Question

I am making a rails app and I am wondering whether it is possible to setup an asynchronous/callback architecture in the controller layer. I am trying to do the following:

When a HTTP request is made to /my_app/foo, I want to asynchronously dish out two jobs – a naive ranking job and a complicated ranking job both of which rank 1000 posts – to several worker machines. I want to setup a callback method in the controller for each job which is called when the respective job is finished. If the complicated job does not return within X milliseconds, I want to return the output from the naive job. Otherwise, I want to return the output from the complicated job.

It is important to note that I want these jobs to performed in parallel. What is the best way to implement such a system in Rails? I am using Apache Phusion Passenger as my rails server if that helps.

Thanks.

Answer 1

It’s possible to issue several HTTP request asynchronously in Rails. However, it’s impossible to make Rails event-driven.

In can send several HTTP request asynchronously with libraries such as Typhoeus. However, you might have concurrency issue if your timeout is too long.

Otherwise, you can try some event-driven web framework such as Cramp and Goliath. They are both based on EventMachine, so you can try em-http-request.