MongoDB Use $in with array of objects

Question

I have a collection with documents in a MongoDB like this:

{
   "recipe_id": "123",
   "recipe_name": "Pizza",
   "recipe_author": "Jane Doe"
{

Then, in JavaScript, I have an array of objects like this:

[{
   "author": "John Doe"
}
{
   "author": "Jane Doe"
}]

I want to find at least one document where the recipe_author field in MongoDB matches the author field in my JavaScript array of objects, so I can get the author_id.

If my authors were in an array, I could check for them all at once like this:

["Jane Doe", "Billy Bob", "Another Author"]

collection.findOne({
   'author_name': { $in: authors }
}

But, they are an array of objects. Is it possible to do something along these lines?

collection.findOne({ 'author_name': { $in: <each author field in my object> } }

Answer 1

I think iterating author inside $in construct may not be possible , but prior querying required array can be formed .

 var author = [{
       "author": "John Doe"
    }
    {
       "author": "Jane Doe"
    }];

    var authorObj = author.map(function(eachObj){
                   return eachObj.author;
    });

    collection.findOne({
       'author_name': { $in: authorObj }
    }