When it comes to Apache Kafka, on the consumer side I know it’s a pull model. What about Azure EventHubs? Are they pull or push?
From what I’ve gathered so far unlike kafka event hubs "push" events to the listeners. Can someone confirm? Any additional details or references would be helpful.
A simple google search landed me on the this page to back up my claim
Is there a simple way to test this theory out?
2
Answers
Yes, Azure Event Hub push events to event consumers, there is no need to ‘poll’ for consuming the events. The event processor defines
event handlerswhich are invoked as new events are ingested into the event stream.The event consumer can do something called as
checkpointthat marks the event upto which the events have been consumed.See the doc for more details.
The short answer to this is that the model for consuming events depends on the type of client that your application has chosen to use. The official Azure SDK packages offer consumer types that are push-based and those that are pull-based.
You don’t mention the specific language that you’re using but, since you’re comparing to Kafka, I’ll assume that you’re interested in Java. The
azure-messaging-eventhubsfamily of packages are the current generation of the Azure SDK and has the following clients for reading events:EventProcessorClient: This is a push-based client intended to serve as the primary consumer of events in production scenarios for the majority of workloads. It is responsible for reading and processing events for all partitions of an Event Hub and collaborates with other EventProcessorClient instances using the same Event Hub and consumer group to balance work between them. A high degree of fault tolerance is built-in, allowing the processor to be resilient in the face of errors.EventHubConsumerAsyncClient: This is a push-based client focused on reading events from a single partition using a Flux-based subscription via the Reactor library. This client requires applications to own responsibility for resilience and processing state persistence.EventHubConsumerClient: This is a pull-based client focused on reading events from a single partition using an iterator pattern. This client requires applications to own responsibility for resilience and processing state persistence.More information around the package, its types, and basic usage in the Azure Event Hubs client library for Java overview. More detailed samples can be found in the samples overview, including those for Consuming events and Using the EventProcessorClient.