Introducing the EVENT SUBSCRIPTION HUB

Since its inception, OnTime for Microsoft has relied on the EWS API to subscribe to streaming notifications for changed events. However, the popularity of EWS streaming notifications has gradually declined, and we are encountering an increasing number of issues with this method.

The Graph API does not support the streaming notification method, prompting us to completely rethink how OnTime receives notifications as EWS support for MS 365 is scheduled to be deprecated.

Microsoft Graph API provides a modern notification mechanism that has several advantages over EWS Streaming Subscriptions:

- Doesn't requires a persistent connection for each subscription
- Can handle many subscriptions efficiently with retry policies and batching.
- Supports subscription expiration and renewal, typically up to 60 minutes for high-security scenarios.

Subscription Hub is an HTTP-based callback API that receives change notifications from Microsoft Graph, handles subscriptions life-cycle and prepares needed data for OnTime Server.

While the EWS Streaming subscription method is still supported we encourage our user organisations to start switching to the OnTime Subscription Hub.

ONTIME DESKTOP

• Event Creation Behavior: Creating an event now defaults to showing the event dialog and inviting the user, rather than directly creating the event on their calendar.
• Group Panel Upgrade: Introduced a new group panel with search functionality and support for group aliases.
• "Working Elsewhere" Status: Events marked as “Working elsewhere” no longer block time in the calendar.

ONTIME ADMIN

• SubHub Configuration: Added SubHub configuration support.
• Manual User Injection: Users can now be injected into OnTime individually, without requiring a full directory sync.
• Dashboard Enhancements: Dashboard now shows the status of the Notice Hub.

OUTLOOK CATERING ADD-IN

• Finalized the integration of the Outlook Catering add-in.

ONTIME BACKEND

• Index Optimization: Improved indexes for the Event/List call to enhance performance.
• Permissions Update: Replaced deprecated directory.read.all permission with a suitable alternative.
• Logging Enhancements: Improved the trace logging for Microsoft Graph API calls.
• SQL Blocking Reduction: Updated event handling to use insert-only operations, minimizing SQL blocking. Cleanup routines now:
• • Remove obsolete event copies
  • Delete events from removed users
  • Retain events marked as deleted for 3 weeks before final deletion