Creating Graph subscriptions does not honor duplicated behavior

Question

Hi team,

As per document here, creating duplicated Graph subscriptions on the same resource should incur 409 conflict error.

https://learn.microsoft.com/en-us/graph/api/subscription-post-subscriptions?view=graph-rest-1.0&tabs=http#duplicate-subscription-behavior

This behavior has been expected until it's broken recently. I found that by making 2 identical POST requests, 2 different subscriptions can be created successfully without throwing a 409 conflict error.

Can you help check this please?

Thanks.

Answer 1

The behavior you're experiencing with duplicate Graph subscriptions not returning a 409 Conflict error when identical POST requests are made is indeed contrary to the documented expectations. According to the Microsoft Graph documentation, duplicate subscriptions are not allowed, and a request containing the same values for changeType and resource as an existing subscription should result in a 409 Conflict error, along with the message indicating that the subscription ID already exists for the requested combination.

If you are able to create two identical subscriptions without encountering this error, it may be indicative of a change in the service's behavior or a potential issue that needs to be reported to Microsoft support for further investigation. I recommend checking the latest updates or announcements regarding the Microsoft Graph API for any changes that might have affected this behavior.

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References:

• Create subscription
• Create subscription
• Create subscription