select group runners also in register_job_service

app/services/ci/register_job_service.rb

@@ -17,6 +17,8 @@ module Ci
       builds =
         if runner.shared?
           builds_for_shared_runner
+        elsif runner.group?
+          builds_for_group_runner
         else
           builds_for_specific_runner
         end
@@ -69,16 +71,33 @@ module Ci
     private
 
     def builds_for_shared_runner
-      new_builds.
-        # don't run projects which have not enabled shared runners and builds
-        joins(:project).where(projects: { shared_runners_enabled: true, pending_delete: false })
+      builds_for_scheduled_runner(
+        running_builds_for_shared_runners,
+        projects: { shared_runners_enabled: true }
+      )
+    end
+
+    def builds_for_group_runner
+      builds_for_scheduled_runner(
+        running_builds_for_group_runners,
+        projects: { group_runners_enabled: true }
+      )
+    end
+
+    def builds_for_scheduled_runner(build_join, project_where)
+      project_where = project_where.deep_merge(projects: { pending_delete: false })
+
+      # don't run projects which have not enabled group runners and builds
+      builds = new_builds
+        .joins(:project).where(project_where)
         .joins('LEFT JOIN project_features ON ci_builds.project_id = project_features.project_id')
-        .where('project_features.builds_access_level IS NULL or project_features.builds_access_level > 0').
+        .where('project_features.builds_access_level IS NULL or project_features.builds_access_level > 0')
 
-        # Implement fair scheduling
-        # this returns builds that are ordered by number of running builds
-        # we prefer projects that don't use shared runners at all
-        joins("LEFT JOIN (#{running_builds_for_shared_runners.to_sql}) AS project_builds ON ci_builds.project_id=project_builds.project_id")
+      # Implement fair scheduling
+      # this returns builds that are ordered by number of running builds
+      # we prefer projects that don't use group runners at all
+      builds
+        .joins("LEFT JOIN (#{build_join.to_sql}) AS project_builds ON ci_builds.project_id=project_builds.project_id")
         .order('COALESCE(project_builds.running_builds, 0) ASC', 'ci_builds.id ASC')
     end
 
@@ -87,7 +106,15 @@ module Ci
     end
 
     def running_builds_for_shared_runners
-      Ci::Build.running.where(runner: Ci::Runner.shared)
+      running_builds_for_runners(Ci::Runner.shared)
+    end
+
+    def running_builds_for_group_runners
+      running_builds_for_runners(Ci::Runner.joins(:runner_groups))
+    end
+
+    def running_builds_for_runners(runners)
+      Ci::Build.running.where(runner: runners)
         .group(:project_id).select(:project_id, 'count(*) AS running_builds')
     end
 

spec/services/ci/register_job_service_spec.rb

@@ -2,11 +2,13 @@ require 'spec_helper'
 
 module Ci
   describe RegisterJobService do
-    let!(:project) { FactoryBot.create :project, shared_runners_enabled: false }
-    let!(:pipeline) { FactoryBot.create :ci_pipeline, project: project }
-    let!(:pending_job) { FactoryBot.create :ci_build, pipeline: pipeline }
-    let!(:shared_runner) { FactoryBot.create(:ci_runner, is_shared: true) }
-    let!(:specific_runner) { FactoryBot.create(:ci_runner, is_shared: false) }
+    let!(:project) { create :project, shared_runners_enabled: false }
+    let!(:group) { create :group }
+    let!(:pipeline) { create :ci_pipeline, project: project }
+    let!(:pending_job) { create :ci_build, pipeline: pipeline }
+    let!(:shared_runner) { create :ci_runner, is_shared: true }
+    let!(:specific_runner) { create :ci_runner, is_shared: false }
+    let!(:group_runner) { create :ci_runner, groups: [group] }
 
     before do
       specific_runner.assign_to(project)
@@ -167,6 +169,73 @@ module Ci
         end
       end
 
+      context 'allow group runners' do
+        before do
+          project.update!(group_runners_enabled: true, group: group)
+        end
+
+        context 'for multiple builds' do
+          let!(:project2) { create :project, group_runners_enabled: true, group: group }
+          let!(:pipeline2) { create :ci_pipeline, project: project2 }
+          let!(:project3) { create :project, group_runners_enabled: true, group: group }
+          let!(:pipeline3) { create :ci_pipeline, project: project3 }
+          let!(:build1_project1) { pending_job }
+          let!(:build2_project1) { create :ci_build, pipeline: pipeline }
+          let!(:build3_project1) { create :ci_build, pipeline: pipeline }
+          let!(:build1_project2) { create :ci_build, pipeline: pipeline2 }
+          let!(:build2_project2) { create :ci_build, pipeline: pipeline2 }
+          let!(:build1_project3) { create :ci_build, pipeline: pipeline3 }
+
+          it 'prefers projects without builds first' do
+            # it gets for one build from each of the projects
+            expect(execute(group_runner)).to eq(build1_project1)
+            expect(execute(group_runner)).to eq(build1_project2)
+            expect(execute(group_runner)).to eq(build1_project3)
+
+            # then it gets a second build from each of the projects
+            expect(execute(group_runner)).to eq(build2_project1)
+            expect(execute(group_runner)).to eq(build2_project2)
+
+            # in the end the third build
+            expect(execute(group_runner)).to eq(build3_project1)
+          end
+
+          it 'equalises number of running builds' do
+            # after finishing the first build for project 1, get a second build from the same project
+            expect(execute(group_runner)).to eq(build1_project1)
+            build1_project1.reload.success
+            expect(execute(group_runner)).to eq(build2_project1)
+
+            expect(execute(group_runner)).to eq(build1_project2)
+            build1_project2.reload.success
+            expect(execute(group_runner)).to eq(build2_project2)
+            expect(execute(group_runner)).to eq(build1_project3)
+            expect(execute(group_runner)).to eq(build3_project1)
+          end
+        end
+
+        context 'group runner' do
+          let(:build) { execute(group_runner) }
+
+          it { expect(build).to be_kind_of(Build) }
+          it { expect(build).to be_valid }
+          it { expect(build).to be_running }
+          it { expect(build.runner).to eq(group_runner) }
+        end
+      end
+
+      context 'disallow group runners' do
+        before do
+          project.update(group_runners_enabled: false)
+        end
+
+        context 'group runner' do
+          let(:build) { execute(group_runner) }
+
+          it { expect(build).to be_nil }
+        end
+      end
+
       context 'when first build is stalled' do
         before do
           pending_job.update(lock_version: 0)