What are Azure Event Hubs?

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Introduction

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. Applications and services generate events, which are then sent to an Event Hub. Data processing platforms can then consume the events in real-time or store them for batch processing.

Event Hubs is a foundational component for modern application architectures that deal with large volumes of telemetry, logs, clickstreams, or any other event-driven data. It acts as a "front door" for event data, enabling decoupled architectures where event producers and consumers can operate independently.

Key Concepts

Producers

Applications or devices that send event data to an Event Hub. Producers don't need to know about the consumers; they just send data to the hub.

Consumers

Applications that read and process event data from an Event Hub. Consumers can be part of a stream processing platform or custom applications.

Event Hub

The central unit that ingests event streams. An Event Hub is organized into partitions, which allow for parallel processing.

Partitions

Ordered sequences of events within an Event Hub. Data is distributed across partitions to enable high throughput and parallel processing. Events with the same partitioning key are sent to the same partition.

Consumer Groups

A unique view of the event stream. Each consumer group allows multiple applications to read the Event Hub data independently without interfering with each other.

Common Use Cases

  • Real-time analytics: Processing and analyzing streaming data for immediate insights (e.g., fraud detection, IoT device monitoring).
  • Log aggregation: Collecting logs from distributed applications and services for centralized analysis and troubleshooting.
  • Telematics and IoT: Ingesting data from millions of connected devices (e.g., smart meters, vehicles, industrial sensors).
  • Clickstream analysis: Capturing user interaction data from websites and applications for personalization and analytics.
  • Event sourcing: Using Event Hubs as a durable event log for building event-sourced systems.

Benefits of Event Hubs

  • Scalability: Handles millions of events per second, scaling automatically or with configuration adjustments.
  • Low Latency: Designed for real-time data ingestion with minimal delay.
  • Durability: Events are persisted for a configurable retention period, allowing for replay and recovery.
  • Decoupling: Separates event producers from consumers, allowing independent development and scaling.
  • Integration: Seamlessly integrates with other Azure services like Azure Functions, Azure Stream Analytics, and Azure Databricks.
  • Security: Offers robust security features including SAS tokens, Azure AD authentication, and private endpoints.

Getting Started

To start using Azure Event Hubs, you'll typically follow these steps:

  1. Create an Azure Event Hubs namespace in the Azure portal.
  2. Create an Event Hub within the namespace.
  3. Configure access policies and connection strings.
  4. Develop your producer applications to send data to the Event Hub.
  5. Develop your consumer applications (or use Azure services) to read data from the Event Hub.

You can find detailed guides and code examples in the Create an Event Hub tutorial and explore the concept of Throughput Units for performance tuning.