v3: add clear_buildpack_cache endpoint

`POST /v3/admin/actions/clear_buildpack_cache`

[#163341383]

Co-authored-by: Reid Mitchell <rmitchell@pivotal.io>
Co-authored-by: Belinda Liu <bliu@pivotal.io>

Author: reidmit

app/controllers/v3/admin_actions_controller.rb

@@ -0,0 +1,10 @@
+require 'jobs/v3/buildpack_cache_cleanup'
+
+class AdminActionsController < ApplicationController
+  def clear_buildpack_cache
+    unauthorized! unless permission_queryer.can_write_globally?
+
+    pollable_job = Jobs::Enqueuer.new(Jobs::V3::BuildpackCacheCleanup.new, queue: Jobs::Queues.generic).enqueue_pollable
+    head :accepted, 'Location' => url_builder.build_url(path: "/v3/jobs/#{pollable_job.guid}")
+  end
+end

app/jobs/v3/buildpack_cache_cleanup.rb

@@ -0,0 +1,35 @@
+module VCAP::CloudController
+  module Jobs
+    module V3
+      class BuildpackCacheCleanup < VCAP::CloudController::Jobs::CCJob
+        def perform
+          logger = Steno.logger('cc.background')
+          logger.info('Attempting cleanup of buildpack_cache blobstore')
+
+          blobstore = CloudController::DependencyLocator.instance.buildpack_cache_blobstore
+          blobstore.delete_all
+        end
+
+        def job_name_in_configuration
+          :buildpack_cache_cleanup
+        end
+
+        def display_name
+          'admin.clear_buildpack_cache'
+        end
+
+        def max_attempts
+          3
+        end
+
+        def resource_guid
+          ''
+        end
+
+        def resource_type
+          ''
+        end
+      end
+    end
+  end
+end

app/models/runtime/pollable_job_model.rb

@@ -15,6 +15,8 @@ def complete?
     end
 
     def resource_exists?
+      return false if resource_type.empty?
+
       model = case resource_type
               when 'role'
                 Role
@@ -25,6 +27,7 @@ def resource_exists?
               else
                 Sequel::Model(ActiveSupport::Inflector.pluralize(resource_type).to_sym)
               end
+
       !!model.find(guid: resource_guid)
     end
 

config/routes.rb

@@ -1,6 +1,9 @@
 Rails.application.routes.draw do
   get '/', to: 'root#v3_root'
 
+  # admin actions
+  post '/admin/actions/clear_buildpack_cache', to: 'admin_actions#clear_buildpack_cache'
+
   # apps
   get '/apps', to: 'apps_v3#index'
   post '/apps', to: 'apps_v3#create'

spec/request/admin_actions_spec.rb

@@ -0,0 +1,35 @@
+require 'spec_helper'
+require 'request_spec_shared_examples'
+
+RSpec.describe 'admin actions' do
+  let(:space) { VCAP::CloudController::Space.make }
+  let(:org) { space.organization }
+  let(:user) { VCAP::CloudController::User.make }
+  let(:admin_header) { admin_headers_for(user) }
+
+  describe 'POST /v3/admin/actions/clear_buildpack_cache' do
+    let(:api_call) { lambda { |user_headers| post '/v3/admin/actions/clear_buildpack_cache', {}, user_headers } }
+
+    let(:expected_codes_and_responses) do
+      h = Hash.new(
+        code: 403,
+      )
+      h['admin'] = {
+        code: 202,
+      }
+      h.freeze
+    end
+
+    it_behaves_like 'permissions for single object endpoint', ALL_PERMISSIONS do
+      let(:after_request_check) do
+        lambda do
+          job_guid = last_response.headers['Location'].gsub("#{link_prefix}/v3/jobs/", '')
+          get "/v3/jobs/#{job_guid}", {}, admin_headers
+          expect(last_response).to have_status_code(200)
+
+          execute_all_jobs(expected_successes: 1, expected_failures: 0)
+        end
+      end
+    end
+  end
+end

spec/unit/jobs/v3/buildpack_cache_cleanup_spec.rb

@@ -0,0 +1,84 @@
+require 'spec_helper'
+
+module VCAP::CloudController
+  module Jobs::V3
+    RSpec.describe BuildpackCacheCleanup, job_context: :worker do
+      let(:cc_addr) { '1.2.3.4' }
+      let(:cc_port) { 5678 }
+      let(:orphan_key) { 'orphan-key' }
+      let(:buildpack_cache_key) { 'another-cache-key' }
+      let(:droplet_key) { 'droplet-key' }
+      let(:file) { File.expand_path('../../../fixtures/good.zip', File.dirname(__FILE__)) }
+      let(:workspace) { Dir.mktmpdir }
+
+      let(:blobstore_config) do
+        {
+          external_host: cc_addr,
+          tls_port: cc_port,
+          droplets: {
+            droplet_directory_key: 'cc-droplets',
+            fog_connection: {
+              provider: 'Local',
+              local_root: Dir.mktmpdir('droplets', workspace)
+            }
+          },
+          directories: {
+            tmpdir: Dir.mktmpdir('tmpdir', workspace)
+          },
+          index: 99,
+          name: 'api_z1'
+        }
+      end
+
+      subject(:job) do
+        BuildpackCacheCleanup.new
+      end
+
+      before do
+        TestConfig.override(blobstore_config)
+      end
+
+      let(:blobstore) do
+        CloudController::DependencyLocator.instance.buildpack_cache_blobstore
+      end
+
+      let(:droplet_blobstore) do
+        CloudController::DependencyLocator.instance.droplet_blobstore
+      end
+
+      after do
+        FileUtils.rm_rf(workspace)
+      end
+
+      it 'deletes everything from the buildpack_cache directory' do
+        Fog.unmock!
+        blobstore.cp_to_blobstore(file, orphan_key)
+        blobstore.cp_to_blobstore(file, buildpack_cache_key)
+
+        expect(blobstore.exists?(orphan_key)).to be_truthy
+        expect(blobstore.exists?(buildpack_cache_key)).to be_truthy
+
+        job.perform
+
+        expect(blobstore.exists?(orphan_key)).to be_falsey
+        expect(blobstore.exists?(buildpack_cache_key)).to be_falsey
+      end
+
+      it 'does not delete any droplets' do
+        Fog.unmock!
+        blobstore.cp_to_blobstore(file, orphan_key)
+        droplet_blobstore.cp_to_blobstore(file, droplet_key)
+
+        expect(blobstore.exists?(orphan_key)).to be_truthy
+        expect(droplet_blobstore.exists?(droplet_key)).to be_truthy
+
+        job.perform
+
+        expect(blobstore.exists?(orphan_key)).to be_falsey
+        expect(droplet_blobstore.exists?(droplet_key)).to be_truthy
+      end
+
+      it { is_expected.to be_a_valid_job }
+    end
+  end
+end

spec/unit/models/runtime/pollable_job_model_spec.rb

@@ -56,6 +56,11 @@ module VCAP::CloudController
         expect(job.resource_exists?).to be(false)
       end
 
+      it 'returns false if the resource type is empty' do
+        job = PollableJobModel.make(resource_type: '', resource_guid: '')
+        expect(job.resource_exists?).to be(false)
+      end
+
       context 'when the resource is a special case' do
         it 'returns true if the resource exists' do
           organization_quota = QuotaDefinition.make