Remove now unused KubernetesService methods

Now that KubernetesService can no longer be a DeploymentPlatform we can
remove all kubernetes client code and KubernetesService edge cases.

.rubocop_todo.yml

@@ -466,12 +466,10 @@ Rails/LinkToBlank:
 Rails/Presence:
   Exclude:
     - 'app/models/ci/pipeline.rb'
-    - 'app/models/clusters/platforms/kubernetes.rb'
     - 'app/models/concerns/mentionable.rb'
     - 'app/models/project_services/hipchat_service.rb'
     - 'app/models/project_services/irker_service.rb'
     - 'app/models/project_services/jira_service.rb'
-    - 'app/models/project_services/kubernetes_service.rb'
     - 'app/models/project_services/packagist_service.rb'
     - 'app/models/wiki_page.rb'
     - 'lib/gitlab/github_import/importer/releases_importer.rb'
@@ -514,7 +512,6 @@ Security/YAMLLoad:
     - 'spec/config/mail_room_spec.rb'
     - 'spec/initializers/secret_token_spec.rb'
     - 'spec/lib/gitlab/prometheus/additional_metrics_parser_spec.rb'
-    - 'spec/models/project_services/kubernetes_service_spec.rb'
 
 # Offense count: 34
 # Configuration parameters: EnforcedStyle.

app/models/project_services/kubernetes_service.rb

@@ -1,18 +1,8 @@
 # frozen_string_literal: true
 
-##
-# 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 < Service
-  include Gitlab::Kubernetes
-  include ReactiveCaching
-
   default_value_for :category, 'deployment'
 
-  self.reactive_cache_key = ->(service) { [service.class.model_name.singular, service.project_id] }
-
   # Namespace defaults to the project path, but can be overridden in case that
   # is an invalid or inappropriate name
   prop_accessor :namespace
@@ -47,8 +37,6 @@ class KubernetesService < Service
       message: Gitlab::Regex.kubernetes_namespace_regex_message
     }
 
-  after_save :clear_reactive_cache!
-
   def self.supported_events
     %w()
   end
@@ -94,72 +82,6 @@ class KubernetesService < Service
     ]
   end
 
-  def kubernetes_namespace_for(project)
-    if namespace.present?
-      namespace
-    else
-      default_namespace
-    end
-  end
-
-  # Check we can connect to the Kubernetes API
-  def test(*args)
-    kubeclient = build_kube_client!
-
-    kubeclient.core_client.discover
-    { success: kubeclient.core_client.discovered, result: "Checked API discovery endpoint" }
-  rescue => err
-    { success: false, result: err }
-  end
-
-  # Project param was added on
-  # https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/22011,
-  # as a way to keep this service compatible with
-  # Clusters::Platforms::Kubernetes, it won't be used on this method
-  # as it's only needed for Clusters::Cluster.
-  def predefined_variables(project:)
-    Gitlab::Ci::Variables::Collection.new.tap do |variables|
-      variables
-        .append(key: 'KUBE_URL', value: api_url)
-        .append(key: 'KUBE_TOKEN', value: token, public: false, masked: true)
-        .append(key: 'KUBE_NAMESPACE', value: kubernetes_namespace_for(project))
-        .append(key: 'KUBECONFIG', value: kubeconfig, public: false, file: true)
-
-      if ca_pem.present?
-        variables
-          .append(key: 'KUBE_CA_PEM', value: ca_pem)
-          .append(key: 'KUBE_CA_PEM_FILE', value: ca_pem, file: true)
-      end
-    end
-  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|
-      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, kubernetes_namespace_for(project), pod) }.compact
-      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 active? && project && !project.pending_delete?
-
-    # We may want to cache extra things in the future
-    { pods: read_pods }
-  end
-
-  def kubeclient
-    @kubeclient ||= build_kube_client!
-  end
-
   def deprecated?
     true
   end
@@ -186,14 +108,6 @@ class KubernetesService < Service
 
   private
 
-  def kubeconfig
-    to_kubeconfig(
-      url: api_url,
-      namespace: kubernetes_namespace_for(project),
-      token: token,
-      ca_pem: ca_pem)
-  end
-
   def namespace_placeholder
     default_namespace || TEMPLATE_PLACEHOLDER
   end
@@ -205,49 +119,6 @@ class KubernetesService < Service
     slug.gsub(/[^-a-z0-9]/, '-').gsub(/^-+/, '')
   end
 
-  def build_kube_client!
-    raise "Incomplete settings" unless api_url && kubernetes_namespace_for(project) && token
-
-    Gitlab::Kubernetes::KubeClient.new(
-      api_url,
-      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_kube_client!
-
-    kubeclient.get_pods(namespace: kubernetes_namespace_for(project)).as_json
-  rescue Kubeclient::ResourceNotFoundError
-    []
-  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 terminal_auth
-    {
-      token: token,
-      ca_pem: ca_pem,
-      max_session_time: Gitlab::CurrentSettings.terminal_max_session_time
-    }
-  end
-
   def enforce_namespace_to_lower_case
     self.namespace = self.namespace&.downcase
   end

app/services/prometheus/adapter_service.rb

@@ -27,12 +27,9 @@ module Prometheus
     end
 
     def cluster_prometheus_adapter
-      return unless deployment_platform.respond_to?(:cluster)
+      application = deployment_platform&.cluster&.application_prometheus
 
-      cluster = deployment_platform.cluster
+      application if application&.available?
-      return unless cluster.application_prometheus&.available?
-
-      cluster.application_prometheus
     end
   end
 end

spec/models/deployment_spec.rb

@@ -462,12 +462,6 @@ describe Deployment do
       it { is_expected.to be_nil }
     end
 
-    context 'project uses the kubernetes service for deployments' do
-      let!(:service) { create(:kubernetes_service, project: project) }
-
-      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) }

spec/models/project_services/kubernetes_service_spec.rb

@@ -142,235 +142,6 @@ describe KubernetesService, :use_clean_rails_memory_store_caching do
     end
   end
 
-  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
-        expect(subject).to match(Gitlab::Regex.kubernetes_namespace_regex)
-        expect(subject).to eq(expected_namespace)
-      end
-    end
-
-    it_behaves_like 'a correctly formatted namespace' do
-      let(:expected_namespace) { service.send(:default_namespace) }
-    end
-
-    context 'when the project path contains forbidden characters' do
-      before do
-        project.path = '-a_Strange.Path--forSure'
-      end
-
-      it_behaves_like 'a correctly formatted namespace' do
-        let(:expected_namespace) { "a-strange-path--forsure-#{project.id}" }
-      end
-    end
-
-    context 'when namespace is specified' do
-      before do
-        service.namespace = 'my-namespace'
-      end
-
-      it_behaves_like 'a correctly formatted namespace' do
-        let(:expected_namespace) { 'my-namespace' }
-      end
-    end
-
-    context 'when service is not assigned to project' do
-      before do
-        service.project = nil
-      end
-
-      it 'does not return namespace' do
-        is_expected.to be_nil
-      end
-    end
-  end
-
-  describe '#test' do
-    let(:discovery_url) { 'https://kubernetes.example.com/api/v1' }
-
-    before do
-      stub_kubeclient_discover(service.api_url)
-    end
-
-    context 'with path prefix in api_url' do
-      let(:discovery_url) { 'https://kubernetes.example.com/prefix/api/v1' }
-
-      it 'tests with the prefix' do
-        service.api_url = 'https://kubernetes.example.com/prefix'
-        stub_kubeclient_discover(service.api_url)
-
-        expect(service.test[:success]).to be_truthy
-        expect(WebMock).to have_requested(:get, discovery_url).once
-      end
-    end
-
-    context 'with custom CA certificate' do
-      it 'is added to the certificate store' do
-        service.ca_pem = "CA PEM DATA"
-
-        cert = double("certificate")
-        expect(OpenSSL::X509::Certificate).to receive(:new).with(service.ca_pem).and_return(cert)
-        expect_any_instance_of(OpenSSL::X509::Store).to receive(:add_cert).with(cert)
-
-        expect(service.test[:success]).to be_truthy
-        expect(WebMock).to have_requested(:get, discovery_url).once
-      end
-    end
-
-    context 'success' do
-      it 'reads the discovery endpoint' do
-        expect(service.test[:success]).to be_truthy
-        expect(WebMock).to have_requested(:get, discovery_url).once
-      end
-    end
-
-    context 'failure' do
-      it 'fails to read the discovery endpoint' do
-        WebMock.stub_request(:get, service.api_url + '/api/v1').to_return(status: 404)
-
-        expect(service.test[:success]).to be_falsy
-        expect(WebMock).to have_requested(:get, discovery_url).once
-      end
-    end
-  end
-
-  describe '#predefined_variable' do
-    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 DATA')
-
-      YAML.dump(config)
-    end
-
-    before do
-      subject.api_url = 'https://kube.domain.com'
-      subject.token = 'token'
-      subject.ca_pem = 'CA PEM DATA'
-      subject.project = project
-    end
-
-    shared_examples 'setting variables' do
-      it 'sets the variables' do
-        expect(subject.predefined_variables(project: project)).to include(
-          { key: 'KUBE_URL', value: 'https://kube.domain.com', public: true },
-          { key: 'KUBE_TOKEN', value: 'token', public: false, masked: true },
-          { key: 'KUBE_NAMESPACE', value: namespace, public: true },
-          { key: 'KUBECONFIG', value: kubeconfig, public: false, file: true },
-          { key: 'KUBE_CA_PEM', value: 'CA PEM DATA', public: true },
-          { key: 'KUBE_CA_PEM_FILE', value: 'CA PEM DATA', public: true, file: true }
-        )
-      end
-    end
-
-    context 'namespace is provided' do
-      let(:namespace) { 'my-project' }
-
-      before do
-        subject.namespace = namespace
-      end
-
-      it_behaves_like 'setting variables'
-    end
-
-    context 'no namespace provided' do
-      let(:namespace) { subject.kubernetes_namespace_for(project) }
-
-      it_behaves_like 'setting variables'
-
-      it 'sets the KUBE_NAMESPACE' do
-        kube_namespace = subject.predefined_variables(project: project).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
-    let(:environment) { build(:environment, project: project, name: "env", slug: "env-000000") }
-
-    subject { service.terminals(environment) }
-
-    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(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) }
-
-      before do
-        stub_reactive_cache(
-          service,
-          pods: [pod, pod, pod_with_no_terminal, kube_pod(environment_slug: "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(:namespace) { service.kubernetes_namespace_for(project) }
-
-    context 'when service is inactive' do
-      before do
-        service.active = false
-      end
-
-      it { is_expected.to be_nil }
-    end
-
-    context 'when kubernetes responds with valid pods' do
-      before do
-        stub_kubeclient_pods(namespace)
-        stub_kubeclient_deployments(namespace) # Used by EE
-      end
-
-      it { is_expected.to include(pods: [kube_pod]) }
-    end
-
-    context 'when kubernetes responds with 500s' do
-      before do
-        stub_kubeclient_pods(namespace, status: 500)
-        stub_kubeclient_deployments(namespace, status: 500) # Used by EE
-      end
-
-      it { expect { subject }.to raise_error(Kubeclient::HttpError) }
-    end
-
-    context 'when kubernetes responds with 404s' do
-      before do
-        stub_kubeclient_pods(namespace, status: 404)
-        stub_kubeclient_deployments(namespace, status: 404) # Used by EE
-      end
-
-      it { is_expected.to include(pods: []) }
-    end
-  end
-
   describe "#deprecated?" do
     let(:kubernetes_service) { create(:kubernetes_service) }