1 files changed, 121 insertions, 0 deletions
diff --git a/spec/workers/database/batched_background_migration_worker_spec.rb b/spec/workers/database/batched_background_migration_worker_spec.rb
new file mode 100644
index 00000000000..b13d1f5c7aa
--- /dev/null
+++ b/spec/workers/database/batched_background_migration_worker_spec.rb
@@ -0,0 +1,121 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Database::BatchedBackgroundMigrationWorker, '#perform', :clean_gitlab_redis_shared_state do
+  include ExclusiveLeaseHelpers
+
+  let(:worker) { described_class.new }
+
+  context 'when the feature flag is disabled' do
+    before do
+      stub_feature_flags(execute_batched_migrations_on_schedule: false)
+    end
+
+    it 'does nothing' do
+      expect(worker).not_to receive(:active_migration)
+      expect(worker).not_to receive(:run_active_migration)
+
+      worker.perform
+    end
+  end
+
+  context 'when the feature flag is enabled' do
+    before do
+      stub_feature_flags(execute_batched_migrations_on_schedule: true)
+
+      allow(Gitlab::Database::BackgroundMigration::BatchedMigration).to receive(:active_migration).and_return(nil)
+    end
+
+    context 'when no active migrations exist' do
+      it 'does nothing' do
+        expect(worker).not_to receive(:run_active_migration)
+
+        worker.perform
+      end
+    end
+
+    context 'when active migrations exist' do
+      let(:job_interval) { 5.minutes }
+      let(:lease_timeout) { 15.minutes }
+      let(:lease_key) { 'batched_background_migration_worker' }
+      let(:migration) { build(:batched_background_migration, :active, interval: job_interval) }
+      let(:interval_variance) { described_class::INTERVAL_VARIANCE }
+
+      before do
+        allow(Gitlab::Database::BackgroundMigration::BatchedMigration).to receive(:active_migration)
+          .and_return(migration)
+
+        allow(migration).to receive(:interval_elapsed?).with(variance: interval_variance).and_return(true)
+        allow(migration).to receive(:reload)
+      end
+
+      context 'when the reloaded migration is no longer active' do
+        it 'does not run the migration' do
+          expect_to_obtain_exclusive_lease(lease_key, timeout: lease_timeout)
+
+          expect(migration).to receive(:reload)
+          expect(migration).to receive(:active?).and_return(false)
+
+          expect(worker).not_to receive(:run_active_migration)
+
+          worker.perform
+        end
+      end
+
+      context 'when the interval has not elapsed' do
+        it 'does not run the migration' do
+          expect_to_obtain_exclusive_lease(lease_key, timeout: lease_timeout)
+
+          expect(migration).to receive(:interval_elapsed?).with(variance: interval_variance).and_return(false)
+
+          expect(worker).not_to receive(:run_active_migration)
+
+          worker.perform
+        end
+      end
+
+      context 'when the reloaded migration is still active and the interval has elapsed' do
+        it 'runs the migration' do
+          expect_to_obtain_exclusive_lease(lease_key, timeout: lease_timeout)
+
+          expect_next_instance_of(Gitlab::Database::BackgroundMigration::BatchedMigrationRunner) do |instance|
+            expect(instance).to receive(:run_migration_job).with(migration)
+          end
+
+          expect(worker).to receive(:run_active_migration).and_call_original
+
+          worker.perform
+        end
+      end
+
+      context 'when the calculated timeout is less than the minimum allowed' do
+        let(:minimum_timeout) { described_class::MINIMUM_LEASE_TIMEOUT }
+        let(:job_interval) { 2.minutes }
+
+        it 'sets the lease timeout to the minimum value' do
+          expect_to_obtain_exclusive_lease(lease_key, timeout: minimum_timeout)
+
+          expect_next_instance_of(Gitlab::Database::BackgroundMigration::BatchedMigrationRunner) do |instance|
+            expect(instance).to receive(:run_migration_job).with(migration)
+          end
+
+          expect(worker).to receive(:run_active_migration).and_call_original
+
+          worker.perform
+        end
+      end
+
+      it 'always cleans up the exclusive lease' do
+        lease = stub_exclusive_lease_taken(lease_key, timeout: lease_timeout)
+
+        expect(lease).to receive(:try_obtain).and_return(true)
+
+        expect(worker).to receive(:run_active_migration).and_raise(RuntimeError, 'I broke')
+        expect(lease).to receive(:cancel)
+
+        expect { worker.perform }.to raise_error(RuntimeError, 'I broke')
+      end
+    end
+  end
+end