What are Azure Event Hubs?

Azure Event Hubs is a highly scalable data streaming platform and event ingestion service. It can capture, transform, and store millions of events per second. It's designed for big data streaming scenarios.

Core Concepts

Event Hubs works with event producers and event consumers. Producers send events to an Event Hub, and consumers read events from it. Here are the fundamental components:

Event Producers

An event producer is any application or device that sends data records (events) to an Event Hub. Producers can send events individually or in batches.

Event Consumers

An event consumer is any application that reads data records from an Event Hub. Consumers typically work in consumer groups to process events in parallel and independently.

Event Hub

An Event Hub is the central entity where data streams are ingested. It acts as a buffer for events and ensures their durability.

Consumer Groups

A consumer group is a view of an Event Hub that allows multiple applications to read from the same Event Hub independently. Each consumer group maintains its own position in the stream, enabling different applications or services to process the same events without interfering with each other.

Partitions

Event Hubs organizes event streams into partitions. A partition is an ordered sequence of events. The number of partitions is a crucial design choice for Event Hubs and determines the level of parallelism for consumers. Events are routed to specific partitions based on a partitioning key or round-robin if no key is provided.

Partition Key

A partition key is used by producers to determine which partition an event should be sent to. Events with the same partition key are guaranteed to be sent to the same partition. This is useful for maintaining order for specific entities (e.g., all events from a single device go to the same partition).

How it Works

When data arrives at an Event Hub, it's immediately persisted and made available for consumption. Event Hubs supports several protocols for sending and receiving data, including:

• AMQP (Advanced Message Queuing Protocol)
• Kafka protocol
• HTTPS

Consumers can connect to Event Hubs using various SDKs provided by Azure or compatible libraries like the Kafka client.

Benefits of Using Event Hubs

• High Throughput: Designed to handle millions of events per second.
• Scalability: Easily scales to accommodate growing data volumes.
• Low Latency: Real-time processing of streaming data.
• Durability: Events are persisted for a configurable retention period.
• Integration: Seamless integration with other Azure services like Azure Functions, Azure Stream Analytics, and Azure Databricks.

Event Hubs is a powerful tool for building real-time data processing pipelines and enabling event-driven architectures within Azure.