Migration for deleting service template records

Added the post deploy migration for deleting
service template records from the database

Changelog: other

db/post_migrate/20220202105733_delete_service_template_records.rb

+# frozen_string_literal: true
+
+class DeleteServiceTemplateRecords < Gitlab::Database::Migration[1.0]
+  class Integration < ActiveRecord::Base
+    # Disable single-table inheritance
+    self.inheritance_column = :_type_disabled
+  end
+  def up
+    Integration.where(template: true).delete_all
+  end
+
+  def down
+    # no-op
+  end
+end

db/schema_migrations/20220202105733

+6f2919091a6998f2f18f8dbff3c968e68dc218ab0e51341164d1fc5b8abf72ae
\ No newline at end of file

spec/migrations/20220202105733_delete_service_template_records_spec.rb

+# frozen_string_literal: true
+require 'spec_helper'
+
+require_migration!
+
+RSpec.describe DeleteServiceTemplateRecords do
+  let(:integrations) { table(:integrations) }
+  let(:chat_names) { table(:chat_names) }
+  let(:web_hooks) { table(:web_hooks) }
+  let(:slack_integrations) { table(:slack_integrations) }
+  let(:zentao_tracker_data) { table(:zentao_tracker_data) }
+  let(:jira_tracker_data) { table(:jira_tracker_data) }
+  let(:issue_tracker_data) { table(:issue_tracker_data) }
+
+  before do
+    template = integrations.create!(template: true)
+    chat_names.create!(service_id: template.id, user_id: 1, team_id: 1, chat_id: 1)
+    web_hooks.create!(service_id: template.id)
+    slack_integrations.create!(service_id: template.id, team_id: 1, team_name: 'team', alias: 'alias', user_id: 1)
+    zentao_tracker_data.create!(integration_id: template.id)
+    jira_tracker_data.create!(service_id: template.id)
+    issue_tracker_data.create!(service_id: template.id)
+
+    integrations.create!(template: false)
+  end
+
+  it 'deletes template records and associated data' do
+    expect { migrate! }
+      .to change { integrations.where(template: true).count }.from(1).to(0)
+      .and change { chat_names.count }.from(1).to(0)
+      .and change { web_hooks.count }.from(1).to(0)
+      .and change { slack_integrations.count }.from(1).to(0)
+      .and change { zentao_tracker_data.count }.from(1).to(0)
+      .and change { jira_tracker_data.count }.from(1).to(0)
+      .and change { issue_tracker_data.count }.from(1).to(0)
+  end
+
+  it 'does not delete non template records' do
+    expect { migrate! }
+      .not_to change { integrations.where(template: false).count }
+  end
+end