squash-merge kpack buildpack selection

- Build out KpackLifeCycle and associated validator
- Fetch available buildpacks from k8s and validate availibility in k8s
- using OpenStruct in test to emulate/statisfy duck-typing for the private
    KpackBuildpack class
- constructs custombuilder from default custombuilder on create
- once created, custombuilder updates don't work yet

[#171029528]

Co-authored-by: Sannidhi Jalukar <sjalukar@pivotal.io>
Co-authored-by: Jaskanwal Pawar <jpawar@pivotal.io>
Co-authored-by: Connor Braa <cbraa@pivotal.io>

Author: 3 people

app/actions/app_update.rb

@@ -59,7 +59,7 @@ def custom_buildpacks_disabled?
     def validate_not_changing_lifecycle_type!(app, lifecycle)
       return if app.lifecycle_type == lifecycle.type
 
-      raise InvalidApp.new('Lifecycle type cannot be changed')
+      raise InvalidApp.new("Lifecycle type cannot be changed from #{app.lifecycle_type} to #{lifecycle.type}")
     end
 
     def existing_environment_variables_for(app)

app/messages/app_create_message.rb

@@ -9,15 +9,19 @@ def self.lifecycle_requested?
       @lifecycle_requested ||= proc { |a| a.requested?(:lifecycle) }
     end
 
+    def self.lifecycle_type_requested?
+      @lifecycle_type_requested ||= proc { |a| a.requested?(:lifecycle) && a.lifecycle_type.present? }
+    end
+
     validates_with NoAdditionalKeysValidator, RelationshipValidator
-    validates_with LifecycleValidator, if: lifecycle_requested?
+    validates_with LifecycleValidator, if: lifecycle_type_requested?
 
     validates :name, string: true
     validates :environment_variables, hash: true, allow_nil: true
 
     validates :lifecycle_type,
       string: true,
-      if: lifecycle_requested?
+      if: lifecycle_type_requested?
 
     validates :lifecycle_data,
       hash: true,

app/messages/app_manifest_message.rb

@@ -260,7 +260,6 @@ def buildpacks_lifecycle_data
       end
 
       {
-        type: Lifecycles::BUILDPACK,
         data: {
           buildpacks: requested_buildpacks,
           stack: @stack

app/messages/app_update_message.rb

@@ -11,6 +11,10 @@ def self.lifecycle_requested?
       @lifecycle_requested ||= proc { |a| a.requested?(:lifecycle) }
     end
 
+    def self.lifecycle_type_requested?
+      @lifecycle_type_requested ||= proc { |a| a.requested?(:lifecycle) && a.lifecycle_type.present? }
+    end
+
     validates_with NoAdditionalKeysValidator
     validates_with LifecycleValidator, if: lifecycle_requested?
 
@@ -19,7 +23,7 @@ def self.lifecycle_requested?
     validates :lifecycle_type,
       string: true,
       allow_nil: false,
-      if: lifecycle_requested?
+      if: lifecycle_type_requested?
 
     validates :lifecycle_data,
       hash: true,

app/messages/validators.rb

@@ -160,10 +160,14 @@ def validate(record)
       data_message = {
         VCAP::CloudController::Lifecycles::BUILDPACK => VCAP::CloudController::BuildpackLifecycleDataMessage,
         VCAP::CloudController::Lifecycles::DOCKER => VCAP::CloudController::EmptyLifecycleDataMessage,
-        VCAP::CloudController::Lifecycles::KPACK => VCAP::CloudController::EmptyLifecycleDataMessage,
+        VCAP::CloudController::Lifecycles::KPACK => VCAP::CloudController::BuildpackLifecycleDataMessage,
       }
 
-      lifecycle_data_message_class = data_message[record.lifecycle_type]
+      lifecycle_data_message_class = if record.lifecycle_type.present?
+                                       data_message[record.lifecycle_type]
+                                     else
+                                       VCAP::CloudController::BuildpackLifecycleDataMessage
+                                     end
       if lifecycle_data_message_class.nil?
         record.errors[:lifecycle_type].concat ["is not included in the list: #{data_message.keys.join(', ')}"]
         return

app/models/runtime/kpack_lifecycle_data_model.rb

@@ -2,6 +2,8 @@
 
 module VCAP::CloudController
   class KpackLifecycleDataModel < Sequel::Model(:kpack_lifecycle_data)
+    include Serializer
+
     LIFECYCLE_TYPE = Lifecycles::KPACK
 
     many_to_one :app,
@@ -22,6 +24,9 @@ class KpackLifecycleDataModel < Sequel::Model(:kpack_lifecycle_data)
                 primary_key: :guid,
                 without_guid_generation: true
 
+    # if this gets any thicker, we should model it properly in its own table
+    serializes_via_json :buildpacks
+
     def using_custom_buildpack?
       false
     end
@@ -34,11 +39,13 @@ def first_custom_buildpack_url
       return nil
     end
 
-    def buildpacks
-      []
-    end
+    # def buildpacks=(new_buildpacks) end
 
-    def buildpacks=(new_buildpacks) end
+    def to_hash
+      {
+        buildpacks: buildpacks
+      }
+    end
 
     def stack
       nil

app/models/runtime/kpack_lifecycle_data_model_spec.rb

@@ -0,0 +1,33 @@
+require 'spec_helper'
+
+module VCAP::CloudController
+  RSpec.describe KpackLifecycleDataModel do
+    subject(:lifecycle_data) { KpackLifecycleDataModel.new }
+
+    describe '#to_hash' do
+      let(:expected_lifecycle_data) do
+        { buildpacks: buildpacks || [] }
+      end
+      let(:buildpacks) { [buildpack] }
+      let(:buildpack) { 'ruby' }
+
+      before do
+        Buildpack.make(name: 'ruby')
+        lifecycle_data.buildpacks = buildpacks
+        lifecycle_data.save
+      end
+
+      it 'returns the lifecycle data as a hash' do
+        expect(lifecycle_data.to_hash).to eq expected_lifecycle_data
+      end
+
+      context 'when the user has not specified a buildpack' do
+        let(:buildpacks) { [] }
+
+        it 'returns the lifecycle data as a hash' do
+          expect(lifecycle_data.to_hash).to eq expected_lifecycle_data
+        end
+      end
+    end
+  end
+end

db/migrations/20200727211409_add_kpack_encrypted_buildpack_infos_column.rb

@@ -0,0 +1,7 @@
+Sequel.migration do
+  change do
+    alter_table :kpack_lifecycle_data do
+      add_column :buildpacks, String, size: 5000, default: MultiJson.dump([])
+    end
+  end
+end

lib/cloud_controller/diego/lifecycles/app_kpack_lifecycle.rb

@@ -1,12 +1,24 @@
 module VCAP::CloudController
   class AppKpackLifecycle
-    def initialize(*_message); end
+    def initialize(message)
+      @message = message
+    end
 
     def create_lifecycle_data_model(app)
       app.kpack_lifecycle_data = KpackLifecycleDataModel.create(app: app)
     end
 
-    def update_lifecycle_data_model(_); end
+    def update_lifecycle_data_model(app)
+      if [update_lifecycle_data_buildpacks(app)].any?
+        app.lifecycle_data.save
+      end
+    end
+
+    def update_lifecycle_data_buildpacks(app)
+      if @message.buildpack_data.requested?(:buildpacks)
+        app.lifecycle_data.update(buildpacks: @message.buildpack_data.buildpacks)
+      end
+    end
 
     def valid?
       true

lib/cloud_controller/diego/lifecycles/app_lifecycle_provider.rb

@@ -20,7 +20,7 @@ def self.provide_for_update(message, app)
     end
 
     def self.provide(message, app)
-      type = if message.requested?(:lifecycle)
+      type = if message.lifecycle_type.present?
                message.lifecycle_type
              elsif !app.nil?
                app.lifecycle_type