15 files changed, 99 insertions, 48 deletions

diff --git a/app/controllers/projects/clusters/applications_controller.rb b/app/controllers/projects/clusters/applications_controller.rb
new file mode 100644
index 00000000000..438e1853435
--- /dev/null
+++ b/app/controllers/projects/clusters/applications_controller.rb
@@ -0,0 +1,39 @@
+class Projects::Clusters::ApplicationsController < Projects::ApplicationController
+  before_action :cluster
+  before_action :application_class, only: [:create]
+  before_action :authorize_read_cluster!
+  before_action :authorize_create_cluster!, only: [:create]
+
+  def new
+  end
+
+  def create
+    return render_404 if application
+
+    new_application = application_class.create(cluster: cluster)
+
+    respond_to do |format|
+      format.json do
+        if new_application.persisted?
+          head :ok
+        else
+          head :bad_request
+        end
+      end
+    end
+  end
+
+  private
+
+  def cluster
+    @cluster ||= project.clusters.find_by(cluster_id: params[:cluster_id]).present(current_user: current_user)
+  end
+
+  def application_class
+    Clusters::Cluster::Applications.find(params[:application])
+  end
+
+  def application
+    application_class.find_by(cluster: cluster)
+  end
+end
diff --git a/app/models/clusters/kubernetes/helm_app.rb b/app/models/clusters/applications/helm.rb
index 32c9e13a469..59e0076c8df 100644
--- a/app/models/clusters/kubernetes/helm_app.rb
+++ b/app/models/clusters/applications/helm.rb
@@ -1,14 +1,15 @@
 module Clusters
-  module Kubernetes
-    class HelmApp < ActiveRecord::Base
+  module Applications
+    class Helm < ActiveRecord::Base
+      self.table_name = 'clusters_applications_helm'
+
       NAME = 'helm'.freeze
 
       include ::Clusters::Concerns::AppStatus
-      belongs_to :kubernetes_service, class_name: 'KubernetesService', foreign_key: :service_id
 
-      default_value_for :version, Gitlab::Clusters::Helm::HELM_VERSION
+      belongs_to :cluser, class_name: 'Clusters::Cluster', foreign_key: :cluster_id
 
-      alias_method :cluster, :kubernetes_service
+      default_value_for :version, Gitlab::Clusters::Helm::HELM_VERSION
 
       def name
         NAME
diff --git a/app/models/clusters/cluster.rb b/app/models/clusters/cluster.rb
index ca09b939f34..c814f475adf 100644
--- a/app/models/clusters/cluster.rb
+++ b/app/models/clusters/cluster.rb
@@ -4,6 +4,10 @@ module Clusters
 
     self.table_name = 'clusters'
 
+    APPLICATIONS = {
+      Clusters::Applications::Helm::NAME => Clusters::Applications::Helm
+    }
+
     belongs_to :user
 
     has_many :cluster_projects, class_name: 'Clusters::Project'
@@ -15,13 +19,14 @@ module Clusters
     # We have to ":destroy" it today to ensure that we clean also the Kubernetes Integration
     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'
+
     accepts_nested_attributes_for :provider_gcp, update_only: true
     accepts_nested_attributes_for :platform_kubernetes, update_only: true
 
     validates :name, cluster_name: true
     validate :restrict_modification, on: :update
 
-    delegate :status, to: :provider, allow_nil: true
     delegate :status_reason, to: :provider, allow_nil: true
     delegate :status_name, to: :provider, allow_nil: true
     delegate :on_creation?, to: :provider, allow_nil: true
@@ -38,6 +43,14 @@ module Clusters
     scope :enabled, -> { where(enabled: true) }
     scope :disabled, -> { where(enabled: false) }
 
+    def status_name
+      if provider
+        provider.status_name
+      else
+        :created
+      end
+    end
+
     def provider
       return provider_gcp if gcp?
     end
@@ -53,6 +66,10 @@ module Clusters
     end
     alias_method :project, :first_project
 
+    def kubeclient
+      platform_kubernetes.kubeclient if kubernetes?
+    end
+
     private
 
     def restrict_modification
diff --git a/app/models/clusters/kubernetes.rb b/app/models/clusters/kubernetes.rb
deleted file mode 100644
index b68e2ae401e..00000000000
--- a/app/models/clusters/kubernetes.rb
+++ /dev/null
@@ -1,16 +0,0 @@
-module Clusters
-  module Kubernetes
-    def self.table_name_prefix
-      'clusters_kubernetes_'
-    end
-
-    def self.app(app_name)
-      case app_name
-      when HelmApp::NAME
-        HelmApp
-      else
-        raise ArgumentError, "Unknown app #{app_name}"
-      end
-    end
-  end
-end
diff --git a/app/models/clusters/platforms/kubernetes.rb b/app/models/clusters/platforms/kubernetes.rb
index 3ad2ffe531d..1197dfaefcb 100644
--- a/app/models/clusters/platforms/kubernetes.rb
+++ b/app/models/clusters/platforms/kubernetes.rb
@@ -60,6 +60,10 @@ module Clusters
         self.class.namespace_for_project(project) if project
       end
 
+      def kubeclient
+        @kubeclient ||= kubernetes_service.kubeclient if manages_kubernetes_service?
+      end
+
       private
 
       def enforce_namespace_to_lower_case
diff --git a/app/models/project.rb b/app/models/project.rb
index d9d9e12c947..a42e2553935 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -189,6 +189,7 @@ class Project < ActiveRecord::Base
 
   has_one :cluster_project, class_name: 'Clusters::Project'
   has_one :cluster, through: :cluster_project, class_name: 'Clusters::Cluster'
+  has_many :clusters, through: :cluster_project, class_name: 'Clusters::Cluster'
 
   # Container repositories need to remove data from the container registry,
   # which is not managed by the DB. Hence we're still using dependent: :destroy
diff --git a/app/models/project_services/kubernetes_service.rb b/app/models/project_services/kubernetes_service.rb
index b4654e8d1ea..5080acffb3c 100644
--- a/app/models/project_services/kubernetes_service.rb
+++ b/app/models/project_services/kubernetes_service.rb
@@ -3,8 +3,6 @@ class KubernetesService < DeploymentService
   include Gitlab::Kubernetes
   include ReactiveCaching
 
-  has_one :helm_app, class_name: 'Clusters::Kubernetes::HelmApp', foreign_key: :service_id
-
   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
@@ -138,8 +136,8 @@ class KubernetesService < DeploymentService
     { pods: read_pods }
   end
 
-  def helm
-    Gitlab::Clusters::Helm.new(build_kubeclient!)
+  def kubeclient
+    @kubeclient ||= build_kubeclient!
   end
 
   TEMPLATE_PLACEHOLDER = 'Kubernetes namespace'.freeze
diff --git a/app/presenters/clusters/cluster_presenter.rb b/app/presenters/clusters/cluster_presenter.rb
index 01cb59d0d44..5e11dac3bd2 100644
--- a/app/presenters/clusters/cluster_presenter.rb
+++ b/app/presenters/clusters/cluster_presenter.rb
@@ -5,5 +5,11 @@ module Clusters
     def gke_cluster_url
       "https://console.cloud.google.com/kubernetes/clusters/details/#{provider.zone}/#{name}" if gcp?
     end
+
+    def applications
+      Clusters::Cluster::APPLICATIONS.map do |key, value|
+        value.find_by(cluster_id: id)
+      end.compact
+    end
   end
 end
diff --git a/app/serializers/cluster_app_entity.rb b/app/serializers/cluster_app_entity.rb
new file mode 100644
index 00000000000..7da2d4921a2
--- /dev/null
+++ b/app/serializers/cluster_app_entity.rb
@@ -0,0 +1,5 @@
+class ClusterAppEntity < Grape::Entity
+  expose :name
+  expose :status_name, as: :status
+  expose :status_reason
+end
diff --git a/app/serializers/cluster_entity.rb b/app/serializers/cluster_entity.rb
index 84ce34afb32..e775c68eb6b 100644
--- a/app/serializers/cluster_entity.rb
+++ b/app/serializers/cluster_entity.rb
@@ -3,16 +3,5 @@ class ClusterEntity < Grape::Entity
 
   expose :status_name, as: :status
   expose :status_reason
-  expose :applications do |cluster, options|
-    if cluster.created?
-      {
-        helm: { status: 'installed' },
-        ingress: { status: 'error', status_reason: 'Missing namespace' },
-        runner: { status: 'installing' },
-        prometheus: { status: 'installable' }
-      }
-    else
-      {}
-    end
-  end
+  expose :applications, using: ClusterAppEntity
 end
diff --git a/app/services/clusters/base_helm_service.rb b/app/services/clusters/base_helm_service.rb
index b8ed52bf376..c7f7e2d0877 100644
--- a/app/services/clusters/base_helm_service.rb
+++ b/app/services/clusters/base_helm_service.rb
@@ -8,10 +8,16 @@ module Clusters
 
     protected
 
-    def helm
-      return @helm if defined?(@helm)
+    def cluster
+      app.cluster
+    end
+
+    def kubeclient
+      cluster.kubeclient
+    end
 
-      @helm = @app.cluster.helm
+    def helm_api
+      @helm ||= Gitlab::Clusters::Helm.new(kubeclient)
     end
   end
 end
diff --git a/app/services/clusters/fetch_app_installation_status_service.rb b/app/services/clusters/fetch_app_installation_status_service.rb
index e21aa49bb43..9b281c77c49 100644
--- a/app/services/clusters/fetch_app_installation_status_service.rb
+++ b/app/services/clusters/fetch_app_installation_status_service.rb
@@ -3,8 +3,8 @@ module Clusters
     def execute
       return unless app.installing?
 
-      phase = helm.installation_status(app)
-      log = helm.installation_log(app) if phase == 'Failed'
+      phase = helm_api.installation_status(app)
+      log = helm_api.installation_log(app) if phase == 'Failed'
       yield(phase, log) if block_given?
     rescue KubeException => ke
       app.make_errored!("Kubernetes error: #{ke.message}") unless app.errored?
diff --git a/app/services/clusters/finalize_app_installation_service.rb b/app/services/clusters/finalize_app_installation_service.rb
index c921747febc..b9d5da063eb 100644
--- a/app/services/clusters/finalize_app_installation_service.rb
+++ b/app/services/clusters/finalize_app_installation_service.rb
@@ -1,7 +1,7 @@
 module Clusters
   class FinalizeAppInstallationService < BaseHelmService
     def execute
-      helm.delete_installation_pod!(app)
+      helm_api.delete_installation_pod!(app)
 
       app.make_errored!('Installation aborted') if aborted?
     end
diff --git a/app/services/clusters/install_app_service.rb b/app/services/clusters/install_app_service.rb
index dd8556108d4..496af2495fd 100644
--- a/app/services/clusters/install_app_service.rb
+++ b/app/services/clusters/install_app_service.rb
@@ -4,14 +4,14 @@ module Clusters
       return unless app.scheduled?
 
       begin
-        helm.install(app)
+        helm_api.install(app)
+
         if app.make_installing
           ClusterWaitForAppInstallationWorker.perform_in(
             ClusterWaitForAppInstallationWorker::INITIAL_INTERVAL, app.name, app.id)
         else
           app.make_errored!("Failed to update app record; #{app.errors}")
         end
-
       rescue KubeException => ke
         app.make_errored!("Kubernetes error: #{ke.message}")
       rescue StandardError => e
diff --git a/app/workers/concerns/cluster_app.rb b/app/workers/concerns/cluster_app.rb
index 2170f8be6f6..a0202901f15 100644
--- a/app/workers/concerns/cluster_app.rb
+++ b/app/workers/concerns/cluster_app.rb
@@ -3,8 +3,9 @@ module ClusterApp
 
   included do
     def find_app(app_name, id)
-      app = Clusters::Kubernetes.app(app_name).find(id)
-      yield(app) if block_given?
+      Clusters::Applications.const_get(app_name.classify).find(id).try do |app|
+        yield(app) if block_given?
+      end
     end
   end
 end