Ensure newly paid groups are indexed in Elasticsearch

Create a new ElasticsearchIndexedNamespace object
when GitlabSubscription objects are created/updated
to paid, hosted plans. Trials are not included but
will be indexed if updated to a non-trial paid plan.

doc/development/integrations/elasticsearch_for_paid_tiers_on_gitlabcom.md

+# Elasticsearch for paid tiers on GitLab.com
+
+> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/220246) in GitLab 13.2
+> - It's deployed behind a feature flag, disabled by default.
+> - It's disabled on GitLab.com.
+> - It's not recommended for use in GitLab self-managed instances.
+
+This document describes how to enable Elasticsearch with GitLab for all paid tiers on GitLab.com. Once enabled,
+all paid tiers will have access to the [Advanced Global Search feature](../../integration/elasticsearch.md) on GitLab.com.
+
+## Enable or disable Elasticsearch for all paid tiers on GitLab.com
+
+Since we're still in the process of rolling this out and want to control the timing this is behind a feature flag
+which defaults to off.
+
+To enable it:
+
+```ruby
+# Instance-wide
+Feature.enable(:elasticsearch_index_only_paid_groups)
+```
+
+To disable it:
+
+```ruby
+# Instance-wide
+Feature.disable(:elasticsearch_index_only_paid_groups)
+```

ee/app/models/gitlab_subscription.rb

@@ -3,6 +3,7 @@
 class GitlabSubscription < ApplicationRecord
   default_value_for(:start_date) { Date.today }
   before_update :log_previous_state_for_update
+  after_commit :index_namespace, on: [:create, :update]
   after_destroy_commit :log_previous_state_for_destroy
 
   belongs_to :namespace
@@ -86,4 +87,15 @@ class GitlabSubscription < ApplicationRecord
   def hosted?
     namespace_id.present?
   end
+
+  # Kick off Elasticsearch indexing for paid groups with new or upgraded paid, hosted subscriptions
+  # Uses safe_find_or_create_by to avoid ActiveRecord::RecordNotUnique exception when upgrading from
+  # one paid plan to another paid plan
+  def index_namespace
+    return unless ::Feature.enabled?(:elasticsearch_index_only_paid_groups) &&
+        has_a_paid_hosted_plan? &&
+        saved_changes.key?('hosted_plan_id')
+
+    ElasticsearchIndexedNamespace.safe_find_or_create_by!(namespace_id: namespace_id)
+  end
 end

ee/changelogs/unreleased/220246-need-a-way-to-ensure-all-newly-created-paid-groups-are-indexed.yml

+---
+title: Ensure all newly paid groups are indexed.
+merge_request: 35172
+author:
+type: changed

ee/spec/factories/gitlab_subscriptions.rb

@@ -28,5 +28,17 @@ FactoryBot.define do
     trait :gold do
       association :hosted_plan, factory: :gold_plan
     end
+
+    # for testing elasticsearch_indexed_namespace and elastic_namespace_rollout_worker which
+    # eventually will not be required once all paid groups are indexed
+    trait :without_index_namespace_callback do
+      after(:build) do |gitlab_subcription|
+        GitlabSubscription.skip_callback(:commit, :after, :index_namespace)
+      end
+
+      after(:create) do
+        GitlabSubscription.set_callback(:commit, :after, :index_namespace)
+      end
+    end
   end
 end

ee/spec/models/elasticsearch_indexed_namespace_spec.rb

@@ -35,9 +35,9 @@ RSpec.describe ElasticsearchIndexedNamespace do
     end
 
     let_it_be(:namespaces) { create_list(:namespace, 3) }
-    let_it_be(:subscription1) { create(:gitlab_subscription, namespace: namespaces[2]) }
-    let_it_be(:subscription2) { create(:gitlab_subscription, namespace: namespaces[0]) }
-    let_it_be(:subscription3) { create(:gitlab_subscription, :silver, namespace: namespaces[1]) }
+    let_it_be(:subscription1) { create(:gitlab_subscription, :without_index_namespace_callback, namespace: namespaces[2]) }
+    let_it_be(:subscription2) { create(:gitlab_subscription, :without_index_namespace_callback, namespace: namespaces[0]) }
+    let_it_be(:subscription3) { create(:gitlab_subscription, :silver, :without_index_namespace_callback, namespace: namespaces[1]) }
 
     before do
       stub_ee_application_setting(elasticsearch_indexing: false)

ee/spec/models/gitlab_subscription_spec.rb

@@ -3,6 +3,12 @@
 require 'spec_helper'
 
 RSpec.describe GitlabSubscription do
+  using RSpec::Parameterized::TableSyntax
+
+  before do
+    stub_feature_flags(elasticsearch_index_only_paid_groups: false)
+  end
+
   %i[free_plan bronze_plan silver_plan gold_plan early_adopter_plan].each do |plan|
     let_it_be(plan) { create(plan) }
   end
@@ -247,6 +253,44 @@ RSpec.describe GitlabSubscription do
   end
 
   describe 'callbacks' do
+    context 'after_commit :index_namespace' do
+      where(:elasticsearch_index_only_paid_groups_setting, :operation, :initial_plan, :should_update_plan?, :should_index_namespace?) do
+        false   | :create   | :bronze         | false   | false
+        true    | :create   | :bronze         | false   | true
+        true    | :create   | :free           | false   | false
+        true    | :create   | { trial: true } | false   | false
+        false   | :update   | :bronze         | false   | false
+        true    | :update   | :bronze         | false   | false
+        true    | :update   | :bronze         | true    | true
+        true    | :update   | :free           | true    | true
+        true    | :update   | { trial: true } | true    | true
+      end
+
+      with_them do
+        let!(:gitlab_subscription) { operation == :create ? build(:gitlab_subscription, initial_plan) : create(:gitlab_subscription, initial_plan) }
+
+        before do
+          stub_feature_flags(elasticsearch_index_only_paid_groups: elasticsearch_index_only_paid_groups_setting)
+        end
+
+        it 'indexes namespace' do
+          if should_index_namespace?
+            expect(ElasticsearchIndexedNamespace).to receive(:safe_find_or_create_by!).with(namespace_id: gitlab_subscription.namespace_id)
+          else
+            expect(ElasticsearchIndexedNamespace).not_to receive(:safe_find_or_create_by!)
+          end
+
+          case operation
+          when :create
+            gitlab_subscription.save!
+          when :update
+            update_attributes = should_update_plan? ? { hosted_plan: create(:silver_plan), trial: false } : { max_seats_used: 32 }
+            gitlab_subscription.update!(update_attributes)
+          end
+        end
+      end
+    end
+
     it 'gitlab_subscription columns are contained in gitlab_subscription_history columns' do
       diff_attrs = %w(updated_at)
       expect(described_class.attribute_names - GitlabSubscriptionHistory.attribute_names).to eq(diff_attrs)

ee/spec/workers/elastic_namespace_rollout_worker_spec.rb

@@ -15,7 +15,7 @@ RSpec.describe ElasticNamespaceRolloutWorker do
 
   before_all do
     Plan::PAID_HOSTED_PLANS.each do |plan|
-      create_list(:gitlab_subscription, 4, hosted_plan: public_send("#{plan}_plan"))
+      create_list(:gitlab_subscription, 4, :without_index_namespace_callback, hosted_plan: public_send("#{plan}_plan"))
     end
   end