class Semian::CircuitBreaker

def log_state_transition(new_state)
  return if @state.nil? || new_state == @state.value
  str = "[#{self.class.name}] State transition from #{@state.value} to #{new_state}."
  str += " success_count=#{@successes.value} error_count=#{@errors.size}"
  str += " success_count_threshold=#{@success_count_threshold} error_count_threshold=#{@error_count_threshold}"
  str += " error_timeout=#{@error_timeout} error_last_at=\"#{@errors.last}\""
  str += " name=\"#{@name}\""
  if new_state == :open && @last_error
    str += " last_error_message=#{@last_error.message.inspect}"
  end
  Semian.logger.info(str)
end