https://www.openmaru.io/kafka-03-kafka-%ec%9d%98-%ec%9e%a5%ec%a0%90%ea%b3%bc-%ec%9d%b4%ec%a0%84-%eb%a9%94%ec%84%b8%ec%a7%95-%ec%8b%9c%ec%8a%a4%ed%85%9c%ea%b3%bc%ec%9d%98-%ec%b0%a8%ec%9d%b4%ec%a0%90/