Delivery Properties

Author: spelluru

articles/event-grid/event-schema-event-hubs.md

@@ -122,6 +122,17 @@ The data object has the following properties:
 | `firstEnqueueTime` | string | The first time from the queue. |
 | `lastEnqueueTime` | string | The last time from the queue. |
 
+## Delivery properties
+Event subscriptions allow you to set up HTTP headers that are included in delivered events. This capability allows you to set custom headers that are required by a destination. You can set custom headers on the events that are delivered to Azure Event Hubs.
+
+If you need to publish events to a specific partition within an event hub, set the `ParitionKey` property on your event subscription to specify the partition key that identifies the target event hub partition.
+
+| Header name | Header type |
+| :-- | :-- |
+|`PartitionKey` | Static |
+
+For more information, see [Custom delivery properties](delivery-properties.md). 
+
 ## Tutorials and how-tos
 
 |Title  |Description  |

articles/event-grid/handler-event-hubs.md

@@ -2,7 +2,7 @@
 title: Event hub as an event handler for Azure Event Grid events
 description: Describes how you can use event hubs as event handlers for Azure Event Grid events.
 ms.topic: conceptual
-ms.date: 09/28/2021
+ms.date: 09/30/2021
 ---
 
 # Event hub as an event handler for Azure Event Grid events

articles/event-grid/handler-service-bus.md

@@ -2,7 +2,7 @@
 title: Service Bus queues and topics as event handlers for Azure Event Grid events
 description: Describes how you can use Service Bus queues and topics as event handlers for Azure Event Grid events.
 ms.topic: conceptual
-ms.date: 09/28/2021
+ms.date: 09/30/2021
 ---
 
 # Service Bus queues and topics as event handlers for Azure Event Grid events
@@ -146,5 +146,28 @@ The internal system ID for the message will be maintained across redelivery of t
 }
 ```
 
+## Delivery properties
+Event subscriptions allow you to set up HTTP headers that are included in delivered events. This capability allows you to set custom headers that are required by a destination. You can set custom headers on the events that are delivered to Azure Service Bus queues and topics.
+
+Azure Service Bus supports the use of following message properties when sending single messages. 
+
+| Header name | Header type |
+| :-- | :-- |
+| `MessageId` | Dynamic |  
+| `PartitionKey` | Static or dynamic |
+| `SessionId` | Static or dynamic |
+| `CorrelationId` | Static or dynamic |
+| `Label` | Static or dynamic |
+| `ReplyTo` | Static or dynamic | 
+| `ReplyToSessionId` | Static or dynamic |
+| `To` |Static or dynamic |
+| `ViaPartitionKey` | Static or dynamic |
+
+> [!NOTE]
+> - The default value of `MessageId` is the internal ID of the Event Grid event. You can override it. For example, `data.field`.
+> - You can only set either `SessionId` or `MessageId`. 
+
+For more information, see [Custom delivery properties](delivery-properties.md). 
+
 ## Next steps
 See the [Event handlers](event-handlers.md) article for a list of supported event handlers. 

articles/event-grid/post-to-custom-topic.md

@@ -6,10 +6,14 @@ ms.date: 08/19/2021
 ms.custom: devx-track-azurepowershell
 ---
 
-# Post to Azure Event Grid custom topics using access keys
+# Publish events to Azure Event Grid custom topics using access keys
 
 This article describes how to post an event to a custom topic using an access key. It shows the format of the post and event data. The [Service Level Agreement (SLA)](https://azure.microsoft.com/support/legal/sla/event-grid/v1_0/) only applies to posts that match the expected format.
 
+
+> [!NOTE]
+> Azure AD authentication provides a superior authentication support than that's offered by access key or Shared Access Signature (SAS) token authentication. With Azure AD authentication, the identity is validated against Azure AD identity provider. As a developer, you won't have to handle keys in your code if you use Azure AD authentication. you'll also benefit from all security features built into the Microsoft Identity platform, such as Conditional Access, that can help you improve your application's security stance. For more information, see [Authenticate publishing clients using Azure Active Directory](authenticate-with-active-directory.md).
+
 ## Endpoint
 
 When sending the HTTP POST to a custom topic, use the URI format: `https://<topic-endpoint>?api-version=2018-01-01`.

articles/event-grid/toc.yml

@@ -252,7 +252,7 @@
       href: auth0-how-to.md
   - name: Get access keys for topics or domains
     href: get-access-keys.md
-  - name: Post to custom topics using access keys
+  - name: Publish events custom topics using access keys
     href: post-to-custom-topic.md
   - name: Receive events at HTTP endpoint
     href: receive-events.md