Event Grid¶
Subscribe to Event Grid events and route them into isolated worker handlers.
flowchart TD
A[Trigger] --> B[Function]
B --> C[Binding or SDK]
C --> D[Azure service]Topic/Command Groups¶
Event Grid trigger¶
[Function("BlobCreatedEvent")]
public void BlobCreatedEvent([EventGridTrigger] BinaryData eventData)
{
}
Subscription setup¶
az eventgrid event-subscription create --name "sub-func-events" --source-resource-id "<source-resource-id>" --endpoint-type azurefunction --endpoint "/subscriptions/<subscription-id>/resourceGroups/$RG/providers/Microsoft.Web/sites/$APP_NAME/functions/BlobCreatedEvent"
| CLI element | Explanation |
|---|---|
| Command(s) | az eventgrid event-subscription create |
| Key flags | --name, --source-resource-id, --endpoint-type, --endpoint |
| Variables | $RG, $APP_NAME |
| Expected result | Azure CLI returns provisioning details; confirm the resource name and successful provisioning state before continuing. |
Event Grid output (publish to a custom topic)¶
Use the EventGridOutput attribute to publish events to a custom topic. The attribute reads the topic endpoint and access key from app settings; never hard-code the topic URI. For a single event, return a JSON-serializable type:
public class PublishFunction
{
[Function(nameof(PublishFunction))]
[EventGridOutput(TopicEndpointUri = "MyEventGridTopicUriSetting", TopicKeySetting = "MyEventGridTopicKeySetting")]
public MyEvent Run([TimerTrigger("0 */5 * * * *")] TimerInfo timer)
{
return new MyEvent
{
Id = "unique-id",
Subject = "orders/created",
EventType = "Contoso.Order.Created",
EventTime = DateTime.UtcNow,
Data = new Dictionary<string, object> { { "orderId", 12345 } },
};
}
}
To publish multiple events, return an array of the event type. For CloudEvents 1.0 output or advanced scenarios (batching, custom schema), register an EventGridPublisherClient from Azure.Messaging.EventGrid via dependency injection instead of the output binding.
az functionapp config appsettings set \
--name $APP_NAME \
--resource-group $RG \
--settings "MyEventGridTopicUriSetting=$TOPIC_ENDPOINT" "MyEventGridTopicKeySetting=$TOPIC_KEY"
| CLI element | Explanation |
|---|---|
| Command(s) | az functionapp config appsettings set |
| Key flags | --name, --resource-group, --settings |
| Variables | $APP_NAME, $RG, $TOPIC_ENDPOINT, $TOPIC_KEY |
| Expected result | Azure CLI returns the updated app settings as JSON; confirm both settings are present before continuing. |