Sending params to GET request in Ruby on Rails 2.3.x - ruby-on-rails

Question

I'm new to rails and I'm currently using 2.3.8. I'm designing a web service for an iOS app.
As I'm normally a client side iPhone developer, my knowledge of server side implementation is shamefully minimal.
The problem I'm having is that I'm trying to pass some params in a GET request to the index action in one of my controllers. This is routed using the default
map.resources :dishes
where dishes is the name of the controller, created with scaffold.
I would like to pass multiple params to either a new action or to the index, which will allow me to filter the dish objects to return.
The index method looks like
def index
if(params[:latitude])
#min = 0.5 - 1
#max = 0.5 + 1
#locations = Location.find(:all, :conditions => [":latitude > ? AND :latitude < ?", #min, #max])
#dishes = new Array
#locations.each do |loc|
#dishes = #dishes + loc.dishes
end
respond_to do |format|
format.html # index.html.erb
format.json {render :json => #dishes.to_json(:except => [ :user_id, :location_id , :like_id], :include => { :user => { :only => [:id, :name] } } ) }
end
else
#dishes = Dish.all
respond_to do |format|
format.html # index.html.erb
format.json {render :json => #dishes.to_json(:except => [ :user_id, :location_id , :like_id], :include => { :user => { :only => [:id, :name] } } ) }
end
end
end
I am currently getting the following error when I pass in an extra param
ArgumentError in DishesController#index
wrong number of arguments (1 for 0)
The full error:
ArgumentError in DishesController#index
wrong number of arguments (1 for 0)
RAILS_ROOT: /Users/jon/Documents/Dev/Research/FF5_Rails_Test/FF5
Application Trace | Framework Trace | Full Trace
/Users/jon/Documents/Dev/Research/FF5_Rails_Test/FF5/app/controllers/dishes_controller.rb:9:in `new'
/Users/jon/Documents/Dev/Research/FF5_Rails_Test/FF5/app/controllers/dishes_controller.rb:9:in `index'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/base.rb:1331:in `send'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/base.rb:1331:in `perform_action_without_filters'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/filters.rb:617:in `call_filters'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/filters.rb:610:in `perform_action_without_benchmark'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/benchmarking.rb:68:in `perform_action_without_rescue'
/Library/Ruby/Gems/1.8/gems/activesupport- 2.3.8/lib/active_support/core_ext/benchmark.rb:17:in `ms'
/Library/Ruby/Gems/1.8/gems/activesupport-2.3.8/lib/active_support/core_ext/benchmark.rb:17:in `ms'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/benchmarking.rb:68:in `perform_action_without_rescue'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/rescue.rb:160:in `perform_action_without_flash'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/flash.rb:151:in `perform_action'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/base.rb:532:in `send'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/base.rb:532:in `process_without_filters'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/filters.rb:606:in `process'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/base.rb:391:in `process'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/base.rb:386:in `call'
/Library/Ruby/Gems/1.8/gems/actionpack-2.3.8/lib/action_controller/routing/route_set.rb:438:in `call'
Request
Parameters:
{"format"=>"json",
"latitude"=>"0.5"}
Show session dump
Response
Headers:
{"Content-Type"=>"",
"Cache-Control"=>"no-cache"}
I realise this goes slightly against the RESTful design of Rails but I couldn't work out another way to do it.
Again, I'm a new to rails / web service dev so if you have any tips I would welcome them.
Thanks.

Answer 1

You have
#dishes = new Array
which is not Ruby unfortunately :) There are three ways to create an instance of Array
#dishes = Array.new
#dishes = []
#dishes = Array( nil )
also pay attention to
/Users/jon/Documents/Dev/Research/FF5_Rails_Test/FF5/app/controllers/dishes_controller.rb:9:in 'new'
/Users/jon/Documents/Dev/Research/FF5_Rails_Test/FF5/app/controllers/dishes_controller.rb:9:in 'index'
which tells you that error happened in new not in index