c# - Translate FilterDefinition<TDocument> to regular json mongo query that i can run in a mongo shell

Question

I have many complex queries that I sometimes wish to check directly against Mongo for debugging explaining() purposes. With the newer 2.0+ c# driver, i'm not sure how to do this. With the previous version there was a thing called IMongoQuery and This worked.

A simple example:

FilterDefinition<LalalaEvent> filter = Builders<LalalaEvent>.Filter
    .Where(e => ids.Contains(e.Id) && e.Deleted != true );

Answer 1

I was trying to solve the same problem today. Here is what I found.

public static class MongoExtensions
{
    public static BsonDocument RenderToBsonDocument<T>(this FilterDefinition<T> filter)
    {
        var serializerRegistry = BsonSerializer.SerializerRegistry;
        var documentSerializer = serializerRegistry.GetSerializer<T>();
        return filter.Render(documentSerializer, serializerRegistry);
    }
}

I didn't have access to a collection when I was calling it, so I couldn't use the above solutions.

This allows you to do

var json = filter.RenderToBsonDocument().ToJson();