Dear Flink Community! I would like to open the discussion of contributing Pulsar Flink connector [0] back to Flink.
## A brief introduction to Apache Pulsar Apache Pulsar[1] is a multi-tenant, high-performance distributed pub-sub messaging system. Pulsar includes multiple features such as native support for multiple clusters in a Pulsar instance, with seamless geo-replication of messages across clusters, very low publish and end-to-end latency, seamless scalability to over a million topics, and guaranteed message delivery with persistent message storage provided by Apache BookKeeper. Nowadays, Pulsar has been adopted by more and more companies[2]. ## The status of Pulsar Flink connector The Pulsar Flink connector we are planning to contribute is built upon Flink 1.9.0 and Pulsar 2.4.0. The main features are: - Pulsar as a streaming source with exactly-once guarantee. - Sink streaming results to Pulsar with at-least-once semantics. (We would update this to exactly-once as well when Pulsar gets all transaction features ready in its 2.5.0 version) - Build upon Flink new Table API Type system (FLIP-37[3]), and can automatically (de)serialize messages with the help of Pulsar schema. - Integrate with Flink new Catalog API (FLIP-30[4]), which enables the use of Pulsar topics as tables in Table API as well as SQL client. ## Reference [0] https://github.com/streamnative/pulsar-flink [1] https://pulsar.apache.org/ [2] https://pulsar.apache.org/en/powered-by/ [3] https://cwiki.apache.org/confluence/display/FLINK/FLIP-37%3A+Rework+of+the+Table+API+Type+System [4] https://cwiki.apache.org/confluence/display/FLINK/FLIP-30%3A+Unified+Catalog+APIs Best, Yijie Shen
