"Skip" value is giving error , return negetive value by default

I have got this error:

MongoServerError: Skip value must be non-negative, but received: -9223372036854775808

router request:

router.post("/products/by/search", listBySearch);

listBySearch method in product controller:

exports.listBySearch = (req, res) => {
    let order = req.body.order ? req.body.order : "desc";
    let sortBy = req.body.sortBy ? req.body.sortBy : "_id";
    let limit = req.body.limit ? parseInt(req.body.limit) : 100;
    let skip = parseInt(req.body.skip);
    let findArgs = {};

    // console.log(order, sortBy, limit, skip, req.body.filters);
    // console.log("findArgs", findArgs);

    for (let key in req.body.filters) {
        if (req.body.filters[key].length > 0) {
            if (key === "price") {
                // gte - greater than price [0-10]
                // lte - less than
                findArgs[key] = {
                    $gte: req.body.filters[key][0],
                    $lte: req.body.filters[key][1]
                };
            } else {
                findArgs[key] = req.body.filters[key];
            }
        }
    }

    Product.find(findArgs)
        .select("-photo")
        .populate("category")
        .sort([
            [sortBy, order]
        ])
        .skip(skip)
        .limit(limit)
        .exec((err, data) => {
            if (err) {
                console.log(err);
                return res.status(400).json({
                    error: "Products not found"
                });
            }
            res.json({
                size: data.length,
                data
            });
        });
};

>Solution :

As you state in your comments, the issue occurs when there’s no value for skip passed in req.body, which means skip = parseInt(undefined), which is NaN.

Instead, try setting a default skip value of 0:

let skip = parseInt(req.body.skip) || 0;