Update Import/Export to use object storage (based on aa feature flag)

app/controllers/projects_controller.rb

@@ -2,6 +2,7 @@ class ProjectsController < Projects::ApplicationController
   include IssuableCollections
   include ExtractsPath
   include PreviewMarkdown
+  include SendFileUpload
   before_action :whitelist_query_limiting, only: [:create]
   before_action :authenticate_user!, except: [:index, :show, :activity, :refs]
@@ -188,9 +189,9 @@ class ProjectsController < Projects::ApplicationController
   end
   def download_export
-    export_project_path = @project.export_project_path
-
-    if export_project_path
+    if export_project_object_storage?
+      send_upload(@project.import_export_upload.export_file)
+    elsif export_project_path
       send_file export_project_path, disposition: 'attachment'
     else
       redirect_to(
@@ -265,8 +266,6 @@ class ProjectsController < Projects::ApplicationController
     render json: options.to_json
   end
-  private
-
   # Render project landing depending of which features are available
   # So if page is not availble in the list it renders the next page
   #
@@ -424,4 +423,12 @@ class ProjectsController < Projects::ApplicationController
   def whitelist_query_limiting
     Gitlab::QueryLimiting.whitelist('https://gitlab.com/gitlab-org/gitlab-ce/issues/42440')
   end
+
+  def export_project_path
+    @export_project_path ||= @project.export_project_path
+  end
+
+  def export_project_object_storage?
+    @project.export_project_object_exists?
+  end
 end

app/models/import_export_upload.rb

+class ImportExportUpload < ActiveRecord::Base
+  include WithUploads
+  include ObjectStorage::BackgroundMove
+
+  belongs_to :project
+
+  mount_uploader :import_file, ImportExportUploader
+  mount_uploader :export_file, ImportExportUploader
+
+  def retrieve_upload(_identifier, paths)
+    Upload.find_by(model: self, path: paths)
+  end
+end

app/models/project.rb

@@ -171,6 +171,7 @@ class Project < ActiveRecord::Base
   has_one :fork_network, through: :fork_network_member
   has_one :import_state, autosave: true, class_name: 'ProjectImportState', inverse_of: :project
+  has_one :import_export_upload, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   # Merge Requests for target project should be removed with it
   has_many :merge_requests, foreign_key: 'target_project_id'
@@ -1712,7 +1713,7 @@ class Project < ActiveRecord::Base
       :started
     elsif after_export_in_progress?
       :after_export_action
-    elsif export_project_path
+    elsif export_project_path || export_project_object_exists?
       :finished
     else
       :none
@@ -1727,16 +1728,21 @@ class Project < ActiveRecord::Base
     import_export_shared.after_export_in_progress?
   end
-  def remove_exports
-    return nil unless export_path.present?
-
-    FileUtils.rm_rf(export_path)
+  def remove_exports(path = export_path)
+    if path.present?
+      FileUtils.rm_rf(path)
+    elsif export_project_object_exists?
+      import_export_upload.remove_export_file!
+      import_export_upload.save
+    end
   end
   def remove_exported_project_file
-    return unless export_project_path.present?
-    FileUtils.rm_f(export_project_path)
+    remove_exports(export_project_path)
+  end
+  def export_project_object_exists?
+    Gitlab::ImportExport.object_storage? && import_export_upload&.export_file&.file
   end
   def full_path_slug

app/services/import_export_clean_up_service.rb

@@ -10,7 +10,9 @@ class ImportExportCleanUpService
   def execute
     Gitlab::Metrics.measure(:import_export_clean_up) do
-      next unless File.directory?(path)
+      clean_up_export_object_files
+
+      break unless File.directory?(path)
       clean_up_export_files
     end
@@ -21,4 +23,11 @@ class ImportExportCleanUpService
   def clean_up_export_files
     Gitlab::Popen.popen(%W(find #{path} -not -path #{path} -mmin +#{mmin} -delete))
   end
+
+  def clean_up_export_object_files
+    ImportExportUpload.where('updated_at < ?', mmin.minutes.ago).each do |upload|
+      upload.remove_export_file!
+      upload.save!
+    end
+  end
 end

app/uploaders/import_export_uploader.rb

+class ImportExportUploader < AttachmentUploader
+  EXTENSION_WHITELIST = %w[tar.gz].freeze
+
+  def extension_whitelist
+    EXTENSION_WHITELIST
+  end
+
+  def move_to_store
+    true
+  end
+
+  def move_to_cache
+    false
+  end
+end

app/views/projects/_export.html.haml

@@ -31,7 +31,7 @@
           %li Any encrypted tokens
     %p
       Once the exported file is ready, you will receive a notification email with a download link, or you can download it from this page.
-    - if project.export_project_path
+    - if project.export_status == :finished
       = link_to 'Download export',  download_export_project_path(project),
               rel: 'nofollow', download: '', method: :get, class: "btn btn-default"
       = link_to 'Generate new export',  generate_new_export_project_path(project),

changelogs/unreleased/46246-gitlab-project-export-should-use-object-storage.yml

+---
+title: Add Object Storage to project export
+merge_request: 20105
+author:
+type: added

db/migrate/20180625113853_create_import_export_uploads.rb

+class CreateImportExportUploads < ActiveRecord::Migration
+  DOWNTIME = false
+
+  def change
+    create_table :import_export_uploads do |t|
+      t.datetime_with_timezone :updated_at, null: false
+
+      t.references :project, index: true, foreign_key: { on_delete: :cascade }, unique: true
+
+      t.text :import_file
+      t.text :export_file
+    end
+
+    add_index :import_export_uploads, :updated_at
+  end
+end

db/schema.rb

@@ -949,6 +949,16 @@ ActiveRecord::Schema.define(version: 20180702120647) do
   add_index "identities", ["user_id"], name: "index_identities_on_user_id", using: :btree
+  create_table "import_export_uploads", force: :cascade do |t|
+    t.datetime_with_timezone "updated_at", null: false
+    t.integer "project_id"
+    t.text "import_file"
+    t.text "export_file"
+  end
+
+  add_index "import_export_uploads", ["project_id"], name: "index_import_export_uploads_on_project_id", using: :btree
+  add_index "import_export_uploads", ["updated_at"], name: "index_import_export_uploads_on_updated_at", using: :btree
+
   create_table "internal_ids", id: :bigserial, force: :cascade do |t|
     t.integer "project_id"
     t.integer "usage", null: false

doc/administration/raketasks/project_import_export.md

@@ -30,5 +30,12 @@ sudo gitlab-rake gitlab:import_export:data
 bundle exec rake gitlab:import_export:data RAILS_ENV=production
 ```
+In order to enable Object Storage on the Export, you can use the [feature flag][feature-flags]:
+
+```
+import_export_object_storage
+``` 
+
 [ce-3050]: https://gitlab.com/gitlab-org/gitlab-ce/issues/3050
+[feature-flags]: https://docs.gitlab.com/ee/api/features.html
 [tmp]: ../../development/shared_files.md

lib/api/project_export.rb

@@ -23,9 +23,13 @@ module API
       get ':id/export/download' do
         path = user_project.export_project_path
-        render_api_error!('404 Not found or has expired', 404) unless path
-
-        present_disk_file!(path, File.basename(path), 'application/gzip')
+        if path
+          present_disk_file!(path, File.basename(path), 'application/gzip')
+        elsif user_project.export_project_object_exists?
+          present_carrierwave_file!(user_project.import_export_upload.export_file)
+        else
+          render_api_error!('404 Not found or has expired', 404)
+        end
       end
       desc 'Start export' do

lib/gitlab/import_export.rb

@@ -40,6 +40,10 @@ module Gitlab
       "#{basename[0..FILENAME_LIMIT]}_export.tar.gz"
     end
+    def object_storage?
+      Feature.enabled?(:import_export_object_storage)
+    end
+
     def version
       VERSION
     end

lib/gitlab/import_export/after_export_strategies/base_after_export_strategy.rb

@@ -24,9 +24,10 @@ module Gitlab
         end
         def execute(current_user, project)
-          return unless project&.export_project_path
-
           @project = project
+
+          return unless @project.export_status == :finished
+
           @current_user = current_user
           if invalid?
@@ -51,9 +52,12 @@ module Gitlab
         end
         def self.lock_file_path(project)
-          return unless project&.export_path
-          File.join(project.export_path, AFTER_EXPORT_LOCK_FILE_NAME)
+          return unless project.export_path || object_storage?
+          lock_path = project.import_export_shared.archive_path
+
+          FileUtils.mkdir_p(lock_path)
+          File.join(lock_path, AFTER_EXPORT_LOCK_FILE_NAME)
         end
         protected
@@ -77,6 +81,10 @@ module Gitlab
         def log_validation_errors
           errors.full_messages.each { |msg| project.import_export_shared.add_error_message(msg) }
         end
+
+        def object_storage?
+          project.export_project_object_exists?
+        end
       end
     end
   end

lib/gitlab/import_export/after_export_strategies/web_upload_strategy.rb

@@ -38,14 +38,20 @@ module Gitlab
         private
         def send_file
-          export_file = File.open(project.export_project_path)
-
-          Gitlab::HTTP.public_send(http_method.downcase, url, send_file_options(export_file)) # rubocop:disable GitlabSecurity/PublicSend
+          Gitlab::HTTP.public_send(http_method.downcase, url, send_file_options) # rubocop:disable GitlabSecurity/PublicSend
         ensure
-          export_file.close if export_file
+          export_file.close if export_file && !object_storage?
+        end
+
+        def export_file
+          if object_storage?
+            project.import_export_upload.export_file.file.open
+          else
+            File.open(project.export_project_path)
+          end
         end
-        def send_file_options(export_file)
+        def send_file_options
           {
             body_stream: export_file,
             headers: headers
@@ -53,7 +59,15 @@ module Gitlab
         end
         def headers
-          { 'Content-Length' => File.size(project.export_project_path).to_s }
+          { 'Content-Length' => export_size.to_s }
+        end
+
+        def export_size
+          if object_storage?
+            project.import_export_upload.export_file.file.size
+          else
+            File.size(project.export_project_path)
+          end
         end
       end
     end

lib/gitlab/import_export/saver.rb

@@ -15,15 +15,22 @@ module Gitlab
       def save
         if compress_and_save
           remove_export_path
+
           Rails.logger.info("Saved project export #{archive_file}")
-          archive_file
+
+          save_on_object_storage if use_object_storage?
         else
-          @shared.error(Gitlab::ImportExport::Error.new("Unable to save #{archive_file} into #{@shared.export_path}"))
+          @shared.error(Gitlab::ImportExport::Error.new(error_message))
           false
         end
       rescue => e
         @shared.error(e)
         false
+      ensure
+        if use_object_storage?
+          remove_archive
+          remove_export_path
+        end
       end
       private
@@ -36,9 +43,29 @@ module Gitlab
         FileUtils.rm_rf(@shared.export_path)
       end
+      def remove_archive
+        FileUtils.rm_rf(@shared.archive_path)
+      end
+
       def archive_file
         @archive_file ||= File.join(@shared.archive_path, Gitlab::ImportExport.export_filename(project: @project))
       end
+
+      def save_on_object_storage
+        upload = ImportExportUpload.find_or_initialize_by(project: @project)
+
+        File.open(archive_file) { |file| upload.export_file = file }
+
+        upload.save!
+      end
+
+      def use_object_storage?
+        Gitlab::ImportExport.object_storage?
+      end
+
+      def error_message
+        "Unable to save #{archive_file} into #{@shared.export_path}. Object storage enabled: #{use_object_storage?}"
+      end
     end
   end
 end

spec/controllers/projects_controller_spec.rb

@@ -790,23 +790,55 @@ describe ProjectsController do
       project.add_master(user)
     end
-    context 'when project export is enabled' do
-      it 'returns 302' do
-        get :download_export, namespace_id: project.namespace, id: project
-        expect(response).to have_gitlab_http_status(302)
+    context 'object storage disabled' do
+      before do
+        stub_feature_flags(import_export_object_storage: false)
+      end
+      context 'when project export is enabled' do
+        it 'returns 302' do
+          get :download_export, namespace_id: project.namespace, id: project
+
+          expect(response).to have_gitlab_http_status(302)
+        end
+      end
+
+      context 'when project export is disabled' do
+        before do
+          stub_application_setting(project_export_enabled?: false)
+        end
+
+        it 'returns 404' do
+          get :download_export, namespace_id: project.namespace, id: project
+
+          expect(response).to have_gitlab_http_status(404)
+        end
       end
     end
-    context 'when project export is disabled' do
+    context 'object storage enabled' do
       before do
-        stub_application_setting(project_export_enabled?: false)
+        stub_feature_flags(import_export_object_storage: true)
       end
-      it 'returns 404' do
-        get :download_export, namespace_id: project.namespace, id: project
-        expect(response).to have_gitlab_http_status(404)
+      context 'when project export is enabled' do
+        it 'returns 302' do
+          get :download_export, namespace_id: project.namespace, id: project
+          expect(response).to have_gitlab_http_status(302)
+        end
+      end
+
+      context 'when project export is disabled' do
+        before do
+          stub_application_setting(project_export_enabled?: false)
+        end
+
+        it 'returns 404' do
+          get :download_export, namespace_id: project.namespace, id: project
+
+          expect(response).to have_gitlab_http_status(404)
+        end
       end
     end
   end

spec/factories/import_export_uploads.rb

+FactoryBot.define do
+  factory :import_export_upload do
+    project { create(:project) }
+  end
+end

spec/factories/projects.rb

@@ -103,6 +103,22 @@ FactoryBot.define do
     end
     trait :with_export do
+      before(:create) do |_project, _evaluator|
+        allow(Feature).to receive(:enabled?).with(:import_export_object_storage) { false }
+        allow(Feature).to receive(:enabled?).with('import_export_object_storage') { false }
+      end
+
+      after(:create) do |project, _evaluator|
+        ProjectExportWorker.new.perform(project.creator.id, project.id)
+      end
+    end
+
+    trait :with_object_export do
+      before(:create) do |_project, _evaluator|
+        allow(Feature).to receive(:enabled?).with(:import_export_object_storage) { true }
+        allow(Feature).to receive(:enabled?).with('import_export_object_storage') { true }
+      end
+
       after(:create) do |project, evaluator|
         ProjectExportWorker.new.perform(project.creator.id, project.id)
       end

spec/features/projects/import_export/export_file_spec.rb

@@ -25,6 +25,7 @@ describe 'Import/Export - project export integration test', :js do
   before do
     allow_any_instance_of(Gitlab::ImportExport).to receive(:storage_path).and_return(export_path)
+    stub_feature_flags(import_export_object_storage: false)
   end
   after do

spec/features/projects/import_export/namespace_export_file_spec.rb

@@ -5,6 +5,7 @@ describe 'Import/Export - Namespace export file cleanup', :js do
   before do
     allow(Gitlab::ImportExport).to receive(:storage_path).and_return(export_path)
+    stub_feature_flags(import_export_object_storage: false)
   end
   after do