In this talk, I will introduce different ways to handle errors and message retries in your event streaming applications. Apache Pulsar provides several built-in mechanisms to handle processing failures, including negative acknowledgments, retry topics, dead-letter queues, etc. This proliferation of options can often lead to confusion as to which mechanism is best suited for handling errors in your application.

This hands-on talk presents a collection of error-handling patterns that maintain in-order processing of messages in the event of failure, covering different approaches as they gradually increase in complexity. Working code examples of the patterns will demonstrate these concepts throughout the talk.

At the end of this talk, you will be better equipped to properly handle errors within your Pulsar application by leveraging the patterns introduced. Concrete implementations of these patterns will also be made available after the talk.