Question

I have a controller that generates HTML, XML, and CSV reports. The queries used for these reports take over a minute to return their result.

What is the best approach to run these tasks in the background and then return the result to the user? I have looked into Backgroundrb. Is there anything more basic for my needs?

Answer 1

You could look at using DelayedJob to perform those queries for you, and have an additional table called “NotificationQueue”. When a job is finished (with its resultset), store the resultset and the User ID of the person who made that query in the NotificationQueue table. then on every page load (and, if you like, every 15-20 seconds), poll that database and see if there are any completed queries.

DelayedJob is really great because you write your code as if it wasn’t going to be a delayed job, and just change the code to do the following:

#Your method
Query.do_something(params)

#Change to
Query.send_later(:do_something, params)

We use it all the time at work, and it works great.