-06220-59960-1426051020468-0-2 >>> (route2) from(file://in?fileName=in.txt) --> log[in here!] <<< Pattern:InOnly, Headers:...
2015-03-11 16:17:04.360 INFO 9756 : ID-SBMELW7W-06220-59960-1426051020468-0-2 >>> (route2) log[in here!] --> rabbitmq://localhost:5762/customerchannel.exchang?declare=false <<< Pattern:InOnly, Headers:...
2015-03-11 16:17:45.073 INFO 9756 : ID-SBMELW7W-06220-59960-1426051020468-0-4 >>> (route2) from(file://in?fileName=in.txt) --> log[in here!] <<< Pattern:InOnly, Headers: ...
2015-03-11 16:17:45.079 INFO 9756 : ID-SBMELW7W-06220-59960-1426051020468-0-4 >>> (route2) log[in here!] --> rabbitmq://localhost:5762/customerchannel.exchang?declare=false <<< Pattern:InOnly, Headers:...
2015-03-11 16:17:45.092 ERROR 9756 : Failed delivery for (MessageId: ID-SBMELW7W-06220-59960-1426051020468-0-3 on ExchangeId: ID-SBMELW7W-06220-59960-1426051020468-0-4). Exhausted after delivery attempt: 1 caught: com.rabbitmq.client.AlreadyClosedException: channel is already closed due to channel error; protocol method: #method<channel.close>(reply-code=404, reply-text=NOT_FOUND - no exchange 'customerchannel.exchang' in vhost '/', class-id=60, method-id=40)
It looks like the first request is causing an error which closes the connection and logs the reason, and when you try to use the channel the second time it's returning an AlreadyClosedException with the message that caused the channel to close in the first call.
You can test this by trying to publish the second message to a different exchange name in the same channel and checking which exchange is in the error. E.g. publish the second message to invalidxchangename2 and you should still see invalidxchangename as the exchange in the error.
To fix, you should handle the publish result when you publish and re-establish the connection if there's an error.
If you want to be sure that a message got delivered to a RabbitMQ queue, then you have to use publisher confirms: https://www.rabbitmq.com/confirms.html
That you are able to publish a message it doesn't mean that the message will reach a queue. You could go to a mailbox and leave a letter inside, but between the time you left the letter there and a postman picked up, many things could have happened, for example, the mailbox catching fire and so on.
I have a bean producer and a bean consumer, used in a single route. The producer is spawned via a thread and listens for data on an hazelcast queue (it could be anything else, even randomly generated data locally I believe).
The data are sent to a seda endpoint, to ensure concurrency.
The consumer gets data and forwards it to another hazelcast queue. But again it could be anything else.
It works well but after a while, Camel shuts down and I can't find why.
Here are some of the messages I see:
Processing a lot of data...
[ main] MainSupport INFO Apache Camel 2.10.3 stopping
[ main] DefaultCamelContext INFO Apache Camel 2.10.3 (CamelContext: camel-1) is shutting down
[ main] DefaultShutdownStrategy INFO Starting to graceful shutdown 1 routes (timeout 300 seconds)
[el-1) thread #2 - ShutdownTask] DefaultShutdownStrategy INFO Waiting as there are still 1 inflight and pending exchanges to complete, timeout in 300 seconds.
then processing still during 300 seconds and stopping.
Here some of the code:
Producer:
public void run()
{
try
{
IRequest service = ProxyHelper.createProxy(context.getEndpoint("seda:echo"), IRequest.class);
BlockingQueue<Request> q = client.getQueue(MainApp.sQueueReceive);
while(true)
{
Request request;
request = q.take();
// no response awaited
service.request(request);
}
}
Consumer:
public void onMessage(Request request)
{
nb_forwarded++;
BlockingQueue<Request> q = MainApp.client.getQueue(MainApp.sQueueForward);
try
{
q.put(request);
}
catch (InterruptedException e)
{
exit(2); --> it does not happen
}
And finally, the route:
from("seda:echo")
.setExchangePattern(ExchangePattern.InOnly)
.bean(new HazelcastForwarder(), "onMessage");
It's in InOnly as no response is awaited from the producer, it is just a forward.
So why Camel is stopping. There is no message appart from those saying that it is stopping. Is there such a default behaviour in Camel. In which cases?
Thanks!
Enable DEBUG or Trace logging to reveil the true reason why camel is stopping. It can be that the enclosing container is stopping (if you are running camel inside something) or similar.
I was facing the similar issue, where Camel Context is closing immediately after starting the process. I am posting here so that it would also help others with similar issue.
In my case, I am using Spring for loading the Camel context using 'FileSystemXmlApplicationContext' and instantiating it with in try block,
try(AbstractXmlApplicationContext appContext = new FileSystemXmlApplicationContext(camelContextPath)) {
}
as my Eclipse was complaining about Resource leak. So, as soon as the call was coming out of the try/catch it was closing the Spring context, which again closing the Camel Context.
To fix the issue need to initialize Spring context out side the try block.
AbstractXmlApplicationContext appContext = null;
try {
appContext = new FileSystemXmlApplicationContext(camelContextPath);
}