Asynchronous delivery support using Apache Camel routes and ActiveMQ

2
votes

Please help me in finalizing architecture for Asynchronous delivery support using Apache Camel and ActiveMQ and below I have explained point by point basis about my requirement.

  1. I have Jetty Server receiving incoming messages and ActiveMQ to store it in disk using Kaha DB.

  2. Active MQ sends ack once it stores in kaha DB back to client.

  3. I have Spring AbstractPollingMessageListenerContainer JMS Message listener which picks up the message from activemq queue every 1 second and dispatch to Camel HTTP endpoints and then finally sent to actual remote receivers. Once Dispatcher thread gets response from remote receivers it deletes message from ActiveMQ.

  4. Assume that I have many slow remote receivers in that case my Dispatcher thread created by AbstractPollingMessageListenerContainer remains blocked until I get response from remote receivers. This results to creation of new Dispatcher threads since already created Dispatcher threads are not able to dispatch new messages from ActiveMQ queue. Now creation of many Dispatcher threads result into more CPU usage which impacts overall performance.

  5. Now my requirement is I want Dispatcher thread only to dispatch messages from ActiveMQ queue to HTTP endpoint and forget and also not do acknowledgement so that message is still in queue. Also I will not let Dispatcher thread to wait till I get response so I have thought to handle response using separate thread and this same thread will only delete message from ActiveMQ queue.

  6. So my current architecture is like below:

    Camel Jetty Server ----> ActiveMQ queue ----> Dispatcher Thread ---> Camel Direct endpoint ----> Camel HTTP endpoint ---> remote receivers sending response back ---> response ---> Dispatcher Thread (sends ack to delete messages from ActiveMQ queue) ----> ActiveMQ Queue.

    Here I feel since we are using Direct endpoint which is synchronous so Dispatcher thread remains active till it gets response and so same dispatcher thread is not able to process further new message from ActiveMQ queue.

    Please suggest if some thing else I can use here to avoid Direct endpoint.

    I used SEDA endpoint but drawback is it processes 1 message using 1 thread and also gets blocked till it gets response from receivers. In this approach previously Dispatcher thread gets blocked but now Seda consumer threads gets blocked and could not dispatch new messages from in memory queue of SEDA towards remote receivers.

  7. I feel some kind of design which helps me in keep on sending message to remote receivers and only when response comes back some daemeon thread gets notified and it will handle acknowledgement towards activeMQ. Also I thought to use NIO framework implementation like Camel netty/netty4-http component but could not find exact usage and how to fit it in current architecture.

  8. Modified architecture should be like below: Camel Jetty Server ----> ActiveMQ queue ----> Dispatcher Thread--->Unknown Stuff ----> Camel HTTP Endpoint ---> remote receivers sending response back--->Unknown Stuff (sends ack to delete messages from ActiveMQ queue) ----> ActiveMQ Queue

Please help me in finalising Unknown Stuff and I am posting my query after doing enough R & D.

Also new ideas are welcome and please give me idea with a restriction that I must persist the message and delete it only after getting success response from remote receiver. Also I have to design architecture only using Apache Camel routes. Route Definitions: 1. Dispatcher Route: from(fromUri)to(toUris); fromUri: [ActiveMQueue.http1270018081testEndpoint1:queue:ActiveMQueue?maxConcurrentConsumers=15&concurrentConsumers=3&maxMessagesPerTask=10&messageListenerContainerFactoryRef=AbstractPollingMessageListenerContainer ] ToUris: [ActiveMQ.DLQ:queue:ActiveMQ.DLQ, direct:http1270018081testEndpoint1]

2.Remote Receiver Proxy Route: fromUri:direct:http1270018081testEndpoint1 from(fromUri).to(toUri).process(responseProcessor) toUri:http://127.0.0.1:8081/testEndpoint1?bridgeEndpoint=true responseProcessor: To process response received by remote receiver.

Overall Route looks like below: Dispatcher Route---> Remote Receiver Route---> Remote Server

1
apache-camelactivemqnettyspring-jms
Can you post your route definitions please ? It would be easier to understand... - Alexandre Cartapanis
@AlexandreCartapanis I have added route definitions in my question only since I can't add it in comment since it's too long to put in comment and thanks a lot in advance to help me. - Prakash Chandra
Take a look at wire tap EIP - Claus Ibsen
@Claus Ibsen Can you please elaborate how I can fit wire tap EIP for my requirement. - Prakash Chandra
I have posted my further development regarding the same in separate post: stackoverflow.com/questions/37590436/… Please look into this post and reply if my understanding regarding netty4-http component is correct or not. - Prakash Chandra

1 Answers

0
votes

JMS message acknowledgement is done under the covers, so your only way to really "send the acknowledgement back to the queue" is to use a JMS transaction (doesn't need to be XA)

It sounds like a LLR-style transaction would be useful and drastically simplify things for you. If you consume the message from the queue using a JMS-local transaction, and only have one other endpoint, the message will only be acknowledged and removed from the queue when the http send is completed-- even though HTTP doesn't support transactions. You can then have a number of concurrent consumers to run in parallel and combine with throttling to help with rate limiting.

from: amq:queue:INPUT.REQUESTS?.. concurrentConsumers.. and transacted enabled
throttle
to: http://url