EventMessageDetail - downcasting never kicks in

[PrimosK]

I was looking through Microsoft Graph beta endpoint reference but couldn't find answer to my question.

It relates to:
com.microsoft.graph.models.EventMessageDetail
... and classes that extends this class:

CallEndedEventMessageDetail
CallRecordingEventMessageDetail
CallStartedEventMessageDetail
CallTranscriptEventMessageDetail
ChannelAddedEventMessageDetail
ChannelDeletedEventMessageDetail
ChannelDescriptionUpdatedEventMessageDetail
ChannelRenamedEventMessageDetail
ChannelSetAsFavoriteByDefaultEventMessageDetail
ChannelUnsetAsFavoriteByDefaultEventMessageDetail
ChatRenamedEventMessageDetail
ConversationMemberRoleUpdatedEventMessageDetail
MeetingPolicyUpdatedEventMessageDetail
MembersAddedEventMessageDetail
MembersDeletedEventMessageDetail
MembersJoinedEventMessageDetail
MembersLeftEventMessageDetail
TabUpdatedEventMessageDetail
TeamArchivedEventMessageDetail
TeamCreatedEventMessageDetail
TeamDescriptionUpdatedEventMessageDetail
TeamJoiningDisabledEventMessageDetail
TeamJoiningEnabledEventMessageDetail
TeamRenamedEventMessageDetail
TeamUnarchivedEventMessageDetail
TeamsAppInstalledEventMessageDetail
TeamsAppRemovedEventMessageDetail
TeamsAppUpgradedEventMessageDetail

I was expecting for something like this to work when calling com.microsoft.graph.models.ChatMessage#eventDetail:

final EventMessageDetail eventDetail = chatMessage.eventDetail;

if (eventDetail instanceof CallEndedEventMessageDetail) {
    final Duration callDuration = ((CallEndedEventMessageDetail) eventDetail).callDuration;
    // TBD
}
else if (eventDetail instanceof CallRecordingEventMessageDetail) {
    final Duration callRecordingDuration = ((CallRecordingEventMessageDetail) eventDetail).callRecordingDuration;
    // TBD
}
else ...

... but on my surprise is doesn't as instance of EventMessageDetail is always EventMessageDetail - so none of extended classes is ever instantiated.

Are my expectations of how this API should work wrong? Or is there something more to it?

Is there any other way to achieve what I want with the latest beta api?
AB#10151

[baywet]

Hey @PrimosK
Thanks for reaching out.
The property would be downcasted only if an Odata.type annotation is present in the payload.
What values do you get in the oDataType property of the eventdetail object?

[PrimosK]

Hi @baywet,

See this example:

So oDataType value is #microsoft.graph.membersAddedEventMessageDetail, yet the eventDetail is of type EventMessageDetail instead of MembersAddedEventMessageDetail.

Please let me know if any further information is needed.

[baywet]

Hi @PrimosK ,
Thanks for the additional details. As I suspected the deserialization code is not looking at the odata type when deserializing properties on objects (or even for the main object as far as I understand), it only does that for collections of objects at the moment.

msgraph-sdk-java-core/src/main/java/com/microsoft/graph/serializer/CollectionResponseSerializer.java

Line 89 in f8a44b0

Class<?> entityClass = serializer.getDerivedClass(sourceObject, baseEntityClass);

This code should probably be moved into its own deserializer for any IJsonBackedObject. The tricky part will be to ensure it doesn't override any other custom deserializer.
I'm going to go ahead and move this issue into the core repo.

Is this something you'd be willing to submit a pull request for?

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.