Stock Price Checker - How to deal with MongoDB Cursor and Document

Hey guys, I really need some HELP here. First of all, I’m not using mongoose on this project, but I don’t think that’s the cause of my problem. So, according to MongoDB docs, the method db.collection.find() returns a cursor while the method db.collection.findOne() returns a document. Let’s cut the long story short, the thing is: I can iterate over a cursor retrieved from the mongo find() query through cursor.forEach(data => {/* do whatever */}), but I can’t store the data from the iterator for later appending it in my res.json({}) response. How can I solve this riddle?
If anyone courageous wants to have a look at my messy code, this is my project.
Any reply would be much appreciated. Cheers mates!