Return JSON response from 404

app/controllers/api/v1/base_controller.rb

@@ -1,6 +1,8 @@
 module Api
   module V1
     class BaseController < ActionController::API
+      rescue_from ActiveRecord::RecordNotFound, with: :not_found_error
+
       private
 
       def authenticate
@@ -8,6 +10,12 @@ module Api
         head :unauthorized unless ip_allowed
       end
 
+      def not_found_error
+        uuid = params['uuid']
+        json = { error: 'Not Found', uuid: uuid, message: 'Record not found' }
+        render json: json, status: :not_found
+      end
+
       def allowed_ips
         ENV['auction_api_allowed_ips'].split(',').map(&:strip)
       end

test/integration/api/v1/auctions/details_test.rb

@@ -25,8 +25,11 @@ class ApiV1AuctionDetailsTest < ActionDispatch::IntegrationTest
   end
 
   def test_auction_not_found
-    assert_raises ActiveRecord::RecordNotFound do
+    expected_uuid = 'not-a-real-path'
-      get api_v1_auction_path('non-existing-uuid'), as: :json
+    get api_v1_auction_path(expected_uuid), as: :json
-    end
+    assert_response :not_found
+    json = JSON.parse(response.body, symbolize_names: true)
+    assert_equal expected_uuid, json[:uuid]
+    assert_equal 'Not Found', json[:error]
   end
-end
+end

test/integration/api/v1/auctions/update_test.rb

@@ -141,10 +141,14 @@ class ApiV1AuctionUpdateTest < ActionDispatch::IntegrationTest
   end
 
   def test_auction_not_found
-    assert_raises ActiveRecord::RecordNotFound do
+    expected_uuid = 'non-existing-uuid'
-      patch api_v1_auction_path('non-existing-uuid'),
+    patch api_v1_auction_path(expected_uuid),
-            params: { status: Auction.statuses[:no_bids] },
+          params: { status: Auction.statuses[:no_bids] },
-            as: :json
+          as: :json
-    end
+
+    assert_response :not_found
+    json = JSON.parse(response.body, symbolize_names: true)
+    assert_equal expected_uuid, json[:uuid]
+    assert_equal 'Not Found', json[:error]
   end
 end