Partial indexes in mongodb / mongoose

Question

In the sparse index documentation I found note about mongodb 3.2 partial indexes

Changed in version 3.2: Starting in MongoDB 3.2, MongoDB provides the

Answer 1

Now it's possible natively with Mongoose +4.6.1

Book.index({user: 1, author: 1, complete: 1}, {unique: true, partialFilterExpression: {complete: true}});