I’m using Mongoose and MongoDB and Nodejs and I want to listen for changes if updatedFields has more then one key.
Can i check updateDescription.updatedFields keys size ?

I can check every key like this:

const filter = [{
    $match: {
        $or: [
            { "updateDescription.updatedFields.key0": { $exists: true } },
            { "updateDescription.updatedFields.key1": { $exists: true } },
            { "updateDescription.updatedFields.key2": { $exists: true } },
            { "updateDescription.updatedFields.key3": { $exists: true } }
            // ...
        ]
    }
}];

const options = { fullDocument: 'updateLookup', fullDocumentBeforeChange: 'whenAvailable' };
myModel.collection('myCollection').watch(filter, options).on('change', async  (event) => 
{
    console.log('event:', event);
});