Rails | nested routes if nil - ruby-on-rails

Question

I have used friendly_id and globalize gem. So I can generate routes as;
/search/france/weekly/toyota-95
Here is my routes;
namespace :search do
resources :car_countries, path: '', only: [] do
resources :rental_types, path: '', only: [] do
resources :car_types, path: '', only: [:show] do
end
end
end
end
But the thing is now I would like to also get city either;
/search/nice/weekly/toyota-95
or
/search/france/nice/weekly/toyota-95
The problem is I want to have both with city name and without city name (only country). They should go to same controller which is at the end car_types.
So if I add car_cities to routes, I get error when there is no city but only country.
namespace :search do
resources :car_countries, path: '', only: [] do
resources :car_cities, path: '', only: [] do
resources :rental_types, path: '', only: [] do
resources :car_types, path: '', only: [:show] do
end
end
end
end
resources :car_countries, path: '', only: [] do
resources :rental_types, path: '', only: [] do
resources :car_types, path: '', only: [:show] do
end
end
end
end
How can I do that?

Answer 1

As Gerry says, take a look at route globbing http://guides.rubyonrails.org/routing.html#route-globbing-and-wildcard-segments. I'd suggest to send everything to a single controller action and either do stuff there or delegate it to a search model/service object (depends on your taste).
Example:
# in config/routes.rb
get 'search/*q' => 'searches#show'
# in app/controllers/searches_controller.rb
class SearchesController < ApplicationController
def search
# This should work for your simple use case but it will become pretty confusing if you add more filters.
search_params = params[:search].split('/')
if search_params.count == 4
country, city, rental_type, car_type = search_params
else
country, rental_type, car_type = search_params
end
# Do whatever with these variables, e.g. Car.for_country(country)...
end
end
A more stable solution would be to make use of the fact that rental types are probably a closed set (daily, weekly, ...) and use segment constraints for this part in the routes:
# config/routes.rb
scope to: 'searches#show', constraints: { rental_type: /(daily|weekly|monthly)/ } do
get '/search/:country/:rental_type/:car_type'
get '/search/:country/:city/:rental_type/:car_type'
end
This should differentiate the two URLs based on the fact that :city can never match the rental type constraint.
Yet another option would be to use a full blown constraints object (http://guides.rubyonrails.org/routing.html#advanced-constraints):
# config/routes.rb
class SearchConstraint
def initialize
# assuming that all your objects have the friendly_id on the name field
#country_names = %w[austria germany]
#rental_type_names = %w[daily weekly monthly]
#car_type_names = %w[toyota-prius vw-golf]
#city_names = %w[innsbruck munich berlin]
end
def matches?(request)
checks = []
# only check for parts if they're actually there
checks << #country_names.include?(request.parameters[:country]) if request.parameters[:country].present?
checks << #rental_type_names.include?(request.parameters[:rental_type]) if request.parameters[:rental_type].present?
checks << #car_type_names.include?(request.parameters[:car_type]) if request.parameters[:car_type].present?
checks << #city_names.include?(request.parameters[:city]) if request.parameters[:city].present?
checks.all? # or, if you want it more explicit: checks.all? { |result| result == true }
end
end
scope to: 'searches#show', constraints: SearchConstraint.new do
get '/search/:country/:rental_type/:car_type'
get '/search/:country/:city/:rental_type/:car_type'
end
Note that this last approach is probably the cleanest and least hacky approach (and it's quite easy to test) but it also comes at the cost if involving the database in every request to these particular URLs and the URLs fail hard if there's an issue with the database connection.
Hope that helps.