Address reviewer's feedback

- rename metric to search_unique_visits_for_any_target_weekly
- remove to_date calls
- replace Date.today with Date.current

app/controllers/search_controller.rb

@@ -4,12 +4,15 @@ class SearchController < ApplicationController
   include ControllerWithCrossProjectAccessCheck
   include SearchHelper
   include RendersCommits
+  include RedisTracking
 
   SCOPE_PRELOAD_METHOD = {
     projects: :with_web_entity_associations,
     issues: :with_web_entity_associations
   }.freeze
 
+  track_redis_hll_event :show, name: 'i_search_total', feature: :search_track_unique_users
+
   around_action :allow_gitaly_ref_name_caching
 
   skip_before_action :authenticate_user!
@@ -126,3 +129,5 @@ class SearchController < ApplicationController
     payload[:metadata]['meta.search.scope'] = params[:scope]
   end
 end
+
+SearchController.prepend_if_ee('EE::SearchController')

changelogs/unreleased/238116-redis-hll-search-analytics.yml

+---
+title: Add the unique search visits data to the usage ping
+merge_request: 40134
+author:
+type: changed

config/feature_flags/development/search_track_unique_users.yml

+---
+name: search_track_unique_users
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/40134
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/240906
+group: group::global search
+type: development
+default_enabled: false

ee/app/controllers/ee/search_controller.rb

+# frozen_string_literal: true
+
+module EE
+  module SearchController
+    extend ActiveSupport::Concern
+
+    prepended do
+      before_action :track_advanced_search, only: :show, if: -> { request.format.html? && request.headers['DNT'] != '1' }
+    end
+
+    private
+
+    def track_advanced_search
+      # track unique users of advanced global search
+      track_unique_redis_hll_event("i_search_advanced", :search_track_unique_users) if search_service.use_elasticsearch?
+
+      # track unique users who search against paid groups/projects
+      track_unique_redis_hll_event("i_search_paid", :search_track_unique_users) if (search_service.project || search_service.group)&.feature_available?(:elastic_search)
+    end
+  end
+end

ee/spec/controllers/ee/search_controller_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe SearchController do
+  let_it_be(:user) { create(:user) }
+
+  before do
+    sign_in(user)
+  end
+
+  describe 'GET #show' do
+    context 'unique users tracking', :elastic do
+      before do
+        stub_ee_application_setting(elasticsearch_search: true, elasticsearch_indexing: true)
+        allow(Gitlab::UsageDataCounters::HLLRedisCounter).to receive(:track_event)
+      end
+
+      context 'i_search_advanced' do
+        it_behaves_like 'tracking unique hll events', :show do
+          let(:request_params) { { scope: 'projects', search: 'term' } }
+          let(:target_id) { 'i_search_advanced' }
+        end
+      end
+
+      context 'i_search_paid' do
+        let(:group) { create(:group) }
+
+        before do
+          allow(group).to receive(:feature_available?).with(:elastic_search).and_return(true)
+        end
+
+        it_behaves_like 'tracking unique hll events', :show do
+          let(:request_params) { { group_id: group.id, scope: 'blobs', search: 'term' } }
+          let(:target_id) { 'i_search_paid' }
+        end
+      end
+    end
+  end
+end

lib/gitlab/usage_data.rb

@@ -38,6 +38,7 @@ module Gitlab
             .merge(usage_activity_by_stage(:usage_activity_by_stage_monthly, last_28_days_time_period))
             .merge(analytics_unique_visits_data)
             .merge(compliance_unique_visits_data)
+            .merge(search_unique_visits_data)
         end
       end
 
@@ -608,6 +609,18 @@ module Gitlab
         { compliance_unique_visits: results }
       end
 
+      def search_unique_visits_data
+        events = ::Gitlab::UsageDataCounters::HLLRedisCounter.events_for_category('search')
+        results = events.each_with_object({}) do |event, hash|
+          hash[event] = redis_usage_data { ::Gitlab::UsageDataCounters::HLLRedisCounter.unique_events(event_names: event, start_date: 7.days.ago.to_date, end_date: Date.current) }
+        end
+
+        results['search_unique_visits_for_any_target_weekly'] = redis_usage_data { ::Gitlab::UsageDataCounters::HLLRedisCounter.unique_events(event_names: events, start_date: 7.days.ago.to_date, end_date: Date.current) }
+        results['search_unique_visits_for_any_target_monthly'] = redis_usage_data { ::Gitlab::UsageDataCounters::HLLRedisCounter.unique_events(event_names: events, start_date: 4.weeks.ago.to_date, end_date: Date.current) }
+
+        { search_unique_visits: results }
+      end
+
       def action_monthly_active_users(time_period)
         counter = Gitlab::UsageDataCounters::TrackUniqueEvents
 

lib/gitlab/usage_data_counters/known_events.yml

@@ -84,3 +84,15 @@
   redis_slot: edit
   expiry: 29
   aggregation: daily
+- name: i_search_total
+  category: search
+  redis_slot: search
+  aggregation: weekly
+- name: i_search_advanced
+  category: search
+  redis_slot: search
+  aggregation: weekly
+- name: i_search_paid
+  category: search
+  redis_slot: search
+  aggregation: weekly

spec/controllers/search_controller_spec.rb

@@ -149,6 +149,11 @@ RSpec.describe SearchController do
       expect(assigns[:search_objects].first).to eq note
     end
 
+    it_behaves_like 'tracking unique hll events', :show do
+      let(:request_params) { { scope: 'projects', search: 'term' } }
+      let(:target_id) { 'i_search_total' }
+    end
+
     context 'on restricted projects' do
       context 'when signed out' do
         before do

spec/lib/gitlab/usage_data_spec.rb

@@ -1020,6 +1020,32 @@ RSpec.describe Gitlab::UsageData, :aggregate_failures do
     end
   end
 
+  describe '.search_unique_visits_data' do
+    subject { described_class.search_unique_visits_data }
+
+    before do
+      described_class.clear_memoization(:unique_visit_service)
+      events = ::Gitlab::UsageDataCounters::HLLRedisCounter.events_for_category('search')
+      events.each do |event|
+        allow(::Gitlab::UsageDataCounters::HLLRedisCounter).to receive(:unique_events).with(event_names: event, start_date: 7.days.ago.to_date, end_date: Date.current).and_return(123)
+      end
+      allow(::Gitlab::UsageDataCounters::HLLRedisCounter).to receive(:unique_events).with(event_names: events, start_date: 7.days.ago.to_date, end_date: Date.current).and_return(543)
+      allow(::Gitlab::UsageDataCounters::HLLRedisCounter).to receive(:unique_events).with(event_names: events, start_date: 4.weeks.ago.to_date, end_date: Date.current).and_return(987)
+    end
+
+    it 'returns the number of unique visits to pages with search features' do
+      expect(subject).to eq({
+        search_unique_visits: {
+          'i_search_total' => 123,
+          'i_search_advanced' => 123,
+          'i_search_paid' => 123,
+          'search_unique_visits_for_any_target_weekly' => 543,
+          'search_unique_visits_for_any_target_monthly' => 987
+        }
+      })
+    end
+  end
+
   describe '.service_desk_counts' do
     subject { described_class.send(:service_desk_counts) }
 

spec/support/shared_examples/controllers/unique_hll_events_examples.rb

+# frozen_string_literal: true
+
+RSpec.shared_examples 'tracking unique hll events' do |method|
+  it 'tracks unique event if the format is HTML' do
+    expect(Gitlab::UsageDataCounters::HLLRedisCounter).to receive(:track_event).with(instance_of(String), target_id)
+
+    get method, params: request_params, format: :html
+  end
+
+  it 'tracks unique event if DNT is not enabled' do
+    expect(Gitlab::UsageDataCounters::HLLRedisCounter).to receive(:track_event).with(instance_of(String), target_id)
+    request.headers['DNT'] = '0'
+
+    get method, params: request_params, format: :html
+  end
+
+  it 'does not track unique event if DNT is enabled' do
+    expect(Gitlab::UsageDataCounters::HLLRedisCounter).not_to receive(:track_event).with(instance_of(String), target_id)
+    request.headers['DNT'] = '1'
+
+    get method, params: request_params, format: :html
+  end
+
+  it 'does not track unique event if the format is JSON' do
+    expect(Gitlab::UsageDataCounters::HLLRedisCounter).not_to receive(:track_event).with(instance_of(String), target_id)
+
+    get method, params: request_params, format: :json
+  end
+end