Merge branch '57115-just-in-time-k8s-resource-creation' into 'master'

Create project-specific Kubernetes resources just-in-time

See merge request gitlab-org/gitlab-ce!25586

25 files changed, 621 insertions, 17 deletions

diff --git a/spec/factories/ci/builds.rb b/spec/factories/ci/builds.rb
index 0b3e67b4987..067391c1179 100644
--- a/spec/factories/ci/builds.rb
+++ b/spec/factories/ci/builds.rb
@@ -75,6 +75,10 @@ FactoryBot.define do
       status 'created'
     end
 
+    trait :preparing do
+      status 'preparing'
+    end
+
     trait :scheduled do
       schedulable
       status 'scheduled'
diff --git a/spec/factories/ci/pipelines.rb b/spec/factories/ci/pipelines.rb
index ee5d27355f1..aa5ccbda6cd 100644
--- a/spec/factories/ci/pipelines.rb
+++ b/spec/factories/ci/pipelines.rb
@@ -50,6 +50,14 @@ FactoryBot.define do
         failure_reason :config_error
       end
 
+      trait :created do
+        status :created
+      end
+
+      trait :preparing do
+        status :preparing
+      end
+
       trait :blocked do
         status :manual
       end
diff --git a/spec/factories/clusters/clusters.rb b/spec/factories/clusters/clusters.rb
index a2e5f4862db..1cc3c0e03d8 100644
--- a/spec/factories/clusters/clusters.rb
+++ b/spec/factories/clusters/clusters.rb
@@ -12,7 +12,7 @@ FactoryBot.define do
       cluster_type { Clusters::Cluster.cluster_types[:project_type] }
 
       before(:create) do |cluster, evaluator|
-        cluster.projects << create(:project, :repository)
+        cluster.projects << create(:project, :repository) unless cluster.projects.present?
       end
     end
 
@@ -20,7 +20,7 @@ FactoryBot.define do
       cluster_type { Clusters::Cluster.cluster_types[:group_type] }
 
       before(:create) do |cluster, evalutor|
-        cluster.groups << create(:group)
+        cluster.groups << create(:group) unless cluster.groups.present?
       end
     end
 
diff --git a/spec/factories/commit_statuses.rb b/spec/factories/commit_statuses.rb
index 381bf07f6a0..848a31e96c1 100644
--- a/spec/factories/commit_statuses.rb
+++ b/spec/factories/commit_statuses.rb
@@ -33,6 +33,10 @@ FactoryBot.define do
       status 'pending'
     end
 
+    trait :preparing do
+      status 'preparing'
+    end
+
     trait :created do
       status 'created'
     end
diff --git a/spec/features/projects/badges/pipeline_badge_spec.rb b/spec/features/projects/badges/pipeline_badge_spec.rb
index dee81898928..4ac4e8f0fcb 100644
--- a/spec/features/projects/badges/pipeline_badge_spec.rb
+++ b/spec/features/projects/badges/pipeline_badge_spec.rb
@@ -41,6 +41,25 @@ describe 'Pipeline Badge' do
       end
     end
 
+    context 'when the pipeline is preparing' do
+      let!(:job) { create(:ci_build, status: 'created', pipeline: pipeline) }
+
+      before do
+        # Prevent skipping directly to 'pending'
+        allow(Ci::BuildPrepareWorker).to receive(:perform_async)
+        allow(job).to receive(:prerequisites).and_return([double])
+      end
+
+      it 'displays the preparing badge' do
+        job.enqueue
+
+        visit pipeline_project_badges_path(project, ref: ref, format: :svg)
+
+        expect(page.status_code).to eq(200)
+        expect_badge('preparing')
+      end
+    end
+
     context 'when the pipeline is running' do
       it 'shows displays so on the badge' do
         create(:ci_build, pipeline: pipeline, name: 'second build', status_event: 'run')
diff --git a/spec/features/projects/pipelines/pipeline_spec.rb b/spec/features/projects/pipelines/pipeline_spec.rb
index 5d2a99f40b7..9fdf78baa1e 100644
--- a/spec/features/projects/pipelines/pipeline_spec.rb
+++ b/spec/features/projects/pipelines/pipeline_spec.rb
@@ -24,6 +24,11 @@ describe 'Pipeline', :js do
              pipeline: pipeline, stage: 'test', name: 'test')
     end
 
+    let!(:build_preparing) do
+      create(:ci_build, :preparing,
+             pipeline: pipeline, stage: 'deploy', name: 'prepare')
+    end
+
     let!(:build_running) do
       create(:ci_build, :running,
              pipeline: pipeline, stage: 'deploy', name: 'deploy')
@@ -109,6 +114,24 @@ describe 'Pipeline', :js do
         end
       end
 
+      context 'when pipeline has preparing builds' do
+        it 'shows a preparing icon and a cancel action' do
+          page.within('#ci-badge-prepare') do
+            expect(page).to have_selector('.js-ci-status-icon-preparing')
+            expect(page).to have_selector('.js-icon-cancel')
+            expect(page).to have_content('prepare')
+          end
+        end
+
+        it 'cancels the preparing build and shows retry button' do
+          find('#ci-badge-deploy .ci-action-icon-container').click
+
+          page.within('#ci-badge-deploy') do
+            expect(page).to have_css('.js-icon-retry')
+          end
+        end
+      end
+
       context 'when pipeline has successful builds' do
         it 'shows the success icon and a retry action for the successful build' do
           page.within('#ci-badge-build') do
diff --git a/spec/features/projects/pipelines/pipelines_spec.rb b/spec/features/projects/pipelines/pipelines_spec.rb
index 88d7c9ef8bd..9dc505573d4 100644
--- a/spec/features/projects/pipelines/pipelines_spec.rb
+++ b/spec/features/projects/pipelines/pipelines_spec.rb
@@ -282,6 +282,30 @@ describe 'Pipelines', :js do
       end
 
       context 'for generic statuses' do
+        context 'when preparing' do
+          let!(:pipeline) do
+            create(:ci_empty_pipeline,
+              status: 'preparing', project: project)
+          end
+
+          let!(:status) do
+            create(:generic_commit_status,
+              :preparing, pipeline: pipeline)
+          end
+
+          before do
+            visit_project_pipelines
+          end
+
+          it 'is cancelable' do
+            expect(page).to have_selector('.js-pipelines-cancel-button')
+          end
+
+          it 'shows the pipeline as preparing' do
+            expect(page).to have_selector('.ci-preparing')
+          end
+        end
+
         context 'when running' do
           let!(:running) do
             create(:generic_commit_status,
diff --git a/spec/lib/gitlab/badge/pipeline/template_spec.rb b/spec/lib/gitlab/badge/pipeline/template_spec.rb
index 20fa4f879c3..bcef0b7e120 100644
--- a/spec/lib/gitlab/badge/pipeline/template_spec.rb
+++ b/spec/lib/gitlab/badge/pipeline/template_spec.rb
@@ -59,6 +59,16 @@ describe Gitlab::Badge::Pipeline::Template do
       end
     end
 
+    context 'when status is preparing' do
+      before do
+        allow(badge).to receive(:status).and_return('preparing')
+      end
+
+      it 'has expected color' do
+        expect(template.value_color).to eq '#dfb317'
+      end
+    end
+
     context 'when status is unknown' do
       before do
         allow(badge).to receive(:status).and_return('unknown')
diff --git a/spec/lib/gitlab/ci/build/prerequisite/factory_spec.rb b/spec/lib/gitlab/ci/build/prerequisite/factory_spec.rb
new file mode 100644
index 00000000000..5187f99a441
--- /dev/null
+++ b/spec/lib/gitlab/ci/build/prerequisite/factory_spec.rb
@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Ci::Build::Prerequisite::Factory do
+  let(:build) { create(:ci_build) }
+
+  describe '.for_build' do
+    let(:kubernetes_namespace) do
+      instance_double(
+        Gitlab::Ci::Build::Prerequisite::KubernetesNamespace,
+        unmet?: unmet)
+    end
+
+    subject { described_class.new(build).unmet }
+
+    before do
+      expect(Gitlab::Ci::Build::Prerequisite::KubernetesNamespace)
+        .to receive(:new).with(build).and_return(kubernetes_namespace)
+    end
+
+    context 'prerequisite is unmet' do
+      let(:unmet) { true }
+
+      it { is_expected.to eq [kubernetes_namespace] }
+    end
+
+    context 'prerequisite is met' do
+      let(:unmet) { false }
+
+      it { is_expected.to be_empty }
+    end
+  end
+end
diff --git a/spec/lib/gitlab/ci/build/prerequisite/kubernetes_namespace_spec.rb b/spec/lib/gitlab/ci/build/prerequisite/kubernetes_namespace_spec.rb
new file mode 100644
index 00000000000..62dcd80fad7
--- /dev/null
+++ b/spec/lib/gitlab/ci/build/prerequisite/kubernetes_namespace_spec.rb
@@ -0,0 +1,85 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Ci::Build::Prerequisite::KubernetesNamespace do
+  let(:build) { create(:ci_build) }
+
+  describe '#unmet?' do
+    subject { described_class.new(build).unmet? }
+
+    context 'build has no deployment' do
+      before do
+        expect(build.deployment).to be_nil
+      end
+
+      it { is_expected.to be_falsey }
+    end
+
+    context 'build has a deployment' do
+      let!(:deployment) { create(:deployment, deployable: build) }
+
+      context 'and a cluster to deploy to' do
+        let(:cluster) { create(:cluster, projects: [build.project]) }
+
+        before do
+          allow(build.deployment).to receive(:cluster).and_return(cluster)
+        end
+
+        it { is_expected.to be_truthy }
+
+        context 'and a namespace is already created for this project' do
+          let!(:kubernetes_namespace) { create(:cluster_kubernetes_namespace, cluster: cluster, project: build.project) }
+
+          it { is_expected.to be_falsey }
+        end
+      end
+
+      context 'and no cluster to deploy to' do
+        before do
+          expect(deployment.cluster).to be_nil
+        end
+
+        it { is_expected.to be_falsey }
+      end
+    end
+  end
+
+  describe '#complete!' do
+    let!(:deployment) { create(:deployment, deployable: build) }
+    let(:service) { double(execute: true) }
+
+    subject { described_class.new(build).complete! }
+
+    context 'completion is required' do
+      let(:cluster) { create(:cluster, projects: [build.project]) }
+
+      before do
+        allow(build.deployment).to receive(:cluster).and_return(cluster)
+      end
+
+      it 'creates a kubernetes namespace' do
+        expect(Clusters::Gcp::Kubernetes::CreateOrUpdateNamespaceService)
+          .to receive(:new)
+          .with(cluster: cluster, kubernetes_namespace: instance_of(Clusters::KubernetesNamespace))
+          .and_return(service)
+
+        expect(service).to receive(:execute).once
+
+        subject
+      end
+    end
+
+    context 'completion is not required' do
+      before do
+        expect(deployment.cluster).to be_nil
+      end
+
+      it 'does not create a namespace' do
+        expect(Clusters::Gcp::Kubernetes::CreateOrUpdateNamespaceService).not_to receive(:new)
+
+        subject
+      end
+    end
+  end
+end
diff --git a/spec/lib/gitlab/ci/status/build/preparing_spec.rb b/spec/lib/gitlab/ci/status/build/preparing_spec.rb
new file mode 100644
index 00000000000..4d8945845ba
--- /dev/null
+++ b/spec/lib/gitlab/ci/status/build/preparing_spec.rb
@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Ci::Status::Build::Preparing do
+  subject do
+    described_class.new(double('subject'))
+  end
+
+  describe '#illustration' do
+    it { expect(subject.illustration).to include(:image, :size, :title, :content) }
+  end
+
+  describe '.matches?' do
+    subject { described_class.matches?(build, nil) }
+
+    context 'when build is preparing' do
+      let(:build) { create(:ci_build, :preparing) }
+
+      it 'is a correct match' do
+        expect(subject).to be true
+      end
+    end
+
+    context 'when build is not preparing' do
+      let(:build) { create(:ci_build, :success) }
+
+      it 'does not match' do
+        expect(subject).to be false
+      end
+    end
+  end
+end
diff --git a/spec/lib/gitlab/ci/status/preparing_spec.rb b/spec/lib/gitlab/ci/status/preparing_spec.rb
new file mode 100644
index 00000000000..7211c0e506d
--- /dev/null
+++ b/spec/lib/gitlab/ci/status/preparing_spec.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Ci::Status::Preparing do
+  subject do
+    described_class.new(double('subject'), nil)
+  end
+
+  describe '#text' do
+    it { expect(subject.text).to eq 'preparing' }
+  end
+
+  describe '#label' do
+    it { expect(subject.label).to eq 'preparing' }
+  end
+
+  describe '#icon' do
+    it { expect(subject.icon).to eq 'status_created' }
+  end
+
+  describe '#favicon' do
+    it { expect(subject.favicon).to eq 'favicon_status_created' }
+  end
+
+  describe '#group' do
+    it { expect(subject.group).to eq 'preparing' }
+  end
+end
diff --git a/spec/models/ci/build_spec.rb b/spec/models/ci/build_spec.rb
index 9ca4241d7d8..7500e6ae5b1 100644
--- a/spec/models/ci/build_spec.rb
+++ b/spec/models/ci/build_spec.rb
@@ -186,6 +186,37 @@ describe Ci::Build do
     end
   end
 
+  describe '#enqueue' do
+    let(:build) { create(:ci_build, :created) }
+
+    subject { build.enqueue }
+
+    before do
+      allow(build).to receive(:any_unmet_prerequisites?).and_return(has_prerequisites)
+      allow(Ci::PrepareBuildService).to receive(:perform_async)
+    end
+
+    context 'build has unmet prerequisites' do
+      let(:has_prerequisites) { true }
+
+      it 'transitions to preparing' do
+        subject
+
+        expect(build).to be_preparing
+      end
+    end
+
+    context 'build has no prerequisites' do
+      let(:has_prerequisites) { false }
+
+      it 'transitions to pending' do
+        subject
+
+        expect(build).to be_pending
+      end
+    end
+  end
+
   describe '#actionize' do
     context 'when build is a created' do
       before do
@@ -344,6 +375,18 @@ describe Ci::Build do
 
         expect(build).to be_pending
       end
+
+      context 'build has unmet prerequisites' do
+        before do
+          allow(build).to receive(:prerequisites).and_return([double])
+        end
+
+        it 'transits to preparing' do
+          subject
+
+          expect(build).to be_preparing
+        end
+      end
     end
   end
 
@@ -2876,6 +2919,36 @@ describe Ci::Build do
     end
   end
 
+  describe '#any_unmet_prerequisites?' do
+    let(:build) { create(:ci_build, :created) }
+
+    subject { build.any_unmet_prerequisites? }
+
+    context 'build has prerequisites' do
+      before do
+        allow(build).to receive(:prerequisites).and_return([double])
+      end
+
+      it { is_expected.to be_truthy }
+
+      context 'and the ci_preparing_state feature is disabled' do
+        before do
+          stub_feature_flags(ci_preparing_state: false)
+        end
+
+        it { is_expected.to be_falsey }
+      end
+    end
+
+    context 'build does not have prerequisites' do
+      before do
+        allow(build).to receive(:prerequisites).and_return([])
+      end
+
+      it { is_expected.to be_falsey }
+    end
+  end
+
   describe '#yaml_variables' do
     let(:build) { create(:ci_build, pipeline: pipeline, yaml_variables: variables) }
 
@@ -2928,6 +3001,20 @@ describe Ci::Build do
     end
   end
 
+  describe 'state transition: any => [:preparing]' do
+    let(:build) { create(:ci_build, :created) }
+
+    before do
+      allow(build).to receive(:prerequisites).and_return([double])
+    end
+
+    it 'queues BuildPrepareWorker' do
+      expect(Ci::BuildPrepareWorker).to receive(:perform_async).with(build.id)
+
+      build.enqueue
+    end
+  end
+
   describe 'state transition: any => [:pending]' do
     let(:build) { create(:ci_build, :created) }
 
diff --git a/spec/models/ci/pipeline_spec.rb b/spec/models/ci/pipeline_spec.rb
index 7eeaa7a18ef..2ac056f63b2 100644
--- a/spec/models/ci/pipeline_spec.rb
+++ b/spec/models/ci/pipeline_spec.rb
@@ -1201,16 +1201,28 @@ describe Ci::Pipeline, :mailer do
     end
 
     describe '#started_at' do
-      it 'updates on transitioning to running' do
-        build.run
+      let(:pipeline) { create(:ci_empty_pipeline, status: from_status) }
+
+      %i[created preparing pending].each do |status|
+        context "from #{status}" do
+          let(:from_status) { status }
 
-        expect(pipeline.reload.started_at).not_to be_nil
+          it 'updates on transitioning to running' do
+            pipeline.run
+
+            expect(pipeline.started_at).not_to be_nil
+          end
+        end
       end
 
-      it 'does not update on transitioning to success' do
-        build.success
+      context 'from created' do
+        let(:from_status) { :created }
+
+        it 'does not update on transitioning to success' do
+          pipeline.succeed
 
-        expect(pipeline.reload.started_at).to be_nil
+          expect(pipeline.started_at).to be_nil
+        end
       end
     end
 
@@ -1229,27 +1241,49 @@ describe Ci::Pipeline, :mailer do
     end
 
     describe 'merge request metrics' do
-      let(:project) { create(:project, :repository) }
-      let(:pipeline) { FactoryBot.create(:ci_empty_pipeline, status: 'created', project: project, ref: 'master', sha: project.repository.commit('master').id) }
-      let!(:merge_request) { create(:merge_request, source_project: project, source_branch: pipeline.ref) }
+      let(:pipeline) { create(:ci_empty_pipeline, status: from_status) }
 
       before do
         expect(PipelineMetricsWorker).to receive(:perform_async).with(pipeline.id)
       end
 
       context 'when transitioning to running' do
-        it 'schedules metrics workers' do
-          pipeline.run
+        %i[created preparing pending].each do |status|
+          context "from #{status}" do
+            let(:from_status) { status }
+
+            it 'schedules metrics workers' do
+              pipeline.run
+            end
+          end
         end
       end
 
       context 'when transitioning to success' do
+        let(:from_status) { 'created' }
+
         it 'schedules metrics workers' do
           pipeline.succeed
         end
       end
     end
 
+    describe 'merge on success' do
+      let(:pipeline) { create(:ci_empty_pipeline, status: from_status) }
+
+      %i[created preparing pending running].each do |status|
+        context "from #{status}" do
+          let(:from_status) { status }
+
+          it 'schedules pipeline success worker' do
+            expect(PipelineSuccessWorker).to receive(:perform_async).with(pipeline.id)
+
+            pipeline.succeed
+          end
+        end
+      end
+    end
+
     describe 'pipeline caching' do
       it 'performs ExpirePipelinesCacheWorker' do
         expect(ExpirePipelineCacheWorker).to receive(:perform_async).with(pipeline.id)
@@ -1768,6 +1802,18 @@ describe Ci::Pipeline, :mailer do
 
     subject { pipeline.reload.status }
 
+    context 'on prepare' do
+      before do
+        # Prevent skipping directly to 'pending'
+        allow(build).to receive(:prerequisites).and_return([double])
+        allow(Ci::BuildPrepareWorker).to receive(:perform_async)
+
+        build.enqueue
+      end
+
+      it { is_expected.to eq('preparing') }
+    end
+
     context 'on queuing' do
       before do
         build.enqueue
diff --git a/spec/models/commit_status_spec.rb b/spec/models/commit_status_spec.rb
index 8b7c88805c1..e2b7f5c6ee2 100644
--- a/spec/models/commit_status_spec.rb
+++ b/spec/models/commit_status_spec.rb
@@ -49,6 +49,16 @@ describe CommitStatus do
 
       commit_status.success!
     end
+
+    describe 'transitioning to running' do
+      let(:commit_status) { create(:commit_status, :pending, started_at: nil) }
+
+      it 'records the started at time' do
+        commit_status.run!
+
+        expect(commit_status.started_at).to be_present
+      end
+    end
   end
 
   describe '#started?' do
@@ -479,6 +489,12 @@ describe CommitStatus do
 
       it { is_expected.to be_script_failure }
     end
+
+    context 'when failure_reason is unmet_prerequisites' do
+      let(:reason) { :unmet_prerequisites }
+
+      it { is_expected.to be_unmet_prerequisites }
+    end
   end
 
   describe 'ensure stage assignment' do
@@ -555,6 +571,7 @@ describe CommitStatus do
 
     before do
       allow(Time).to receive(:now).and_return(current_time)
+      expect(commit_status.any_unmet_prerequisites?).to eq false
     end
 
     shared_examples 'commit status enqueued' do
@@ -569,6 +586,12 @@ describe CommitStatus do
       it_behaves_like 'commit status enqueued'
     end
 
+    context 'when initial state is :preparing' do
+      let(:commit_status) { create(:commit_status, :preparing) }
+
+      it_behaves_like 'commit status enqueued'
+    end
+
     context 'when initial state is :skipped' do
       let(:commit_status) { create(:commit_status, :skipped) }
 
diff --git a/spec/models/concerns/has_status_spec.rb b/spec/models/concerns/has_status_spec.rb
index 6b1038cb8fd..e8b1eba67cc 100644
--- a/spec/models/concerns/has_status_spec.rb
+++ b/spec/models/concerns/has_status_spec.rb
@@ -34,6 +34,22 @@ describe HasStatus do
         it { is_expected.to eq 'running' }
       end
 
+      context 'all preparing' do
+        let!(:statuses) do
+          [create(type, status: :preparing), create(type, status: :preparing)]
+        end
+
+        it { is_expected.to eq 'preparing' }
+      end
+
+      context 'at least one preparing' do
+        let!(:statuses) do
+          [create(type, status: :success), create(type, status: :preparing)]
+        end
+
+        it { is_expected.to eq 'preparing' }
+      end
+
       context 'success and failed but allowed to fail' do
         let!(:statuses) do
           [create(type, status: :success),
@@ -188,7 +204,7 @@ describe HasStatus do
       end
     end
 
-    %i[created running pending success
+    %i[created preparing running pending success
        failed canceled skipped].each do |status|
       it_behaves_like 'having a job', status
     end
@@ -234,7 +250,7 @@ describe HasStatus do
     describe '.alive' do
       subject { CommitStatus.alive }
 
-      %i[running pending created].each do |status|
+      %i[running pending preparing created].each do |status|
         it_behaves_like 'containing the job', status
       end
 
@@ -270,7 +286,7 @@ describe HasStatus do
     describe '.cancelable' do
       subject { CommitStatus.cancelable }
 
-      %i[running pending created scheduled].each do |status|
+      %i[running pending preparing created scheduled].each do |status|
         it_behaves_like 'containing the job', status
       end
 
diff --git a/spec/models/deployment_spec.rb b/spec/models/deployment_spec.rb
index a8d53cfcd7d..5fce9504334 100644
--- a/spec/models/deployment_spec.rb
+++ b/spec/models/deployment_spec.rb
@@ -356,4 +356,32 @@ describe Deployment do
       end
     end
   end
+
+  describe '#cluster' do
+    let(:deployment) { create(:deployment) }
+    let(:project) { deployment.project }
+    let(:environment) { deployment.environment }
+
+    subject { deployment.cluster }
+
+    before do
+      expect(project).to receive(:deployment_platform)
+        .with(environment: environment.name).and_call_original
+    end
+
+    context 'project has no deployment platform' do
+      before do
+        expect(project.clusters).to be_empty
+      end
+
+      it { is_expected.to be_nil }
+    end
+
+    context 'project has a deployment platform' do
+      let!(:cluster) { create(:cluster, projects: [project]) }
+      let!(:platform) { create(:cluster_platform_kubernetes, cluster: cluster) }
+
+      it { is_expected.to eq cluster }
+    end
+  end
 end
diff --git a/spec/requests/api/project_clusters_spec.rb b/spec/requests/api/project_clusters_spec.rb
index 9bab1f95150..4e42e233b4c 100644
--- a/spec/requests/api/project_clusters_spec.rb
+++ b/spec/requests/api/project_clusters_spec.rb
@@ -331,7 +331,6 @@ describe API::ProjectClusters do
 
         it 'should update cluster attributes' do
           expect(cluster.platform_kubernetes.namespace).to eq('new-namespace')
-          expect(cluster.kubernetes_namespace.namespace).to eq('new-namespace')
         end
       end
 
diff --git a/spec/requests/api/runner_spec.rb b/spec/requests/api/runner_spec.rb
index 9087cccb759..3ccedd8dd06 100644
--- a/spec/requests/api/runner_spec.rb
+++ b/spec/requests/api/runner_spec.rb
@@ -918,6 +918,15 @@ describe API::Runner, :clean_gitlab_redis_shared_state do
 
           it { expect(job).to be_job_execution_timeout }
         end
+
+        context 'when failure_reason is unmet_prerequisites' do
+          before do
+            update_job(state: 'failed', failure_reason: 'unmet_prerequisites')
+            job.reload
+          end
+
+          it { expect(job).to be_unmet_prerequisites }
+        end
       end
 
       context 'when trace is given' do
diff --git a/spec/services/ci/prepare_build_service_spec.rb b/spec/services/ci/prepare_build_service_spec.rb
new file mode 100644
index 00000000000..1797f8f964f
--- /dev/null
+++ b/spec/services/ci/prepare_build_service_spec.rb
@@ -0,0 +1,54 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Ci::PrepareBuildService do
+  describe '#execute' do
+    let(:build) { create(:ci_build, :preparing) }
+
+    subject { described_class.new(build).execute }
+
+    before do
+      allow(build).to receive(:prerequisites).and_return(prerequisites)
+    end
+
+    shared_examples 'build enqueueing' do
+      it 'enqueues the build' do
+        expect(build).to receive(:enqueue).once
+
+        subject
+      end
+    end
+
+    context 'build has unmet prerequisites' do
+      let(:prerequisite) { double(complete!: true) }
+      let(:prerequisites) { [prerequisite] }
+
+      it 'completes each prerequisite' do
+        expect(prerequisites).to all(receive(:complete!))
+
+        subject
+      end
+
+      include_examples 'build enqueueing'
+
+      context 'prerequisites fail to complete' do
+        before do
+          allow(build).to receive(:enqueue).and_return(false)
+        end
+
+        it 'drops the build' do
+          expect(build).to receive(:drop!).with(:unmet_prerequisites).once
+
+          subject
+        end
+      end
+    end
+
+    context 'build has no prerequisites' do
+      let(:prerequisites) { [] }
+
+      include_examples 'build enqueueing'
+    end
+  end
+end
diff --git a/spec/services/projects/create_service_spec.rb b/spec/services/projects/create_service_spec.rb
index d1b110b9806..e8418b09dc2 100644
--- a/spec/services/projects/create_service_spec.rb
+++ b/spec/services/projects/create_service_spec.rb
@@ -276,6 +276,7 @@ describe Projects::CreateService, '#execute' do
     before do
       group.add_owner(user)
 
+      stub_feature_flags(ci_preparing_state: false)
       expect(Clusters::Gcp::Kubernetes::CreateOrUpdateServiceAccountService).to receive(:namespace_creator).and_return(service_account_creator)
       expect(Clusters::Gcp::Kubernetes::FetchKubernetesTokenService).to receive(:new).and_return(secrets_fetcher)
     end
diff --git a/spec/services/projects/transfer_service_spec.rb b/spec/services/projects/transfer_service_spec.rb
index aae50d5307f..4efd360cb30 100644
--- a/spec/services/projects/transfer_service_spec.rb
+++ b/spec/services/projects/transfer_service_spec.rb
@@ -83,6 +83,7 @@ describe Projects::TransferService do
       subject { transfer_project(project, user, group) }
 
       before do
+        stub_feature_flags(ci_preparing_state: false)
         expect(Clusters::Gcp::Kubernetes::CreateOrUpdateServiceAccountService).to receive(:namespace_creator).and_return(service_account_creator)
         expect(Clusters::Gcp::Kubernetes::FetchKubernetesTokenService).to receive(:new).and_return(secrets_fetcher)
       end
diff --git a/spec/workers/ci/build_prepare_worker_spec.rb b/spec/workers/ci/build_prepare_worker_spec.rb
new file mode 100644
index 00000000000..9f76696ee66
--- /dev/null
+++ b/spec/workers/ci/build_prepare_worker_spec.rb
@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Ci::BuildPrepareWorker do
+  subject { described_class.new.perform(build_id) }
+
+  context 'build exists' do
+    let(:build) { create(:ci_build) }
+    let(:build_id) { build.id }
+    let(:service) { double(execute: true) }
+
+    it 'calls the prepare build service' do
+      expect(Ci::PrepareBuildService).to receive(:new).with(build).and_return(service)
+      expect(service).to receive(:execute).once
+
+      subject
+    end
+  end
+
+  context 'build does not exist' do
+    let(:build_id) { -1 }
+
+    it 'does not attempt to prepare the build' do
+      expect(Ci::PrepareBuildService).not_to receive(:new)
+
+      subject
+    end
+  end
+end
diff --git a/spec/workers/cluster_configure_worker_spec.rb b/spec/workers/cluster_configure_worker_spec.rb
index 6918ee3d7d8..83f76809435 100644
--- a/spec/workers/cluster_configure_worker_spec.rb
+++ b/spec/workers/cluster_configure_worker_spec.rb
@@ -4,6 +4,11 @@ require 'spec_helper'
 
 describe ClusterConfigureWorker, '#perform' do
   let(:worker) { described_class.new }
+  let(:ci_preparing_state_enabled) { false }
+
+  before do
+    stub_feature_flags(ci_preparing_state: ci_preparing_state_enabled)
+  end
 
   context 'when group cluster' do
     let(:cluster) { create(:cluster, :group, :provided_by_gcp) }
@@ -66,4 +71,15 @@ describe ClusterConfigureWorker, '#perform' do
       described_class.new.perform(123)
     end
   end
+
+  context 'ci_preparing_state feature is enabled' do
+    let(:cluster) { create(:cluster) }
+    let(:ci_preparing_state_enabled) { true }
+
+    it 'does not configure the cluster' do
+      expect(Clusters::RefreshService).not_to receive(:create_or_update_namespaces_for_cluster)
+
+      described_class.new.perform(cluster.id)
+    end
+  end
 end
diff --git a/spec/workers/cluster_project_configure_worker_spec.rb b/spec/workers/cluster_project_configure_worker_spec.rb
new file mode 100644
index 00000000000..afdea55adf4
--- /dev/null
+++ b/spec/workers/cluster_project_configure_worker_spec.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe ClusterProjectConfigureWorker, '#perform' do
+  let(:worker) { described_class.new }
+
+  context 'ci_preparing_state feature is enabled' do
+    let(:cluster) { create(:cluster) }
+
+    before do
+      stub_feature_flags(ci_preparing_state: true)
+    end
+
+    it 'does not configure the cluster' do
+      expect(Clusters::RefreshService).not_to receive(:create_or_update_namespaces_for_project)
+
+      described_class.new.perform(cluster.id)
+    end
+  end
+end