Move pipeline retry to worker

Makes the Projects::PipelinesController#retry endpoint perform the retry
asynchronously via a worker.

Changelog: changed

app/controllers/projects/pipelines_controller.rb

@@ -176,7 +176,11 @@ class Projects::PipelinesController < Projects::ApplicationController
   end
 
   def retry
-    pipeline.retry_failed(current_user)
+    if Feature.enabled?(:background_pipeline_retry_endpoint, @project)
+      ::Ci::RetryPipelineWorker.perform_async(pipeline.id, current_user.id) # rubocop:disable CodeReuse/Worker
+    else
+      pipeline.retry_failed(current_user)
+    end
 
     respond_to do |format|
       format.html do

app/workers/all_queues.yml

@@ -1515,6 +1515,15 @@
   :weight: 3
   :idempotent:
   :tags: []
+- :name: pipeline_default:ci_retry_pipeline
+  :worker_name: Ci::RetryPipelineWorker
+  :feature_category: :continuous_integration
+  :has_external_dependencies:
+  :urgency: :high
+  :resource_boundary: :cpu
+  :weight: 3
+  :idempotent:
+  :tags: []
 - :name: pipeline_default:pipeline_metrics
   :worker_name: PipelineMetricsWorker
   :feature_category: :continuous_integration

app/workers/ci/retry_pipeline_worker.rb

+# frozen_string_literal: true
+
+module Ci
+  class RetryPipelineWorker # rubocop:disable Scalability/IdempotentWorker
+    include ::ApplicationWorker
+    include ::PipelineQueue
+
+    urgency :high
+    worker_resource_boundary :cpu
+
+    def perform(pipeline_id, user_id)
+      ::Ci::Pipeline.find_by_id(pipeline_id).try do |pipeline|
+        ::User.find_by_id(user_id).try do |user|
+          pipeline.retry_failed(user)
+        end
+      end
+    end
+  end
+end

spec/controllers/projects/pipelines_controller_spec.rb

@@ -856,7 +856,11 @@ RSpec.describe Projects::PipelinesController do
     let!(:pipeline) { create(:ci_pipeline, :failed, project: project) }
     let!(:build) { create(:ci_build, :failed, pipeline: pipeline) }
 
+    let(:worker_spy) { class_spy(::Ci::RetryPipelineWorker) }
+
     before do
+      stub_const('::Ci::RetryPipelineWorker', worker_spy)
+
       post :retry, params: {
                      namespace_id: project.namespace,
                      project_id: project,
@@ -865,9 +869,9 @@ RSpec.describe Projects::PipelinesController do
                    format: :json
     end
 
-    it 'retries a pipeline without returning any content' do
+    it 'retries a pipeline in the background without returning any content' do
       expect(response).to have_gitlab_http_status(:no_content)
-      expect(build.reload).to be_retried
+      expect(::Ci::RetryPipelineWorker).to have_received(:perform_async).with(pipeline.id, user.id)
     end
 
     context 'when builds are disabled' do

spec/workers/ci/retry_pipeline_worker_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Ci::RetryPipelineWorker do
+  describe '#perform' do
+    subject(:perform) { described_class.new.perform(pipeline_id, user_id) }
+
+    let(:pipeline) { create(:ci_pipeline) }
+
+    context 'when pipeline exists' do
+      let(:pipeline_id) { pipeline.id }
+
+      context 'when user exists' do
+        let(:user) { create(:user) }
+        let(:user_id) { user.id }
+
+        before do
+          pipeline.project.add_maintainer(user)
+        end
+
+        it 'retries the pipeline' do
+          expect(::Ci::Pipeline).to receive(:find_by_id).with(pipeline.id).and_return(pipeline)
+          expect(pipeline).to receive(:retry_failed).with(having_attributes(id: user_id))
+
+          perform
+        end
+      end
+
+      context 'when user does not exist' do
+        let(:user_id) { 1234 }
+
+        it 'does not retry the pipeline' do
+          expect(::Ci::Pipeline).to receive(:find_by_id).with(pipeline_id).and_return(pipeline)
+          expect(pipeline).not_to receive(:retry_failed).with(having_attributes(id: user_id))
+
+          perform
+        end
+      end
+    end
+
+    context 'when pipeline does not exist' do
+      let(:pipeline_id) { 1234 }
+      let(:user_id) { 1234 }
+
+      it 'returns false' do
+        expect(perform).to eq(nil)
+      end
+    end
+  end
+end