Producing Events to Azure Event Hubs

This tutorial guides you through the process of sending events to an Azure Event Hub using a common programming language. Event Hubs is a big data streaming platform and event-ingestion service. It can be used for real-time analytics, data processing, and many other scenarios.

Prerequisites

An Azure Subscription.
An Azure Event Hubs namespace and an Event Hub created within it.
Connection string for your Event Hub.
A development environment set up with your chosen language (e.g., Node.js, Python, Java, .NET).

Important Note

For this tutorial, we'll use the Azure SDK for JavaScript. The concepts and patterns are similar across other SDKs.

Step 1: Install the Azure Event Hubs SDK

Open your terminal or command prompt in your project directory and install the necessary package.

npm install @azure/event-hubs

Step 2: Configure Your Connection

You'll need your Event Hubs connection string. It typically looks like this:

Endpoint=sb://your-namespace.servicebus.windows.net/;SharedAccessKeyName=your-key-name;SharedAccessKey=your-secret-key

You can find this in the Azure portal under your Event Hubs namespace's "Shared access policies".

Step 3: Write the Producer Code

Create a new JavaScript file (e.g., producer.js) and add the following code. Replace placeholders with your actual connection string and event hub name.


import { EventHubProducerClient } from "@azure/event-hubs";

// Replace with your actual connection string and hub name
const connectionString = "YOUR_EVENT_HUBS_CONNECTION_STRING";
const eventHubName = "YOUR_EVENT_HUB_NAME";

async function main() {
    const producerClient = new EventHubProducerClient(connectionString, eventHubName);

    console.log("Starting to send events...");

    try {
        const batch = await producerClient.createBatch();
        batch.tryAdd({ body: { message: "Hello from Event Hubs! (Event 1)" } });
        batch.tryAdd({ body: { message: "Another event here. (Event 2)" } });
        batch.tryAdd({ body: { message: "Event Hubs is great! (Event 3)" } });

        await producerClient.sendBatch(batch);
        console.log("Successfully sent a batch of events.");

        // Sending individual events
        await producerClient.sendEvent({ body: "This is a single event." });
        console.log("Successfully sent a single event.");

    } catch (err) {
        console.error("Error sending events:", err);
    } finally {
        await producerClient.close();
        console.log("Producer client closed.");
    }
}

main().catch((err) => {
    console.error("Error in main function:", err);
});

Step 4: Run the Producer

Execute your script from the terminal:

node producer.js

Verifying Events

After running the producer, you can verify that your events have been received by:

Checking the metrics in the Azure portal for your Event Hub.
Setting up an Event Hubs consumer (using another tutorial or a tool like Azure CLI) to read from the hub.

Batching vs. Individual Events

Sending events in batches is generally more efficient than sending them one by one, as it reduces network overhead and improves throughput. The SDK provides mechanisms to create and manage batches.

Next Steps

Now that you can produce events, you might want to learn how to consume them. Check out our tutorial on Consuming Events from Azure Event Hubs.