Getting Started with Azure Event Hubs

Welcome to Azure Event Hubs! This guide will walk you through the essential steps to begin using Event Hubs, a highly scalable data streaming platform that can ingest and process millions of events per second.

What is Azure Event Hubs?

Azure Event Hubs is a big data streaming platform and event ingestion service. It can be used to process real-time streaming data. Event Hubs can be used to process streaming data, including data from users, applications, and devices. The data can be processed by various applications and services, such as:

Real-time analytics
Live dashboarding
Application monitoring
Batch processing
Machine learning

Key Concepts

Before diving in, understand these core concepts:

Namespace: A logical container for Event Hubs and Consumer Groups.
Event Hub: A data streaming service that can ingest millions of events per second.
Producer: An application or service that sends events to an Event Hub.
Consumer: An application or service that reads events from an Event Hub.
Consumer Group: A named view of an Event Hub that allows multiple applications to consume events independently without interfering with each other.
Partition: An Event Hub is divided into one or more partitions. Each partition acts as an ordered buffer of events.

Prerequisites

An Azure account. If you don't have one, you can sign up for a free trial.
An Azure subscription.

Step 1: Create an Event Hubs Namespace

A namespace is a unique container for your Event Hubs. You can create one using the Azure portal, Azure CLI, or Azure SDKs.

Using the Azure Portal

Sign in to the Azure portal.
In the search bar, type "Event Hubs" and select "Event Hubs" from the results.
Click "Create".
Select your subscription and resource group (or create a new one).
Enter a unique namespace name.
Choose a region.
Select a pricing tier (e.g., Standard).
Click "Review + create", then "Create".

Step 2: Create an Event Hub

Once the namespace is deployed, you can create an Event Hub within it.

Using the Azure Portal

Navigate to your Event Hubs namespace in the Azure portal.
Under "Entities", click "Event Hubs".
Click "+ Event Hub".
Enter a name for your Event Hub (e.g., myeventhub).
Configure the number of partitions and message retention if needed (defaults are usually fine for getting started).
Click "Create".

Step 3: Get Connection Information

To send and receive events, you'll need the connection string for your Event Hubs namespace.

Using the Azure Portal

Navigate to your Event Hubs namespace in the Azure portal.
Under "Settings", click "Shared access policies".
Click "RootManageSharedAccessKey" (or create a new policy with send/listen permissions).
Copy the "Primary Connection String". This string contains the endpoint and keys needed by your applications.

Important: Treat your connection strings as secrets. Do not embed them directly in client-side code. Use environment variables or Azure Key Vault for secure storage.

Step 4: Send Events (Example using .NET)

Here's a basic example of how to send events using the Azure Event Hubs SDK for .NET. You can find SDKs for other languages in the official Azure documentation.

                
using Azure.Messaging.EventHubs;
using Azure.Messaging.EventHubs.Producer;
using System;
using System.Text;
using System.Threading.Tasks;

async Task SendEventsAsync(string connectionString, string eventHubName)
{
    await using var producerClient = new EventHubProducerClient(connectionString, eventHubName);

    using EventDataBatch eventBatch = await producerClient.CreateBatchAsync();

    for (int i = 1; i <= 5; i++)
    {
        var data = $"Event {i}";
        if (!eventBatch.TryAddMessage(new EventData(Encoding.UTF8.GetBytes(data))))
        {
            throw new Exception($"The event {i} is too large for the batch and cannot be sent.");
        }
    }

    try
    {
        await producerClient.SendAsync(eventBatch);
        Console.WriteLine("A batch of 5 events has been sent.");
    }
    catch (Exception ex)
    {
        Console.WriteLine($"Error sending events: {ex.Message}");
    }
}

// Example usage:
// string connectionString = "YOUR_CONNECTION_STRING";
// string eventHubName = "myeventhub";
// await SendEventsAsync(connectionString, eventHubName);
                
            

Step 5: Receive Events (Example using .NET)

Here's a basic example of how to receive events using the Azure Event Hubs SDK for .NET.

                
using Azure.Messaging.EventHubs;
using Azure.Messaging.EventHubs.Consumer;
using System;
using System.Text;
using System.Threading.Tasks;

async Task ReceiveEventsAsync(string connectionString, string eventHubName, string consumerGroup)
{
    await using var consumerClient = new EventHubConsumerClient(consumerGroup, connectionString, eventHubName);

    Console.WriteLine("Listening for events...");

    await foreach (PartitionEvent partitionEvent in consumerClient.ReadEventsAsync())
    {
        Console.WriteLine($"\nReceived event: '{Encoding.UTF8.GetString(partitionEvent.Data.EventBody.ToArray())}'");
        Console.WriteLine($"\nPartition Id: {partitionEvent.Partition.Id}");
        Console.WriteLine($"\nSequence Number: {partitionEvent.Data.SequenceNumber}");
    }
}

// Example usage:
// string connectionString = "YOUR_CONNECTION_STRING";
// string eventHubName = "myeventhub";
// string consumerGroup = EventHubConsumerClient.DefaultConsumerGroupName; // Or create a named consumer group
// await ReceiveEventsAsync(connectionString, eventHubName, consumerGroup);
                
            

Next Steps

Congratulations! You've successfully set up and sent/received your first events with Azure Event Hubs. Here are some resources to continue your learning: