How can I make my custom url helpers in rails?

Question

I'd like this custom url helper to be accessible from controllers, views, tests... Ending with both _url and _path. Also it should have the possibility to add parameters at the end as a url helper.

def reviews(reviewable)
  "/reviews/#{reviewable.class}/#{reviewable.id}"
end
reviews_url Book.find(1) # /reviews/Book/1
reviews_path Film.find(3) # /reviews/Film/3

Review.reviewable is polymorphic.

config/routes

get "reviews/:reviewable_type/:reviewable_id" => "reviews#index"

Answer 1

I would just define the routes as:

resources :books do
  resources :reviews, only: [:new, :create, :index]
end

resources :films do
  resources :reviews, only: [:new, :create, :index]
end

This will create the routes as:

books/:book_id/reviews
films/:film_id/reviews

This is the conventional RESTful way to define nested resources . And more importantly it works with the Rails polymorphic route helpers .

You can use routing concerns to DRY it if needed.

concern :reviewable do
  resources :reviews, only: [:new, :create, :index]
end

resources :books, concerns: :reviewable
resources :films, concerns: :reviewable

It gives you the named route helpers book_reviews_path(@book) and film_reviews_path(@film) . You can also use the polymorphic route helpers:

<%= link_to "Reviews for #{@reviewable.title}" [@reviewable, :reviews] %>
...
<%= form_for([@reviewable, @reviewable.review.new]) do %>
...
redirect_to [@reviewable, :reviews], notice: 'Review created'

Answer 2

Even though my question has been answered a long time ago, I want to add another answer according to the title of the question. So if you actually want to create custom url and path helpers, here's the answer with an example: Generating a full resourceful path giving only the last resource to the routes helper

Rails docs: https://api.rubyonrails.org/classes/ActionDispatch/Routing/Mapper/CustomUrls.html#method-i-direct