EF Core 7 CosmosDb - Using entity with SmartEnum property causes EF Core to create entries in another container

[nhwilly]

If anyone is interested, I can write up a whole thing, but I narrowed it down.

In EF Core for Cosmos, OwnsMany properties are automatically embedded in the document (item) as an array.

In my case, I had an Invitation aggregate that had a list of InvitationEvents. Each InvitationEvent contained a DateTimeOffset and an InvitationEventType, which was a SmartEnum. Defined as below:

[JsonConverter(typeof(SmartEnumNameConverter<InvitationEventType, int>))]
public InvitationEventType InvitationEventType { get; init; }

What was happening was that each event was being written to the default Cosmos container with a default Guid value. That is, the Invitation ended up in the proper container and the InvitationEvents ended up in the default container. Wild.

If I changed that SmartEnum to a simple enum, my document contained a collection of InvitationEvents as expected, with no configuration.

If you're seeing something nutty with your child objects, I hope this helps.

p.s. Yes, I'm using modelBuilder.ConfigureSmartEnum();
p.p.s. No, I did not try this with EF Core on a SQL Provider.