Find or initialize instance-level services

This is similar to the service templates feature that we are going to
remove: https://gitlab.com/groups/gitlab-org/-/epics/2430 but we don't
need to create the services in the database at this point.

https://gitlab.com/gitlab-org/gitlab/-/merge_requests/25752 implemented
the frontend changes under a feature flag, this implements the backend
changes.

This also disables instance_level_integrations feature flag in the
tests.

app/controllers/admin/application_settings_controller.rb

@@ -8,7 +8,7 @@ class Admin::ApplicationSettingsController < Admin::ApplicationController
   # ApplicationSetting model uses Gitlab::ThreadMemoryCache for caching and the
   # cache might be stale immediately after an update.
   # https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/30233
-  before_action :set_application_setting
+  before_action :set_application_setting, except: :integrations
 
   before_action :whitelist_query_limiting, only: [:usage_data]
 
@@ -29,12 +29,11 @@ class Admin::ApplicationSettingsController < Admin::ApplicationController
 
   def integrations
     if Feature.enabled?(:instance_level_integrations)
-      # TODO: Update this with actual integrations
-      # To be fixed with https://gitlab.com/gitlab-org/gitlab/-/issues/199388
-      @integrations = []
+      @integrations = Service.find_or_initialize_instances.sort_by(&:title)
+    else
+      set_application_setting
+      perform_update if submitted?
     end
-
-    perform_update if submitted?
   end
 
   def update

app/controllers/admin/services_controller.rb

@@ -6,7 +6,7 @@ class Admin::ServicesController < Admin::ApplicationController
   before_action :service, only: [:edit, :update]
 
   def index
-    @services = Service.find_or_create_templates
+    @services = Service.find_or_create_templates.sort_by(&:title)
   end
 
   def edit

app/models/service.rb

@@ -47,6 +47,7 @@ class Service < ApplicationRecord
   scope :without_defaults, -> { where(default: false) }
   scope :by_type, -> (type) { where(type: type) }
   scope :templates, -> { where(template: true, type: available_services_types) }
+  scope :instances, -> { where(instance: true, type: available_services_types) }
 
   scope :push_hooks, -> { where(push_events: true, active: true) }
   scope :tag_push_hooks, -> { where(tag_push_events: true, active: true) }
@@ -260,17 +261,16 @@ class Service < ApplicationRecord
     self.category == :issue_tracker
   end
 
-  # Find all service templates; if some of them do not exist, create them
-  # within a transaction to perform the lowest possible SQL queries.
   def self.find_or_create_templates
     create_nonexistent_templates
     templates
   end
 
   private_class_method def self.create_nonexistent_templates
-    nonexistent_services = available_services_types - templates.map(&:type)
+    nonexistent_services = list_nonexistent_services_for(templates)
     return if nonexistent_services.empty?
 
+    # Create within a transaction to perform the lowest possible SQL queries.
     transaction do
       nonexistent_services.each do |service_type|
         service_type.constantize.create(template: true)
@@ -278,6 +278,20 @@ class Service < ApplicationRecord
     end
   end
 
+  def self.find_or_initialize_instances
+    instances + build_nonexistent_instances
+  end
+
+  private_class_method def self.build_nonexistent_instances
+    list_nonexistent_services_for(instances).map do |service_type|
+      service_type.constantize.new
+    end
+  end
+
+  private_class_method def self.list_nonexistent_services_for(scope)
+    available_services_types - scope.map(&:type)
+  end
+
   def self.available_services_names
     service_names = %w[
       alerts

app/views/admin/services/index.html.haml

@@ -10,7 +10,7 @@
         %th Service
         %th Description
         %th Last edit
-    - @services.sort_by(&:title).each do |service|
+    - @services.each do |service|
       %tr
         %td
           = boolean_to_icon service.activated?

app/views/projects/services/_integrations.html.haml

@@ -12,7 +12,7 @@
       %th{ role: 'columnheader', scope: 'col', 'aria-colindex': 4 }= _('Last updated')
 
   %tbody{ role: 'rowgroup' }
-    - @integrations&.each do |integration|
+    - @integrations.each do |integration|
       %tr{ role: 'row' }
         %td{ role: 'cell', 'aria-colindex': 1 }
           = boolean_to_icon integration.activated?

ee/spec/features/admin/admin_settings_spec.rb

@@ -6,6 +6,7 @@ describe 'Admin updates EE-only settings' do
   include StubENV
 
   before do
+    stub_feature_flags(instance_level_integrations: false)
     stub_env('IN_MEMORY_APPLICATION_SETTINGS', 'false')
     sign_in(create(:admin))
     allow(License).to receive(:feature_available?).and_return(true)
@@ -57,7 +58,7 @@ describe 'Admin updates EE-only settings' do
 
   context 'Elasticsearch settings' do
     before do
-      visit general_admin_application_settings_path
+      visit integrations_admin_application_settings_path
       page.within('.as-elasticsearch') do
         click_button 'Expand'
       end
@@ -137,7 +138,7 @@ describe 'Admin updates EE-only settings' do
       namespace = create(:elasticsearch_indexed_namespace).namespace
       project = create(:elasticsearch_indexed_project).project
 
-      visit general_admin_application_settings_path
+      visit integrations_admin_application_settings_path
 
       expect(ElasticsearchIndexedNamespace.count).to be > 0
       expect(ElasticsearchIndexedProject.count).to be > 0
@@ -167,7 +168,7 @@ describe 'Admin updates EE-only settings' do
 
   it 'Enable Slack application' do
     allow(Gitlab).to receive(:com?).and_return(true)
-    visit general_admin_application_settings_path
+    visit integrations_admin_application_settings_path
 
     page.within('.as-slack') do
       check 'Enable Slack application'

spec/controllers/admin/application_settings_controller_spec.rb

@@ -127,6 +127,10 @@ describe Admin::ApplicationSettingsController do
     end
 
     describe 'verify panel actions' do
+      before do
+        stub_feature_flags(instance_level_integrations: false)
+      end
+
       Admin::ApplicationSettingsController::VALID_SETTING_PANELS.each do |valid_action|
         it_behaves_like 'renders correct panels' do
           let(:action) { valid_action }

spec/features/admin/admin_settings_spec.rb

@@ -194,6 +194,13 @@ describe 'Admin updates settings', :clean_gitlab_redis_shared_state, :do_not_moc
         expect(page).to have_content "Application settings saved successfully"
         expect(current_settings.terminal_max_session_time).to eq(15)
       end
+    end
+
+    context 'Integrations page' do
+      before do
+        stub_feature_flags(instance_level_integrations: false)
+        visit integrations_admin_application_settings_path
+      end
 
       it 'Enable hiding third party offers' do
         page.within('.as-third-party-offers') do

spec/features/projects/clusters/gcp_spec.rb

@@ -205,10 +205,11 @@ describe 'Gcp Cluster', :js, :do_not_mock_admin_mode do
     let(:admin) { create(:admin) }
 
     before do
+      stub_feature_flags(instance_level_integrations: false)
       stub_env('IN_MEMORY_APPLICATION_SETTINGS', 'false')
       sign_in(admin)
       gitlab_enable_admin_mode_sign_in(admin)
-      visit general_admin_application_settings_path
+      visit integrations_admin_application_settings_path
     end
 
     it 'user does not see the offer' do

spec/models/service_spec.rb

@@ -149,6 +149,47 @@ describe Service do
     end
   end
 
+  describe '.find_or_initialize_instances' do
+    shared_examples 'service instances' do
+      it 'returns the available service instances' do
+        expect(Service.find_or_initialize_instances.pluck(:type)).to match_array(Service.available_services_types)
+      end
+
+      it 'does not create service instances' do
+        expect { Service.find_or_initialize_instances }.not_to change { Service.count }
+      end
+    end
+
+    it_behaves_like 'service instances'
+
+    context 'with all existing instances' do
+      before do
+        Service.insert_all(
+          Service.available_services_types.map { |type| { instance: true, type: type } }
+        )
+      end
+
+      it_behaves_like 'service instances'
+
+      context 'with a previous existing service (Previous) and a new service (Asana)' do
+        before do
+          Service.insert(type: 'PreviousService', instance: true)
+          Service.delete_by(type: 'AsanaService', instance: true)
+        end
+
+        it_behaves_like 'service instances'
+      end
+    end
+
+    context 'with a few existing instances' do
+      before do
+        create(:jira_service, :instance)
+      end
+
+      it_behaves_like 'service instances'
+    end
+  end
+
   describe 'template' do
     let(:project) { create(:project) }
 
@@ -173,7 +214,7 @@ describe Service do
         end
 
         it 'does not create service templates' do
-          expect { Service.find_or_create_templates }.to change { Service.count }.by(0)
+          expect { Service.find_or_create_templates }.not_to change { Service.count }
         end
 
         it_behaves_like 'retrieves service templates'