Azure Event Hubs Documentation

Prerequisites

Before you begin, ensure you have the following:

• An active Azure subscription. If you don't have one, you can create a free account.
• The Azure CLI installed and configured, or access to the Azure portal.

Step 1: Create an Event Hubs Namespace

An Event Hubs namespace is a logical container for your Event Hubs. All Event Hubs are deployed within a namespace. A namespace provides a unique DNS name, through which you can access your Event Hubs.

Using Azure Portal:

1. Sign in to the Azure portal.
2. Search for "Event Hubs" and select "Event Hubs Namespaces".
3. Click "+ Create".
4. Fill in the required details: Subscription, Resource Group, Region, Namespace name, and Pricing tier.
5. Click "Review + create" and then "Create".

Using Azure CLI:

az eventhubs namespace create --name  --resource-group  --location  --sku Standard
                    

Replace <your-namespace-name>, <your-resource-group>, and <your-region> with your desired values.

Step 2: Create an Event Hub

Within your Event Hubs namespace, you create Event Hubs. An Event Hub is the entity that holds the data streams.

Using Azure Portal:

1. Navigate to your newly created Event Hubs namespace.
2. In the left-hand menu, select "Event Hubs".
3. Click "+ Event Hub".
4. Enter a name for your Event Hub (e.g., myeventhub).
5. Configure settings like Partition count and Message retention if needed, or use the defaults.
6. Click "Create".

Using Azure CLI:

az eventhubs eventhub create --name  --namespace-name  --resource-group 
                    

Replace <your-eventhub-name>, <your-namespace-name>, and <your-resource-group>.

Step 3: Obtain Connection String

To connect your applications to Event Hubs, you'll need a connection string. This string contains authorization credentials.

Using Azure Portal:

1. Navigate to your Event Hubs namespace.
2. In the left-hand menu, select "Shared access policies".
3. Choose an existing policy (e.g., "RootManageSharedAccessKey") or create a new one with appropriate permissions (Listen, Send, or Manage).
4. Copy the "Primary Connection String" or "Secondary Connection String".

Using Azure CLI:

az eventhubs authorization-rule list --namespace-name  --resource-group  --output table
az eventhubs authorization-rule keys list --resource-group  --namespace-name  --name  --output json
                    

You'll typically use the connection string for the root policy or a custom policy you create for sending and listening.

Step 4: Send Events

Now, let's send some events to your Event Hub. You can use various SDKs (e.g., .NET, Java, Python, Node.js) or tools.

Example using Azure SDK for Python:

from azure.eventhub import EventHubProducerClient, EventData

connection_str = "<your-connection-string>"
eventhub_name = "<your-eventhub-name>"

producer = EventHubProducerClient.from_connection_string(connection_str, eventhub_name=eventhub_name)

events_to_send = [
    EventData("Event 1"),
    EventData("Event 2"),
    EventData("Event 3")
]

with producer:
    producer.send_batch(events_to_send)
    print("Events sent successfully!")
                    

Remember to replace <your-connection-string> and <your-eventhub-name>.

Step 5: Receive Events

Applications can consume events from an Event Hub using Consumer Groups. A consumer group allows multiple applications or instances of the same application to read from an Event Hub independently.

Example using Azure SDK for Python:

from azure.eventhub import EventHubConsumerClient

connection_str = "<your-connection-string>"
eventhub_name = "<your-eventhub-name>"
consumer_group = "$Default" # Or your custom consumer group name

consumer = EventHubConsumerClient.from_connection_string(connection_str, consumer_group, eventhub_name=eventhub_name)

def on_event(partition_context, event):
    print(f"Received event: {event.body_as_str()}")
    # Process the event here

with consumer:
    consumer.receive(on_event)
                    

Replace placeholders as before. You might need to create a custom consumer group if you don't want to use the default one.