Can't determine serialization information for i => i.Id using interfaces

First of all, I know there are already questions with this error message, but I haven't found any references to use interfaces with this type of request.

I am currently trying to update MongoDB object with C # Driver 2.0. However, I get an error when I try to create a request (I assume this is a bit of code Builders<T>.Filter.Eq(i => i.Id, entity.Id)

) and I get the following error:

Unable to determine serialization information for i => i.Id.

I have the following class which I am trying to update

public interface IEntity {
    string Id { get; set; }
}

public interface ITrack : IEntity {
    string Name { get; set; }
}

public class TrackDTO : ITrack
{

    [BsonId]
    public string Id { get; set; }

    public string Name { get; set; }

}

      

        
        
        
      

    

Then I use the interface to store the object in the database using the following method in the general DAO class to replace the entire document. Note that in the example below, T is encoded as ITrack

(i.e. TrackDao = new Dao<ITrack>

), but when an object is passed at runtime, it is an object TrackDTO

(which is correct):

public async Task<T> Save(T entity)
{
    // Save the entity to the collection.
    ReplaceOneResult result = await _collection.ReplaceOneAsync(Builders<T>.Filter.Eq(i => i.Id, entity.Id), entity, new UpdateOptions() { IsUpsert = true });

    // return the saved user object.
    return entity;
}

      

        
        
        
      

    

I don't know if the Id property of my class requires an IEntity

attribute [BsonId]

, but I would like to avoid that if possible, since I want to store my model layer (where IEntity

) without any specific reference to the database framework.

I also tried adding the following classmap, which also had no effect:

BsonClassMap.RegisterClassMap<TrackDTO>(cm =>
{
    cm.AutoMap();
    cm.MapMember(c => c.Id).SetSerializer(new StringSerializer(BsonType.ObjectId));
    cm.SetIdMember(cm.GetMemberMap(c => c.Id));
});

      

        
        
        
      

    

For the same reason as the lack of attributes [BsonId]

at the model level, I do not want the decorated Model classes to [BsonKnownTypes]

reference DTO objects, however I do not mind if it is necessary to happen as part of the class map.