There is no easy way to do it. Cassandra has Change Data Capture functionality, but it's quite low level (and could depend on version of Cassandra), and it's not easy to use it. You can write your own implementation (pointers in link above), or use something like this, but it's very old. And you'll need to handle deduplication yourself, as when you have RF > 1, every node will receive & write the data.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…