Track unique visits to analytics pages

Do not track if DNT is enabled
Add unique visits data to usage ping

Track visit to contribution analytics page

Introduce enum for target_id encoding

Track unique visits to analytics pages

The list of pages to track is in the MR
description

Add a count for any analytics page visit

Expire cookie in 24 months

Refactor the method tracking unique visits

To make it more succint in controllers and
more readable

Add NOT NULL constraint to last_visited_at column

Add a feature flag

Track only if user is signed in

Refactor tests by using shared examples

Use GL batch count for counting visits

Use Redis instead of Postgres

Implement unique visit tracking with
Redis HyperLogLog

Do not track visit if DNT in enabled

And let the user to opt-out

Add the unique visits data to the usage ping

Add new statistics to usage ping documentation

Move unique visits out of service class

Change changelog merge request number

app/controllers/dashboard/todos_controller.rb

@@ -3,11 +3,14 @@
 class Dashboard::TodosController < Dashboard::ApplicationController
   include ActionView::Helpers::NumberHelper
   include PaginatedCollection
+  include Analytics::UniqueVisitsHelper
 
   before_action :authorize_read_project!, only: :index
   before_action :authorize_read_group!, only: :index
   before_action :find_todos, only: [:index, :destroy_all]
 
+  track_unique_visits :index, target_id: 'u_analytics_todos'
+
   def index
     @sort = params[:sort]
     @todos = @todos.page(params[:page])

app/controllers/instance_statistics/cohorts_controller.rb

 # frozen_string_literal: true
 
 class InstanceStatistics::CohortsController < InstanceStatistics::ApplicationController
+  include Analytics::UniqueVisitsHelper
+
   before_action :authenticate_usage_ping_enabled_or_admin!
 
+  track_unique_visits :index, target_id: 'i_analytics_cohorts'
+
   def index
     if Gitlab::CurrentSettings.usage_ping_enabled
       cohorts_results = Rails.cache.fetch('cohorts', expires_in: 1.day) do

app/controllers/instance_statistics/dev_ops_score_controller.rb

 # frozen_string_literal: true
 
 class InstanceStatistics::DevOpsScoreController < InstanceStatistics::ApplicationController
+  include Analytics::UniqueVisitsHelper
+
+  track_unique_visits :index, target_id: 'i_analytics_dev_ops_score'
+
   # rubocop: disable CodeReuse/ActiveRecord
   def index
     @metric = DevOpsScore::Metric.order(:created_at).last&.present

app/controllers/projects/cycle_analytics_controller.rb

@@ -4,10 +4,13 @@ class Projects::CycleAnalyticsController < Projects::ApplicationController
   include ActionView::Helpers::DateHelper
   include ActionView::Helpers::TextHelper
   include CycleAnalyticsParams
+  include Analytics::UniqueVisitsHelper
 
   before_action :whitelist_query_limiting, only: [:show]
   before_action :authorize_read_cycle_analytics!
 
+  track_unique_visits :show, target_id: 'p_analytics_valuestream'
+
   def show
     @cycle_analytics = ::CycleAnalytics::ProjectLevel.new(@project, options: options(cycle_analytics_project_params))
 

app/controllers/projects/graphs_controller.rb

@@ -2,12 +2,15 @@
 
 class Projects::GraphsController < Projects::ApplicationController
   include ExtractsPath
+  include Analytics::UniqueVisitsHelper
 
   # Authorize
   before_action :require_non_empty_project
   before_action :assign_ref_vars
   before_action :authorize_read_repository_graphs!
 
+  track_unique_visits :charts, target_id: 'p_analytics_repo'
+
   def show
     respond_to do |format|
       format.html

app/controllers/projects/pipelines_controller.rb

@@ -2,6 +2,7 @@
 
 class Projects::PipelinesController < Projects::ApplicationController
   include ::Gitlab::Utils::StrongMemoize
+  include Analytics::UniqueVisitsHelper
 
   before_action :whitelist_query_limiting, only: [:create, :retry]
   before_action :pipeline, except: [:index, :new, :create, :charts]
@@ -20,6 +21,8 @@ class Projects::PipelinesController < Projects::ApplicationController
 
   around_action :allow_gitaly_ref_name_caching, only: [:index, :show]
 
+  track_unique_visits :charts, target_id: 'p_analytics_pipelines'
+
   wrap_parameters Ci::Pipeline
 
   POLLING_INTERVAL = 10_000

app/helpers/analytics/unique_visits_helper.rb

+# frozen_string_literal: true
+
+module Analytics
+  module UniqueVisitsHelper
+    extend ActiveSupport::Concern
+
+    def visitor_id
+      return cookies[:visitor_id] if cookies[:visitor_id].present?
+      return unless current_user
+
+      uuid = SecureRandom.uuid
+      cookies[:visitor_id] = { value: uuid, expires: 24.months }
+      uuid
+    end
+
+    def track_visit(target_id)
+      return unless Feature.enabled?(:track_unique_visits)
+      return unless Gitlab::CurrentSettings.usage_ping_enabled?
+      return unless visitor_id
+
+      Gitlab::Analytics::UniqueVisits.new.track_visit(visitor_id, target_id)
+    end
+
+    class_methods do
+      def track_unique_visits(controller_actions, target_id:)
+        after_action only: controller_actions, if: -> { request.format.html? && request.headers['DNT'] != '1' } do
+          track_visit(target_id)
+        end
+      end
+    end
+  end
+end

changelogs/unreleased/add-unique-vistits-data-to-usage-ping.yml

+---
+title: Add the unique visits data to the usage ping
+merge_request: 33146
+author:
+type: changed

doc/development/telemetry/usage_ping.md

@@ -597,6 +597,21 @@ appear to be associated to any of the services running, since they all appear to
 | `sd`                                                      | `avg_cycle_analytics - production`   |               |                  |         |                                                                            |
 | `missing`                                                 | `avg_cycle_analytics - production`   |               |                  |         |                                                                            |
 | `total`                                                   | `avg_cycle_analytics`                |               |                  |         |                                                                            |
+| `g_analytics_contribution`                                | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /groups/:group/-/contribution_analytics                          |
+| `g_analytics_insights`                                    | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /groups/:group/-/insights                                        |
+| `g_analytics_issues`                                      | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /groups/:group/-/issues_analytics                                |
+| `g_analytics_productivity`                                | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /groups/:group/-/analytics/productivity_analytics                |
+| `g_analytics_valuestream`                                 | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /groups/:group/-/analytics/value_stream_analytics                |
+| `p_analytics_pipelines`                                   | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /:group/:project/pipelines/charts                                |
+| `p_analytics_code_reviews`                                | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /:group/:project/-/analytics/code_reviews                        |
+| `p_analytics_valuestream`                                 | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /:group/:project/-/value_stream_analytics                        |
+| `p_analytics_insights`                                    | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /:group/:project/insights                                        |
+| `p_analytics_issues`                                      | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /:group/:project/-/analytics/issues_analytics                    |
+| `p_analytics_repo`                                        | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /:group/:project/-/graphs/master/charts                          |
+| `u_analytics_todos`                                       | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /dashboard/todos                                                 |
+| `i_analytics_cohorts`                                     | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /-/instance_statistics/cohorts                                   |
+| `i_analytics_dev_ops_score`                               | `analytics_unique_visits`            | `manage`      |                  |         | Visits to /-/instance_statistics/dev_ops_score                             |
+| `analytics_unique_visits_for_any_target`                  | `analytics_unique_visits`            | `manage`      |                  |         | Visits to any of the pages listed above                                    |
 | `clusters_applications_cert_managers`                     | `usage_activity_by_stage`            | `configure`   |                  | CE+EE   | Unique clusters with certificate managers enabled                          |
 | `clusters_applications_helm`                              | `usage_activity_by_stage`            | `configure`   |                  | CE+EE   | Unique clusters with Helm enabled                                          |
 | `clusters_applications_ingress`                           | `usage_activity_by_stage`            | `configure`   |                  | CE+EE   | Unique clusters with Ingress enabled                                       |
@@ -766,6 +781,10 @@ The following is example content of the Usage Ping payload.
     },
     "total": 999
   },
+  "analytics_unique_visits": {
+    "g_analytics_contribution": 999,
+    ...
+  },
   "usage_activity_by_stage": {
     "configure": {
       "project_clusters_enabled": 999,

ee/app/controllers/groups/analytics/cycle_analytics_controller.rb

 # frozen_string_literal: true
 
 class Groups::Analytics::CycleAnalyticsController < Analytics::CycleAnalyticsController
+  include Analytics::UniqueVisitsHelper
+
   layout 'group'
 
   before_action do
     render_403 unless can?(current_user, :read_group_cycle_analytics, @group)
   end
+
+  track_unique_visits :show, target_id: 'g_analytics_valuestream'
 end

ee/app/controllers/groups/analytics/productivity_analytics_controller.rb

@@ -24,6 +24,9 @@ class Groups::Analytics::ProductivityAnalyticsController < Groups::Analytics::Ap
   before_action :validate_params, only: :show, if: -> { request.format.json? }
 
   include IssuableCollections
+  include Analytics::UniqueVisitsHelper
+
+  track_unique_visits :show, target_id: 'g_analytics_productivity'
 
   def show
     respond_to do |format|

ee/app/controllers/groups/contribution_analytics_controller.rb

 # frozen_string_literal: true
 
 class Groups::ContributionAnalyticsController < Groups::ApplicationController
+  include Analytics::UniqueVisitsHelper
+
   before_action :group
   before_action :check_contribution_analytics_available!
   before_action :authorize_read_contribution_analytics!
 
   layout 'group'
 
+  track_unique_visits :show, target_id: 'g_analytics_contribution'
+
   def show
     @start_date = data_collector.from
 

ee/app/controllers/groups/insights_controller.rb

@@ -2,10 +2,13 @@
 
 class Groups::InsightsController < Groups::ApplicationController
   include InsightsActions
+  include Analytics::UniqueVisitsHelper
 
   before_action :authorize_read_group!
   before_action :authorize_read_insights_config_project!
 
+  track_unique_visits :show, target_id: 'g_analytics_insights'
+
   private
 
   def authorize_read_group!

ee/app/controllers/groups/issues_analytics_controller.rb

@@ -2,10 +2,13 @@
 
 class Groups::IssuesAnalyticsController < Groups::ApplicationController
   include IssuableCollections
+  include Analytics::UniqueVisitsHelper
 
   before_action :authorize_read_group!
   before_action :authorize_read_issue_analytics!
 
+  track_unique_visits :show, target_id: 'g_analytics_issues'
+
   def show
     respond_to do |format|
       format.html

ee/app/controllers/projects/analytics/code_reviews_controller.rb

@@ -3,12 +3,16 @@
 module Projects
   module Analytics
     class CodeReviewsController < Projects::ApplicationController
+      include ::Analytics::UniqueVisitsHelper
+
       before_action :authorize_read_code_review_analytics!
       before_action do
         push_frontend_feature_flag(:code_review_analytics_has_new_search)
         push_frontend_feature_flag(:not_issuable_queries, @project, default_enabled: true)
       end
 
+      track_unique_visits :index, target_id: 'p_analytics_code_reviews'
+
       def index
       end
     end

ee/app/controllers/projects/analytics/issues_analytics_controller.rb

@@ -2,9 +2,12 @@
 
 class Projects::Analytics::IssuesAnalyticsController < Projects::ApplicationController
   include IssuableCollections
+  include ::Analytics::UniqueVisitsHelper
 
   before_action :authorize_read_issue_analytics!
 
+  track_unique_visits :show, target_id: 'p_analytics_issues'
+
   def show
     respond_to do |format|
       format.html

ee/app/controllers/projects/insights_controller.rb

@@ -2,11 +2,14 @@
 
 class Projects::InsightsController < Projects::ApplicationController
   include InsightsActions
+  include Analytics::UniqueVisitsHelper
 
   helper_method :project_insights_config
 
   before_action :authorize_read_project!
 
+  track_unique_visits :show, target_id: 'p_analytics_insights'
+
   private
 
   def authorize_read_project!

ee/spec/controllers/groups/analytics/productivity_analytics_controller_spec.rb

@@ -74,6 +74,18 @@ RSpec.describe Groups::Analytics::ProductivityAnalyticsController do
         expect(response).to have_gitlab_http_status(:forbidden)
       end
     end
+
+    context 'when the feature is licensed' do
+      before do
+        stub_licensed_features(productivity_analytics: true)
+        group.add_owner(current_user)
+      end
+
+      it_behaves_like 'tracking unique visits', :show do
+        let(:request_params) { { group_id: group } }
+        let(:target_id) { 'g_analytics_productivity' }
+      end
+    end
   end
 
   describe 'GET show.json' do

ee/spec/controllers/groups/contribution_analytics_controller_spec.rb

@@ -219,10 +219,15 @@ RSpec.describe Groups::ContributionAnalyticsController do
       end
     end
 
-    describe 'GET #index' do
+    describe 'GET #show' do
       subject { get :show, params: { group_id: group.to_param } }
 
       it_behaves_like 'disabled when using an external authorization service'
+
+      it_behaves_like 'tracking unique visits', :show do
+        let(:request_params) { { group_id: group.to_param } }
+        let(:target_id) { 'g_analytics_contribution' }
+      end
     end
   end
 end

ee/spec/controllers/groups/insights_controller_spec.rb

@@ -117,6 +117,13 @@ RSpec.describe Groups::InsightsController do
 
         it_behaves_like '200 status'
       end
+
+      describe 'GET #show' do
+        it_behaves_like 'tracking unique visits', :show do
+          let(:request_params) { params.merge(group_id: parent_group.to_param) }
+          let(:target_id) { 'g_analytics_insights' }
+        end
+      end
     end
 
     context 'when the configuration is attached to a nested group' do

ee/spec/controllers/groups/issues_analytics_controller_spec.rb

@@ -18,4 +18,20 @@ RSpec.describe Groups::IssuesAnalyticsController do
 
     let(:params) { { group_id: group.to_param } }
   end
+
+  describe 'GET #show' do
+    let_it_be(:user) { create(:user) }
+    let_it_be(:group) { create(:group) }
+
+    before do
+      group.add_owner(user)
+      sign_in(user)
+      stub_licensed_features(issues_analytics: true)
+    end
+
+    it_behaves_like 'tracking unique visits', :show do
+      let(:request_params) { { group_id: group.to_param } }
+      let(:target_id) { 'g_analytics_issues' }
+    end
+  end
 end

ee/spec/controllers/projects/analytics/issues_analytics_controller_spec.rb

@@ -16,5 +16,16 @@ RSpec.describe Projects::Analytics::IssuesAnalyticsController do
     end
 
     let(:params) { { namespace_id: group.to_param, project_id: project1.to_param } }
+
+    describe 'GET #show' do
+      before do
+        stub_licensed_features(issues_analytics: true)
+      end
+
+      it_behaves_like 'tracking unique visits', :show do
+        let(:request_params) { { namespace_id: project1.namespace, project_id: project1 } }
+        let(:target_id) { 'p_analytics_issues' }
+      end
+    end
   end
 end

ee/spec/requests/projects/analytics/code_reviews_controller_spec.rb

@@ -50,3 +50,18 @@ RSpec.describe Projects::Analytics::CodeReviewsController, type: :request do
     end
   end
 end
+
+describe Projects::Analytics::CodeReviewsController, type: :controller do
+  let(:user) { create :user }
+  let(:project) { create(:project) }
+
+  before do
+    sign_in user
+    project.add_reporter(user)
+  end
+
+  it_behaves_like 'tracking unique visits', :index do
+    let(:request_params) { { namespace_id: project.namespace, project_id: project } }
+    let(:target_id) { 'p_analytics_code_reviews' }
+  end
+end

lib/gitlab/analytics/unique_visits.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module Analytics
+    class UniqueVisits
+      TARGET_IDS = Set[
+        'g_analytics_contribution',
+        'g_analytics_insights',
+        'g_analytics_issues',
+        'g_analytics_productivity',
+        'g_analytics_valuestream',
+        'p_analytics_pipelines',
+        'p_analytics_code_reviews',
+        'p_analytics_valuestream',
+        'p_analytics_insights',
+        'p_analytics_issues',
+        'p_analytics_repo',
+        'u_analytics_todos',
+        'i_analytics_cohorts',
+        'i_analytics_dev_ops_score'
+      ].freeze
+
+      KEY_EXPIRY_LENGTH = 28.days
+
+      def track_visit(visitor_id, target_id, time = Time.zone.now)
+        target_key = key(target_id, time)
+
+        Gitlab::Redis::SharedState.with do |redis|
+          redis.multi do |multi|
+            multi.pfadd(target_key, visitor_id)
+            multi.expire(target_key, KEY_EXPIRY_LENGTH)
+          end
+        end
+      end
+
+      def weekly_unique_visits_for_target(target_id, week_of: 7.days.ago)
+        Gitlab::Redis::SharedState.with do |redis|
+          redis.pfcount(key(target_id, week_of))
+        end
+      end
+
+      def weekly_unique_visits_for_any_target(week_of: 7.days.ago)
+        keys = TARGET_IDS.map { |target_id| key(target_id, week_of) }
+
+        Gitlab::Redis::SharedState.with do |redis|
+          redis.pfcount(*keys)
+        end
+      end
+
+      private
+
+      def key(target_id, time)
+        raise "Invalid target id #{target_id}" unless TARGET_IDS.include?(target_id.to_s)
+
+        year_week = time.strftime('%G-%V')
+        "#{target_id}-#{year_week}"
+      end
+    end
+  end
+end

lib/gitlab/usage_data.rb

@@ -27,7 +27,7 @@ module Gitlab
       end
 
       def uncached_data
-        clear_memoized_limits
+        clear_memoized
 
         with_finished_at(:recording_ce_finished_at) do
           license_usage_data
@@ -39,6 +39,7 @@ module Gitlab
             .merge(topology_usage_data)
             .merge(usage_activity_by_stage)
             .merge(usage_activity_by_stage(:usage_activity_by_stage_monthly, default_time_period))
+            .merge(analytics_unique_visits_data)
         end
       end
 
@@ -511,8 +512,23 @@ module Gitlab
         {}
       end
 
+      def analytics_unique_visits_data
+        results = ::Gitlab::Analytics::UniqueVisits::TARGET_IDS.each_with_object({}) do |target_id, hash|
+          hash[target_id] = redis_usage_data { unique_visit_service.weekly_unique_visits_for_target(target_id) }
+        end
+        results['analytics_unique_visits_for_any_target'] = redis_usage_data { unique_visit_service.weekly_unique_visits_for_any_target }
+
+        { analytics_unique_visits: results }
+      end
+
       private
 
+      def unique_visit_service
+        strong_memoize(:unique_visit_service) do
+          ::Gitlab::Analytics::UniqueVisits.new
+        end
+      end
+
       def total_alert_issues
         # Remove prometheus table queries once they are deprecated
         # To be removed with https://gitlab.com/gitlab-org/gitlab/-/issues/217407.
@@ -535,9 +551,10 @@ module Gitlab
         end
       end
 
-      def clear_memoized_limits
+      def clear_memoized
         clear_memoization(:user_minimum_id)
         clear_memoization(:user_maximum_id)
+        clear_memoization(:unique_visit_service)
       end
 
       # rubocop: disable CodeReuse/ActiveRecord

spec/controllers/dashboard/todos_controller_spec.rb

@@ -42,6 +42,15 @@ RSpec.describe Dashboard::TodosController do
 
         expect(response).to have_gitlab_http_status(:ok)
       end
+
+      context 'tracking visits' do
+        let_it_be(:authorized_project) { create(:project, :public) }
+
+        it_behaves_like 'tracking unique visits', :index do
+          let(:request_params) { { project_id: authorized_project.id } }
+          let(:target_id) { 'u_analytics_todos' }
+        end
+      end
     end
 
     context "with render_views" do

spec/controllers/instance_statistics/cohorts_controller_spec.rb

@@ -18,4 +18,11 @@ RSpec.describe InstanceStatistics::CohortsController do
 
     expect(response).to have_gitlab_http_status(:not_found)
   end
+
+  describe 'GET #index' do
+    it_behaves_like 'tracking unique visits', :index do
+      let(:request_params) { {} }
+      let(:target_id) { 'i_analytics_cohorts' }
+    end
+  end
 end

spec/controllers/instance_statistics/dev_ops_score_controller_spec.rb

@@ -4,4 +4,17 @@ require 'spec_helper'
 
 RSpec.describe InstanceStatistics::DevOpsScoreController do
   it_behaves_like 'instance statistics availability'
+
+  describe 'GET #index' do
+    let(:user) { create(:user) }
+
+    before do
+      sign_in(user)
+    end
+
+    it_behaves_like 'tracking unique visits', :index do
+      let(:request_params) { {} }
+      let(:target_id) { 'i_analytics_dev_ops_score' }
+    end
+  end
 end

spec/controllers/projects/cycle_analytics_controller_spec.rb

@@ -25,6 +25,13 @@ RSpec.describe Projects::CycleAnalyticsController do
     end
   end
 
+  context 'tracking visits to html page' do
+    it_behaves_like 'tracking unique visits', :show do
+      let(:request_params) { { namespace_id: project.namespace, project_id: project } }
+      let(:target_id) { 'p_analytics_valuestream' }
+    end
+  end
+
   describe 'cycle analytics not set up flag' do
     context 'with no data' do
       it 'is true' do

spec/controllers/projects/graphs_controller_spec.rb

@@ -80,6 +80,15 @@ RSpec.describe Projects::GraphsController do
           expect(assigns[:daily_coverage_options]).to be_nil
         end
       end
+
+      it_behaves_like 'tracking unique visits', :charts do
+        before do
+          sign_in(user)
+        end
+
+        let(:request_params) { { namespace_id: project.namespace.path, project_id: project.path, id: 'master' } }
+        let(:target_id) { 'p_analytics_repo' }
+      end
     end
 
     context 'when languages were previously detected' do

spec/controllers/projects/pipelines_controller_spec.rb

@@ -689,6 +689,15 @@ RSpec.describe Projects::PipelinesController do
     end
   end
 
+  describe 'GET #charts' do
+    let(:pipeline) { create(:ci_pipeline, project: project) }
+
+    it_behaves_like 'tracking unique visits', :charts do
+      let(:request_params) { { namespace_id: project.namespace, project_id: project, id: pipeline.id } }
+      let(:target_id) { 'p_analytics_pipelines' }
+    end
+  end
+
   describe 'POST create' do
     let(:project) { create(:project, :public, :repository) }
 

spec/helpers/analytics/unique_visits_helper_spec.rb

+# frozen_string_literal: true
+
+require "spec_helper"
+
+describe Analytics::UniqueVisitsHelper do
+  include Devise::Test::ControllerHelpers
+
+  describe '#track_visit' do
+    let(:target_id) { 'p_analytics_valuestream' }
+    let(:current_user) { create(:user) }
+
+    before do
+      stub_feature_flags(track_unique_visits: true)
+    end
+
+    it 'does not track visits if feature flag disabled' do
+      stub_feature_flags(track_unique_visits: false)
+      sign_in(current_user)
+
+      expect_any_instance_of(Gitlab::Analytics::UniqueVisits).not_to receive(:track_visit)
+
+      helper.track_visit(target_id)
+    end
+
+    it 'does not track visits if usage ping is disabled' do
+      sign_in(current_user)
+      expect(Gitlab::CurrentSettings).to receive(:usage_ping_enabled?).and_return(false)
+
+      expect_any_instance_of(Gitlab::Analytics::UniqueVisits).not_to receive(:track_visit)
+
+      helper.track_visit(target_id)
+    end
+
+    it 'does not track visit if user is not logged in' do
+      expect_any_instance_of(Gitlab::Analytics::UniqueVisits).not_to receive(:track_visit)
+
+      helper.track_visit(target_id)
+    end
+
+    it 'tracks visit if user is logged in' do
+      sign_in(current_user)
+
+      expect_any_instance_of(Gitlab::Analytics::UniqueVisits).to receive(:track_visit)
+
+      helper.track_visit(target_id)
+    end
+
+    it 'tracks visit if user is not logged in, but has the cookie already' do
+      helper.request.cookies[:visitor_id] = { value: SecureRandom.uuid, expires: 24.months }
+
+      expect_any_instance_of(Gitlab::Analytics::UniqueVisits).to receive(:track_visit)
+
+      helper.track_visit(target_id)
+    end
+  end
+end

spec/lib/gitlab/analytics/unique_visits_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Analytics::UniqueVisits, :clean_gitlab_redis_shared_state do
+  let(:unique_visits) { Gitlab::Analytics::UniqueVisits.new }
+  let(:target1_id) { 'g_analytics_contribution' }
+  let(:target2_id) { 'g_analytics_insights' }
+  let(:target3_id) { 'g_analytics_issues' }
+  let(:visitor1_id) { 'dfb9d2d2-f56c-4c77-8aeb-6cddc4a1f857' }
+  let(:visitor2_id) { '1dd9afb2-a3ee-4de1-8ae3-a405579c8584' }
+
+  describe '#track_visit' do
+    it 'tracks the unique weekly visits for targets' do
+      unique_visits.track_visit(visitor1_id, target1_id, 7.days.ago)
+      unique_visits.track_visit(visitor1_id, target1_id, 7.days.ago)
+      unique_visits.track_visit(visitor2_id, target1_id, 7.days.ago)
+
+      unique_visits.track_visit(visitor2_id, target2_id, 7.days.ago)
+      unique_visits.track_visit(visitor1_id, target2_id, 8.days.ago)
+      unique_visits.track_visit(visitor1_id, target2_id, 15.days.ago)
+
+      expect(unique_visits.weekly_unique_visits_for_target(target1_id)).to eq(2)
+      expect(unique_visits.weekly_unique_visits_for_target(target2_id)).to eq(1)
+
+      expect(unique_visits.weekly_unique_visits_for_target(target2_id, week_of: 15.days.ago)).to eq(1)
+
+      expect(unique_visits.weekly_unique_visits_for_target(target3_id)).to eq(0)
+
+      expect(unique_visits.weekly_unique_visits_for_any_target).to eq(2)
+      expect(unique_visits.weekly_unique_visits_for_any_target(week_of: 15.days.ago)).to eq(1)
+      expect(unique_visits.weekly_unique_visits_for_any_target(week_of: 30.days.ago)).to eq(0)
+    end
+
+    it 'sets the keys in Redis to expire automatically after 28 days' do
+      unique_visits.track_visit(visitor1_id, target1_id)
+
+      Gitlab::Redis::SharedState.with do |redis|
+        redis.scan_each(match: "#{target1_id}-*").each do |key|
+          expect(redis.ttl(key)).to be_within(5.seconds).of(28.days)
+        end
+      end
+    end
+
+    it 'raises an error if an invalid target id is given' do
+      invalid_target_id = "x_invalid"
+
+      expect do
+        unique_visits.track_visit(visitor1_id, invalid_target_id)
+      end.to raise_error("Invalid target id #{invalid_target_id}")
+    end
+  end
+end

spec/lib/gitlab/usage_data_spec.rb

@@ -672,4 +672,36 @@ describe Gitlab::UsageData, :aggregate_failures do
       end
     end
   end
+
+  describe '.analytics_unique_visits_data' do
+    subject { described_class.analytics_unique_visits_data }
+
+    it 'returns the number of unique visits to pages with analytics features' do
+      ::Gitlab::Analytics::UniqueVisits::TARGET_IDS.each do |target_id|
+        expect_any_instance_of(::Gitlab::Analytics::UniqueVisits).to receive(:weekly_unique_visits_for_target).with(target_id).and_return(123)
+      end
+
+      expect_any_instance_of(::Gitlab::Analytics::UniqueVisits).to receive(:weekly_unique_visits_for_any_target).and_return(543)
+
+      expect(subject).to eq({
+        analytics_unique_visits: {
+          'g_analytics_contribution' => 123,
+          'g_analytics_insights' => 123,
+          'g_analytics_issues' => 123,
+          'g_analytics_productivity' => 123,
+          'g_analytics_valuestream' => 123,
+          'p_analytics_pipelines' => 123,
+          'p_analytics_code_reviews' => 123,
+          'p_analytics_valuestream' => 123,
+          'p_analytics_insights' => 123,
+          'p_analytics_issues' => 123,
+          'p_analytics_repo' => 123,
+          'u_analytics_todos' => 123,
+          'i_analytics_cohorts' => 123,
+          'i_analytics_dev_ops_score' => 123,
+          'analytics_unique_visits_for_any_target' => 543
+        }
+      })
+    end
+  end
 end

spec/support/shared_examples/controllers/unique_visits_shared_examples.rb

+# frozen_string_literal: true
+
+RSpec.shared_examples 'tracking unique visits' do |method|
+  it 'tracks unique visit if the format is HTML' do
+    expect_any_instance_of(Gitlab::Analytics::UniqueVisits).to receive(:track_visit).with(instance_of(String), target_id)
+
+    get method, params: request_params, format: :html
+  end
+
+  it 'tracks unique visit if DNT is not enabled' do
+    expect_any_instance_of(Gitlab::Analytics::UniqueVisits).to receive(:track_visit).with(instance_of(String), target_id)
+    request.headers['DNT'] = '0'
+
+    get method, params: request_params, format: :html
+  end
+
+  it 'does not track unique visit if DNT is enabled' do
+    expect_any_instance_of(Gitlab::Analytics::UniqueVisits).not_to receive(:track_visit)
+    request.headers['DNT'] = '1'
+
+    get method, params: request_params, format: :html
+  end
+
+  it 'does not track unique visit if the format is JSON' do
+    expect_any_instance_of(Gitlab::Analytics::UniqueVisits).not_to receive(:track_visit)
+
+    get method, params: request_params, format: :json
+  end
+end