Overriding default parameters in Ruby on Rails with URL query strings

Question

This sounds like it should be a simple question, but here's the route:

get 'routes(/:start_system/:end_system(/:result_type))' => 'routes#calculate',
    :defaults => { :start_system => 'Jita', :end_system => 'Renyn', :result_type => 'short', :min_sec => -1.0 }

The defaults are overridden if I give a URL in this form (for example, we can use integers for the systems instead of their names):

host/routes/30000001/30001437

However, I am trying to provide more information in format strings after, which is not working:

host/routes/30000001/30001437?min_sec=0.5

Basically, the default { :min_sec => -1.0 } is never overridden by the format string at the end of the URL. Is this by design?

Answer 1

The defaults option is only working for params, which you explicitly specify in your route.

You could get the behaviour that you need by modifying your route like this:

get 'routes(/:start_system/:end_system(/:result_type)(/:min_sec))' => 'routes#calculate',
    defaults: { start_system: 'Jita', end_system: 'Renyn', result_type: 'short', min_sec: -1.0 }

Answer 2

Another approach which would maintain your design:

1. Remove default for min_sec from routes.rb .

2. Implement default in controller:

   def calculate min_sec = params['min_sec'] || -1.0 ... end