Install k8s application with helm running inside the cluster

13 files changed, 223 insertions, 0 deletions

diff --git a/app/models/clusters/concerns.rb b/app/models/clusters/concerns.rb
new file mode 100644
index 00000000000..cd09863bcfc
--- /dev/null
+++ b/app/models/clusters/concerns.rb
@@ -0,0 +1,4 @@
+module Clusters
+  module Concerns
+  end
+end
diff --git a/app/models/clusters/concerns/app_status.rb b/app/models/clusters/concerns/app_status.rb
new file mode 100644
index 00000000000..f6b817e9ce7
--- /dev/null
+++ b/app/models/clusters/concerns/app_status.rb
@@ -0,0 +1,33 @@
+module Clusters
+  module Concerns
+    module AppStatus
+      extend ActiveSupport::Concern
+
+      included do
+        state_machine :status, initial: :scheduled do
+          state :errored, value: -1
+          state :scheduled, value: 0
+          state :installing, value: 1
+          state :installed, value: 2
+
+          event :make_installing do
+            transition any - [:installing] => :installing
+          end
+
+          event :make_installed do
+            transition any - [:installed] => :installed
+          end
+
+          event :make_errored do
+            transition any - [:errored] => :errored
+          end
+
+          before_transition any => [:errored] do |app_status, transition|
+            status_reason = transition.args.first
+            app_status.status_reason = status_reason if status_reason
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/app/models/clusters/kubernetes.rb b/app/models/clusters/kubernetes.rb
new file mode 100644
index 00000000000..b68e2ae401e
--- /dev/null
+++ b/app/models/clusters/kubernetes.rb
@@ -0,0 +1,16 @@
+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/kubernetes/helm_app.rb b/app/models/clusters/kubernetes/helm_app.rb
new file mode 100644
index 00000000000..32c9e13a469
--- /dev/null
+++ b/app/models/clusters/kubernetes/helm_app.rb
@@ -0,0 +1,18 @@
+module Clusters
+  module Kubernetes
+    class HelmApp < ActiveRecord::Base
+      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
+
+      alias_method :cluster, :kubernetes_service
+
+      def name
+        NAME
+      end
+    end
+  end
+end
diff --git a/app/models/project_services/kubernetes_service.rb b/app/models/project_services/kubernetes_service.rb
index 8ba07173c74..4b754b4d3ce 100644
--- a/app/models/project_services/kubernetes_service.rb
+++ b/app/models/project_services/kubernetes_service.rb
@@ -3,6 +3,8 @@ 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
@@ -136,6 +138,10 @@ class KubernetesService < DeploymentService
     { pods: read_pods }
   end
 
+  def helm
+    Gitlab::Clusters::Helm.new(build_kubeclient!)
+  end
+
   TEMPLATE_PLACEHOLDER = 'Kubernetes namespace'.freeze
 
   private
diff --git a/app/services/clusters/base_helm_service.rb b/app/services/clusters/base_helm_service.rb
new file mode 100644
index 00000000000..b8ed52bf376
--- /dev/null
+++ b/app/services/clusters/base_helm_service.rb
@@ -0,0 +1,17 @@
+module Clusters
+  class BaseHelmService
+    attr_accessor :app
+
+    def initialize(app)
+      @app = app
+    end
+
+    protected
+
+    def helm
+      return @helm if defined?(@helm)
+
+      @helm = @app.cluster.helm
+    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
new file mode 100644
index 00000000000..e21aa49bb43
--- /dev/null
+++ b/app/services/clusters/fetch_app_installation_status_service.rb
@@ -0,0 +1,13 @@
+module Clusters
+  class FetchAppInstallationStatusService < BaseHelmService
+    def execute
+      return unless app.installing?
+
+      phase = helm.installation_status(app)
+      log = helm.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?
+    end
+  end
+end
diff --git a/app/services/clusters/finalize_app_installation_service.rb b/app/services/clusters/finalize_app_installation_service.rb
new file mode 100644
index 00000000000..c921747febc
--- /dev/null
+++ b/app/services/clusters/finalize_app_installation_service.rb
@@ -0,0 +1,15 @@
+module Clusters
+  class FinalizeAppInstallationService < BaseHelmService
+    def execute
+      helm.delete_installation_pod!(app)
+
+      app.make_errored!('Installation aborted') if aborted?
+    end
+
+    private
+
+    def aborted?
+      app.installing? || app.scheduled?
+    end
+  end
+end
diff --git a/app/services/clusters/install_app_service.rb b/app/services/clusters/install_app_service.rb
new file mode 100644
index 00000000000..dd8556108d4
--- /dev/null
+++ b/app/services/clusters/install_app_service.rb
@@ -0,0 +1,23 @@
+module Clusters
+  class InstallAppService < BaseHelmService
+    def execute
+      return unless app.scheduled?
+
+      begin
+        helm.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
+        Rails.logger.warn(e.message)
+        app.make_errored!("Can't start installation process")
+      end
+    end
+  end
+end
diff --git a/app/services/clusters/install_tiller_service.rb b/app/services/clusters/install_tiller_service.rb
new file mode 100644
index 00000000000..ac77a7ea3c2
--- /dev/null
+++ b/app/services/clusters/install_tiller_service.rb
@@ -0,0 +1,24 @@
+module Clusters
+  class InstallTillerService < BaseService
+    def execute
+      ensure_namespace
+      install
+    end
+
+    private
+
+    def kubernetes_service
+      return @kubernetes_service if defined?(@kubernetes_service)
+
+      @kubernetes_service = project&.kubernetes_service
+    end
+
+    def ensure_namespace
+      kubernetes_service&.ensure_namespace!
+    end
+
+    def install
+      kubernetes_service&.helm_client&.init!
+    end
+  end
+end
diff --git a/app/workers/cluster_install_app_worker.rb b/app/workers/cluster_install_app_worker.rb
new file mode 100644
index 00000000000..4993b2b7349
--- /dev/null
+++ b/app/workers/cluster_install_app_worker.rb
@@ -0,0 +1,11 @@
+class ClusterInstallAppWorker
+  include Sidekiq::Worker
+  include ClusterQueue
+  include ClusterApp
+
+  def perform(app_name, app_id)
+    find_app(app_name, app_id) do |app|
+      Clusters::InstallAppService.new(app).execute
+    end
+  end
+end
diff --git a/app/workers/cluster_wait_for_app_installation_worker.rb b/app/workers/cluster_wait_for_app_installation_worker.rb
new file mode 100644
index 00000000000..21149cf2d19
--- /dev/null
+++ b/app/workers/cluster_wait_for_app_installation_worker.rb
@@ -0,0 +1,33 @@
+class ClusterWaitForAppInstallationWorker
+  include Sidekiq::Worker
+  include ClusterQueue
+  include ClusterApp
+
+  INITIAL_INTERVAL = 30.seconds
+  EAGER_INTERVAL = 10.seconds
+  TIMEOUT = 20.minutes
+
+  def perform(app_name, app_id)
+    find_app(app_name, app_id) do |app|
+      Clusters::FetchAppInstallationStatusService.new(app).execute do |phase, log|
+        case phase
+        when 'Succeeded'
+          if app.make_installed
+            Clusters::FinalizeAppInstallationService.new(app).execute
+          else
+            app.make_errored!("Failed to update app record; #{app.errors}")
+          end
+        when 'Failed'
+          app.make_errored!(log || 'Installation silently failed')
+          Clusters::FinalizeAppInstallationService.new(app).execute
+        else
+          if Time.now.utc - app.updated_at.to_time.utc > TIMEOUT
+            app.make_errored!('App installation timeouted')
+          else
+            ClusterWaitForAppInstallationWorker.perform_in(EAGER_INTERVAL, app.name, app.id)
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/app/workers/concerns/cluster_app.rb b/app/workers/concerns/cluster_app.rb
new file mode 100644
index 00000000000..2170f8be6f6
--- /dev/null
+++ b/app/workers/concerns/cluster_app.rb
@@ -0,0 +1,10 @@
+module ClusterApp
+  extend ActiveSupport::Concern
+
+  included do
+    def find_app(app_name, id)
+      app = Clusters::Kubernetes.app(app_name).find(id)
+      yield(app) if block_given?
+    end
+  end
+end