Adds graphql types

* Stages, jobs, and groups

app/graphql/resolvers/ci/pipeline_stages_resolver.rb

+# frozen_string_literal: true
+
+module Resolvers
+  module Ci
+    class PipelineStagesResolver < BaseResolver
+      include LooksAhead
+
+      alias_method :pipeline, :object
+
+      def resolve_with_lookahead
+        apply_lookahead(pipeline.stages)
+      end
+
+      def preloads
+        {
+          statuses: [:needs]
+        }
+      end
+    end
+  end
+end

app/graphql/types/ci/group_type.rb

+# frozen_string_literal: true
+
+module Types
+  module Ci
+    # rubocop: disable Graphql/AuthorizeTypes
+    class GroupType < BaseObject
+      graphql_name 'CiGroup'
+
+      field :name, GraphQL::STRING_TYPE, null: true,
+        description: 'Name of the job group'
+      field :size, GraphQL::INT_TYPE, null: true,
+        description: 'Size of the group'
+      field :jobs, Ci::JobType.connection_type, null: true,
+        description: 'Jobs in group'
+    end
+  end
+end

app/graphql/types/ci/job_type.rb

+# frozen_string_literal: true
+
+module Types
+  module Ci
+    # rubocop: disable Graphql/AuthorizeTypes
+    class JobType < BaseObject
+      graphql_name 'CiJob'
+
+      field :name, GraphQL::STRING_TYPE, null: true,
+        description: 'Name of the job'
+      field :needs, JobType.connection_type, null: true,
+        description: 'Builds that must complete before the jobs run'
+    end
+  end
+end

app/graphql/types/ci/pipeline_type.rb

@@ -37,6 +37,10 @@ module Types
             description: "Timestamp of the pipeline's completion"
       field :committed_at, Types::TimeType, null: true,
             description: "Timestamp of the pipeline's commit"
+      field :stages, Types::Ci::StageType.connection_type, null: true,
+            description: 'Stages of the pipeline',
+            extras: [:lookahead],
+            resolver: Resolvers::Ci::PipelineStagesResolver
 
       # TODO: Add triggering user as a type
     end

app/graphql/types/ci/stage_type.rb

+# frozen_string_literal: true
+
+module Types
+  module Ci
+    # rubocop: disable Graphql/AuthorizeTypes
+    class StageType < BaseObject
+      graphql_name 'CiStage'
+
+      field :name, GraphQL::STRING_TYPE, null: true,
+        description: 'Name of the stage'
+      field :groups, Ci::GroupType.connection_type, null: true,
+        description: 'Group of jobs for the stage'
+    end
+  end
+end

doc/api/graphql/reference/gitlab_schema.graphql

@@ -1347,6 +1347,212 @@ type Branch {
   name: String!
 }
 
+type CiGroup {
+  """
+  Jobs in group
+  """
+  jobs(
+    """
+    Returns the elements in the list that come after the specified cursor.
+    """
+    after: String
+
+    """
+    Returns the elements in the list that come before the specified cursor.
+    """
+    before: String
+
+    """
+    Returns the first _n_ elements from the list.
+    """
+    first: Int
+
+    """
+    Returns the last _n_ elements from the list.
+    """
+    last: Int
+  ): CiJobConnection
+
+  """
+  Name of the job group
+  """
+  name: String
+
+  """
+  Size of the group
+  """
+  size: Int
+}
+
+"""
+The connection type for CiGroup.
+"""
+type CiGroupConnection {
+  """
+  A list of edges.
+  """
+  edges: [CiGroupEdge]
+
+  """
+  A list of nodes.
+  """
+  nodes: [CiGroup]
+
+  """
+  Information to aid in pagination.
+  """
+  pageInfo: PageInfo!
+}
+
+"""
+An edge in a connection.
+"""
+type CiGroupEdge {
+  """
+  A cursor for use in pagination.
+  """
+  cursor: String!
+
+  """
+  The item at the end of the edge.
+  """
+  node: CiGroup
+}
+
+type CiJob {
+  """
+  Name of the job
+  """
+  name: String
+
+  """
+  Builds that must complete before the jobs run
+  """
+  needs(
+    """
+    Returns the elements in the list that come after the specified cursor.
+    """
+    after: String
+
+    """
+    Returns the elements in the list that come before the specified cursor.
+    """
+    before: String
+
+    """
+    Returns the first _n_ elements from the list.
+    """
+    first: Int
+
+    """
+    Returns the last _n_ elements from the list.
+    """
+    last: Int
+  ): CiJobConnection
+}
+
+"""
+The connection type for CiJob.
+"""
+type CiJobConnection {
+  """
+  A list of edges.
+  """
+  edges: [CiJobEdge]
+
+  """
+  A list of nodes.
+  """
+  nodes: [CiJob]
+
+  """
+  Information to aid in pagination.
+  """
+  pageInfo: PageInfo!
+}
+
+"""
+An edge in a connection.
+"""
+type CiJobEdge {
+  """
+  A cursor for use in pagination.
+  """
+  cursor: String!
+
+  """
+  The item at the end of the edge.
+  """
+  node: CiJob
+}
+
+type CiStage {
+  """
+  Group of jobs for the stage
+  """
+  groups(
+    """
+    Returns the elements in the list that come after the specified cursor.
+    """
+    after: String
+
+    """
+    Returns the elements in the list that come before the specified cursor.
+    """
+    before: String
+
+    """
+    Returns the first _n_ elements from the list.
+    """
+    first: Int
+
+    """
+    Returns the last _n_ elements from the list.
+    """
+    last: Int
+  ): CiGroupConnection
+
+  """
+  Name of the stage
+  """
+  name: String
+}
+
+"""
+The connection type for CiStage.
+"""
+type CiStageConnection {
+  """
+  A list of edges.
+  """
+  edges: [CiStageEdge]
+
+  """
+  A list of nodes.
+  """
+  nodes: [CiStage]
+
+  """
+  Information to aid in pagination.
+  """
+  pageInfo: PageInfo!
+}
+
+"""
+An edge in a connection.
+"""
+type CiStageEdge {
+  """
+  A cursor for use in pagination.
+  """
+  cursor: String!
+
+  """
+  The item at the end of the edge.
+  """
+  node: CiStage
+}
+
 type Commit {
   """
   Author of the commit
@@ -9850,6 +10056,31 @@ type Pipeline {
   """
   sha: String!
 
+  """
+  Stages of the pipeline
+  """
+  stages(
+    """
+    Returns the elements in the list that come after the specified cursor.
+    """
+    after: String
+
+    """
+    Returns the elements in the list that come before the specified cursor.
+    """
+    before: String
+
+    """
+    Returns the first _n_ elements from the list.
+    """
+    first: Int
+
+    """
+    Returns the last _n_ elements from the list.
+    """
+    last: Int
+  ): CiStageConnection
+
   """
   Timestamp when the pipeline was started
   """

doc/api/graphql/reference/index.md

@@ -231,6 +231,25 @@ Autogenerated return type of BoardListUpdateLimitMetrics
 | `commit` | Commit | Commit for the branch |
 | `name` | String! | Name of the branch |
 
+## CiGroup
+
+| Name  | Type  | Description |
+| ---   |  ---- | ----------  |
+| `name` | String | Name of the job group |
+| `size` | Int | Size of the group |
+
+## CiJob
+
+| Name  | Type  | Description |
+| ---   |  ---- | ----------  |
+| `name` | String | Name of the job |
+
+## CiStage
+
+| Name  | Type  | Description |
+| ---   |  ---- | ----------  |
+| `name` | String | Name of the stage |
+
 ## Commit
 
 | Name  | Type  | Description |

spec/graphql/types/ci/group_type_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Types::Ci::GroupType do
+  specify { expect(described_class.graphql_name).to eq('CiGroup') }
+
+  it 'exposes the expected fields' do
+    expected_fields = %i[
+      name
+      size
+      jobs
+    ]
+
+    expect(described_class).to have_graphql_fields(*expected_fields)
+  end
+end

spec/graphql/types/ci/job_type_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Types::Ci::JobType do
+  specify { expect(described_class.graphql_name).to eq('CiJob') }
+
+  it 'exposes the expected fields' do
+    expected_fields = %i[
+      name
+      needs
+    ]
+
+    expect(described_class).to have_graphql_fields(*expected_fields)
+  end
+end

spec/graphql/types/ci/stage_type_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Types::Ci::StageType do
+  specify { expect(described_class.graphql_name).to eq('CiStage') }
+
+  it 'exposes the expected fields' do
+    expected_fields = %i[
+      name
+      groups
+    ]
+
+    expect(described_class).to have_graphql_fields(*expected_fields)
+  end
+end

spec/requests/api/graphql/ci/groups_spec.rb

+# frozen_string_literal: true
+require 'spec_helper'
+
+RSpec.describe 'Query.project.pipeline.stages.groups' do
+  include GraphqlHelpers
+
+  let(:project) { create(:project, :repository, :public) }
+  let(:user) { create(:user) }
+  let(:pipeline) { create(:ci_pipeline, project: project, user: user) }
+  let(:group_graphql_data) { graphql_data.dig('project', 'pipeline', 'stages', 'nodes', 0, 'groups', 'nodes') }
+
+  let(:params) { {} }
+
+  let(:fields) do
+    <<~QUERY
+      nodes {
+        #{all_graphql_fields_for('CiGroup')}
+      }
+    QUERY
+  end
+
+  let(:query) do
+    %(
+      query {
+        project(fullPath: "#{project.full_path}") {
+          pipeline(iid: "#{pipeline.iid}") {
+            stages {
+              nodes {
+                groups {
+                  #{fields}
+                }
+              }
+            }
+          }
+        }
+      }
+    )
+  end
+
+  before do
+    create(:commit_status, pipeline: pipeline, name: 'rspec 0 2')
+    create(:commit_status, pipeline: pipeline, name: 'rspec 0 1')
+    create(:commit_status, pipeline: pipeline, name: 'spinach 0 1')
+    post_graphql(query, current_user: user)
+  end
+
+  it_behaves_like 'a working graphql query'
+
+  it 'returns a array of jobs belonging to a pipeline' do
+    expect(group_graphql_data.map { |g| g.slice('name', 'size') }).to eq([
+      { 'name' => 'rspec', 'size' => 2 },
+      { 'name' => 'spinach', 'size' => 1 }
+    ])
+  end
+end

spec/requests/api/graphql/ci/jobs_spec.rb

+# frozen_string_literal: true
+require 'spec_helper'
+
+RSpec.describe 'Query.project.pipeline.stages.groups.jobs' do
+  include GraphqlHelpers
+
+  let(:project) { create(:project, :repository, :public) }
+  let(:user) { create(:user) }
+  let(:pipeline) do
+    pipeline = create(:ci_pipeline, project: project, user: user)
+    stage = create(:ci_stage_entity, pipeline: pipeline, name: 'first')
+    create(:commit_status, stage_id: stage.id, pipeline: pipeline, name: 'my test job')
+
+    pipeline
+  end
+
+  def first(field)
+    [field.pluralize, 'nodes', 0]
+  end
+
+  let(:jobs_graphql_data) { graphql_data.dig(*%w[project pipeline], *first('stage'), *first('group'), 'jobs', 'nodes') }
+
+  let(:query) do
+    %(
+      query {
+        project(fullPath: "#{project.full_path}") {
+          pipeline(iid: "#{pipeline.iid}") {
+            stages {
+              nodes {
+                name
+                groups {
+                  nodes {
+                    name
+                    jobs {
+                      nodes {
+                        name
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    )
+  end
+
+  it 'returns the jobs of a pipeline stage' do
+    post_graphql(query, current_user: user)
+
+    expect(jobs_graphql_data).to contain_exactly(a_hash_including('name' => 'my test job'))
+  end
+
+  context 'when fetching jobs from the pipeline' do
+    it 'avoids N+1 queries' do
+      control_count = ActiveRecord::QueryRecorder.new do
+        post_graphql(query, current_user: user)
+      end
+
+      build_stage = create(:ci_stage_entity, name: 'build', pipeline: pipeline)
+      test_stage = create(:ci_stage_entity, name: 'test', pipeline: pipeline)
+      create(:commit_status, pipeline: pipeline, stage_id: build_stage.id, name: 'docker 1 2')
+      create(:commit_status, pipeline: pipeline, stage_id: build_stage.id, name: 'docker 2 2')
+      create(:commit_status, pipeline: pipeline, stage_id: test_stage.id, name: 'rspec 1 2')
+      create(:commit_status, pipeline: pipeline, stage_id: test_stage.id, name: 'rspec 2 2')
+
+      expect do
+        post_graphql(query, current_user: user)
+      end.not_to exceed_query_limit(control_count)
+
+      expect(response).to have_gitlab_http_status(:ok)
+
+      build_stage = graphql_data.dig('project', 'pipeline', 'stages', 'nodes').find do |stage|
+        stage['name'] == 'build'
+      end
+      test_stage = graphql_data.dig('project', 'pipeline', 'stages', 'nodes').find do |stage|
+        stage['name'] == 'test'
+      end
+      docker_group = build_stage.dig('groups', 'nodes').first
+      rspec_group = test_stage.dig('groups', 'nodes').first
+
+      expect(docker_group['name']).to eq('docker')
+      expect(rspec_group['name']).to eq('rspec')
+
+      docker_jobs = docker_group.dig('jobs', 'nodes')
+      rspec_jobs = rspec_group.dig('jobs', 'nodes')
+
+      expect(docker_jobs).to eq([{ 'name' => 'docker 1 2' }, { 'name' => 'docker 2 2' }])
+      expect(rspec_jobs).to eq([{ 'name' => 'rspec 1 2' }, { 'name' => 'rspec 2 2' }])
+    end
+  end
+end

spec/requests/api/graphql/ci/stages_spec.rb

+# frozen_string_literal: true
+require 'spec_helper'
+
+RSpec.describe 'Query.project.pipeline.stages' do
+  include GraphqlHelpers
+
+  let(:project) { create(:project, :repository, :public) }
+  let(:user) { create(:user) }
+  let(:pipeline) { create(:ci_pipeline, project: project, user: user) }
+  let(:stage_graphql_data) { graphql_data['project']['pipeline']['stages'] }
+
+  let(:params) { {} }
+
+  let(:fields) do
+    <<~QUERY
+      nodes {
+        #{all_graphql_fields_for('CiStage')}
+      }
+    QUERY
+  end
+
+  let(:query) do
+    %(
+      query {
+        project(fullPath: "#{project.full_path}") {
+          pipeline(iid: "#{pipeline.iid}") {
+            stages {
+              #{fields}
+            }
+          }
+        }
+      }
+    )
+  end
+
+  before do
+    create(:ci_stage_entity, pipeline: pipeline, name: 'deploy')
+    post_graphql(query, current_user: user)
+  end
+
+  it_behaves_like 'a working graphql query'
+
+  it 'returns the stage of a pipeline' do
+    expect(stage_graphql_data['nodes'].first['name']).to eq('deploy')
+  end
+end