Allow SKIP=remote option to be specified during backup

Even if you have set backup_upload_connection,
you can skip the process of uploading the backup file
to the cloud storage by giving the SKIP=remote option.

Changelog: added

doc/raketasks/backup_restore.md

@@ -724,6 +724,23 @@ sudo gitlab-backup create DIRECTORY=weekly
 
 Users of GitLab 12.1 and earlier should use the command `gitlab-rake gitlab:backup:create` instead.
 
+#### Skip uploading backups to remote storage
+
+If you have configured GitLab to [upload backups in a remote storage](#uploading-backups-to-a-remote-cloud-storage),
+you can use the `SKIP=remote` option to skip uploading your backups to the remote storage.
+
+For Omnibus GitLab packages:
+
+```shell
+sudo gitlab-backup create SKIP=remote
+```
+
+For installations from source:
+
+```shell
+sudo -u git -H bundle exec rake gitlab:backup:create SKIP=remote RAILS_ENV=production
+```
+
 #### Uploading to locally mounted shares
 
 You may also send backups to a mounted share (for example, `NFS`,`CIFS`, or

lib/backup/manager.rb

@@ -229,7 +229,7 @@ module Backup
 
     def upload
       connection_settings = Gitlab.config.backup.upload.connection
-      if connection_settings.blank?
+      if connection_settings.blank? || skipped?('remote')
         puts_time "Uploading backup archive to remote storage #{remote_directory} ... ".color(:blue) + "[SKIPPED]".color(:cyan)
         return
       end

spec/lib/backup/manager_spec.rb

@@ -442,6 +442,23 @@ RSpec.describe Backup::Manager do
         connection.directories.create(key: Gitlab.config.backup.upload.remote_directory) # rubocop:disable Rails/SaveBang
       end
 
+      context 'skipped upload' do
+        let(:backup_information) do
+          {
+            backup_created_at: Time.zone.parse('2019-01-01'),
+            gitlab_version: '12.3',
+            skipped: ['remote']
+          }
+        end
+
+        it 'informs the user' do
+          stub_env('SKIP', 'remote')
+          subject.create # rubocop:disable Rails/SaveBang
+
+          expect(Gitlab::BackupLogger).to have_received(:info).with(message: 'Uploading backup archive to remote storage directory ... [SKIPPED]')
+        end
+      end
+
       context 'target path' do
         it 'uses the tar filename by default' do
           expect_any_instance_of(Fog::Collection).to receive(:create)