Extend Cluster Applications to allow installation of Prometheus

4 files changed, 165 insertions, 89 deletions

diff --git a/lib/gitlab/kubernetes/helm.rb b/lib/gitlab/kubernetes/helm.rb
index 407cdefc04d..0f0588b8b23 100644
--- a/lib/gitlab/kubernetes/helm.rb
+++ b/lib/gitlab/kubernetes/helm.rb
@@ -1,96 +1,8 @@
 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
diff --git a/lib/gitlab/kubernetes/helm/api.rb b/lib/gitlab/kubernetes/helm/api.rb
new file mode 100644
index 00000000000..ebd7dc1b100
--- /dev/null
+++ b/lib/gitlab/kubernetes/helm/api.rb
@@ -0,0 +1,42 @@
+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
diff --git a/lib/gitlab/kubernetes/helm/install_command.rb b/lib/gitlab/kubernetes/helm/install_command.rb
new file mode 100644
index 00000000000..8d8c441a4b1
--- /dev/null
+++ b/lib/gitlab/kubernetes/helm/install_command.rb
@@ -0,0 +1,53 @@
+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
diff --git a/lib/gitlab/kubernetes/helm/pod.rb b/lib/gitlab/kubernetes/helm/pod.rb
new file mode 100644
index 00000000000..233f6bf6227
--- /dev/null
+++ b/lib/gitlab/kubernetes/helm/pod.rb
@@ -0,0 +1,69 @@
+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