Timed server events with ruby on rails

Question

I am attempting to create a web-based game in Ruby on Rails. I have a model named 'Game', which has a datetime in the database entry that corresponds to a time that I would like the server to call the Game model's update_game function. Depending on the game's settings, this could be every 30 seconds to every 12 hours.

Ruby on Rails only seems to work when it receives an HTTP request; is there a slick way to get my game to update on a periodic basis independent of HTTP requests?

Answer 1

I'd look into delayed_job for this. When the game starts, you can create a delayed_job for the first update, and every run after that can add a new job at the correct interval until it's done.

I'd do lots of testing though ;) - you don't want to let the jobs get away from you.

Answer 2

Rails itself doesn't do this; cron does this. Ruby does, however, have a gem named Whenever to make easier the declaration and deployment of new cron jobs.

However, if you are really going to expect a large amount of games to reliably update every 30 seconds, you may want to take a different approach if updating a game would take any significant amount of time. Perhaps once the game is accessed, the game could run the update as many times as necessary (e.g. if 3 minutes had passed and the interval is 30 seconds, run 6 updates once requested). This may or may not be a good option for your setup, however, so figure out which method is more viable for your purposes.

Answer 3

Look into background processing options and possibly cron.

Answer 4

I like the gem 'rufus-scheduler' which works within Rails, though I'm not sure you can programmatically add more tasks to it.