Extend Cluster Applications to allow installation of Prometheus

app/assets/javascripts/clusters/clusters_bundle.js

@@ -30,6 +30,7 @@ export default class Clusters {
       installHelmPath,
       installIngressPath,
       installRunnerPath,
+      installPrometheusPath,
       clusterStatus,
       clusterStatusReason,
       helpPath,
@@ -44,6 +45,7 @@ export default class Clusters {
       installHelmEndpoint: installHelmPath,
       installIngressEndpoint: installIngressPath,
       installRunnerEndpoint: installRunnerPath,
+      installPrometheusEndpoint: installPrometheusPath,
     });
 
     this.toggle = this.toggle.bind(this);

app/assets/javascripts/clusters/components/applications.vue

@@ -67,6 +67,16 @@ export default {
         and send the results back to GitLab.`,
       ));
     },
+    prometheusDescription() {
+      return sprintf(
+        _.escape(s__('ClusterIntegration|Prometheus is an open-source monitoring system with %{gitlabIntegrationLink} to monitor deployed applications.')), {
+          gitlabIntegrationLink: `<a href="https://docs.gitlab.com/ce/user/project/integrations/prometheus.html", target="_blank" rel="noopener noreferrer">
+            ${_.escape(s__('ClusterIntegration|Gitlab Integration'))}
+          </a>`,
+        },
+        false,
+      );
+    },
   },
 };
 </script>
@@ -105,6 +115,16 @@ export default {
          :status-reason="applications.ingress.statusReason"
          :request-status="applications.ingress.requestStatus"
          :request-reason="applications.ingress.requestReason"
+       />
+       <application-row
+         id="prometheus"
+         :title="applications.prometheus.title"
+         title-link="https://prometheus.io/docs/introduction/overview/"
+         :description="prometheusDescription"
+         :status="applications.prometheus.status"
+         :status-reason="applications.prometheus.statusReason"
+         :request-status="applications.prometheus.requestStatus"
+         :request-reason="applications.prometheus.requestReason"
        />
         <!-- NOTE: Don't forget to update `clusters.scss` min-height for this block and uncomment `application_spec` tests -->
         <!-- Add GitLab Runner row, all other plumbing is complete -->

app/assets/javascripts/clusters/services/clusters_service.js

@@ -7,6 +7,7 @@ export default class ClusterService {
       helm: this.options.installHelmEndpoint,
       ingress: this.options.installIngressEndpoint,
       runner: this.options.installRunnerEndpoint,
+      prometheus: this.options.installPrometheusEndpoint,
     };
   }
 

app/assets/javascripts/clusters/stores/clusters_store.js

@@ -28,6 +28,13 @@ export default class ClusterStore {
           requestStatus: null,
           requestReason: null,
         },
+        prometheus: {
+          title: s__('ClusterIntegration|Prometheus'),
+          status: null,
+          statusReason: null,
+          requestStatus: null,
+          requestReason: null,
+        },
       },
     };
   }

app/assets/stylesheets/pages/clusters.scss

@@ -6,7 +6,7 @@
 
 .cluster-applications-table {
   // Wait for the Vue to kick-in and render the applications block
-  min-height: 302px;
+  min-height: 400px;
 }
 
 .clusters-dropdown-menu {

app/models/clusters/applications/helm.rb

@@ -3,32 +3,19 @@ module Applications
     class Helm < ActiveRecord::Base
       self.table_name = 'clusters_applications_helm'
 
+      include ::Clusters::Concerns::ApplicationCore
       include ::Clusters::Concerns::ApplicationStatus
 
-      belongs_to :cluster, class_name: 'Clusters::Cluster', foreign_key: :cluster_id
-
       default_value_for :version, Gitlab::Kubernetes::Helm::HELM_VERSION
 
-      validates :cluster, presence: true
-
-      after_initialize :set_initial_status
-
-      def self.application_name
-        self.to_s.demodulize.underscore
-      end
-
       def set_initial_status
         return unless not_installable?
 
         self.status = 'installable' if cluster&.platform_kubernetes_active?
       end
 
-      def name
-        self.class.application_name
-      end
-
       def install_command
-        Gitlab::Kubernetes::Helm::InstallCommand.new(name, true)
+        Gitlab::Kubernetes::Helm::InstallCommand.new(name, install_helm: true)
       end
     end
   end

app/models/clusters/applications/ingress.rb

@@ -3,41 +3,22 @@ module Applications
     class Ingress < ActiveRecord::Base
       self.table_name = 'clusters_applications_ingress'
 
+      include ::Clusters::Concerns::ApplicationCore
       include ::Clusters::Concerns::ApplicationStatus
 
-      belongs_to :cluster, class_name: 'Clusters::Cluster', foreign_key: :cluster_id
-
-      validates :cluster, presence: true
-
       default_value_for :ingress_type, :nginx
       default_value_for :version, :nginx
 
-      after_initialize :set_initial_status
-
       enum ingress_type: {
         nginx: 1
       }
 
-      def self.application_name
-        self.to_s.demodulize.underscore
-      end
-
-      def set_initial_status
-        return unless not_installable?
-
-        self.status = 'installable' if cluster&.application_helm_installed?
-      end
-
-      def name
-        self.class.application_name
-      end
-
       def chart
         'stable/nginx-ingress'
       end
 
       def install_command
-        Gitlab::Kubernetes::Helm::InstallCommand.new(name, false, chart)
+        Gitlab::Kubernetes::Helm::InstallCommand.new(name, chart: chart)
       end
     end
   end

app/models/clusters/applications/prometheus.rb

+module Clusters
+  module Applications
+    class Prometheus < ActiveRecord::Base
+      VERSION = "2.0.0".freeze
+
+      self.table_name = 'clusters_applications_prometheus'
+
+      include ::Clusters::Concerns::ApplicationCore
+      include ::Clusters::Concerns::ApplicationStatus
+
+      default_value_for :version, VERSION
+
+      def chart
+        'stable/prometheus'
+      end
+
+      def chart_values_file
+        "#{Rails.root}/vendor/#{name}/values.yaml"
+      end
+
+      def install_command
+        Gitlab::Kubernetes::Helm::InstallCommand.new(name, chart: chart, chart_values_file: chart_values_file)
+      end
+    end
+  end
+end

app/models/clusters/cluster.rb

@@ -6,7 +6,8 @@ class Cluster < ActiveRecord::Base
 
     APPLICATIONS = {
       Applications::Helm.application_name => Applications::Helm,
-      Applications::Ingress.application_name => Applications::Ingress
+      Applications::Ingress.application_name => Applications::Ingress,
+      Applications::Prometheus.application_name => Applications::Prometheus
     }.freeze
 
     belongs_to :user
@@ -21,6 +22,7 @@ class Cluster < ActiveRecord::Base
 
     has_one :application_helm, class_name: 'Clusters::Applications::Helm'
     has_one :application_ingress, class_name: 'Clusters::Applications::Ingress'
+    has_one :application_prometheus, class_name: 'Clusters::Applications::Prometheus'
 
     accepts_nested_attributes_for :provider_gcp, update_only: true
     accepts_nested_attributes_for :platform_kubernetes, update_only: true
@@ -62,7 +64,8 @@ def created?
     def applications
       [
         application_helm || build_application_helm,
-        application_ingress || build_application_ingress
+        application_ingress || build_application_ingress,
+        application_prometheus || build_application_prometheus
       ]
     end
 

app/models/clusters/concerns/application_core.rb

+module Clusters
+  module Concerns
+    module ApplicationCore
+      extend ActiveSupport::Concern
+
+      included do
+        belongs_to :cluster, class_name: 'Clusters::Cluster', foreign_key: :cluster_id
+
+        validates :cluster, presence: true
+
+        after_initialize :set_initial_status
+
+        def set_initial_status
+          return unless not_installable?
+
+          self.status = 'installable' if cluster&.application_helm_installed?
+        end
+
+        def self.application_name
+          self.to_s.demodulize.underscore
+        end
+
+        def name
+          self.class.application_name
+        end
+      end
+    end
+  end
+end

app/services/clusters/applications/base_helm_service.rb

@@ -18,7 +18,7 @@ def kubeclient
       end
 
       def helm_api
-        @helm_api ||= Gitlab::Kubernetes::Helm.new(kubeclient)
+        @helm_api ||= Gitlab::Kubernetes::Helm::Api.new(kubeclient)
       end
 
       def install_command

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

@@ -9,6 +9,7 @@
 .edit-cluster-form.js-edit-cluster-form{ data: { status_path: status_path,
   install_helm_path: install_applications_namespace_project_cluster_path(@cluster.project.namespace, @cluster.project, @cluster, :helm),
   install_ingress_path: install_applications_namespace_project_cluster_path(@cluster.project.namespace, @cluster.project, @cluster, :ingress),
+  install_prometheus_path: install_applications_namespace_project_cluster_path(@cluster.project.namespace, @cluster.project, @cluster, :prometheus),
   toggle_status: @cluster.enabled? ? 'true': 'false',
   cluster_status: @cluster.status_name,
   cluster_status_reason: @cluster.status_reason,

changelogs/unreleased/41053-extend-cluster-applications-to-allow-install-to-prometheus.yml

+---
+title: Add Prometheus to available Cluster applications
+merge_request: 15895
+author:
+type: added

db/migrate/20171212203433_create_clusters_applications_prometheus.rb

+class CreateClustersApplicationsPrometheus < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    create_table :clusters_applications_prometheus do |t|
+      t.references :cluster, null: false, unique: true, foreign_key: { on_delete: :cascade }
+
+      t.integer :status, null: false
+      t.string :version, null: false
+
+      t.text :status_reason
+
+      t.timestamps_with_timezone null: false
+    end
+  end
+end

db/schema.rb

@@ -568,6 +568,15 @@
     t.text "status_reason"
   end
 
+  create_table "clusters_applications_prometheus", force: :cascade do |t|
+    t.integer "cluster_id", null: false
+    t.integer "status", null: false
+    t.string "version", null: false
+    t.text "status_reason"
+    t.datetime_with_timezone "created_at", null: false
+    t.datetime_with_timezone "updated_at", null: false
+  end
+
   create_table "container_repositories", force: :cascade do |t|
     t.integer "project_id", null: false
     t.string "name", null: false

lib/gitlab/kubernetes/helm.rb

 module Gitlab
   module Kubernetes
-    class Helm
+    module Helm
       HELM_VERSION = '2.7.0'.freeze
       NAMESPACE = 'gitlab-managed-apps'.freeze
-      INSTALL_DEPS = <<-EOS.freeze
-        set -eo pipefail
-        apk add -U ca-certificates openssl >/dev/null
-        wget -q -O - https://kubernetes-helm.storage.googleapis.com/helm-v${HELM_VERSION}-linux-amd64.tar.gz | tar zxC /tmp >/dev/null
-        mv /tmp/linux-amd64/helm /usr/bin/
-      EOS
-
-      InstallCommand = Struct.new(:name, :install_helm, :chart) do
-        def pod_name
-          "install-#{name}"
-        end
-      end
-
-      def initialize(kubeclient)
-        @kubeclient = kubeclient
-        @namespace = Gitlab::Kubernetes::Namespace.new(NAMESPACE, kubeclient)
-      end
-
-      def install(command)
-        @namespace.ensure_exists!
-        @kubeclient.create_pod(pod_resource(command))
-      end
-
-      ##
-      # Returns Pod phase
-      #
-      # https://kubernetes.io/docs/concepts/workloads/pods/pod-lifecycle/#pod-phase
-      #
-      # values: "Pending", "Running", "Succeeded", "Failed", "Unknown"
-      #
-      def installation_status(pod_name)
-        @kubeclient.get_pod(pod_name, @namespace.name).status.phase
-      end
-
-      def installation_log(pod_name)
-        @kubeclient.get_pod_log(pod_name, @namespace.name).body
-      end
-
-      def delete_installation_pod!(pod_name)
-        @kubeclient.delete_pod(pod_name, @namespace.name)
-      end
-
-      private
-
-      def pod_resource(command)
-        labels = { 'gitlab.org/action': 'install', 'gitlab.org/application': command.name }
-        metadata = { name: command.pod_name, namespace: @namespace.name, labels: labels }
-        container = {
-          name: 'helm',
-          image: 'alpine:3.6',
-          env: generate_pod_env(command),
-          command: %w(/bin/sh),
-          args: %w(-c $(COMMAND_SCRIPT))
-        }
-        spec = { containers: [container], restartPolicy: 'Never' }
-
-        ::Kubeclient::Resource.new(metadata: metadata, spec: spec)
-      end
-
-      def generate_pod_env(command)
-        {
-          HELM_VERSION: HELM_VERSION,
-          TILLER_NAMESPACE: @namespace.name,
-          COMMAND_SCRIPT: generate_script(command)
-        }.map { |key, value| { name: key, value: value } }
-      end
-
-      def generate_script(command)
-        [
-            INSTALL_DEPS,
-            helm_init_command(command),
-            helm_install_command(command)
-        ].join("\n")
-      end
-
-      def helm_init_command(command)
-        if command.install_helm
-          'helm init >/dev/null'
-        else
-          'helm init --client-only >/dev/null'
-        end
-      end
-
-      def helm_install_command(command)
-        return if command.chart.nil?
-
-        "helm install #{command.chart} --name #{command.name} --namespace #{@namespace.name} >/dev/null"
-      end
     end
   end
 end

lib/gitlab/kubernetes/helm/api.rb

+module Gitlab
+  module Kubernetes
+    module Helm
+      class Api
+        def initialize(kubeclient)
+          @kubeclient = kubeclient
+          @namespace = Gitlab::Kubernetes::Namespace.new(Gitlab::Kubernetes::Helm::NAMESPACE, kubeclient)
+        end
+
+        def install(command)
+          @namespace.ensure_exists!
+          @kubeclient.create_pod(pod_resource(command))
+        end
+
+        ##
+        # Returns Pod phase
+        #
+        # https://kubernetes.io/docs/concepts/workloads/pods/pod-lifecycle/#pod-phase
+        #
+        # values: "Pending", "Running", "Succeeded", "Failed", "Unknown"
+        #
+        def installation_status(pod_name)
+          @kubeclient.get_pod(pod_name, @namespace.name).status.phase
+        end
+
+        def installation_log(pod_name)
+          @kubeclient.get_pod_log(pod_name, @namespace.name).body
+        end
+
+        def delete_installation_pod!(pod_name)
+          @kubeclient.delete_pod(pod_name, @namespace.name)
+        end
+
+        private
+
+        def pod_resource(command)
+          Pod.new(command, @namespace.name, @kubeclient).generate
+        end
+      end
+    end
+  end
+end

lib/gitlab/kubernetes/helm/install_command.rb

+module Gitlab
+  module Kubernetes
+    module Helm
+      class InstallCommand
+        attr_reader :name, :install_helm, :chart, :chart_values_file
+
+        def initialize(name, install_helm: false, chart: false, chart_values_file: false)
+          @name = name
+          @install_helm = install_helm
+          @chart = chart
+          @chart_values_file = chart_values_file
+        end
+
+        def pod_name
+          "install-#{name}"
+        end
+
+        def generate_script(namespace_name)
+          [
+            install_dps_command,
+            init_command,
+            complete_command(namespace_name)
+          ].join("\n")
+        end
+
+        private
+
+        def init_command
+          if install_helm
+            'helm init >/dev/null'
+          else
+            'helm init --client-only >/dev/null'
+          end
+        end
+
+        def complete_command(namespace_name)
+          return unless chart
+
+          "helm install #{chart} --name #{name} --namespace #{namespace_name} >/dev/null"
+        end
+
+        def install_dps_command
+          <<~HEREDOC
+            set -eo pipefail
+            apk add -U ca-certificates openssl >/dev/null
+            wget -q -O - https://kubernetes-helm.storage.googleapis.com/helm-v#{Gitlab::Kubernetes::Helm::HELM_VERSION}-linux-amd64.tar.gz | tar zxC /tmp >/dev/null
+            mv /tmp/linux-amd64/helm /usr/bin/
+          HEREDOC
+        end
+      end
+    end
+  end
+end

lib/gitlab/kubernetes/helm/pod.rb

+module Gitlab
+  module Kubernetes
+    module Helm
+      class Pod
+        def initialize(command, namespace_name, kubeclient)
+          @command = command
+          @namespace_name = namespace_name
+          @kubeclient = kubeclient
+        end
+
+        def generate
+          spec = { containers: [container_specification], restartPolicy: 'Never' }
+          if command.chart_values_file
+            generate_config_map
+            spec['volumes'] = volumes_specification
+          end
+          ::Kubeclient::Resource.new(metadata: metadata, spec: spec)
+        end
+
+        private
+
+        attr_reader :command, :namespace_name, :kubeclient
+
+        def container_specification
+          container = {
+            name: 'helm',
+            image: 'alpine:3.6',
+            env: generate_pod_env(command),
+            command: %w(/bin/sh),
+            args: %w(-c $(COMMAND_SCRIPT))
+          }
+          container[:volumeMounts] = volume_mounts_specification if command.chart_values_file
+          container
+        end
+
+        def labels
+          { 'gitlab.org/action': 'install', 'gitlab.org/application': command.name }
+        end
+
+        def metadata
+          { name: command.pod_name, namespace: namespace_name, labels: labels }
+        end
+
+        def volume_mounts_specification
+          [{ name: 'config-volume', mountPath: '/etc/config' }]
+        end
+
+        def volumes_specification
+          [{ name: 'config-volume', configMap: { name: 'values-config' } }]
+        end
+
+        def generate_pod_env(command)
+          {
+            HELM_VERSION: Gitlab::Kubernetes::Helm::HELM_VERSION,
+            TILLER_NAMESPACE: namespace_name,
+            COMMAND_SCRIPT: command.generate_script(namespace_name)
+          }.map { |key, value| { name: key, value: value } }
+        end
+
+        def generate_config_map
+          resource = ::Kubeclient::Resource.new
+          resource.metadata = { name: 'values-config', namespace: namespace_name }
+          resource.data = YAML.load_file(command.chart_values_file)
+          kubeclient.create_config_map(resource)
+        end
+      end
+    end
+  end
+end

spec/controllers/projects/clusters/applications_controller_spec.rb

@@ -52,7 +52,7 @@ def current_application
 
       context 'when application is already installing' do
         before do
-          create(:cluster_applications_helm, :installing, cluster: cluster)
+          create(:clusters_applications_helm, :installing, cluster: cluster)
         end
 
         it 'returns 400' do

spec/factories/clusters/applications/helm.rb

 FactoryBot.define do
-  factory :cluster_applications_helm, class: Clusters::Applications::Helm do
+  factory :clusters_applications_helm, class: Clusters::Applications::Helm do
     cluster factory: %i(cluster provided_by_gcp)
 
     trait :not_installable do
@@ -31,5 +31,8 @@
       installing
       updated_at ClusterWaitForAppInstallationWorker::TIMEOUT.ago
     end
+
+    factory :clusters_applications_ingress, class: Clusters::Applications::Ingress
+    factory :clusters_applications_prometheus, class: Clusters::Applications::Prometheus
   end
 end

spec/factories/clusters/applications/ingress.rb

-FactoryBot.define do
-  factory :cluster_applications_ingress, class: Clusters::Applications::Ingress do
-    cluster factory: %i(cluster provided_by_gcp)
-
-    trait :not_installable do
-      status(-2)
-    end
-
-    trait :installable do
-      status 0
-    end
-
-    trait :scheduled do
-      status 1
-    end
-
-    trait :installing do
-      status 2
-    end
-