Getting Started with Azure Event Hubs: Sending and Receiving Messages

This guide will walk you through the fundamental steps of sending and receiving messages using Azure Event Hubs, a highly scalable data streaming platform.

1. Setting Up Your Environment

You'll need the Azure CLI or Azure PowerShell, and the appropriate SDK for your programming language.

Using .NET SDK (Example)

Install the necessary NuGet packages:

dotnet add package Azure.Messaging.EventHubs dotnet add package Azure.Messaging.EventHubs.Processor

2. Connecting to Your Event Hub

You'll need your Event Hub's connection string. You can find this in the Azure portal under your Event Hub namespace's "Shared access policies".

3. Sending Messages

Create an EventHubProducerClient and send events. Each event can contain a payload of any data type.


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

// Replace with your actual connection string and event hub name
string connectionString = Environment.GetEnvironmentVariable("EVENTHUB_CONNECTION_STRING");
string eventHubName = "your-event-hub-name";

await using var producerClient = new EventHubProducerClient(connectionString, eventHubName);

using EventDataBatch eventBatch = await producerClient.CreateBatchAsync();

for (int i = 1; i <= 5; i++)
{
    var message = $"Message {i}";
    if (!eventBatch.TryAddMessage(new EventData(Encoding.UTF8.GetBytes(message))))
    {
        // If the batch is full, send it and start a new one
        throw new Exception($"The batch is full. Failed to add message {i}.");
    }
}

// Send the batch of events
await producerClient.SendAsync(eventBatch);
Console.WriteLine($"Sent a batch of {eventBatch.Count} messages.");

4. Receiving Messages

Use the EventHubConsumerClient to process events. You can consume from a specific consumer group.


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

// Replace with your actual connection string and event hub name
string connectionString = Environment.GetEnvironmentVariable("EVENTHUB_CONNECTION_STRING");
string eventHubName = "your-event-hub-name";
string consumerGroup = EventHubConsumerClient.DefaultConsumerGroupName; // Or your custom consumer group

await using var consumerClient = new EventHubConsumerClient(consumerGroup, connectionString, eventHubName);

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

try
{
    await foreach (PartitionEvent @event in consumerClient.ReadEventsAsync())
    {
        Console.WriteLine($"\nReceived event: {Encoding.UTF8.GetString(@event.Data.EventBody.ToArray())}");
        Console.WriteLine($"  Enqueued Time: {@event.Data.EnqueuedTime.ToLocalTime()}");
        Console.WriteLine($"  Partition Id: {@event.Partition.Id}");
    }
}
catch (TaskCanceledException)
{
    // The operation was cancelled, likely due to timeout or explicit cancellation
    Console.WriteLine("Message consumption task was cancelled.");
}
catch (Exception ex)
{
    Console.WriteLine($"An error occurred: {ex.Message}");
}

Next Steps

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