exports.increaseRating = functions.database.ref('/comments/')
    .onUpdate((snapshot) => {

        var updates = [];

        snapshot.before.forEach((element) => {
            var comment = element.val();
            comment.rating += 1000;
            updates.push(comment);
        });

        return updates;
    })

return admin.database().ref(`/comments/${context.params.commentId}`).update({
            "rating": newRating
        })