Can't filter Schema Extension on Messages

Question

Hi Everyone,

I'm having an issue filtering Custom Data (schema) on Messages.

I have added a new Schema Extension with the following info:

id: extmxycdgd8_testing
Properties: "name": "testingId",
"type": "String"

I successfully insert the data in the schema on one of the messages with the value "yes"
Message ID for example is "message1"

When I run the following query:
https://graph.microsoft.com/v1.0/me/messages?$filter=extmxycdgd8_testing/testingId eq 'yes'

I'm expecting Message1 to be return but instead I get the following error:

"code": "RequestBroker--ParseUri",
"message": "Could not find a property named 'e2_51c6f317b29f4d7eaa423d6f4f8bebc1_extmxycdgd8_testing' on type 'Microsoft.OutlookServices.Message'.",

I'm not sure why this query adds "e2_51c6f317b29f4d7eaa423d6f4f8bebc1_" to the string (using the Microsoft Graph Explorer for this test) but I'm suppose to get
ID "message1" returned.

Again, I'm not sure what I am doing wrong here.

Please help.

Mike J.

Answer 1

As per https://learn.microsoft.com/en-us/graph/known-issues#extensions

Filtering on schema extension properties not supported on all entity types Filtering on schema extension properties (using the $filter expression) is not supported for Outlook entity types - contact, event, message, or post.

Using extended properties https://learn.microsoft.com/en-us/graph/api/resources/extended-properties-overview?view=graph-rest-1.0 is probably a better way to go until they support schema extensions in filters