RESTful resource routing in Rails

Direct Answer

Rails resource routing maps HTTP method plus resource-shaped path to conventional controller actions and path helpers. resources :articles creates seven full-stack routes; an API usually limits that set to actions it exposes and omits the new and edit form routes.

Deep Dive & Architecture

A collection path has no record identifier. GET /articles lists the collection through index, while POST /articles submits a new representation to create. A member path includes :id. GET /articles/:id reads one record through show, PATCH or PUT sends changes to update, and DELETE requests destroy.

The remaining two routes exist to support server-rendered forms. GET /articles/new reaches new and displays a creation form. GET /articles/:id/edit reaches edit and displays an update form. They do not modify data. A JSON API with an independent client normally omits them using only, while a full Rails application can use all seven.

Route order matters because Rails chooses the first matching route. A custom path such as /articles/search placed after a broad member route may be interpreted as an ID in some route shapes. Prefer resourceful member or collection declarations, meaningful constraints, and bin/rails routes --expanded when diagnosing an unexpected match.

Nesting communicates ownership in the URL: /magazines/3/ads/8 says the ad is addressed through magazine 3. It can also duplicate information and force every child action to load a parent. Shallow routes or top-level resources are often clearer after one level. Use member routes for one existing resource and collection routes for operations over the set.

Routes are not authorization. A matching route only decides which code receives the request. The controller must still authenticate the caller, authorize the record or collection, validate parameters, and choose the response. Request specs should cover both routability and behaviour, especially when only, namespaces, version prefixes, or constraints define the public API surface. URL helpers should be preferred over hand-built strings because they follow the declared host, namespace, and parameter encoding rules.

When a command does not fit CRUD cleanly, first ask whether it creates a new resource or changes an existing one's state. A cancellation may be a state update; a long-running export may create an export resource. This often produces clearer retries, statuses, and audit history than an arbitrary verb endpoint.

Code Example

Rails.application.routes.draw do
  namespace :api do
    namespace :v1 do
      resources :articles, only: [:index, :show, :create, :update, :destroy] do
        get :preview, on: :member
        get :search, on: :collection
      end
    end
  end
end

The API omits form routes, then labels preview as member work and search as collection work.

Common Mistakes & Pitfalls

Using verbs in resource paths or confusing new/edit form routes with create/update operations.