Add protected_branches_except_default to usage ping

Adds a new key to the usage ping that counts
the number of protected branches used in an
instance excluding branches named main, master
or the default for the instance.

changelogs/unreleased/233758-protected-branches-usage-ping.yml

+---
+title: Add protected branches count to usage ping
+merge_request: 38797
+author:
+type: added

doc/development/telemetry/event_dictionary.md

@@ -96,6 +96,7 @@ An event dictionary is a single source of truth that outlines what events and pr
 | `projects_with_repositories_enabled`                      | `counts`                             |               |                  |         |                                                                            |
 | `projects_with_error_tracking_enabled`                    | `counts`                             | `monitor`     |                  |         |                                                                            |
 | `protected_branches`                                      | `counts`                             |               |                  |         |                                                                            |
+| `protected_branches_except_default`                       | `counts`                             |               |                  |  CE+EE  | All protected branches except `main`, `master` or the default              |
 | `releases`                                                | `counts`                             | `release`     |                  |         | Unique release tags                                                        |
 | `remote_mirrors`                                          | `counts`                             |               |                  |         |                                                                            |
 | `requirements_created`                                    | `counts`                             |               |                  |         |                                                                            |

lib/gitlab/usage_data.rb

@@ -140,6 +140,7 @@ module Gitlab
             projects_with_terraform_reports: distinct_count(::Ci::JobArtifact.terraform_reports, :project_id),
             projects_with_terraform_states: distinct_count(::Terraform::State, :project_id),
             protected_branches: count(ProtectedBranch),
+            protected_branches_except_default: count(ProtectedBranch.where.not(name: ['main', 'master', Gitlab::CurrentSettings.default_branch_name])),
             releases: count(Release),
             remote_mirrors: count(RemoteMirror),
             personal_snippets: count(PersonalSnippet),

spec/factories/usage_data.rb

@@ -47,6 +47,8 @@ FactoryBot.define do
       create(:zoom_meeting, project: projects[0], issue: projects[0].issues[2], issue_status: :added)
       create_list(:zoom_meeting, 2, project: projects[0], issue: projects[0].issues[2], issue_status: :removed)
       create(:sentry_issue, issue: projects[0].issues[0])
+      create(:protected_branch, project: projects[0])
+      create(:protected_branch, name: 'main', project: projects[0])
 
       # Incident Labeled Issues
       incident_label_attrs = IncidentManagement::CreateIncidentLabelService::LABEL_PROPERTIES

spec/lib/gitlab/usage_data_spec.rb

@@ -354,6 +354,8 @@ RSpec.describe Gitlab::UsageData, :aggregate_failures do
       expect(count_data[:projects_with_prometheus_alerts]).to eq(2)
       expect(count_data[:projects_with_terraform_reports]).to eq(2)
       expect(count_data[:projects_with_terraform_states]).to eq(2)
+      expect(count_data[:protected_branches]).to eq(2)
+      expect(count_data[:protected_branches_except_default]).to eq(1)
       expect(count_data[:terraform_reports]).to eq(6)
       expect(count_data[:terraform_states]).to eq(3)
       expect(count_data[:issues_created_from_gitlab_error_tracking_ui]).to eq(1)

spec/support/helpers/usage_data_helpers.rb

@@ -119,6 +119,7 @@ module UsageDataHelpers
       projects_with_terraform_states
       pages_domains
       protected_branches
+      protected_branches_except_default
       releases
       remote_mirrors
       snippets