Best method for logging activity (Ruby on Rails)

I want to log the user activity through my Rails 2.3.8 application. I don't care what the activity is, just the last time any given user did anything on the site, including viewing pages, commenting, logging in, etc.

One method that I can think of is creating at last_active DateTime attribute in the user model and constantly updating this attribute based on a user's activity (or possibly taking advantage of the updated_at column). I could put an after_filter on every action of every controller to call an update method, but this see开发者_高级运维ms hacky and excessive. There must be a better way. Would an observer work? If so - how? Is there something built-in to Rails that I'm missing here?

Thanks!

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Put your after_filter on the ApplicationController. You can turn it off in other controllers with skip_after_filter as needed.