Using JMS for long running file creation process for web application

Question

We have a requirement to allow users to generate search result exports in various formats. The problem is that the size of the exports can vary and take several seconds to minutes to complete. I want to allow users to be able to fire the request and continue doing other things while it runs, but I don't want to impair the web application server's performance by using background threads if necessary.

My initial idea is to decouple the web application and the generation process. I could use JMS with a message driven bean (MDB) that handles the file generation that is deployed separately from the web application; allowing to scale them individually based on future needs.

Technically, I see the web application maintaining a list of requests that it has started and sent JMS messages for. As the MDB completes, it sends updates back to a queue the web application listens on and updates the list of requests accordingly with status and perhaps file URI information. When user want to download a generated file they requested, the file is streamed to the browser and then removed.

As an added precaution, the MDB would also fire a delayed message into a cleanup queue that after the delay has expired, the MDB checks the URI of the generated file and if it continues to exist, removes the file and notifies the web application so it may update it's internal list accordingly perhaps by removing it or marking it as having been automatically removed.

The beauty here is if I need to increase the number of concurrent export jobs, I can easily spawn up another JMS client process or tweak the existing processes to run more concurrent MDB handlers without having to touch the web application itself.

I'm curious if there are other alternatives I could be overlooking, concerns I should be considering, or whether this is a solid decoupled solution that has worked for others in the past.

Answer 1

Given your scenario, i would do with session beans.

or there is JMX set up for jobs but they are legacy ways. i dont like jmx.

But just to let you know if these are limited report and needs once per day kind of, and simple form is to use quartz job, But i think you cant run if you can multiple job at same time.

well there are quartz job set up which are rally easy to set up , and you can trigger it from your application, and if you want some clean up , you can create multiple jobs and intelligent you can make them dependent. you can refer here for quartz set up .