kafka有没有实现幂等生产者的未来
Has kafka implemented the future of idempotent producer
当我在扫描 kafka 的时候 document, I see an article about idempotent producer，这是一个非常酷的未来。但是，我不确定这是否已在 0.9 版本中实现，或者只是对未来版本的提议。有人知道吗？
在第一个文档部分4.6 消息传递语义
These are not the strongest possible semantics for publishers.
Although we cannot be sure of what happened in the case of a network
error, it is possible to allow the producer to generate a sort of
"primary key" that makes retrying the produce request idempotent. This
feature is not trivial for a replicated system because of course it
must work even (or especially) in the case of a server failure. With
this feature it would suffice for the producer to retry until it
receives acknowledgement of a successfully committed message at which
point we would guarantee the message had been published exactly once.
We hope to add this in a future Kafka version.
这看起来很模糊，这个暗示还没有实现吗？
幂等生产者终于在0.11.0.0版本实现了
https://issues.apache.org/jira/browse/KAFKA-4817
另请阅读这篇文章，了解 Kafka 如何提供 "exactly once" 保证：
https://www.confluent.io/blog/exactly-once-semantics-are-possible-heres-how-apache-kafka-does-it/
当我在扫描 kafka 的时候 document, I see an article about idempotent producer，这是一个非常酷的未来。但是，我不确定这是否已在 0.9 版本中实现，或者只是对未来版本的提议。有人知道吗？
在第一个文档部分4.6 消息传递语义
These are not the strongest possible semantics for publishers. Although we cannot be sure of what happened in the case of a network error, it is possible to allow the producer to generate a sort of "primary key" that makes retrying the produce request idempotent. This feature is not trivial for a replicated system because of course it must work even (or especially) in the case of a server failure. With this feature it would suffice for the producer to retry until it receives acknowledgement of a successfully committed message at which point we would guarantee the message had been published exactly once. We hope to add this in a future Kafka version.
这看起来很模糊，这个暗示还没有实现吗？
幂等生产者终于在0.11.0.0版本实现了 https://issues.apache.org/jira/browse/KAFKA-4817
另请阅读这篇文章，了解 Kafka 如何提供 "exactly once" 保证： https://www.confluent.io/blog/exactly-once-semantics-are-possible-heres-how-apache-kafka-does-it/