Add event and metric for access to service ping endpoint

config/events/request_service_ping_via_rest.yml

+---
+description: Service Ping was requested via REST API endpoint
+category: InternalEventTracking
+action: request_service_ping_via_rest
+product_section: analytics
+product_stage: monitor
+product_group: analytics_instrumentation
+milestone: '16.9'
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/143385/
+distributions:
+- ce
+- ee
+tiers:
+- free
+- premium
+- ultimate

config/metrics/counts_28d/count_total_request_service_ping_via_rest_monthly.yml

+---
+key_path: counts.count_total_request_service_ping_via_rest_monthly
+description: Monthly count of requests for Service Ping payload via REST API
+product_section: analytics
+product_stage: monitor
+product_group: analytics_instrumentation
+performance_indicator_type: []
+value_type: number
+status: active
+milestone: '16.9'
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/143385/
+time_frame: 28d
+data_source: internal_events
+data_category: optional
+distribution:
+- ce
+- ee
+tier:
+- free
+- premium
+- ultimate
+options:
+  events:
+  - request_service_ping_via_rest
+events:
+- name: request_service_ping_via_rest

config/metrics/counts_7d/count_total_request_service_ping_via_rest_weekly.yml

+---
+key_path: counts.count_total_request_service_ping_via_rest_weekly
+description: Weekly count of requests for Service Ping payload via REST API
+product_section: analytics
+product_stage: monitor
+product_group: analytics_instrumentation
+performance_indicator_type: []
+value_type: number
+status: active
+milestone: '16.9'
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/143385/
+time_frame: 7d
+data_source: internal_events
+data_category: optional
+distribution:
+- ce
+- ee
+tier:
+- free
+- premium
+- ultimate
+options:
+  events:
+  - request_service_ping_via_rest
+events:
+- name: request_service_ping_via_rest

lib/api/usage_data.rb

@@ -36,6 +36,8 @@ class UsageData < ::API::Base
         get do
           content_type 'application/json'
 
+          Gitlab::InternalEvents.track_event('request_service_ping_via_rest', user: current_user)
+
           Rails.cache.fetch(Gitlab::Usage::ServicePingReport::CACHE_KEY) ||
             ::RawUsageData.for_current_reporting_cycle.first&.payload || {}
         end

spec/requests/api/usage_data_spec.rb

@@ -60,6 +60,13 @@
 
         expect(response.body).to eq(usage_data.to_json)
       end
+
+      it 'tracks an internal event' do
+        expect(Gitlab::InternalEvents).to receive(:track_event)
+          .with('request_service_ping_via_rest', user: user)
+
+        get api(endpoint, personal_access_token: personal_access_token)
+      end
     end
   end