Safeish Retryable Transactions for RoR

transaction_helper.rb

module TransactionHelper
  extend ActiveSupport::Concern

  included do
    def retryable_transaction(isolation = :serializable, &block)
      txn_retries = 0
      begin
        self.transaction(isolation: isolation, &block)
      rescue ::ActiveRecord::StatementInvalid => exc
        if exc.original_exception.is_a?(::PG::TransactionRollback)
          txn_retries += 1
          retry if txn_retries <= Settings.max_txn_retries
        end
        raise
      end
    end   
  end
end