If you’re using Azure Event Hubs to stream data into your big data applications, you’ll want to make sure that your messages are getting through correctly. In this article, we’ll show you how to test your Event Hubs setup with some simple automation.
First, let’s create a test event hub. We’ll call it “testhub.” You can use the Azure Portal to create an Event Hubs namespace and then create the testhub event hub within that namespace.
Once the testhub event hub has been created, we need to create a test message. We’ll use the following JSON for our test message:
{
“name”: “Test User”,
“email”: “test@example.com”,
“age”: 42
}
Next, we need to send the message to the testhub event hub. We can do this using the Azure CLI with the following command:
az eventhubs eventhub publish –resource-group myResourceGroup –namespace-name myNamespace –eventhub-name testhub –message “{\”name\”:\”Test User\”,\”email\”:\”test@example.com\”,\”age\”:42}”
You should see the message appear in the Azure Portal under the “Messages” tab for the testhub event hub.
Now that we have a message in our Event Hub, we need to write some code to read the message and verify that it is correct. We’ll do this in a Node.js console application.
First, we need to install the Azure Event Hubs Node.js SDK:
npm install @azure/event-hubs
Next, we’ll create a file called “read.js” and add the following code to it:
const { EventHubConsumerClient } = require(“@azure/event-hubs”);
// Connect to the event hub
const consumerClient = new EventHubConsumerClient(“
async function main() {
// Get the first message
const messages = await consumerClient.receiveMessages(1);
// Process the message
if (messages.length === 1) {
const message = messages[0];
console.log(`Message: ${message.body}`);
// Verify the message
const data = JSON.parse(message.body);
if (data.name === “Test User” && data.email === “test@example.com” && data.age === 42) {
console.log(“Message is correct!”);
} else {
console.log(“Message is incorrect!”);
}
} else {
console.log(“No messages received!”);
}
}
main
Other related questions:
How do I check messages on event hub?
There is no direct way to check messages on Event Hub. However, you can use the Event Hub REST API to retrieve messages.
How do I monitor event hubs?
There is no built-in monitoring capability for Event Hubs. However, you can use a third-party tool like Datadog or New Relic to monitor your Event Hubs.
Can you manage event hub programmatically?
Yes, you can manage Event Hubs programmatically using the Azure Event Hubs Management SDK.
How do I send a message to event hub?
There are a few ways to send messages to Event Hubs:
You can use the Event Hubs REST API to send messages.
You can use one of the Event Hubs SDKs.
You can use the Azure CLI.
Bibliography
- The Azure Event Hub Performance Testing in just 10 Minutes.
- Event Hub Tasks – Automated Task – serverless360
- Frequently asked questions – Azure Event Hubs
- Send or receive events from Azure Event Hubs using .NET …
- Azure Event Hub Integration test – Stack Overflow
- Azure Event Hub – monitoring and automation
- Load Test for Event Sourcing – Tech Blog