Handle 404 not found error in API

app/controllers/api/errors_controller.rb

@@ -0,0 +1,7 @@
+module API
+  class ErrorsController < ApplicationController
+    def not_found
+      head :not_found
+    end
+  end
+end

config/routes.rb

@@ -8,6 +8,7 @@ Rails.application.routes.draw do
     resources :sessions, only: :create
     resources :sounds, only: :show
     resources :tracks, only: :index
+    match '*all', to: 'errors#not_found', via: :all
   end
 
   resources :playlists

spec/integration/api/application_spec.rb

@@ -18,4 +18,12 @@ describe 'API application' do
       expect(response.body).to be_empty
     end
   end
+
+  describe 'not found' do
+    it 'responds with a 404 when route does not exist' do
+      get '/api/not_found', format: :json
+      expect(response).to be_not_found
+      expect(response.body).to be_empty
+    end
+  end
 end