Metadata change alerts

Overview

OpenTV Video Platform can be configured to send notifications to client applications to let them know that changes have been made to previously ingested metadata. (These are purely notifications – they do not deliver the actual changes to the clients.)

This allows a client application to "decide" whether the data describing these changes are required immediately, and also to decide exactly what new metadata is required. This allows EPG dataflows to be controlled in terms of both scheduling and specificity, which ensures that the client does not need to request the full metadata set when only a minor change may have taken place.

Changes for which notifications are available for include: 

• Changes to either VOD or BTV (live) metadata
• Rescheduling of events
• Deletion of content

The client application can respond to the notification appropriately, depending on the change communicated in the notification. For example:

• If the change is to a content's metadata, it can request the updated metadata for the content and update what is presented to the user.
• If the change is a schedule change, it can request the updated start and end times for the affected programmes/channels and update the EPG accordingly.
  

Enabling metadata change alerts

There are three things you need to do to enable this feature:

1. Register the device with the Open Device Messaging (ODM) so that it can receive notifications.
   Note that this call is made from the client application itself.
2. Subscribe devices to the metadata alert topic in Device Messaging Manager (DMM).
   Note that this is not a client call – it is typically made from an operator's CRM system.
3. Have the client respond to each type of notification appropriately. (For example, request EPG changes for a particular time period if the notification is for an EPG change.)