Fix `GET /api/v2/notifications/:id` and `POST /api/v2/notifications/:id/dismiss` for ungrouped notifications (#33990)

app/controllers/api/v2/notifications_controller.rb

@@ -46,7 +46,7 @@ class Api::V2::NotificationsController < Api::BaseController
   end
 
   def show
-    @notification = current_account.notifications.without_suspended.find_by!(group_key: params[:group_key])
+    @notification = current_account.notifications.without_suspended.by_group_key(params[:group_key]).take!
     presenter = GroupedNotificationsPresenter.new(NotificationGroup.from_notifications([@notification]))
     render json: presenter, serializer: REST::DedupNotificationGroupSerializer
   end
@@ -57,7 +57,7 @@ class Api::V2::NotificationsController < Api::BaseController
   end
 
   def dismiss
-    current_account.notifications.where(group_key: params[:group_key]).destroy_all
+    current_account.notifications.by_group_key(params[:group_key]).destroy_all
     render_empty
   end
 

app/models/concerns/notification/groups.rb

@@ -7,6 +7,10 @@ module Notification::Groups
   GROUPABLE_NOTIFICATION_TYPES = %i(favourite reblog follow).freeze
   MAXIMUM_GROUP_SPAN_HOURS = 12
 
+  included do
+    scope :by_group_key, ->(group_key) { group_key&.start_with?('ungrouped-') ? where(id: group_key.delete_prefix('ungrouped-')) : where(group_key: group_key) }
+  end
+
   def set_group_key!
     return if filtered? || GROUPABLE_NOTIFICATION_TYPES.exclude?(type)
 

spec/requests/api/v2/notifications_spec.rb

@@ -365,6 +365,18 @@ RSpec.describe 'Notifications' do
         .to start_with('application/json')
     end
 
+    context 'with an ungrouped notification' do
+      let(:notification) { Fabricate(:notification, account: user.account, type: :favourite) }
+
+      it 'returns http success' do
+        get "/api/v2/notifications/ungrouped-#{notification.id}", headers: headers
+
+        expect(response).to have_http_status(200)
+        expect(response.content_type)
+          .to start_with('application/json')
+      end
+    end
+
     context 'when notification belongs to someone else' do
       let(:notification) { Fabricate(:notification, group_key: 'foobar') }
 
@@ -396,6 +408,19 @@ RSpec.describe 'Notifications' do
       expect { notification.reload }.to raise_error(ActiveRecord::RecordNotFound)
     end
 
+    context 'with an ungrouped notification' do
+      let(:notification) { Fabricate(:notification, account: user.account, type: :favourite) }
+
+      it 'destroys the notification' do
+        post "/api/v2/notifications/ungrouped-#{notification.id}/dismiss", headers: headers
+
+        expect(response).to have_http_status(200)
+        expect(response.content_type)
+          .to start_with('application/json')
+        expect { notification.reload }.to raise_error(ActiveRecord::RecordNotFound)
+      end
+    end
+
     context 'when notification belongs to someone else' do
       let(:notification) { Fabricate(:notification, group_key: 'foobar') }