[{_id:"product1",price:5},{_id:"product2",price:3},{_id:"product3",price:7},{_id:"product4",price:9}]

db.collection.aggregate([{"$match":{_id:{$in:["product1","product4","product3","product1","product1"]}}},{"$set":{"totalPrice":{"$function":{"body":"function(arrOfIds,_id,price) {try { var total=0; arrOfIds.forEach((entry) => { if (entry=== _id){total= total+price;}})} catch (e) {row_number= 0;}return total;}","args":[["product1","product4","product3","product1","product1"],"$_id","$price"],"lang":"js"}}}}])