Carl Mercier’s blog

In case you forgot, Montreal on Rails #2 is tonight! Hope to see you there.

Here’s the geekiest thing I’ve seen this week (and I love it!) A Rails vs. Java ad, Mac/PC style!

I am in a situation where I need a single method to perform miscellaneous operations from different controllers. I am using RESTful routes and I ran into the problem where the last ID in the URL has to be accessed by params[:id] instead of params[:controller_id] like the other IDs of the same URL.

In a nutshell, I had:

URL: /families/1/people/5

However, for the sake of simplicity and to be able to use the method in question from other controllers (ex: /families/1/people/5/friends/7) without any modifications, I wanted to do person_id = params[:person_id] regardless of which controller was being accessed.

This was fairly easy to fix and I rolled out a little helper method I call smart_params:

I put it in /app/controllers/application.rb and added before_filter :smart_params to the class. Voila! Unified and consistent params for your IDs!

I don’t know if you’ll find this useful for anybody else, but it’s saving me a lot of time.

EDITS:

March 3, 2007: modified smart_params slightly to avoid creating a new nil param when params[:id] does not exist.