Implement DAG pipeline serializer

Add DAG entities for pipeline, stage, group, job.

app/controllers/projects/pipelines_controller.rb

@@ -95,7 +95,14 @@ class Projects::PipelinesController < Projects::ApplicationController
   end
 
   def dag
-    render_show
+    respond_to do |format|
+      format.html { render_show }
+      format.json do
+        render json: Ci::DagPipelineSerializer
+          .new(project: @project, current_user: @current_user)
+          .represent(@pipeline)
+      end
+    end
   end
 
   def failures

app/models/ci/processable.rb

@@ -4,12 +4,8 @@ module Ci
   class Processable < ::CommitStatus
     include Gitlab::Utils::StrongMemoize
 
-    has_many :needs, class_name: 'Ci::BuildNeed', foreign_key: :build_id, inverse_of: :build
-
     accepts_nested_attributes_for :needs
 
-    enum scheduling_type: { stage: 0, dag: 1 }, _prefix: true
-
     scope :preload_needs, -> { preload(:needs) }
 
     scope :with_needs, -> (names = nil) do

app/models/commit_status.rb

@@ -14,6 +14,10 @@ class CommitStatus < ApplicationRecord
   belongs_to :pipeline, class_name: 'Ci::Pipeline', foreign_key: :commit_id
   belongs_to :auto_canceled_by, class_name: 'Ci::Pipeline'
 
+  has_many :needs, class_name: 'Ci::BuildNeed', foreign_key: :build_id, inverse_of: :build
+
+  enum scheduling_type: { stage: 0, dag: 1 }, _prefix: true
+
   delegate :commit, to: :pipeline
   delegate :sha, :short_sha, :before_sha, to: :pipeline
 

app/serializers/ci/dag_job_entity.rb

@@ -3,6 +3,7 @@
 module Ci
   class DagJobEntity < Grape::Entity
     expose :name
+    expose :scheduling_type
 
     expose :needs, if: -> (job, _) { job.scheduling_type_dag? } do |job|
       job.needs.pluck(:name) # rubocop: disable CodeReuse/ActiveRecord

app/serializers/ci/dag_pipeline_entity.rb

@@ -2,12 +2,12 @@
 
 module Ci
   class DagPipelineEntity < Grape::Entity
-    expose :ordered_stages_with_preloads, as: :stages, using: Ci::DagStageEntity
+    expose :stages_with_preloads, as: :stages, using: Ci::DagStageEntity
 
     private
 
-    def ordered_stages_with_preloads
-      object.ordered_stages.preload(preloaded_relations) # rubocop: disable CodeReuse/ActiveRecord
+    def stages_with_preloads
+      object.stages.preload(preloaded_relations) # rubocop: disable CodeReuse/ActiveRecord
     end
 
     def preloaded_relations

app/views/projects/pipelines/_with_tabs.html.haml

@@ -82,6 +82,7 @@
 
   - if dag_pipeline_tab_enabled
     #js-tab-dag.tab-pane
+      #js-pipeline-dag-vue{ data: { pipeline_data_path: dag_project_pipeline_path(@project, @pipeline) } }
 
   #js-tab-tests.tab-pane
     #js-pipeline-tests-detail

changelogs/unreleased/data-endpoint-for-dag-visualization-2.yml

+---
+title: Add DAG serializer for pipelines controller
+merge_request: 31583
+author:
+type: added

spec/controllers/projects/pipelines_controller_spec.rb

@@ -548,6 +548,39 @@ describe Projects::PipelinesController do
     end
   end
 
+  describe 'GET dag.json' do
+    let(:pipeline) { create(:ci_pipeline, project: project) }
+
+    before do
+      create_build('build', 1, 'build')
+      create_build('test', 2, 'test', scheduling_type: 'dag').tap do |job|
+        create(:ci_build_need, build: job, name: 'build')
+      end
+    end
+
+    it 'returns the pipeline with DAG serialization' do
+      get :dag, params: { namespace_id: project.namespace, project_id: project, id: pipeline }, format: :json
+
+      expect(response).to have_gitlab_http_status(:ok)
+
+      expect(json_response.fetch('stages')).not_to be_empty
+
+      build_stage = json_response['stages'].first
+      expect(build_stage.fetch('name')).to eq 'build'
+      expect(build_stage.fetch('groups').first.fetch('jobs'))
+        .to eq [{ 'name' => 'build', 'scheduling_type' => 'stage' }]
+
+      test_stage = json_response['stages'].last
+      expect(test_stage.fetch('name')).to eq 'test'
+      expect(test_stage.fetch('groups').first.fetch('jobs'))
+        .to eq [{ 'name' => 'test', 'scheduling_type' => 'dag', 'needs' => ['build'] }]
+    end
+
+    def create_build(stage, stage_idx, name, params = {})
+      create(:ci_build, pipeline: pipeline, stage: stage, stage_idx: stage_idx, name: name, **params)
+    end
+  end
+
   describe 'GET stages.json' do
     let(:pipeline) { create(:ci_pipeline, project: project) }
 

spec/lib/gitlab/import_export/all_models.yml

@@ -236,6 +236,7 @@ statuses:
 - stage
 - user
 - auto_canceled_by
+- needs
 variables:
 - project
 triggers:

spec/serializers/ci/dag_job_entity_spec.rb

@@ -16,14 +16,23 @@ describe Ci::DagJobEntity do
     end
 
     context 'when job is stage scheduled' do
+      it 'contains the name scheduling_type' do
+        expect(subject[:scheduling_type]).to eq 'stage'
+      end
+
       it 'does not expose needs' do
         expect(subject).not_to include(:needs)
       end
     end
 
     context 'when job is dag scheduled' do
+      let(:job) { create(:ci_build, scheduling_type: 'dag') }
+
+      it 'contains the name scheduling_type' do
+        expect(subject[:scheduling_type]).to eq 'dag'
+      end
+
       context 'when job has needs' do
-        let(:job) { create(:ci_build, scheduling_type: 'dag') }
         let!(:need) { create(:ci_build_need, build: job, name: 'compile') }
 
         it 'exposes the array of needs' do
@@ -32,8 +41,6 @@ describe Ci::DagJobEntity do
       end
 
       context 'when job has empty needs' do
-        let(:job) { create(:ci_build, scheduling_type: 'dag') }
-
         it 'exposes an empty array of needs' do
           expect(subject[:needs]).to eq []
         end

spec/serializers/ci/dag_pipeline_entity_spec.rb

@@ -32,13 +32,14 @@ describe Ci::DagPipelineEntity do
       end
     end
 
-    context 'when pipeline has parallel jobs and DAG needs' do
+    context 'when pipeline has parallel jobs, DAG needs and GenericCommitStatus' do
       let!(:stage_build)  { create(:ci_stage_entity, name: 'build',  position: 1, pipeline: pipeline) }
       let!(:stage_test)   { create(:ci_stage_entity, name: 'test',   position: 2, pipeline: pipeline) }
       let!(:stage_deploy) { create(:ci_stage_entity, name: 'deploy', position: 3, pipeline: pipeline) }
 
-      let!(:job_build_1) { create(:ci_build, name: 'build 1', stage: 'build', pipeline: pipeline) }
-      let!(:job_build_2) { create(:ci_build, name: 'build 2', stage: 'build', pipeline: pipeline) }
+      let!(:job_build_1)   { create(:ci_build, name: 'build 1', stage: 'build', pipeline: pipeline) }
+      let!(:job_build_2)   { create(:ci_build, name: 'build 2', stage: 'build', pipeline: pipeline) }
+      let!(:commit_status) { create(:generic_commit_status, stage: 'build', pipeline: pipeline) }
 
       let!(:job_rspec_1) { create(:ci_build, name: 'rspec 1/2', stage: 'test', pipeline: pipeline) }
       let!(:job_rspec_2) { create(:ci_build, name: 'rspec 2/2', stage: 'test', pipeline: pipeline) }
@@ -75,22 +76,52 @@ describe Ci::DagPipelineEntity do
             {
               name: 'build',
               groups: [
-                { name: 'build 1', size: 1, jobs: [{ name: 'build 1' }] },
-                { name: 'build 2', size: 1, jobs: [{ name: 'build 2' }] }
+                {
+                  name: 'build 1', size: 1, jobs: [
+                    { name: 'build 1', scheduling_type: 'stage' }
+                  ]
+                },
+                {
+                  name: 'build 2', size: 1, jobs: [
+                    { name: 'build 2', scheduling_type: 'stage' }
+                  ]
+                },
+                {
+                  name: 'generic', size: 1, jobs: [
+                    { name: 'generic', scheduling_type: nil }
+                  ]
+                }
               ]
             },
             {
               name: 'test',
               groups: [
-                { name: 'jest', size: 1, jobs: [{ name: 'jest', needs: ['build 1'] }] },
-                { name: 'rspec', size: 2, jobs: [{ name: 'rspec 1/2' }, { name: 'rspec 2/2' }] }
+                {
+                  name: 'jest', size: 1, jobs: [
+                    { name: 'jest', scheduling_type: 'dag', needs: ['build 1'] }
+                  ]
+                },
+                {
+                  name: 'rspec', size: 2, jobs: [
+                    { name: 'rspec 1/2', scheduling_type: 'stage' },
+                    { name: 'rspec 2/2', scheduling_type: 'stage' }
+                  ]
+                }
               ]
             },
             {
               name: 'deploy',
               groups: [
-                { name: 'deploy_js', size: 1, jobs: [{ name: 'deploy_js', needs: ['jest'] }] },
-                { name: 'deploy_ruby', size: 1, jobs: [{ name: 'deploy_ruby', needs: ['rspec 1/2', 'rspec 2/2'] }] }
+                {
+                  name: 'deploy_js', size: 1, jobs: [
+                    { name: 'deploy_js', scheduling_type: 'dag', needs: ['jest'] }
+                  ]
+                },
+                {
+                  name: 'deploy_ruby', size: 1, jobs: [
+                    { name: 'deploy_ruby', scheduling_type: 'dag', needs: ['rspec 1/2', 'rspec 2/2'] }
+                  ]
+                }
               ]
             }
           ]