Catch more errors in oai-pmh config when database does not exist yet

Author: eilmiv

config/initializers/oai_provider.rb

@@ -24,6 +24,6 @@ class TrainingProvider < OAI::Provider::Base
 
 Rails.application.config.after_initialize do
   TrainingProvider.source_model OAI::Provider::ActiveRecordWrapper.new(Material.where(visible: true))
-rescue ActiveRecord::NoDatabaseError, ActiveRecord::StatementInvalid
+rescue ActiveRecord::NoDatabaseError, ActiveRecord::StatementInvalid, ActiveRecord::ConnectionNotEstablished
   Rails.logger.debug 'There is no database yet, so the OAI-PMH endpoint is not configured.'
 end