Remove legacy Kubernetes #actual_namespace61935-remove-code-left-over-from-when-clusters-were-always-project-specific

When Kubernetes clusters were originally built they could only
exist at the project level, and so there was logic included
that assumed there would only ever be a single Kubernetes
namespace per cluster. We now support clusters at the group
and instance level, which allows multiple namespaces.

This change consolidates various project-specific fallbacks to
generate namespaces, and hands all responsibility to the
Clusters::KubernetesNamespace model. There is now no concept of
a single namespace for a Clusters::Platforms::Kubernetes; to
retrieve a namespace a project must now be supplied in all cases.

This simplifies upcoming work to use a separate Kubernetes
namespace per project environment (instead of a namespace
per project).

15 files changed, 94 insertions, 106 deletions

diff --git a/app/finders/projects/serverless/functions_finder.rb b/app/finders/projects/serverless/functions_finder.rb
index d9802598c64..e5bffccabfe 100644
--- a/app/finders/projects/serverless/functions_finder.rb
+++ b/app/finders/projects/serverless/functions_finder.rb
@@ -3,6 +3,8 @@
 module Projects
   module Serverless
     class FunctionsFinder
+      attr_reader :project
+
       def initialize(project)
         @clusters = project.clusters
         @project = project
@@ -27,7 +29,7 @@ module Projects
           environment_scope == c.environment_scope
         end
 
-        func = ::Serverless::Function.new(@project, name, cluster.platform_kubernetes&.actual_namespace)
+        func = ::Serverless::Function.new(project, name, cluster.kubernetes_namespace_for(project))
         prometheus_adapter.query(:knative_invocation, func)
       end
 
@@ -43,7 +45,7 @@ module Projects
         clusters_with_knative_installed.preload_knative.map do |cluster|
           next if environment_scope != cluster.environment_scope
 
-          services = cluster.application_knative.services_for(ns: cluster.platform_kubernetes&.actual_namespace)
+          services = cluster.application_knative.services_for(ns: cluster.kubernetes_namespace_for(project))
             .select { |svc| svc["metadata"]["name"] == name }
 
           add_metadata(cluster, services).first unless services.nil?
@@ -52,7 +54,7 @@ module Projects
 
       def knative_services
         clusters_with_knative_installed.preload_knative.map do |cluster|
-          services = cluster.application_knative.services_for(ns: cluster.platform_kubernetes&.actual_namespace)
+          services = cluster.application_knative.services_for(ns: cluster.kubernetes_namespace_for(project))
           add_metadata(cluster, services) unless services.nil?
         end
       end
@@ -64,7 +66,7 @@ module Projects
 
           if services.length == 1
             s["podcount"] = cluster.application_knative.service_pod_details(
-              cluster.platform_kubernetes&.actual_namespace,
+              cluster.kubernetes_namespace_for(project),
               s["metadata"]["name"]).length
           end
         end
@@ -76,7 +78,7 @@ module Projects
 
       # rubocop: disable CodeReuse/ServiceClass
       def prometheus_adapter
-        @prometheus_adapter ||= ::Prometheus::AdapterService.new(@project).prometheus_adapter
+        @prometheus_adapter ||= ::Prometheus::AdapterService.new(project).prometheus_adapter
       end
       # rubocop: enable CodeReuse/ServiceClass
     end
diff --git a/app/models/clusters/cluster.rb b/app/models/clusters/cluster.rb
index 9299e61dad3..f7ea7accab2 100644
--- a/app/models/clusters/cluster.rb
+++ b/app/models/clusters/cluster.rb
@@ -45,7 +45,6 @@ module Clusters
     has_one :application_knative, class_name: 'Clusters::Applications::Knative'
 
     has_many :kubernetes_namespaces
-    has_one :kubernetes_namespace, -> { order(id: :desc) }, class_name: 'Clusters::KubernetesNamespace'
 
     accepts_nested_attributes_for :provider_gcp, update_only: true
     accepts_nested_attributes_for :platform_kubernetes, update_only: true
@@ -108,7 +107,7 @@ module Clusters
 
     scope :preload_knative, -> {
       preload(
-        :kubernetes_namespace,
+        :kubernetes_namespaces,
         :platform_kubernetes,
         :application_knative
       )
@@ -187,16 +186,16 @@ module Clusters
       platform_kubernetes.kubeclient if kubernetes?
     end
 
+    def kubernetes_namespace_for(project)
+      find_or_initialize_kubernetes_namespace_for_project(project).namespace
+    end
+
     def find_or_initialize_kubernetes_namespace_for_project(project)
-      if project_type?
-        kubernetes_namespaces.find_or_initialize_by(
-          project: project,
-          cluster_project: cluster_project
-        )
-      else
-        kubernetes_namespaces.find_or_initialize_by(
-          project: project
-        )
+      attributes = { project: project }
+      attributes[:cluster_project] = cluster_project if project_type?
+
+      kubernetes_namespaces.find_or_initialize_by(attributes).tap do |namespace|
+        namespace.set_defaults
       end
     end
 
diff --git a/app/models/clusters/platforms/kubernetes.rb b/app/models/clusters/platforms/kubernetes.rb
index 3b7b93e7631..9b951578aee 100644
--- a/app/models/clusters/platforms/kubernetes.rb
+++ b/app/models/clusters/platforms/kubernetes.rb
@@ -52,11 +52,14 @@ module Clusters
 
       alias_attribute :ca_pem, :ca_cert
 
-      delegate :project, to: :cluster, allow_nil: true
       delegate :enabled?, to: :cluster, allow_nil: true
       delegate :provided_by_user?, to: :cluster, allow_nil: true
       delegate :allow_user_defined_namespace?, to: :cluster, allow_nil: true
-      delegate :kubernetes_namespace, to: :cluster
+
+      # This is just to maintain compatibility with KubernetesService, which
+      # will be removed in https://gitlab.com/gitlab-org/gitlab-ce/issues/39217.
+      # It can be removed once KubernetesService is gone.
+      delegate :kubernetes_namespace_for, to: :cluster, allow_nil: true
 
       alias_method :active?, :enabled?
 
@@ -68,18 +71,6 @@ module Clusters
 
       default_value_for :authorization_type, :rbac
 
-      def actual_namespace
-        if namespace.present?
-          namespace
-        else
-          default_namespace
-        end
-      end
-
-      def namespace_for(project)
-        cluster.find_or_initialize_kubernetes_namespace_for_project(project).namespace
-      end
-
       def predefined_variables(project:)
         Gitlab::Ci::Variables::Collection.new.tap do |variables|
           variables.append(key: 'KUBE_URL', value: api_url)
@@ -98,11 +89,13 @@ module Clusters
             # Once we have marked all project-level clusters that make use of this
             # behaviour as "unmanaged", we can remove the `cluster.project_type?`
             # check here.
+            project_namespace = cluster.kubernetes_namespace_for(project)
+
             variables
               .append(key: 'KUBE_URL', value: api_url)
               .append(key: 'KUBE_TOKEN', value: token, public: false, masked: true)
-              .append(key: 'KUBE_NAMESPACE', value: actual_namespace)
-              .append(key: 'KUBECONFIG', value: kubeconfig, public: false, file: true)
+              .append(key: 'KUBE_NAMESPACE', value: project_namespace)
+              .append(key: 'KUBECONFIG', value: kubeconfig(project_namespace), public: false, file: true)
           end
 
           variables.concat(cluster.predefined_variables)
@@ -115,8 +108,10 @@ module Clusters
       # short time later
       def terminals(environment)
         with_reactive_cache do |data|
+          project = environment.project
+
           pods = filter_by_project_environment(data[:pods], project.full_path_slug, environment.slug)
-          terminals = pods.flat_map { |pod| terminals_for_pod(api_url, actual_namespace, pod) }.compact
+          terminals = pods.flat_map { |pod| terminals_for_pod(api_url, cluster.kubernetes_namespace_for(project), pod) }.compact
           terminals.each { |terminal| add_terminal_auth(terminal, terminal_auth) }
         end
       end
@@ -124,7 +119,7 @@ module Clusters
       # 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?
+        return unless enabled?
 
         # We may want to cache extra things in the future
         { pods: read_pods }
@@ -136,33 +131,16 @@ module Clusters
 
       private
 
-      def kubeconfig
+      def kubeconfig(namespace)
         to_kubeconfig(
           url: api_url,
-          namespace: actual_namespace,
+          namespace: namespace,
           token: token,
           ca_pem: ca_pem)
       end
 
-      def default_namespace
-        kubernetes_namespace&.namespace.presence || fallback_default_namespace
-      end
-
-      # DEPRECATED
-      #
-      # On 11.4 Clusters::KubernetesNamespace was introduced, this model will allow to
-      # have multiple namespaces per project. This method will be removed after migration
-      # has been completed.
-      def fallback_default_namespace
-        return unless project
-
-        slug = "#{project.path}-#{project.id}".downcase
-        Gitlab::NamespaceSanitizer.sanitize(slug)
-      end
-
       def build_kube_client!
         raise "Incomplete settings" unless api_url
-        raise "No namespace" if cluster.project_type? && actual_namespace.empty? # can probably remove this line once we remove #actual_namespace
 
         unless (username && password) || token
           raise "Either username/password or token is required to access API"
@@ -178,9 +156,13 @@ module Clusters
 
       # Returns a hash of all pods in the namespace
       def read_pods
-        kubeclient = build_kube_client!
+        # TODO: The project lookup here should be moved (to environment?),
+        # which will enable reading pods from the correct namespace for group
+        # and instance clusters.
+        # This will be done in https://gitlab.com/gitlab-org/gitlab-ce/issues/61156
+        return [] unless cluster.project_type?
 
-        kubeclient.get_pods(namespace: actual_namespace).as_json
+        kubeclient.get_pods(namespace: cluster.kubernetes_namespace_for(cluster.first_project)).as_json
       rescue Kubeclient::ResourceNotFoundError
         []
       end
diff --git a/app/models/clusters/project.rb b/app/models/clusters/project.rb
index d2b68b3f117..e0bf60164ba 100644
--- a/app/models/clusters/project.rb
+++ b/app/models/clusters/project.rb
@@ -8,6 +8,5 @@ module Clusters
     belongs_to :project, class_name: '::Project'
 
     has_many :kubernetes_namespaces, class_name: 'Clusters::KubernetesNamespace', foreign_key: :cluster_project_id
-    has_one :kubernetes_namespace, -> { order(id: :desc) }, class_name: 'Clusters::KubernetesNamespace', foreign_key: :cluster_project_id
   end
 end
diff --git a/app/models/project_services/kubernetes_service.rb b/app/models/project_services/kubernetes_service.rb
index fc8afa9bead..aa6b4aa1d5e 100644
--- a/app/models/project_services/kubernetes_service.rb
+++ b/app/models/project_services/kubernetes_service.rb
@@ -86,7 +86,7 @@ class KubernetesService < DeploymentService
     ]
   end
 
-  def actual_namespace
+  def kubernetes_namespace_for(project)
     if namespace.present?
       namespace
     else
@@ -94,10 +94,6 @@ class KubernetesService < DeploymentService
     end
   end
 
-  def namespace_for(project)
-    actual_namespace
-  end
-
   # Check we can connect to the Kubernetes API
   def test(*args)
     kubeclient = build_kube_client!
@@ -118,7 +114,7 @@ class KubernetesService < DeploymentService
       variables
         .append(key: 'KUBE_URL', value: api_url)
         .append(key: 'KUBE_TOKEN', value: token, public: false, masked: true)
-        .append(key: 'KUBE_NAMESPACE', value: actual_namespace)
+        .append(key: 'KUBE_NAMESPACE', value: kubernetes_namespace_for(project))
         .append(key: 'KUBECONFIG', value: kubeconfig, public: false, file: true)
 
       if ca_pem.present?
@@ -135,8 +131,10 @@ class KubernetesService < DeploymentService
   # short time later
   def terminals(environment)
     with_reactive_cache do |data|
+      project = environment.project
+
       pods = filter_by_project_environment(data[:pods], project.full_path_slug, environment.slug)
-      terminals = pods.flat_map { |pod| terminals_for_pod(api_url, actual_namespace, pod) }.compact
+      terminals = pods.flat_map { |pod| terminals_for_pod(api_url, kubernetes_namespace_for(project), pod) }.compact
       terminals.each { |terminal| add_terminal_auth(terminal, terminal_auth) }
     end
   end
@@ -173,7 +171,7 @@ class KubernetesService < DeploymentService
   def kubeconfig
     to_kubeconfig(
       url: api_url,
-      namespace: actual_namespace,
+      namespace: kubernetes_namespace_for(project),
       token: token,
       ca_pem: ca_pem)
   end
@@ -190,7 +188,7 @@ class KubernetesService < DeploymentService
   end
 
   def build_kube_client!
-    raise "Incomplete settings" unless api_url && actual_namespace && token
+    raise "Incomplete settings" unless api_url && kubernetes_namespace_for(project) && token
 
     Gitlab::Kubernetes::KubeClient.new(
       api_url,
@@ -204,7 +202,7 @@ class KubernetesService < DeploymentService
   def read_pods
     kubeclient = build_kube_client!
 
-    kubeclient.get_pods(namespace: actual_namespace).as_json
+    kubeclient.get_pods(namespace: kubernetes_namespace_for(project)).as_json
   rescue Kubeclient::ResourceNotFoundError
     []
   end
diff --git a/lib/gitlab/prometheus/query_variables.rb b/lib/gitlab/prometheus/query_variables.rb
index dca09aef47d..9cc21129547 100644
--- a/lib/gitlab/prometheus/query_variables.rb
+++ b/lib/gitlab/prometheus/query_variables.rb
@@ -5,8 +5,7 @@ module Gitlab
     module QueryVariables
       def self.call(environment)
         deployment_platform = environment.deployment_platform
-        namespace = deployment_platform&.namespace_for(environment.project) ||
-          deployment_platform&.actual_namespace || ''
+        namespace = deployment_platform&.kubernetes_namespace_for(environment.project) || ''
 
         {
           ci_environment_slug: environment.slug,
diff --git a/spec/lib/gitlab/prometheus/query_variables_spec.rb b/spec/lib/gitlab/prometheus/query_variables_spec.rb
index 048f4af6020..6dc99ef26ec 100644
--- a/spec/lib/gitlab/prometheus/query_variables_spec.rb
+++ b/spec/lib/gitlab/prometheus/query_variables_spec.rb
@@ -23,7 +23,7 @@ describe Gitlab::Prometheus::QueryVariables do
 
     context 'with deployment platform' do
       context 'with project cluster' do
-        let(:kube_namespace) { environment.deployment_platform.actual_namespace }
+        let(:kube_namespace) { environment.deployment_platform.cluster.kubernetes_namespace_for(project) }
 
         before do
           create(:cluster, :project, :provided_by_user, projects: [project])
diff --git a/spec/models/clusters/cluster_spec.rb b/spec/models/clusters/cluster_spec.rb
index 58203da5b22..60065ff22af 100644
--- a/spec/models/clusters/cluster_spec.rb
+++ b/spec/models/clusters/cluster_spec.rb
@@ -17,7 +17,6 @@ describe Clusters::Cluster do
   it { is_expected.to have_one(:application_prometheus) }
   it { is_expected.to have_one(:application_runner) }
   it { is_expected.to have_many(:kubernetes_namespaces) }
-  it { is_expected.to have_one(:kubernetes_namespace) }
   it { is_expected.to have_one(:cluster_project) }
 
   it { is_expected.to delegate_method(:status).to(:provider) }
diff --git a/spec/models/clusters/platforms/kubernetes_spec.rb b/spec/models/clusters/platforms/kubernetes_spec.rb
index e35d14f2282..c485850c16e 100644
--- a/spec/models/clusters/platforms/kubernetes_spec.rb
+++ b/spec/models/clusters/platforms/kubernetes_spec.rb
@@ -15,10 +15,8 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
   it { is_expected.to validate_presence_of(:api_url) }
   it { is_expected.to validate_presence_of(:token) }
 
-  it { is_expected.to delegate_method(:project).to(:cluster) }
   it { is_expected.to delegate_method(:enabled?).to(:cluster) }
   it { is_expected.to delegate_method(:provided_by_user?).to(:cluster) }
-  it { is_expected.to delegate_method(:kubernetes_namespace).to(:cluster) }
 
   it_behaves_like 'having unique enum values'
 
@@ -209,7 +207,7 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
     it { is_expected.to be_truthy }
   end
 
-  describe '#actual_namespace' do
+  describe '#kubernetes_namespace_for' do
     let(:cluster) { create(:cluster, :project) }
     let(:project) { cluster.project }
 
@@ -219,7 +217,7 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
              namespace: namespace)
     end
 
-    subject { platform.actual_namespace }
+    subject { platform.kubernetes_namespace_for(project) }
 
     context 'with a namespace assigned' do
       let(:namespace) { 'namespace-123' }
@@ -305,8 +303,6 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
     end
 
     context 'no namespace provided' do
-      let(:namespace) { kubernetes.actual_namespace }
-
       it_behaves_like 'setting variables'
 
       it 'sets KUBE_TOKEN' do
@@ -389,7 +385,7 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
     end
 
     context 'with valid pods' do
-      let(:pod) { kube_pod(environment_slug: environment.slug, project_slug: project.full_path_slug) }
+      let(:pod) { kube_pod(environment_slug: environment.slug, namespace: cluster.kubernetes_namespace_for(project), project_slug: project.full_path_slug) }
       let(:pod_with_no_terminal) { kube_pod(environment_slug: environment.slug, project_slug: project.full_path_slug, status: "Pending") }
       let(:terminals) { kube_terminals(service, pod) }
 
@@ -419,6 +415,7 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
     let!(:cluster) { create(:cluster, :project, enabled: enabled, platform_kubernetes: service) }
     let(:service) { create(:cluster_platform_kubernetes, :configured) }
     let(:enabled) { true }
+    let(:namespace) { cluster.kubernetes_namespace_for(cluster.project) }
 
     context 'when cluster is disabled' do
       let(:enabled) { false }
@@ -428,8 +425,8 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
 
     context 'when kubernetes responds with valid pods and deployments' do
       before do
-        stub_kubeclient_pods
-        stub_kubeclient_deployments
+        stub_kubeclient_pods(namespace)
+        stub_kubeclient_deployments(namespace)
       end
 
       it { is_expected.to include(pods: [kube_pod]) }
@@ -437,8 +434,8 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
 
     context 'when kubernetes responds with 500s' do
       before do
-        stub_kubeclient_pods(status: 500)
-        stub_kubeclient_deployments(status: 500)
+        stub_kubeclient_pods(namespace, status: 500)
+        stub_kubeclient_deployments(namespace, status: 500)
       end
 
       it { expect { subject }.to raise_error(Kubeclient::HttpError) }
@@ -446,12 +443,18 @@ describe Clusters::Platforms::Kubernetes, :use_clean_rails_memory_store_caching
 
     context 'when kubernetes responds with 404s' do
       before do
-        stub_kubeclient_pods(status: 404)
-        stub_kubeclient_deployments(status: 404)
+        stub_kubeclient_pods(namespace, status: 404)
+        stub_kubeclient_deployments(namespace, status: 404)
       end
 
       it { is_expected.to include(pods: []) }
     end
+
+    context 'when the cluster is not project level' do
+      let(:cluster) { create(:cluster, :group, platform_kubernetes: service) }
+
+      it { is_expected.to include(pods: []) }
+    end
   end
 
   describe '#update_kubernetes_namespace' do
diff --git a/spec/models/clusters/project_spec.rb b/spec/models/clusters/project_spec.rb
index 2f017e69251..671af085d10 100644
--- a/spec/models/clusters/project_spec.rb
+++ b/spec/models/clusters/project_spec.rb
@@ -6,5 +6,4 @@ describe Clusters::Project do
   it { is_expected.to belong_to(:cluster) }
   it { is_expected.to belong_to(:project) }
   it { is_expected.to have_many(:kubernetes_namespaces) }
-  it { is_expected.to have_one(:kubernetes_namespace) }
 end
diff --git a/spec/models/project_services/kubernetes_service_spec.rb b/spec/models/project_services/kubernetes_service_spec.rb
index 3a381cb405d..2fce120381b 100644
--- a/spec/models/project_services/kubernetes_service_spec.rb
+++ b/spec/models/project_services/kubernetes_service_spec.rb
@@ -161,8 +161,8 @@ describe KubernetesService, :use_clean_rails_memory_store_caching do
     end
   end
 
-  describe '#actual_namespace' do
-    subject { service.actual_namespace }
+  describe '#kubernetes_namespace_for' do
+    subject { service.kubernetes_namespace_for(project) }
 
     shared_examples 'a correctly formatted namespace' do
       it 'returns a valid Kubernetes namespace name' do
@@ -298,7 +298,7 @@ describe KubernetesService, :use_clean_rails_memory_store_caching do
     end
 
     context 'no namespace provided' do
-      let(:namespace) { subject.actual_namespace }
+      let(:namespace) { subject.kubernetes_namespace_for(project) }
 
       it_behaves_like 'setting variables'
 
@@ -325,7 +325,7 @@ describe KubernetesService, :use_clean_rails_memory_store_caching do
     end
 
     context 'with valid pods' do
-      let(:pod) { kube_pod(environment_slug: environment.slug, project_slug: project.full_path_slug) }
+      let(:pod) { kube_pod(environment_slug: environment.slug, namespace: service.kubernetes_namespace_for(project), project_slug: project.full_path_slug) }
       let(:pod_with_no_terminal) { kube_pod(environment_slug: environment.slug, project_slug: project.full_path_slug, status: "Pending") }
       let(:terminals) { kube_terminals(service, pod) }
 
@@ -352,6 +352,8 @@ describe KubernetesService, :use_clean_rails_memory_store_caching do
   describe '#calculate_reactive_cache' do
     subject { service.calculate_reactive_cache }
 
+    let(:namespace) { service.kubernetes_namespace_for(project) }
+
     context 'when service is inactive' do
       before do
         service.active = false
@@ -362,8 +364,8 @@ describe KubernetesService, :use_clean_rails_memory_store_caching do
 
     context 'when kubernetes responds with valid pods' do
       before do
-        stub_kubeclient_pods
-        stub_kubeclient_deployments # Used by EE
+        stub_kubeclient_pods(namespace)
+        stub_kubeclient_deployments(namespace) # Used by EE
       end
 
       it { is_expected.to include(pods: [kube_pod]) }
@@ -371,8 +373,8 @@ describe KubernetesService, :use_clean_rails_memory_store_caching do
 
     context 'when kubernetes responds with 500s' do
       before do
-        stub_kubeclient_pods(status: 500)
-        stub_kubeclient_deployments(status: 500) # Used by EE
+        stub_kubeclient_pods(namespace, status: 500)
+        stub_kubeclient_deployments(namespace, status: 500) # Used by EE
       end
 
       it { expect { subject }.to raise_error(Kubeclient::HttpError) }
@@ -380,8 +382,8 @@ describe KubernetesService, :use_clean_rails_memory_store_caching do
 
     context 'when kubernetes responds with 404s' do
       before do
-        stub_kubeclient_pods(status: 404)
-        stub_kubeclient_deployments(status: 404) # Used by EE
+        stub_kubeclient_pods(namespace, status: 404)
+        stub_kubeclient_deployments(namespace, status: 404) # Used by EE
       end
 
       it { is_expected.to include(pods: []) }
diff --git a/spec/requests/api/project_clusters_spec.rb b/spec/requests/api/project_clusters_spec.rb
index 5357be3cdee..fc0381159dd 100644
--- a/spec/requests/api/project_clusters_spec.rb
+++ b/spec/requests/api/project_clusters_spec.rb
@@ -351,7 +351,7 @@ describe API::ProjectClusters do
         it 'does not update cluster attributes' do
           expect(cluster.domain).not_to eq('new_domain.com')
           expect(cluster.platform_kubernetes.namespace).not_to eq('invalid_namespace')
-          expect(cluster.kubernetes_namespace.namespace).not_to eq('invalid_namespace')
+          expect(cluster.kubernetes_namespace_for(project)).not_to eq('invalid_namespace')
         end
 
         it 'returns validation errors' do
diff --git a/spec/services/clusters/gcp/kubernetes/create_or_update_namespace_service_spec.rb b/spec/services/clusters/gcp/kubernetes/create_or_update_namespace_service_spec.rb
index 18f218fc236..be052a07da7 100644
--- a/spec/services/clusters/gcp/kubernetes/create_or_update_namespace_service_spec.rb
+++ b/spec/services/clusters/gcp/kubernetes/create_or_update_namespace_service_spec.rb
@@ -113,7 +113,7 @@ describe Clusters::Gcp::Kubernetes::CreateOrUpdateNamespaceService, '#execute' d
       it 'does not create any Clusters::KubernetesNamespace' do
         subject
 
-        expect(cluster.kubernetes_namespace).to eq(kubernetes_namespace)
+        expect(cluster.kubernetes_namespaces).to eq([kubernetes_namespace])
       end
 
       it 'creates project service account' do
diff --git a/spec/support/helpers/kubernetes_helpers.rb b/spec/support/helpers/kubernetes_helpers.rb
index ac52acb6570..78b7ae9c00c 100644
--- a/spec/support/helpers/kubernetes_helpers.rb
+++ b/spec/support/helpers/kubernetes_helpers.rb
@@ -24,30 +24,34 @@ module KubernetesHelpers
     WebMock.stub_request(:get, api_url + '/apis/serving.knative.dev/v1alpha1').to_return(kube_response(kube_v1alpha1_serving_knative_discovery_body))
   end
 
-  def stub_kubeclient_service_pods(response = nil)
+  def stub_kubeclient_service_pods(status: nil)
     stub_kubeclient_discover(service.api_url)
     pods_url = service.api_url + "/api/v1/pods"
+    response = { status: status } if status
 
     WebMock.stub_request(:get, pods_url).to_return(response || kube_pods_response)
   end
 
-  def stub_kubeclient_pods(response = nil)
+  def stub_kubeclient_pods(namespace, status: nil)
     stub_kubeclient_discover(service.api_url)
-    pods_url = service.api_url + "/api/v1/namespaces/#{service.actual_namespace}/pods"
+    pods_url = service.api_url + "/api/v1/namespaces/#{namespace}/pods"
+    response = { status: status } if status
 
     WebMock.stub_request(:get, pods_url).to_return(response || kube_pods_response)
   end
 
-  def stub_kubeclient_logs(pod_name, response = nil)
+  def stub_kubeclient_logs(pod_name, namespace, status: nil)
     stub_kubeclient_discover(service.api_url)
-    logs_url = service.api_url + "/api/v1/namespaces/#{service.actual_namespace}/pods/#{pod_name}/log?tailLines=#{Clusters::Platforms::Kubernetes::LOGS_LIMIT}"
+    logs_url = service.api_url + "/api/v1/namespaces/#{namespace}/pods/#{pod_name}/log?tailLines=#{Clusters::Platforms::Kubernetes::LOGS_LIMIT}"
+    response = { status: status } if status
 
     WebMock.stub_request(:get, logs_url).to_return(response || kube_logs_response)
   end
 
-  def stub_kubeclient_deployments(response = nil)
+  def stub_kubeclient_deployments(namespace, status: nil)
     stub_kubeclient_discover(service.api_url)
-    deployments_url = service.api_url + "/apis/extensions/v1beta1/namespaces/#{service.actual_namespace}/deployments"
+    deployments_url = service.api_url + "/apis/extensions/v1beta1/namespaces/#{namespace}/deployments"
+    response = { status: status } if status
 
     WebMock.stub_request(:get, deployments_url).to_return(response || kube_deployments_response)
   end
@@ -250,10 +254,11 @@ module KubernetesHelpers
 
   # This is a partial response, it will have many more elements in reality but
   # these are the ones we care about at the moment
-  def kube_pod(name: "kube-pod", environment_slug: "production", project_slug: "project-path-slug", status: "Running", track: nil)
+  def kube_pod(name: "kube-pod", environment_slug: "production", namespace: "project-namespace", project_slug: "project-path-slug", status: "Running", track: nil)
     {
       "metadata" => {
         "name" => name,
+        "namespace" => namespace,
         "generate_name" => "generated-name-with-suffix",
         "creationTimestamp" => "2016-11-25T19:55:19Z",
         "annotations" => {
@@ -369,12 +374,13 @@ module KubernetesHelpers
 
   def kube_terminals(service, pod)
     pod_name = pod['metadata']['name']
+    pod_namespace = pod['metadata']['namespace']
     containers = pod['spec']['containers']
 
     containers.map do |container|
       terminal = {
         selectors: { pod: pod_name, container: container['name'] },
-        url:  container_exec_url(service.api_url, service.actual_namespace, pod_name, container['name']),
+        url:  container_exec_url(service.api_url, pod_namespace, pod_name, container['name']),
         subprotocols: ['channel.k8s.io'],
         headers: { 'Authorization' => ["Bearer #{service.token}"] },
         created_at: DateTime.parse(pod['metadata']['creationTimestamp']),
diff --git a/spec/support/prometheus/additional_metrics_shared_examples.rb b/spec/support/prometheus/additional_metrics_shared_examples.rb
index 0fd67531c3b..8044b061ca5 100644
--- a/spec/support/prometheus/additional_metrics_shared_examples.rb
+++ b/spec/support/prometheus/additional_metrics_shared_examples.rb
@@ -46,7 +46,7 @@ RSpec.shared_examples 'additional metrics query' do
     describe 'project has Kubernetes service' do
       shared_examples 'same behavior between KubernetesService and Platform::Kubernetes' do
         let(:environment) { create(:environment, slug: 'environment-slug', project: project) }
-        let(:kube_namespace) { project.deployment_platform.actual_namespace }
+        let(:kube_namespace) { project.deployment_platform.kubernetes_namespace_for(project) }
 
         it_behaves_like 'query context containing environment slug and filter'