Add the Manage::Import total GMAU metric

Add a total counter of unique users that used any Gitlab Import feature.

changelogs/unreleased/kassio-manage-import-gmau-metrics.yml

+---
+title: Add the Manage::Import total GMAU metric
+merge_request: 51496
+author:
+type: added

lib/gitlab/usage_data.rb

@@ -581,6 +581,7 @@ module Gitlab
           users_created: count(::User.where(time_period), start: user_minimum_id, finish: user_maximum_id),
           omniauth_providers: filtered_omniauth_provider_names.reject { |name| name == 'group_saml' },
           user_auth_by_provider: distinct_count_user_auth_by_provider(time_period),
+          unique_users_all_imports: unique_users_all_imports(time_period),
           bulk_imports: {
             gitlab: distinct_count(::BulkImport.where(time_period, source_type: :gitlab), :user_id)
           },
@@ -898,6 +899,18 @@ module Gitlab
         distinct_count(::Project.imported_from(from).where(time_period).where.not(import_type: nil), :creator_id) # rubocop: disable CodeReuse/ActiveRecord
       end
 
+      # rubocop:disable CodeReuse/ActiveRecord
+      def unique_users_all_imports(time_period)
+        project_imports = distinct_count(::Project.where(time_period).where.not(import_type: nil), :creator_id)
+        bulk_imports = distinct_count(::BulkImport.where(time_period), :user_id)
+        jira_issue_imports = distinct_count(::JiraImportState.where(time_period), :user_id)
+        csv_issue_imports = distinct_count(Issues::CsvImport.where(time_period), :user_id)
+        group_imports = distinct_count(::GroupImportState.where(time_period), :user_id)
+
+        project_imports + bulk_imports + jira_issue_imports + csv_issue_imports + group_imports
+      end
+      # rubocop:enable CodeReuse/ActiveRecord
+
       # rubocop:disable CodeReuse/ActiveRecord
       def distinct_count_user_auth_by_provider(time_period)
         counts = auth_providers_except_ldap.each_with_object({}) do |provider, hash|

spec/lib/gitlab/usage_data_spec.rb

@@ -228,6 +228,29 @@ RSpec.describe Gitlab::UsageData, :aggregate_failures do
       )
     end
 
+    it 'includes import gmau usage data' do
+      for_defined_days_back do
+        user = create(:user)
+        group = create(:group)
+
+        group.add_owner(user)
+
+        create(:project, import_type: :github, creator_id: user.id)
+        create(:jira_import_state, :finished, project: create(:project, creator_id: user.id))
+        create(:issue_csv_import, user: user)
+        create(:group_import_state, group: group, user: user)
+        create(:bulk_import, user: user)
+      end
+
+      expect(described_class.usage_activity_by_stage_manage({})).to include(
+        unique_users_all_imports: 10
+      )
+
+      expect(described_class.usage_activity_by_stage_manage(described_class.last_28_days_time_period)).to include(
+        unique_users_all_imports: 5
+      )
+    end
+
     it 'includes imports usage data' do
       for_defined_days_back do
         user = create(:user)