Publish Events with Azure Event Grid SDK for Python

This skill covers the azure-eventgrid Python SDK for building event-driven applications on Azure Event Grid's pub/sub routing service. EventGridPublisherClient authenticates via DefaultAzureCredential against either a topic endpoint or, for Event Grid Namespaces (pull delivery), a namespace endpoint plus a namespace_topic argument on send. Two event formats are supported: the recommended, interoperable CloudEvent (with required type and source, plus optional subject, datacontenttype, dataschema, time, and custom extensions), and the Azure-native EventGridEvent (with required subject, event_type, data, and data_version, and an optional event_time). CloudEvent also accepts a dataschema URL and free-form extensions for custom attributes, while EventGridEvent can carry an auto-set topic field. client.send() accepts a single event or a list, so multiple events can be published in one batched call.

Use it when building event-driven Python applications that need to publish events for other services to react to - order/item lifecycle events, custom application events routed by type or subject, or high-throughput event streams via the async client. Choose CloudEvent for new applications since it's the industry-standard, interoperable format; reach for EventGridEvent only when you specifically need Azure Event Grid's native schema.

Configuration is EVENTGRID_TOPIC_ENDPOINT for topic-based publishing or EVENTGRID_NAMESPACE_ENDPOINT for namespaces. A single CloudEvent publish looks like this:

event = CloudEvent(
    type="MyApp.Events.OrderCreated",
    source="/myapp/orders",
    data={"order_id": "12345", "amount": 99.99}
)
client.send(event)

A list comprehension of CloudEvents can be passed to the same send() call to batch multiple events at once. The async client (azure.eventgrid.aio) mirrors this with an async with context manager and await client.send(event), useful for high-throughput publishing. Namespace-topic publishing uses the same async client but targets a namespace endpoint and passes namespace_topic=topic_name on send() instead of relying on the endpoint alone to identify the destination. There's no explicit return value from a successful send - failures raise, and Event Grid applies built-in retry on the delivery side.

Authenticates via Azure Identity's DefaultAzureCredential (sync or async), and is distributed as the azure-eventgrid PyPI package alongside azure-identity.

Python developers building event-driven systems on Azure who need to publish CloudEvents or EventGridEvents to a topic or namespace, and who follow the SDK's guidance to prefer CloudEvents for new work, batch events when publishing multiple at once, include meaningful subjects for downstream filtering, use the async client for high-throughput scenarios, and set event types deliberately since routing and filtering depend on them.