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).

9 files changed, 47 insertions, 38 deletions

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'