Track users updating work item titles

Implement service ping for event users_updating_work_item_title

app/services/system_notes/issuables_service.rb

@@ -160,6 +160,7 @@ module SystemNotes
       body = "changed title from **#{marked_old_title}** to **#{marked_new_title}**"
 
       issue_activity_counter.track_issue_title_changed_action(author: author) if noteable.is_a?(Issue)
+      work_item_activity_counter.track_work_item_title_changed_action(author: author) if noteable.is_a?(WorkItem)
 
       create_note(NoteSummary.new(noteable, project, author, body, action: 'title'))
     end
@@ -484,6 +485,10 @@ module SystemNotes
       Gitlab::UsageDataCounters::IssueActivityUniqueCounter
     end
 
+    def work_item_activity_counter
+      Gitlab::UsageDataCounters::WorkItemActivityUniqueCounter
+    end
+
     def track_cross_reference_action
       issue_activity_counter.track_issue_cross_referenced_action(author: author) if noteable.is_a?(Issue)
     end

config/feature_flags/development/track_work_items_activity.yml

+---
+name: track_work_items_activity
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/80532
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/352903
+milestone: '14.9'
+type: development
+group: group::project management
+default_enabled: false

config/metrics/counts_28d/20220214202927_users_updating_work_item_title.yml

+---
+key_path: redis_hll_counters.work_items.users_updating_work_item_title_monthly
+description: Unique users updating a work item's title
+product_category: team planning
+product_section: dev
+product_stage: plan
+product_group: group::project management
+value_type: number
+status: active
+milestone: '14.9'
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/80532
+time_frame: 28d
+data_source: redis_hll
+data_category: optional
+instrumentation_class: RedisHLLMetric
+options:
+  events:
+    - users_updating_work_item_title
+distribution:
+- ce
+- ee
+tier:
+- free
+- premium
+- ultimate

config/metrics/counts_7d/20220216204730_users_updating_work_item_title_weekly.yml

+---
+key_path: redis_hll_counters.work_items.users_updating_work_item_title_weekly
+description: Unique users updating a work item's title
+product_category: team planning
+product_section: dev
+product_stage: plan
+product_group: group::project management
+value_type: number
+status: active
+milestone: '14.9'
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/80532
+time_frame: 7d
+data_source: redis_hll
+data_category: optional
+instrumentation_class: RedisHLLMetric
+options:
+  events:
+    - users_updating_work_item_title
+distribution:
+- ce
+- ee
+tier:
+- free
+- premium
+- ultimate

lib/gitlab/usage_data_counters/known_events/work_items.yml

+---
+- name: users_updating_work_item_title
+  category: work_items
+  redis_slot: users
+  aggregation: weekly
+  feature_flag: track_work_items_activity

lib/gitlab/usage_data_counters/work_item_activity_unique_counter.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module UsageDataCounters
+    module WorkItemActivityUniqueCounter
+      WORK_ITEM_TITLE_CHANGED = 'users_updating_work_item_title'
+
+      class << self
+        def track_work_item_title_changed_action(author:)
+          track_unique_action(WORK_ITEM_TITLE_CHANGED, author)
+        end
+
+        private
+
+        def track_unique_action(action, author)
+          return unless author
+
+          Gitlab::UsageDataCounters::HLLRedisCounter.track_event(action, values: author.id)
+        end
+      end
+    end
+  end
+end

spec/lib/gitlab/usage_data_counters/hll_redis_counter_spec.rb

@@ -50,7 +50,8 @@ RSpec.describe Gitlab::UsageDataCounters::HLLRedisCounter, :clean_gitlab_redis_s
         'importer',
         'network_policies',
         'geo',
-        'growth'
+        'growth',
+        'work_items'
       )
     end
   end

spec/lib/gitlab/usage_data_counters/work_item_activity_unique_counter_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::UsageDataCounters::WorkItemActivityUniqueCounter, :clean_gitlab_redis_shared_state do
+  let(:user) { build(:user, id: 1) }
+
+  shared_examples 'counter that does not track the event' do
+    it 'does not track the event' do
+      expect { 3.times { track_event } }.to not_change {
+        Gitlab::UsageDataCounters::HLLRedisCounter.unique_events(
+          event_names: event_name,
+          start_date: 2.weeks.ago,
+          end_date: 2.weeks.from_now
+        )
+      }
+    end
+  end
+
+  describe '.track_work_item_title_changed_action' do
+    subject(:track_event) { described_class.track_work_item_title_changed_action(author: user) }
+
+    let(:event_name) { described_class::WORK_ITEM_TITLE_CHANGED }
+
+    context 'when track_work_items_activity FF is enabled' do
+      it 'tracks a unique event only once' do
+        expect { 3.times { track_event } }.to change {
+          Gitlab::UsageDataCounters::HLLRedisCounter.unique_events(
+            event_names: described_class::WORK_ITEM_TITLE_CHANGED,
+            start_date: 2.weeks.ago,
+            end_date: 2.weeks.from_now
+          )
+        }.by(1)
+      end
+
+      context 'when author is nil' do
+        let(:user) { nil }
+
+        it_behaves_like 'counter that does not track the event'
+      end
+    end
+
+    context 'when track_work_items_activity FF is disabled' do
+      before do
+        stub_feature_flags(track_work_items_activity: false)
+      end
+
+      it_behaves_like 'counter that does not track the event'
+    end
+  end
+end

spec/services/work_items/update_service_spec.rb

@@ -23,6 +23,9 @@ RSpec.describe WorkItems::UpdateService do
 
       it 'triggers issuable_title_updated graphql subscription' do
         expect(GraphqlTriggers).to receive(:issuable_title_updated).with(work_item).and_call_original
+        expect(Gitlab::UsageDataCounters::WorkItemActivityUniqueCounter).to receive(:track_work_item_title_changed_action).with(author: current_user)
+        # During the work item transition we also want to track work items as issues
+        expect(Gitlab::UsageDataCounters::IssueActivityUniqueCounter).to receive(:track_issue_title_changed_action)
 
         update_work_item
       end
@@ -33,6 +36,7 @@ RSpec.describe WorkItems::UpdateService do
 
       it 'does not trigger issuable_title_updated graphql subscription' do
         expect(GraphqlTriggers).not_to receive(:issuable_title_updated)
+        expect(Gitlab::UsageDataCounters::WorkItemActivityUniqueCounter).not_to receive(:track_work_item_title_changed_action)
 
         update_work_item
       end