Creating/updating change notification subscriptions does not return the expected ExpirationDateTime value

[jnemeth1]

Describe the bug

When creating or patching a change notification subscription using the .NET MS graph SDK, the ExpirationDateTime is not set to the expected value. I am creating a subscription using the code from https://learn.microsoft.com/en-us/graph/change-notifications-delivery-webhooks?tabs=csharp#subscription-request. I set my ExpirationDateTime value as a DateTimeOffset for 10065 minutes from creation (which should be acceptable for messages according to https://learn.microsoft.com/en-us/graph/api/resources/subscription?view=graph-rest-1.0#subscription-lifetime) and pass it into a new Subscription object. When the request is completed and the subscription object is returned, the ExpirationDateTime does not represent the value I'm setting. It's usually only a day in advance when I would expect it to be around 6 days from creation. The same issue occurs when updating subscriptions using the code from https://learn.microsoft.com/en-us/graph/api/subscription-update?view=graph-rest-1.0&tabs=csharp#request. I have also tried to pass in the ExpirationDateTime as an AdditionalData parameter (suggested in #2269) and the issue persists.

Expected behavior

The resulting subscription object has the expirationDateTime value I provided.

How to reproduce

1. Create C# project and instantiate new GraphServiceClient
2. Create subscription using code at https://learn.microsoft.com/en-us/graph/change-notifications-delivery-webhooks?tabs=csharp#subscription-request and set ExpirationDateTime with something like DateTimeOffset.UtcNow.AddMinutes(10065).
3. Inspect the returned Subscription object and see that the ExpirationDateTime is not what was passed in.

SDK Version

No response

Latest version known to work for scenario above?

No response

Known Workarounds

No response

Debug output

Click to expand log

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### Configuration

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### Other information

_No response_

[mathiastortelb]

Running into the same issue for Microsoft Graph API, but seems to happen only for me when I use rich notifications. Using normal notifications seems to return the correct expirationDateTime. We just switched to rich notifications, so I'm not sure if this is expected behaviour or not. I'm not finding any documentation for this though..

[jnemeth1]

@mathiastortelb I didn't even think of that but we are also using rich notifications, and have since the beginning. I guess this could be intended, but I have also not seen anything in the documentation about it.

[baywet]

Thank you for using the SDK and for reaching out!

This behavior is caused by the backend service and not the SDK. This repository and its issues are dedicated to the SDK, not the backend service. For service-related issues, you can contact the Microsoft Graph support team here: https://developer.microsoft.com/graph/support
Alternatively, you can also use the Microsoft Q&A forum for community support: https://learn.microsoft.com/en-us/answers/tags/161/ms-graph

If you have any other questions or need further assistance, please let us know!

[microsoft-github-policy-service]

This issue has been automatically marked as stale because it has been marked as requiring author feedback but has not had any activity for 4 days. It will be closed if no further activity occurs within 3 days of this comment.