Check if license exists before checking the addon.

lib/gitlab/usage_data.rb

@@ -54,7 +54,9 @@ module Gitlab
       end
 
       def service_desk_counts
-        return {} unless ::License.current.add_on?('GitLab_ServiceDesk')
+        license = ::License.current
+        return {} if license.nil?
+        return {} unless license.add_on?('GitLab_ServiceDesk')
 
         projects_with_service_desk = Project.where(service_desk_enabled: true)
 

spec/lib/gitlab/usage_data_spec.rb

@@ -103,6 +103,12 @@ describe Gitlab::UsageData do
       end
     end
 
+    context 'when there is no license' do
+      it 'returns an empty hash' do
+        expect(subject).to eq({})
+      end
+    end
+
     context 'when Service Desk is enabled' do
       it 'gathers Service Desk data' do
         create_list(:issue, 3, confidential: true, author: User.support_bot, project: [project3, project4].sample)