retry_with.rb

# Runs a block multiple times, each time with a different alternative
# Intended for connection failover
# Inspired by http://github.com/carlo/retryable

module RetryWith

  def retry_with(alternatives, options={}, &block)
    opts = {:tries => alternatives.size, :on => Exception}.merge(options)

    return if opts[:tries] == 0

    retry_exceptions, tries = [opts[:on]].flatten, 0

    begin
      return yield(alternatives[tries])
    rescue *retry_exceptions
      retry if (tries += 1) < opts[:tries]
      raise $!
    end
  end

end