Rails Routing with Query String - ruby-on-rails

Question

I have a problem where I need values passed in from a GET request and I don't know how to set up the routing definition.
My Category object has a type(string),a color(string) and many products. I want to create a simple web service that lets the caller get all of a Category's products by passing in the Category's type and color:
http://www.myapp.com/getProducts?catType=toy&color=red
or ?
http://www.myapp.com/categories/getProducts?catType=toy&color=red
How do I define the correct routing for this situation? Are there better ways to do this in a Restful manner... because I know that Rails is Restful, so if there is a way to do it "correctly" then that would be even better.
Thanks

Answer 1

Your first example:
map.getproduct '/getProduct', :controller => 'your_controller', :action => 'your_action'
In controller you will have catType and color in params hash:
params[:catType]
=> 'toy'
params[:color]
=> 'red'
Is there better way? Probably yes, but it depends on your needs. If you will always have catType and color parameters, than you can add route like this:
map.getproduct '/getProduct/:catType/:color', :controller => 'your_controller', :action => 'your_action'
You will have access to those parameters with params hash like in previous example. And your urls will look like this:
www.myapp.com/getProduct/toy/red
If your parameters may change, you can use route globbing:
map.getproduct '/getProduct/*query', :controller => 'your_controller', :action => 'your_action'
Then it will catch all request that has www.my.app.com/getProduct/... at the begining. But you will have more work in controller. You will have access to query with this:
params[:query]
and for www.myapp.com/getProduct/color/red/catType/toy it will give:
params[:query]
=> ['color', 'red', 'catType', 'toy]
So you have to parse it manualy.

Answer 2

One RESTful way to to do this would involve a product resource nested beneath a category resource, like so:
http://www.myapp.com/categories/toy/products?color=red
Your routes.rb would need to contain:
map.resources :categories do |category|
category.resources :products
end
Since my url above using the Category's type attribute for routing, I'm implying that each type is unique, like an id. It'll mean that whenever you're loading a category in the Categories controller (or anywhere else) you'll need to load the category with Category.find_by_type(params[:id]) instead of Category.find(params[:id]). I like routing categories this way whenever possible.
Your ProductsController controller index action would find products using lines like:
#category = Category.find_by_type(params[:category_id])
#products = #category.products.find(:all, :conditions => { :color => params[:color]} )
Remember, your Category model must contain the line:
has_many :products
It's probable a good idea to enforce that in the model with validations:
validates_presence_of :type
validates_uniqueness_of :type
To make routing work you should also overwrite the to_param method in the Category model to return type instead of id:
def to_param
self.type
end