Merge branch '38668-revert-copied-kubernetesservice-logic' into 'master'

Copy `KubernetesService` logic in `Clusters::Platforms::Kubernetes` to make it interchangeable. And implement a selector.

See merge request gitlab-org/gitlab-ce!15515

app/controllers/projects/branches_controller.rb

@@ -41,7 +41,7 @@ class Projects::BranchesController < Projects::ApplicationController
     branch_name = sanitize(strip_tags(params[:branch_name]))
     branch_name = Addressable::URI.unescape(branch_name)
 
-    redirect_to_autodeploy = project.empty_repo? && project.deployment_services.present?
+    redirect_to_autodeploy = project.empty_repo? && project.deployment_platform.present?
 
     result = CreateBranchService.new(project, current_user)
         .execute(branch_name, ref)

app/helpers/auto_devops_helper.rb

@@ -26,7 +26,7 @@ module AutoDevopsHelper
 
   def auto_devops_warning_message(project)
     missing_domain = !project.auto_devops&.has_domain?
-    missing_service = !project.kubernetes_service&.active?
+    missing_service = !project.deployment_platform&.active?
 
     if missing_service
       params = {

app/models/ci/pipeline.rb

@@ -365,7 +365,7 @@ module Ci
     end
 
     def has_kubernetes_active?
-      project.kubernetes_service&.active?
+      project.deployment_platform&.active?
     end
 
     def has_stage_seeds?

app/models/clusters/cluster.rb

@@ -17,8 +17,7 @@ module Clusters
     # we force autosave to happen when we save `Cluster` model
     has_one :provider_gcp, class_name: 'Clusters::Providers::Gcp', autosave: true
 
-    # We have to ":destroy" it today to ensure that we clean also the Kubernetes Integration
+    has_one :platform_kubernetes, class_name: 'Clusters::Platforms::Kubernetes'
-    has_one :platform_kubernetes, class_name: 'Clusters::Platforms::Kubernetes', autosave: true, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
     has_one :application_helm, class_name: 'Clusters::Applications::Helm'
     has_one :application_ingress, class_name: 'Clusters::Applications::Ingress'
@@ -29,15 +28,9 @@ module Clusters
     validates :name, cluster_name: true
     validate :restrict_modification, on: :update
 
-    # TODO: Move back this into Clusters::Platforms::Kubernetes in 10.3
-    # We need callback here because `enabled` belongs to Clusters::Cluster
-    # Callbacks in Clusters::Platforms::Kubernetes will not be called after update
-    after_save :update_kubernetes_integration!
-
     delegate :status, to: :provider, allow_nil: true
     delegate :status_reason, to: :provider, allow_nil: true
     delegate :on_creation?, to: :provider, allow_nil: true
-    delegate :update_kubernetes_integration!, to: :platform, allow_nil: true
 
     delegate :active?, to: :platform_kubernetes, prefix: true, allow_nil: true
     delegate :installed?, to: :application_helm, prefix: true, allow_nil: true

app/models/clusters/platforms/kubernetes.rb

@@ -1,7 +1,12 @@
 module Clusters
   module Platforms
     class Kubernetes < ActiveRecord::Base
+      include Gitlab::CurrentSettings
+      include Gitlab::Kubernetes
+      include ReactiveCaching
+
       self.table_name = 'cluster_platforms_kubernetes'
+      self.reactive_cache_key = ->(kubernetes) { [kubernetes.class.model_name.singular, kubernetes.id] }
 
       belongs_to :cluster, inverse_of: :platform_kubernetes, class_name: 'Clusters::Cluster'
 
@@ -29,19 +34,14 @@ module Clusters
       validates :api_url, url: true, presence: true
       validates :token, presence: true
 
-      # TODO: Glue code till we migrate Kubernetes Integration into Platforms::Kubernetes
+      after_save :clear_reactive_cache!
-      after_destroy :destroy_kubernetes_integration!
 
       alias_attribute :ca_pem, :ca_cert
 
       delegate :project, to: :cluster, allow_nil: true
       delegate :enabled?, to: :cluster, allow_nil: true
 
-      class << self
+      alias_method :active?, :enabled?
-        def namespace_for_project(project)
-          "#{project.path}-#{project.id}"
-        end
-      end
 
       def actual_namespace
         if namespace.present?
@@ -51,59 +51,128 @@ module Clusters
         end
       end
 
-      def default_namespace
+      def predefined_variables
-        self.class.namespace_for_project(project) if project
+        config = YAML.dump(kubeconfig)
+
+        variables = [
+          { key: 'KUBE_URL', value: api_url, public: true },
+          { key: 'KUBE_TOKEN', value: token, public: false },
+          { key: 'KUBE_NAMESPACE', value: actual_namespace, public: true },
+          { key: 'KUBECONFIG', value: config, public: false, file: true }
+        ]
+
+        if ca_pem.present?
+          variables << { key: 'KUBE_CA_PEM', value: ca_pem, public: true }
+          variables << { key: 'KUBE_CA_PEM_FILE', value: ca_pem, public: true, file: true }
+        end
+
+        variables
+      end
+
+      # Constructs a list of terminals from the reactive cache
+      #
+      # Returns nil if the cache is empty, in which case you should try again a
+      # short time later
+      def terminals(environment)
+        with_reactive_cache do |data|
+          pods = filter_by_label(data[:pods], app: environment.slug)
+          terminals = pods.flat_map { |pod| terminals_for_pod(api_url, actual_namespace, pod) }
+          terminals.each { |terminal| add_terminal_auth(terminal, terminal_auth) }
+        end
+      end
+
+      # Caches resources in the namespace so other calls don't need to block on
+      # network access
+      def calculate_reactive_cache
+        return unless enabled? && project && !project.pending_delete?
+
+        # We may want to cache extra things in the future
+        { pods: read_pods }
       end
 
       def kubeclient
-        @kubeclient ||= kubernetes_service.kubeclient if manages_kubernetes_service?
+        @kubeclient ||= build_kubeclient!
-      end
-
-      def update_kubernetes_integration!
-        raise 'Kubernetes service already configured' unless manages_kubernetes_service?
-
-        # This is neccesary, otheriwse enabled? returns true even though cluster updated with enabled: false
-        cluster.reload
-
-        ensure_kubernetes_service&.update!(
-          active: enabled?,
-          api_url: api_url,
-          namespace: namespace,
-          token: token,
-          ca_pem: ca_cert
-        )
-      end
-
-      def active?
-        manages_kubernetes_service?
       end
 
       private
 
+      def kubeconfig
+        to_kubeconfig(
+          url: api_url,
+          namespace: actual_namespace,
+          token: token,
+          ca_pem: ca_pem)
+      end
+
+      def default_namespace
+        return unless project
+
+        slug = "#{project.path}-#{project.id}".downcase
+        slug.gsub(/[^-a-z0-9]/, '-').gsub(/^-+/, '')
+      end
+
+      def build_kubeclient!(api_path: 'api', api_version: 'v1')
+        raise "Incomplete settings" unless api_url && actual_namespace
+
+        unless (username && password) || token
+          raise "Either username/password or token is required to access API"
+        end
+
+        ::Kubeclient::Client.new(
+          join_api_url(api_path),
+          api_version,
+          auth_options: kubeclient_auth_options,
+          ssl_options: kubeclient_ssl_options,
+          http_proxy_uri: ENV['http_proxy']
+        )
+      end
+
+      # Returns a hash of all pods in the namespace
+      def read_pods
+        kubeclient = build_kubeclient!
+
+        kubeclient.get_pods(namespace: actual_namespace).as_json
+      rescue KubeException => err
+        raise err unless err.error_code == 404
+
+        []
+      end
+
+      def kubeclient_ssl_options
+        opts = { verify_ssl: OpenSSL::SSL::VERIFY_PEER }
+
+        if ca_pem.present?
+          opts[:cert_store] = OpenSSL::X509::Store.new
+          opts[:cert_store].add_cert(OpenSSL::X509::Certificate.new(ca_pem))
+        end
+
+        opts
+      end
+
+      def kubeclient_auth_options
+        { bearer_token: token }
+      end
+
+      def join_api_url(api_path)
+        url = URI.parse(api_url)
+        prefix = url.path.sub(%r{/+\z}, '')
+
+        url.path = [prefix, api_path].join("/")
+
+        url.to_s
+      end
+
+      def terminal_auth
+        {
+          token: token,
+          ca_pem: ca_pem,
+          max_session_time: current_application_settings.terminal_max_session_time
+        }
+      end
+
       def enforce_namespace_to_lower_case
         self.namespace = self.namespace&.downcase
       end
-
-      # TODO: glue code till we migrate Kubernetes Service into Platforms::Kubernetes class
-      def manages_kubernetes_service?
-        return true unless kubernetes_service&.active?
-
-        kubernetes_service.api_url == api_url
-      end
-
-      def destroy_kubernetes_integration!
-        return unless manages_kubernetes_service?
-
-        kubernetes_service&.destroy!
-      end
-
-      def kubernetes_service
-        @kubernetes_service ||= project&.kubernetes_service
-      end
-
-      def ensure_kubernetes_service
-        @kubernetes_service ||= kubernetes_service || project&.build_kubernetes_service
-      end
     end
   end
 end

app/models/environment.rb

@@ -138,11 +138,11 @@ class Environment < ActiveRecord::Base
   end
 
   def has_terminals?
-    project.deployment_service.present? && available? && last_deployment.present?
+    project.deployment_platform.present? && available? && last_deployment.present?
   end
 
   def terminals
-    project.deployment_service.terminals(self) if has_terminals?
+    project.deployment_platform.terminals(self) if has_terminals?
   end
 
   def has_metrics?

app/models/project.rb

@@ -897,12 +897,10 @@ class Project < ActiveRecord::Base
     @ci_service ||= ci_services.reorder(nil).find_by(active: true)
   end
 
-  def deployment_services
+  # TODO: This will be extended for multiple enviroment clusters
-    services.where(category: :deployment)
+  def deployment_platform
-  end
+    @deployment_platform ||= clusters.find_by(enabled: true)&.platform_kubernetes
-
+    @deployment_platform ||= services.where(category: :deployment).reorder(nil).find_by(active: true)
-  def deployment_service
-    @deployment_service ||= deployment_services.reorder(nil).find_by(active: true)
   end
 
   def monitoring_services
@@ -1547,9 +1545,9 @@ class Project < ActiveRecord::Base
   end
 
   def deployment_variables
-    return [] unless deployment_service
+    return [] unless deployment_platform
 
-    deployment_service.predefined_variables
+    deployment_platform.predefined_variables
   end
 
   def auto_devops_variables

app/models/project_services/kubernetes_service.rb

@@ -1,3 +1,8 @@
+##
+# NOTE:
+# We'll move this class to Clusters::Platforms::Kubernetes, which contains exactly the same logic.
+# After we've migrated data, we'll remove KubernetesService. This would happen in a few months.
+# If you're modyfiyng this class, please note that you should update the same change in Clusters::Platforms::Kubernetes.
 class KubernetesService < DeploymentService
   include Gitlab::CurrentSettings
   include Gitlab::Kubernetes

app/views/projects/clusters/new.html.haml

@@ -5,7 +5,7 @@
   .col-sm-4
     = render 'sidebar'
   .col-sm-8
-    - if @project.kubernetes_service&.active?
+    - if @project.deployment_platform&.active?
       %h4.prepend-top-0= s_('ClusterIntegration|Cluster management')
 
       %p= s_('ClusterIntegration|A cluster has been set up on this project through the Kubernetes integration page')

app/views/projects/edit.html.haml

@@ -147,7 +147,7 @@
             %ul
               %li Be careful. Renaming a project's repository can have unintended side effects.
               %li You will need to update your local repositories to point to the new location.
-              - if @project.deployment_services.any?
+              - if @project.deployment_platform.present?
                 %li Your deployment services will be broken, you will need to manually fix the services after renaming.
           = f.submit 'Rename project', class: "btn btn-warning"
       - if can?(current_user, :change_namespace, @project)

app/views/projects/show.html.haml

@@ -67,7 +67,7 @@
         - if koding_enabled? && @repository.koding_yml.blank?
           %li.missing
             = link_to  _('Set up Koding'), add_koding_stack_path(@project)
-        - if @repository.gitlab_ci_yml.blank? && @project.deployment_service.present?
+        - if @repository.gitlab_ci_yml.blank? && @project.deployment_platform.present?
           %li.missing
             = link_to add_special_file_path(@project, file_name: '.gitlab-ci.yml', commit_message: 'Set up auto deploy', branch_name: 'auto-deploy', context: 'autodeploy') do
               #{ _('Set up auto deploy') }

lib/gitlab/prometheus/queries/query_additional_metrics.rb

@@ -76,7 +76,7 @@ module Gitlab
             timeframe_start: timeframe_start,
             timeframe_end: timeframe_end,
             ci_environment_slug: environment.slug,
-            kube_namespace: environment.project.kubernetes_service&.actual_namespace || '',
+            kube_namespace: environment.project.deployment_platform&.actual_namespace || '',
             environment_filter: %{container_name!="POD",environment="#{environment.slug}"}
           }
         end

spec/controllers/projects/branches_controller_spec.rb

@@ -113,11 +113,10 @@ describe Projects::BranchesController do
           expect(response).to redirect_to project_tree_path(project, branch)
         end
 
+        shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
           it 'redirects to autodeploy setup page' do
             result = { status: :success, branch: double(name: branch) }
 
-          project.services << build(:kubernetes_service)
-
             expect_any_instance_of(CreateBranchService).to receive(:execute).and_return(result)
             expect(SystemNoteService).to receive(:new_issue_branch).and_return(true)
 
@@ -132,6 +131,23 @@ describe Projects::BranchesController do
           end
         end
 
+        context 'when user configured kubernetes from Integration > Kubernetes' do
+          before do
+            project.services << build(:kubernetes_service)
+          end
+
+          it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+        end
+
+        context 'when user configured kubernetes from CI/CD > Clusters' do
+          before do
+            create(:cluster, :provided_by_gcp, projects: [project])
+          end
+
+          it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+        end
+      end
+
       context 'without issue feature access' do
         before do
           project.update!(visibility_level: Gitlab::VisibilityLevel::PUBLIC)

spec/features/auto_deploy_spec.rb

@@ -4,15 +4,10 @@ describe 'Auto deploy' do
   let(:user) { create(:user) }
   let(:project) { create(:project, :repository) }
 
-  before do
+  shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
-    create :kubernetes_service, project: project
-    project.team << [user, :master]
-    sign_in user
-  end
-
     context 'when no deployment service is active' do
       before do
-      project.kubernetes_service.update!(active: false)
+        trun_off
       end
 
       it 'does not show a button to set up auto deploy' do
@@ -23,7 +18,7 @@ describe 'Auto deploy' do
 
     context 'when a deployment service is active' do
       before do
-      project.kubernetes_service.update!(active: true)
+        trun_on
         visit project_path(project)
       end
 
@@ -52,4 +47,31 @@ describe 'Auto deploy' do
         expect(page).to have_content('New Merge Request From auto-deploy into master')
       end
     end
+  end
+
+  context 'when user configured kubernetes from Integration > Kubernetes' do
+    before do
+      create :kubernetes_service, project: project
+      project.team << [user, :master]
+      sign_in user
+    end
+
+    let(:trun_on) { project.deployment_platform.update!(active: true) }
+    let(:trun_off) { project.deployment_platform.update!(active: false) }
+
+    it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+  end
+
+  context 'when user configured kubernetes from CI/CD > Clusters' do
+    before do
+      create(:cluster, :provided_by_gcp, projects: [project])
+      project.team << [user, :master]
+      sign_in user
+    end
+
+    let(:trun_on) { project.deployment_platform.cluster.update!(enabled: true) }
+    let(:trun_off) { project.deployment_platform.cluster.update!(enabled: false) }
+
+    it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+  end
 end

spec/features/projects/clusters/interchangeability_spec.rb

@@ -0,0 +1,16 @@
+require 'spec_helper'
+
+feature 'Interchangeability between KubernetesService and Platform::Kubernetes' do
+  EXCEPT_METHODS = %i[test title description help fields initialize_properties namespace namespace= api_url api_url=].freeze
+  EXCEPT_METHODS_GREP_V = %w[_touched? _changed? _was].freeze
+
+  it 'Clusters::Platform::Kubernetes covers core interfaces in KubernetesService' do
+    expected_interfaces = KubernetesService.instance_methods(false)
+    expected_interfaces = expected_interfaces - EXCEPT_METHODS
+    EXCEPT_METHODS_GREP_V.each do |g|
+      expected_interfaces = expected_interfaces.grep_v(/#{Regexp.escape(g)}\z/)
+    end
+
+    expect(expected_interfaces - Clusters::Platforms::Kubernetes.instance_methods).to be_empty
+  end
+end

spec/features/projects/environments/environment_spec.rb

@@ -101,8 +101,7 @@ feature 'Environment' do
           end
 
           context 'with terminal' do
-            let(:project) { create(:kubernetes_project, :test_repo) }
+            shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
-
               context 'for project master' do
                 let(:role) { :master }
 
@@ -133,6 +132,20 @@ feature 'Environment' do
               end
             end
 
+            context 'when user configured kubernetes from Integration > Kubernetes' do
+              let(:project) { create(:kubernetes_project, :test_repo) }
+
+              it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+            end
+
+            context 'when user configured kubernetes from CI/CD > Clusters' do
+              let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
+              let(:project) { cluster.project }
+
+              it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+            end
+          end
+
           context 'when environment is available' do
             context 'with stop action' do
               given(:action) do

spec/features/projects/environments/environments_spec.rb

@@ -208,8 +208,7 @@ feature 'Environments page', :js do
         end
 
         context 'when kubernetes terminal is available' do
-          let(:project) { create(:kubernetes_project, :test_repo) }
+          shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
-
             context 'for project master' do
               let(:role) { :master }
 
@@ -226,6 +225,20 @@ feature 'Environments page', :js do
               end
             end
           end
+
+          context 'when user configured kubernetes from Integration > Kubernetes' do
+            let(:project) { create(:kubernetes_project, :test_repo) }
+
+            it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+          end
+
+          context 'when user configured kubernetes from CI/CD > Clusters' do
+            let(:cluster) { create(:cluster, :provided_by_gcp, projects: [create(:project, :repository)]) }
+            let(:project) { cluster.project }
+
+            it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+          end
+        end
       end
     end
   end

spec/lib/gitlab/ci/build/policy/kubernetes_spec.rb

@@ -4,14 +4,27 @@ describe Gitlab::Ci::Build::Policy::Kubernetes do
   let(:pipeline) { create(:ci_pipeline, project: project) }
 
   context 'when kubernetes service is active' do
-    set(:project) { create(:kubernetes_project) }
+    shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
-
       it 'is satisfied by a kubernetes pipeline' do
         expect(described_class.new('active'))
           .to be_satisfied_by(pipeline)
       end
     end
 
+    context 'when user configured kubernetes from Integration > Kubernetes' do
+      let(:project) { create(:kubernetes_project) }
+
+      it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+    end
+
+    context 'when user configured kubernetes from CI/CD > Clusters' do
+      let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
+      let(:project) { cluster.project }
+
+      it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+    end
+  end
+
   context 'when kubernetes service is inactive' do
     set(:project) { create(:project) }
 

spec/lib/gitlab/ci/yaml_processor_spec.rb

@@ -178,9 +178,7 @@ module Gitlab
           end
 
           context 'when kubernetes is active' do
-            let(:project) { create(:kubernetes_project) }
+            shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
-            let(:pipeline) { create(:ci_empty_pipeline, project: project) }
-
               it 'returns seeds for kubernetes dependent job' do
                 seeds = subject.stage_seeds(pipeline)
 
@@ -190,6 +188,22 @@ module Gitlab
               end
             end
 
+            context 'when user configured kubernetes from Integration > Kubernetes' do
+              let(:project) { create(:kubernetes_project) }
+              let(:pipeline) { create(:ci_empty_pipeline, project: project) }
+
+              it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+            end
+
+            context 'when user configured kubernetes from CI/CD > Clusters' do
+              let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
+              let(:project) { cluster.project }
+              let(:pipeline) { create(:ci_empty_pipeline, project: project) }
+
+              it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+            end
+          end
+
           context 'when kubernetes is not active' do
             it 'does not return seeds for kubernetes dependent job' do
               seeds = subject.stage_seeds(pipeline)

spec/models/ci/pipeline_spec.rb

@@ -557,13 +557,26 @@ describe Ci::Pipeline, :mailer do
 
   describe '#has_kubernetes_active?' do
     context 'when kubernetes is active' do
-      let(:project) { create(:kubernetes_project) }
+      shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
-
         it 'returns true' do
           expect(pipeline).to have_kubernetes_active
         end
       end
 
+      context 'when user configured kubernetes from Integration > Kubernetes' do
+        let(:project) { create(:kubernetes_project) }
+
+        it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+      end
+
+      context 'when user configured kubernetes from CI/CD > Clusters' do
+        let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
+        let(:project) { cluster.project }
+
+        it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+      end
+    end
+
     context 'when kubernetes is not active' do
       it 'returns false' do
         expect(pipeline).not_to have_kubernetes_active

spec/models/clusters/cluster_spec.rb

@@ -9,7 +9,6 @@ describe Clusters::Cluster do
   it { is_expected.to delegate_method(:status_reason).to(:provider) }
   it { is_expected.to delegate_method(:status_name).to(:provider) }
   it { is_expected.to delegate_method(:on_creation?).to(:provider) }
-  it { is_expected.to delegate_method(:update_kubernetes_integration!).to(:platform) }
   it { is_expected.to respond_to :project }
 
   describe '.enabled' do

spec/models/clusters/platforms/kubernetes_spec.rb

@@ -5,6 +5,8 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
   include ReactiveCachingHelpers
 
   it { is_expected.to belong_to(:cluster) }
+  it { is_expected.to be_kind_of(Gitlab::Kubernetes) }
+  it { is_expected.to be_kind_of(ReactiveCaching) }
   it { is_expected.to respond_to :ca_pem }
 
   describe 'before_validation' do
@@ -90,55 +92,6 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
     end
   end
 
-  describe 'after_save from Clusters::Cluster' do
-    context 'when platform_kubernetes is being cerated' do
-      let(:enabled) { true }
-      let(:project) { create(:project) }
-      let(:cluster) { build(:cluster, provider_type: :gcp, platform_type: :kubernetes, platform_kubernetes: platform, provider_gcp: provider, enabled: enabled, projects: [project]) }
-      let(:platform) { build(:cluster_platform_kubernetes, :configured) }
-      let(:provider) { build(:cluster_provider_gcp) }
-      let(:kubernetes_service) { project.kubernetes_service }
-
-      it 'updates KubernetesService' do
-        cluster.save!
-
-        expect(kubernetes_service.active).to eq(enabled)
-        expect(kubernetes_service.api_url).to eq(platform.api_url)
-        expect(kubernetes_service.namespace).to eq(platform.namespace)
-        expect(kubernetes_service.ca_pem).to eq(platform.ca_cert)
-      end
-    end
-
-    context 'when platform_kubernetes has been created' do
-      let(:enabled) { false }
-      let!(:project) { create(:project) }
-      let!(:cluster) { create(:cluster, :provided_by_gcp, projects: [project]) }
-      let(:platform) { cluster.platform }
-      let(:kubernetes_service) { project.kubernetes_service }
-
-      it 'updates KubernetesService' do
-        cluster.update(enabled: enabled)
-
-        expect(kubernetes_service.active).to eq(enabled)
-      end
-    end
-
-    context 'when kubernetes_service has been configured without cluster integration' do
-      let!(:project) { create(:project) }
-      let(:cluster) { build(:cluster, provider_type: :gcp, platform_type: :kubernetes, platform_kubernetes: platform, provider_gcp: provider, projects: [project]) }
-      let(:platform) { build(:cluster_platform_kubernetes, :configured, api_url: 'https://111.111.111.111') }
-      let(:provider) { build(:cluster_provider_gcp) }
-
-      before do
-        create(:kubernetes_service, project: project)
-      end
-
-      it 'raises an error' do
-        expect { cluster.save! }.to raise_error('Kubernetes service already configured')
-      end
-    end
-  end
-
   describe '#actual_namespace' do
     subject { kubernetes.actual_namespace }
 
@@ -159,16 +112,8 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
     end
   end
 
-  describe '.namespace_for_project' do
-    subject { described_class.namespace_for_project(project) }
-
-    let(:project) { create(:project) }
-
-    it { is_expected.to eq("#{project.path}-#{project.id}") }
-  end
-
   describe '#default_namespace' do
-    subject { kubernetes.default_namespace }
+    subject { kubernetes.send(:default_namespace) }
 
     let(:kubernetes) { create(:cluster_platform_kubernetes, :configured) }
 
@@ -185,4 +130,137 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
       it { is_expected.to be_nil }
     end
   end
+
+  describe '#predefined_variables' do
+    let!(:cluster) { create(:cluster, :project, platform_kubernetes: kubernetes) }
+    let(:kubernetes) { create(:cluster_platform_kubernetes, api_url: api_url, ca_cert: ca_pem, token: token) }
+    let(:api_url) { 'https://kube.domain.com' }
+    let(:ca_pem) { 'CA PEM DATA' }
+    let(:token) { 'token' }
+
+    let(:kubeconfig) do
+      config_file = expand_fixture_path('config/kubeconfig.yml')
+      config = YAML.load(File.read(config_file))
+      config.dig('users', 0, 'user')['token'] = token
+      config.dig('contexts', 0, 'context')['namespace'] = namespace
+      config.dig('clusters', 0, 'cluster')['certificate-authority-data'] =
+        Base64.strict_encode64(ca_pem)
+
+      YAML.dump(config)
+    end
+
+    shared_examples 'setting variables' do
+      it 'sets the variables' do
+        expect(kubernetes.predefined_variables).to include(
+          { key: 'KUBE_URL', value: api_url, public: true },
+          { key: 'KUBE_TOKEN', value: token, public: false },
+          { key: 'KUBE_NAMESPACE', value: namespace, public: true },
+          { key: 'KUBECONFIG', value: kubeconfig, public: false, file: true },
+          { key: 'KUBE_CA_PEM', value: ca_pem, public: true },
+          { key: 'KUBE_CA_PEM_FILE', value: ca_pem, public: true, file: true }
+        )
+      end
+    end
+
+    context 'namespace is provided' do
+      let(:namespace) { 'my-project' }
+
+      before do
+        kubernetes.namespace = namespace
+      end
+
+      it_behaves_like 'setting variables'
+    end
+
+    context 'no namespace provided' do
+      let(:namespace) { kubernetes.actual_namespace }
+
+      it_behaves_like 'setting variables'
+
+      it 'sets the KUBE_NAMESPACE' do
+        kube_namespace = kubernetes.predefined_variables.find { |h| h[:key] == 'KUBE_NAMESPACE' }
+
+        expect(kube_namespace).not_to be_nil
+        expect(kube_namespace[:value]).to match(/\A#{Gitlab::PathRegex::PATH_REGEX_STR}-\d+\z/)
+      end
+    end
+  end
+
+  describe '#terminals' do
+    subject { service.terminals(environment) }
+
+    let!(:cluster) { create(:cluster, :project, platform_kubernetes: service) }
+    let(:project) { cluster.project }
+    let(:service) { create(:cluster_platform_kubernetes, :configured) }
+    let(:environment) { build(:environment, project: project, name: "env", slug: "env-000000") }
+
+    context 'with invalid pods' do
+      it 'returns no terminals' do
+        stub_reactive_cache(service, pods: [{ "bad" => "pod" }])
+
+        is_expected.to be_empty
+      end
+    end
+
+    context 'with valid pods' do
+      let(:pod) { kube_pod(app: environment.slug) }
+      let(:terminals) { kube_terminals(service, pod) }
+
+      before do
+        stub_reactive_cache(
+          service,
+          pods: [pod, pod, kube_pod(app: "should-be-filtered-out")]
+        )
+      end
+
+      it 'returns terminals' do
+        is_expected.to eq(terminals + terminals)
+      end
+
+      it 'uses max session time from settings' do
+        stub_application_setting(terminal_max_session_time: 600)
+
+        times = subject.map { |terminal| terminal[:max_session_time] }
+        expect(times).to eq [600, 600, 600, 600]
+      end
+    end
+  end
+
+  describe '#calculate_reactive_cache' do
+    subject { service.calculate_reactive_cache }
+
+    let!(:cluster) { create(:cluster, :project, enabled: enabled, platform_kubernetes: service) }
+    let(:service) { create(:cluster_platform_kubernetes, :configured) }
+    let(:enabled) { true }
+
+    context 'when cluster is disabled' do
+      let(:enabled) { false }
+
+      it { is_expected.to be_nil }
+    end
+
+    context 'when kubernetes responds with valid pods' do
+      before do
+        stub_kubeclient_pods
+      end
+
+      it { is_expected.to eq(pods: [kube_pod]) }
+    end
+
+    context 'when kubernetes responds with 500s' do
+      before do
+        stub_kubeclient_pods(status: 500)
+      end
+
+      it { expect { subject }.to raise_error(KubeException) }
+    end
+
+    context 'when kubernetes responds with 404s' do
+      before do
+        stub_kubeclient_pods(status: 404)
+      end
+
+      it { is_expected.to eq(pods: []) }
+    end
+  end
 end

spec/models/environment_spec.rb

@@ -327,8 +327,7 @@ describe Environment do
 
     context 'when the enviroment is available' do
       context 'with a deployment service' do
-        let(:project) { create(:kubernetes_project) }
+        shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
-
           context 'and a deployment' do
             let!(:deployment) { create(:deployment, environment: environment) }
             it { is_expected.to be_truthy }
@@ -339,6 +338,20 @@ describe Environment do
           end
         end
 
+        context 'when user configured kubernetes from Integration > Kubernetes' do
+          let(:project) { create(:kubernetes_project) }
+
+          it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+        end
+
+        context 'when user configured kubernetes from CI/CD > Clusters' do
+          let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
+          let(:project) { cluster.project }
+
+          it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+        end
+      end
+
       context 'without a deployment service' do
         it { is_expected.to be_falsy }
       end
@@ -356,7 +369,6 @@ describe Environment do
   end
 
   describe '#terminals' do
-    let(:project) { create(:kubernetes_project) }
     subject { environment.terminals }
 
     context 'when the environment has terminals' do
@@ -364,8 +376,9 @@ describe Environment do
         allow(environment).to receive(:has_terminals?).and_return(true)
       end
 
+      shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
         it 'returns the terminals from the deployment service' do
-        expect(project.deployment_service)
+          expect(project.deployment_platform)
             .to receive(:terminals).with(environment)
             .and_return(:fake_terminals)
 
@@ -373,6 +386,20 @@ describe Environment do
         end
       end
 
+      context 'when user configured kubernetes from Integration > Kubernetes' do
+        let(:project) { create(:kubernetes_project) }
+
+        it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+      end
+
+      context 'when user configured kubernetes from CI/CD > Clusters' do
+        let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
+        let(:project) { cluster.project }
+
+        it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+      end
+    end
+
     context 'when the environment does not have terminals' do
       before do
         allow(environment).to receive(:has_terminals?).and_return(false)

spec/models/project_services/kubernetes_service_spec.rb

@@ -4,8 +4,8 @@ describe KubernetesService, :use_clean_rails_memory_store_caching do
   include KubernetesHelpers
   include ReactiveCachingHelpers
 
-  let(:project) { build_stubbed(:kubernetes_project) }
+  let(:project) { create(:kubernetes_project) }
-  let(:service) { project.kubernetes_service }
+  let(:service) { project.deployment_platform }
 
   describe 'Associations' do
     it { is_expected.to belong_to :project }

spec/models/project_spec.rb

@@ -2002,14 +2002,27 @@ describe Project do
     end
 
     context 'when project has a deployment service' do
-      let(:project) { create(:kubernetes_project) }
+      shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
-
         it 'returns variables from this service' do
           expect(project.deployment_variables).to include(
-          { key: 'KUBE_TOKEN', value: project.kubernetes_service.token, public: false }
+            { key: 'KUBE_TOKEN', value: project.deployment_platform.token, public: false }
           )
         end
       end
+
+      context 'when user configured kubernetes from Integration > Kubernetes' do
+        let(:project) { create(:kubernetes_project) }
+
+        it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+      end
+
+      context 'when user configured kubernetes from CI/CD > Clusters' do
+        let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
+        let(:project) { cluster.project }
+
+        it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+      end
+    end
   end
 
   describe '#secret_variables_for' do
@@ -3083,4 +3096,23 @@ describe Project do
       expect(project.wiki_repository_exists?).to eq(false)
     end
   end
+
+  describe '#deployment_platform' do
+    subject { project.deployment_platform }
+
+    let(:project) { create(:project) }
+
+    context 'when user configured kubernetes from Integration > Kubernetes' do
+      let!(:kubernetes_service) { create(:kubernetes_service, project: project) }
+
+      it { is_expected.to eq(kubernetes_service) }
+    end
+
+    context 'when user configured kubernetes from CI/CD > Clusters' do
+      let!(:cluster) { create(:cluster, :provided_by_gcp, projects: [project]) }
+      let(:platform_kubernetes) { cluster.platform_kubernetes }
+
+      it { is_expected.to eq(platform_kubernetes) }
+    end
+  end
 end

spec/support/prometheus/additional_metrics_shared_examples.rb

@@ -41,9 +41,9 @@ RSpec.shared_examples 'additional metrics query' do
     end
 
     describe 'project has Kubernetes service' do
-      let(:project) { create(:kubernetes_project) }
+      shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
         let(:environment) { create(:environment, slug: 'environment-slug', project: project) }
-      let(:kube_namespace) { project.kubernetes_service.actual_namespace }
+        let(:kube_namespace) { project.deployment_platform.actual_namespace }
 
         it_behaves_like 'query context containing environment slug and filter'
 
@@ -54,6 +54,20 @@ RSpec.shared_examples 'additional metrics query' do
         end
       end
 
+      context 'when user configured kubernetes from Integration > Kubernetes' do
+        let(:project) { create(:kubernetes_project) }
+
+        it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+      end
+
+      context 'when user configured kubernetes from CI/CD > Clusters' do
+        let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
+        let(:project) { cluster.project }
+
+        it_behaves_like 'same behavior between KubernetesService and Platform::Kubernetes'
+      end
+    end
+
     describe 'project without Kubernetes service' do
       it_behaves_like 'query context containing environment slug and filter'
 

spec/views/projects/pipelines_settings/_show.html.haml_spec.rb

@@ -35,7 +35,7 @@ describe 'projects/pipelines_settings/_show' do
 
   context 'when kubernetes is active' do
     before do
-      project.build_kubernetes_service(active: true)
+      create(:kubernetes_service, project: project)
     end
 
     context 'when auto devops domain is not defined' do

spec/workers/reactive_caching_worker_spec.rb

@@ -1,15 +1,28 @@
 require 'spec_helper'
 
 describe ReactiveCachingWorker do
-  let(:project) { create(:kubernetes_project) }
+  let(:service) { project.deployment_platform }
-  let(:service) { project.deployment_service }
-  subject { described_class.new.perform("KubernetesService", service.id) }
 
   describe '#perform' do
+    context 'when user configured kubernetes from Integration > Kubernetes' do
+      let(:project) { create(:kubernetes_project) }
+
       it 'calls #exclusively_update_reactive_cache!' do
         expect_any_instance_of(KubernetesService).to receive(:exclusively_update_reactive_cache!)
 
-      subject
+        described_class.new.perform("KubernetesService", service.id)
+      end
+    end
+
+    context 'when user configured kubernetes from CI/CD > Clusters' do
+      let!(:cluster) { create(:cluster, :project, :provided_by_gcp) }
+      let(:project) { cluster.project }
+
+      it 'calls #exclusively_update_reactive_cache!' do
+        expect_any_instance_of(Clusters::Platforms::Kubernetes).to receive(:exclusively_update_reactive_cache!)
+
+        described_class.new.perform("Clusters::Platforms::Kubernetes", service.id)
+      end
     end
   end
 end