Get the type of schema supported by an Azure Event Grid topic

This article describes how to get the type of schema (Event Grid event schema, cloud event schema, or custom input schema) supported by an Azure Event Grid topic.

Get the topic endpoint and the access key

  1. Sign in to the Azure portal.

  2. In the search bar, type in Event Grid topics, and select it from the list.

  3. Select the topic.

  4. On the Event Grid Topic page, select the Copy to clipboard button next to the topic's endpoint. Paste or save it somewhere.

    Screenshot that shows the Event Grid topic page.

  5. On the left menu, select Access keys under Settings, and select the Copy to clipboard button next to the key value. Paste or save it.

    Screenshot that shows the access key of a topic.

    You'll use the topic's endpoint and access key in the next section to get the schema type supported by the topic.

Get the schema type

Here's a sample Curl command that sends an HTTP OPTIONS message to the topic. The response would contain the header property aeg-input-event-schema that gives you the schema type supported by the topic.

curl -X OPTIONS "<TOPIC ENDPOINT>" -H "aeg-sas-key: <ACCESS KEY>"

Here's the sample header output from the command:

Content-Length: 0
Server: Microsoft-HTTPAPI/2.0
Strict-Transport-Security: max-age=31536000; includeSubDomains
api-supported-versions: 2018-01-01
x-ms-request-id: 2dd9ca30-c2d9-4c08-b9e1-d29c5ebd9802
aeg-input-event-schema: EventGridEvent
Date: Wed, 13 Jul 2022 20:04:06 GMT

The value of the aeg-input-event-schema header property gives you the type of the schema supported by the topic. In this example, it's the Event Grid event schema. The value for this property is set to one of these values: EventGridEvent, CustomInputEvent, CloudEventV10.

Next steps

For information about schemas, see the following articles: